Module materialize.mzcompose
The implementation of the mzcompose system for Docker compositions.
For an overview of what mzcompose is and why it exists, see the user-facing documentation.
Expand source code Browse git
# Copyright Materialize, Inc. and contributors. All rights reserved.
#
# Use of this software is governed by the Business Source License
# included in the LICENSE file at the root of this repository.
#
# As of the Change Date specified in that file, in accordance with
# the Business Source License, use of this software will be governed
# by the Apache License, Version 2.0.
"""The implementation of the mzcompose system for Docker compositions.
For an overview of what mzcompose is and why it exists, see the [user-facing
documentation][user-docs].
[user-docs]: https://github.com/MaterializeInc/materialize/blob/main/doc/developer/mzbuild.md
"""
import argparse
import copy
import importlib
import importlib.abc
import importlib.util
import inspect
import os
import re
import subprocess
import sys
import time
import traceback
from contextlib import contextmanager
from dataclasses import dataclass
from inspect import getmembers, isfunction
from pathlib import Path
from tempfile import TemporaryFile
from typing import (
Any,
Callable,
Dict,
Iterable,
Iterator,
List,
Literal,
Optional,
OrderedDict,
Sequence,
Tuple,
TypedDict,
TypeVar,
Union,
cast,
)
import pg8000
import sqlparse
import yaml
from pg8000 import Cursor
from materialize import mzbuild, spawn, ui
from materialize.ui import UIError
T = TypeVar("T")
say = ui.speaker("C> ")
class UnknownCompositionError(UIError):
"""The specified composition was unknown."""
def __init__(self, name: str):
super().__init__(f"unknown composition {name!r}")
class LintError:
def __init__(self, file: Path, message: str):
self.file = file
self.message = message
def __str__(self) -> str:
return f"{os.path.relpath(self.file)}: {self.message}"
def __lt__(self, other: "LintError") -> bool:
return (self.file, self.message) < (other.file, other.message)
def _lint_composition(path: Path, composition: Any, errors: List[LintError]) -> None:
if "services" not in composition:
return
for (name, service) in composition["services"].items():
if "mzbuild" not in service and "image" in service:
_lint_image_name(path, service["image"], errors)
if isinstance(service.get("environment"), dict):
errors.append(
LintError(
path, f"environment for service {name} uses dict instead of list"
)
)
def _lint_image_name(path: Path, spec: str, errors: List[LintError]) -> None:
from materialize.mzcompose.services import (
DEFAULT_CONFLUENT_PLATFORM_VERSION,
LINT_DEBEZIUM_VERSIONS,
)
match = re.search(r"((?P<repo>[^/]+)/)?(?P<image>[^:]+)(:(?P<tag>.*))?", spec)
if not match:
errors.append(LintError(path, f"malformatted image specification: {spec}"))
return
(repo, image, tag) = (match.group("repo"), match.group("image"), match.group("tag"))
if not tag:
errors.append(LintError(path, f"image {spec} missing tag"))
elif tag == "latest":
errors.append(LintError(path, f'image {spec} depends on floating "latest" tag'))
if repo == "confluentinc" and image.startswith("cp-"):
# An '$XXX' environment variable may have been used to specify the version
if "$" not in tag and tag != DEFAULT_CONFLUENT_PLATFORM_VERSION:
errors.append(
LintError(
path,
f"image {spec} depends on wrong version of Confluent Platform "
f"(want {DEFAULT_CONFLUENT_PLATFORM_VERSION})",
)
)
if repo == "debezium":
if "$" not in tag and tag not in LINT_DEBEZIUM_VERSIONS:
errors.append(
LintError(
path,
f"image {spec} depends on wrong version of Debezium "
f"(want {LINT_DEBEZIUM_VERSIONS})",
)
)
if not repo and image == "zookeeper":
errors.append(
LintError(
path, f"replace {spec} with official confluentinc/cp-zookeeper image"
)
)
if repo == "wurstmeister" and image == "kafka":
errors.append(
LintError(path, f"replace {spec} with official confluentinc/cp-kafka image")
)
class Composition:
"""A parsed mzcompose.yml with a loaded mzcompose.py file."""
@dataclass
class TestResult:
duration: float
error: Optional[str]
def __init__(
self,
repo: mzbuild.Repository,
name: str,
preserve_ports: bool = False,
silent: bool = False,
munge_services: bool = True,
):
self.name = name
self.description = None
self.repo = repo
self.preserve_ports = preserve_ports
self.silent = silent
self.workflows: Dict[str, Callable[..., None]] = {}
self.test_results: OrderedDict[str, Composition.TestResult] = OrderedDict()
if name in self.repo.compositions:
self.path = self.repo.compositions[name]
else:
raise UnknownCompositionError(name)
# load the mzcompose.yml file, if one exists
mzcompose_yml = self.path / "mzcompose.yml"
if mzcompose_yml.exists():
with open(mzcompose_yml) as f:
compose = yaml.safe_load(f) or {}
else:
compose = {}
self.compose = compose
if "version" not in compose:
compose["version"] = "3.7"
if "services" not in compose:
compose["services"] = {}
# Load the mzcompose.py file, if one exists
mzcompose_py = self.path / "mzcompose.py"
if mzcompose_py.exists():
spec = importlib.util.spec_from_file_location("mzcompose", mzcompose_py)
assert spec
module = importlib.util.module_from_spec(spec)
assert isinstance(spec.loader, importlib.abc.Loader)
spec.loader.exec_module(module)
self.description = inspect.getdoc(module)
for name, fn in getmembers(module, isfunction):
if name.startswith("workflow_"):
# The name of the workflow is the name of the function
# with the "workflow_" prefix stripped and any underscores
# replaced with dashes.
name = name[len("workflow_") :].replace("_", "-")
self.workflows[name] = fn
for python_service in getattr(module, "SERVICES", []):
name = python_service.name
if name in compose["services"]:
raise UIError(f"service {name!r} specified more than once")
compose["services"][name] = python_service.config
# Add default volumes
compose.setdefault("volumes", {}).update(
{
"mzdata": None,
"pgdata": None,
"mydata": None,
"tmp": None,
"secrets": None,
}
)
# The CLI driver will handle acquiring these dependencies.
if munge_services:
self.dependencies = self._munge_services(compose["services"].items())
# Emit the munged configuration to a temporary file so that we can later
# pass it to Docker Compose.
self.file = TemporaryFile(mode="w")
os.set_inheritable(self.file.fileno(), True)
self._write_compose()
def _munge_services(
self, services: List[Tuple[str, dict]]
) -> mzbuild.DependencySet:
images = []
for name, config in services:
# Remember any mzbuild references.
if "mzbuild" in config:
image_name = config["mzbuild"]
if image_name not in self.repo.images:
raise UIError(f"mzcompose: unknown image {image_name}")
image = self.repo.images[image_name]
images.append(image)
if "propagate_uid_gid" in config:
if config["propagate_uid_gid"]:
config["user"] = f"{os.getuid()}:{os.getgid()}"
del config["propagate_uid_gid"]
ports = config.setdefault("ports", [])
for i, port in enumerate(ports):
if self.preserve_ports and not ":" in str(port):
# If preserving ports, bind the container port to the same
# host port, assuming the host port is available.
ports[i] = f"{port}:{port}"
elif ":" in str(port) and not config.get("allow_host_ports", False):
# Raise an error for host-bound ports, unless
# `allow_host_ports` is `True`
raise UIError(
"programming error: disallowed host port in service {name!r}",
hint=f'Add `"allow_host_ports": True` to the service config to disable this check.',
)
if "allow_host_ports" in config:
config.pop("allow_host_ports")
if self.repo.rd.coverage:
# Emit coverage information to a file in a directory that is
# bind-mounted to the "coverage" directory on the host. We
# inject the configuration to all services for simplicity, but
# this only have an effect if the service runs instrumented Rust
# binaries.
config.setdefault("environment", []).append(
f"LLVM_PROFILE_FILE=/coverage/{name}-%m.profraw"
)
config.setdefault("volumes", []).append("./coverage:/coverage")
# Determine mzbuild specs and inject them into services accordingly.
deps = self.repo.resolve_dependencies(images)
for _name, config in services:
if "mzbuild" in config:
config["image"] = deps[config["mzbuild"]].spec()
del config["mzbuild"]
return deps
def _write_compose(self) -> None:
self.file.seek(0)
self.file.truncate()
yaml.dump(self.compose, self.file)
self.file.flush()
@classmethod
def lint(cls, repo: mzbuild.Repository, name: str) -> List[LintError]:
"""Checks a composition for common errors."""
if not name in repo.compositions:
raise UnknownCompositionError(name)
errs: List[LintError] = []
path = repo.compositions[name] / "mzcompose.yml"
if path.exists():
with open(path) as f:
composition = yaml.safe_load(f) or {}
_lint_composition(path, composition, errs)
return errs
def invoke(
self, *args: str, capture: bool = False, stdin: Optional[str] = None
) -> subprocess.CompletedProcess:
"""Invoke `docker compose` on the rendered composition.
Args:
args: The arguments to pass to `docker compose`.
capture: Whether to capture the child's stdout stream.
input: A string to provide as stdin for the command.
"""
if not self.silent:
print(f"$ docker compose {' '.join(args)}", file=sys.stderr)
self.file.seek(0)
stdout = None
if capture:
stdout = subprocess.PIPE
try:
return subprocess.run(
[
"docker",
"compose",
*(["--log-level=ERROR"] if self.silent else []),
f"-f/dev/fd/{self.file.fileno()}",
"--project-directory",
self.path,
*args,
],
close_fds=False,
check=True,
stdout=stdout,
input=stdin,
text=True,
)
except subprocess.CalledProcessError as e:
if e.stdout:
print(e.stdout)
raise UIError(f"running docker compose failed (exit status {e.returncode})")
def port(self, service: str, private_port: Union[int, str]) -> int:
"""Get the public port for a service's private port.
Delegates to `docker compose port`. See that command's help for details.
Args:
service: The name of a service in the composition.
private_port: A private port exposed by the service.
"""
proc = self.invoke("port", service, str(private_port), capture=True)
if not proc.stdout.strip():
raise UIError(
f"service f{service!r} is not exposing port {private_port!r}",
hint="is the service running?",
)
return int(proc.stdout.split(":")[1])
def default_port(self, service: str) -> int:
"""Get the default public port for a service.
Args:
service: The name of a service in the composition.
"""
ports = self.compose["services"][service]["ports"]
if not ports:
raise UIError(f"service f{service!r} does not expose any ports")
private_port = str(ports[0]).split(":")[0]
return self.port(service, private_port)
def workflow(self, name: str, *args: str) -> None:
"""Run a workflow in the composition.
Raises a `KeyError` if the workflow does not exist.
Args:
name: The name of the workflow to run.
args: The arguments to pass to the workflow function.
"""
ui.header(f"Running workflow {name}")
func = self.workflows[name]
parser = WorkflowArgumentParser(name, inspect.getdoc(func), list(args))
if len(inspect.signature(func).parameters) > 1:
func(self, parser)
else:
# If the workflow doesn't have an `args` parameter, parse them here
# with an empty parser to reject bogus arguments and to handle the
# trivial help message.
parser.parse_args()
func(self)
@contextmanager
def override(self, *services: "Service") -> Iterator[None]:
"""Temporarily update the composition with the specified services.
The services must already exist in the composition. They restored to
their old definitions when the `with` block ends. Note that the service
definition is written in its entirety; i.e., the configuration is not
deep merged but replaced wholesale.
Lest you are tempted to change this function to allow dynamically
injecting new services: do not do this! These services will not be
visible to other commands, like `mzcompose run`, `mzcompose logs`, or
`mzcompose down`, which makes debugging or inspecting the composition
challenging.
"""
# Remember the old composition.
old_compose = copy.deepcopy(self.compose)
# Update the composition with the new service definitions.
deps = self._munge_services([(s.name, cast(dict, s.config)) for s in services])
for service in services:
self.compose["services"][service.name] = service.config
# Re-acquire dependencies, as the override may have swapped an `image`
# config for an `mzbuild` config.
deps.acquire()
self._write_compose()
# Ensure image freshness
self.pull_if_variable([service.name for service in services])
try:
# Run the next composition.
yield
finally:
# Restore the old composition.
self.compose = old_compose
self._write_compose()
@contextmanager
def test_case(self, name: str) -> Iterator[None]:
"""Execute a test case.
This context manager provides a very lightweight testing framework. If
the body of the context manager raises an exception, the test case is
considered to have failed; otherwise it is considered to have succeeded.
In either case the execution time and status of the test are recorded in
`test_results`.
Example:
A simple workflow that executes a table-driven test:
```
@dataclass
class TestCase:
name: str
files: list[str]
test_cases = [
TestCase(name="short", files=["quicktests.td"]),
TestCase(name="long", files=["longtest1.td", "longtest2.td"]),
]
def workflow_default(c: Composition):
for tc in test_cases:
with c.test_case(tc.name):
c.run("testdrive", *tc.files)
```
Args:
name: The name of the test case. Must be unique across the lifetime
of a composition.
"""
if name in self.test_results:
raise UIError(f"test case {name} executed twice")
ui.header(f"Running test case {name}")
error = None
start_time = time.time()
try:
yield
ui.header(f"mzcompose: test case {name} succeeded")
except Exception as e:
error = str(e)
if isinstance(e, UIError):
print(f"mzcompose: test case {name} failed: {e}", file=sys.stderr)
else:
print(f"mzcompose: test case {name} failed:", file=sys.stderr)
traceback.print_exc()
elapsed = time.time() - start_time
self.test_results[name] = Composition.TestResult(elapsed, error)
def sql_cursor(self) -> Cursor:
"""Get a cursor to run SQL queries against the materialized service."""
port = self.default_port("materialized")
conn = pg8000.connect(host="localhost", user="materialize", port=port)
conn.autocommit = True
return conn.cursor()
def sql(self, sql: str) -> None:
"""Run a batch of SQL statements against the materialized service."""
with self.sql_cursor() as cursor:
for statement in sqlparse.split(sql):
print(f"> {statement}")
cursor.execute(statement)
def sql_query(self, sql: str) -> Any:
"""Execute and return results of a SQL query."""
with self.sql_cursor() as cursor:
cursor.execute(sql)
return cursor.fetchall()
def create_cluster(
self,
cluster: List,
cluster_name: str = "cluster1",
replica_name: str = "replica1",
) -> None:
"""Construct and run a CREATE CLUSTER statement based a list of Computed instances
Args:
cluster: a List of Computed instances that will form the cluster
cluster_name: The cluster name to use
replica_name: The replica name to use
"""
self.sql(
f"CREATE CLUSTER {cluster_name} REPLICAS ( {replica_name} ( REMOTE ["
+ ", ".join(f'"{p.name}:2100"' for p in cluster)
+ "]))"
)
def start_and_wait_for_tcp(self, services: List[str]) -> None:
"""Sequentially start the named services, waiting for eaach to become
available via TCP before moving on to the next."""
for service in services:
self.up(service)
for port in self.compose["services"][service].get("ports", []):
self.wait_for_tcp(host=service, port=port)
def run(
self,
service: str,
*args: str,
detach: bool = False,
rm: bool = False,
env_extra: Dict[str, str] = {},
capture: bool = False,
stdin: Optional[str] = None,
) -> subprocess.CompletedProcess:
"""Run a one-off command in a service.
Delegates to `docker compose run`. See that command's help for details.
Note that unlike `docker compose run`, any services whose definitions
have changed are rebuilt (like `docker compose up` would do) before the
command is executed.
Args:
service: The name of a service in the composition.
args: Arguments to pass to the service's entrypoint.
detach: Run the container in the background.
stdin: read STDIN from a string.
env_extra: Additional environment variables to set in the container.
rm: Remove container after run.
capture: Capture the stdout of the `docker compose` invocation.
"""
# Restart any dependencies whose definitions have changed. The trick,
# taken from Buildkite's Docker Compose plugin, is to run an `up`
# command that requests zero instances of the requested service.
self.invoke("up", "--detach", "--scale", f"{service}=0", service)
return self.invoke(
"run",
*(f"-e{k}={v}" for k, v in env_extra.items()),
*(["--detach"] if detach else []),
*(["--rm"] if rm else []),
service,
*args,
capture=capture,
stdin=stdin,
)
def exec(
self,
service: str,
*args: str,
detach: bool = False,
capture: bool = False,
stdin: Optional[str] = None,
) -> subprocess.CompletedProcess:
"""Execute a one-off command in a service's running container
Delegates to `docker compose exec`.
Args:
service: The service whose container will be used.
command: The command to run.
args: Arguments to pass to the command.
detach: Run the container in the background.
stdin: read STDIN from a string.
"""
return self.invoke(
"exec",
*(["--detach"] if detach else []),
"-T",
service,
*(
self.compose["services"][service]["entrypoint"]
if "entrypoint" in self.compose["services"][service]
else []
),
*args,
capture=capture,
stdin=stdin,
)
def pull_if_variable(self, services: List[str]) -> None:
"""Pull fresh service images in case the tag indicates thee underlying image may change over time.
Args:
services: List of service names
"""
for service in services:
if "image" in self.compose["services"][service] and any(
self.compose["services"][service]["image"].endswith(tag)
for tag in [":latest", ":unstable", ":rolling"]
):
self.invoke("pull", service)
def up(self, *services: str, detach: bool = True, persistent: bool = False) -> None:
"""Build, (re)create, and start the named services.
Delegates to `docker compose up`. See that command's help for details.
Args:
services: The names of services in the composition.
detach: Run containers in the background.
persistent: Replace the container's entrypoint and command with
`sleep infinity` so that additional commands can be scheduled
on the container with `Composition.exec`.
"""
if persistent:
old_compose = copy.deepcopy(self.compose)
for service in self.compose["services"].values():
service["entrypoint"] = ["sleep", "infinity"]
service["command"] = []
self._write_compose()
self.invoke("up", *(["--detach"] if detach else []), *services)
if persistent:
self.compose = old_compose
self._write_compose()
def down(self, destroy_volumes: bool = True, remove_orphans: bool = True) -> None:
"""Stop and remove resources.
Delegates to `docker compose down`. See that command's help for details.
Args:
destroy_volumes: Remove named volumes and anonymous volumes attached
to containers.
"""
self.invoke(
"down",
*(["--volumes"] if destroy_volumes else []),
*(["--remove-orphans"] if remove_orphans else []),
)
def stop(self, *services: str) -> None:
"""Stop the docker containers for the named services.
Delegates to `docker compose stop`. See that command's help for details.
Args:
services: The names of services in the composition.
"""
self.invoke("stop", *services)
def kill(self, *services: str, signal: str = "SIGKILL") -> None:
"""Force stop service containers.
Delegates to `docker compose kill`. See that command's help for details.
Args:
services: The names of services in the composition.
signal: The signal to deliver.
"""
self.invoke("kill", f"-s{signal}", *services)
def pause(self, *services: str) -> None:
"""Pause service containers.
Delegates to `docker compose pause`. See that command's help for details.
Args:
services: The names of services in the composition.
"""
self.invoke("pause", *services)
def unpause(self, *services: str) -> None:
"""Unpause service containers
Delegates to `docker compose unpause`. See that command's help for details.
Args:
services: The names of services in the composition.
"""
self.invoke("unpause", *services)
def rm(
self, *services: str, stop: bool = True, destroy_volumes: bool = True
) -> None:
"""Remove stopped service containers.
Delegates to `docker compose rm`. See that command's help for details.
Args:
services: The names of services in the composition.
stop: Stop the containers if necessary.
destroy_volumes: Destroy any anonymous volumes associated with the
service. Note that this does not destroy any named volumes
attached to the service.
"""
self.invoke(
"rm",
"--force",
*(["--stop"] if stop else []),
*(["-v"] if destroy_volumes else []),
*services,
)
def rm_volumes(self, *volumes: str, force: bool = False) -> None:
"""Remove the named volumes.
Args:
volumes: The names of volumes in the composition.
force: Whether to force the removal (i.e., don't error if the
volume does not exist).
"""
volumes = (f"{self.name}_{v}" for v in volumes)
spawn.runv(
["docker", "volume", "rm", *(["--force"] if force else []), *volumes]
)
def sleep(self, duration: float) -> None:
"""Sleep for the specified duration in seconds."""
print(f"Sleeping for {duration} seconds...")
time.sleep(duration)
# TODO(benesch): replace with Docker health checks.
def wait_for_tcp(
self,
*,
host: str = "localhost",
port: Union[int, str],
timeout_secs: int = 240,
) -> None:
if isinstance(port, str):
port = int(port.split(":")[0])
ui.progress(f"waiting for {host}:{port}", "C")
cmd = f"docker run --rm -t --network {self.name}_default ubuntu:focal-20210723".split()
try:
_check_tcp(cmd[:], host, port, timeout_secs)
except subprocess.CalledProcessError:
ui.progress(" error!", finish=True)
raise UIError(f"unable to connect to {host}:{port}")
else:
ui.progress(" success!", finish=True)
# TODO(benesch): replace with Docker health checks.
def wait_for_postgres(
self,
*,
dbname: str = "postgres",
port: Optional[int] = None,
host: str = "localhost",
timeout_secs: int = 120,
query: str = "SELECT 1",
user: str = "postgres",
password: str = "postgres",
expected: Union[Iterable[Any], Literal["any"]] = [[1]],
print_result: bool = False,
service: str = "postgres",
) -> None:
"""Wait for a PostgreSQL service to start.
Args:
dbname: the name of the database to wait for
host: the host postgres is listening on
port: the port postgres is listening on
timeout_secs: How long to wait for postgres to be up before failing (Default: 30)
query: The query to execute to ensure that it is running (Default: "Select 1")
user: The chosen user (this is only relevant for postgres)
service: The service that postgres is running as (Default: postgres)
"""
_wait_for_pg(
dbname=dbname,
host=host,
port=self.port(service, port) if port else self.default_port(service),
timeout_secs=timeout_secs,
query=query,
user=user,
password=password,
expected=expected,
print_result=print_result,
)
# TODO(benesch): replace with Docker health checks.
def wait_for_materialized(
self,
service: str = "materialized",
*,
user: str = "materialize",
dbname: str = "materialize",
host: str = "localhost",
port: Optional[int] = None,
timeout_secs: int = 60,
query: str = "SELECT 1",
expected: Union[Iterable[Any], Literal["any"]] = [[1]],
print_result: bool = False,
) -> None:
"""Like `Workflow.wait_for_postgres`, but with Materialize defaults."""
self.wait_for_postgres(
user=user,
dbname=dbname,
host=host,
port=port,
timeout_secs=timeout_secs,
query=query,
expected=expected,
print_result=print_result,
service=service,
)
def testdrive(
self,
input: str,
service: str = "testdrive",
persistent: bool = True,
args: List[str] = [],
) -> None:
"""Run a string as a testdrive script.
Args:
args: Additional arguments to pass to testdrive
service: Optional name of the testdrive service to use.
input: The string to execute.
persistent: Whether a persistent testdrive container will be used.
"""
if persistent:
self.exec(service, *args, stdin=input)
else:
self.run(service, *args, stdin=input)
class ServiceConfig(TypedDict, total=False):
"""The definition of a service in Docker Compose.
This object corresponds directly to the YAML definition in a
docker-compose.yml file, plus two mzcompose-specific attributes. Full
details are available in [Services top-level element][ref] chapter of the
Compose Specification.
[ref]: https://github.com/compose-spec/compose-spec/blob/master/spec.md#services-top-level-element
"""
mzbuild: str
"""The name of an mzbuild image to dynamically acquire before invoking
Docker Compose.
This is a mzcompose-extension to Docker Compose. The image must exist in
the repository. If `mzbuild` is set, neither `build` nor `image` should be
set.
"""
propagate_uid_gid: bool
"""Request that the Docker image be run with the user ID and group ID of the
host user.
This is an mzcompose extension to Docker Compose. It is equivalent to
passing `--user $(id -u):$(id -g)` to `docker run`. The defualt is `False`.
"""
allow_host_ports: bool
"""Allow the service to map host ports in its `ports` configuration.
This option is intended only for compositions that are meant to be run as
background services in developer environments. Compositions that are
isolated tests of Materialize should *not* enable this option, as it leads
to unnecessary conflicts between compositions. Compositions that publish the
same host port cannot be run concurrently. Instead, users should use the
`mzcompose port` command to discover the ephemeral host port mapped to the
desired container port, or to use `mzcompose up --preserve-ports`, which
publishes all container ports as host ports on a per-invocation basis.
"""
image: str
"""The name and tag of an image on Docker Hub."""
hostname: str
"""The hostname to use.
By default, the name of the service is used as the hostname.
"""
entrypoint: List[str]
"""Override the entrypoint specified in the image."""
command: str
"""Override the command specified in the image."""
init: bool
"""Whether to run an init process in the container."""
ports: Sequence[Union[int, str]]
"""Service ports to expose to the host."""
environment: List[str]
"""Additional environment variables to set.
Each entry must be in the form `NAME=VALUE`.
TODO(benesch): this should accept a `Dict[str, str]` instead.
"""
depends_on: List[str]
"""The list of other services that must be started before this one."""
volumes: List[str]
"""Volumes to attach to the service."""
networks: Dict[str, Dict[str, List[str]]]
"""Additional networks to join.
TODO(benesch): this should use a nested TypedDict.
"""
deploy: Dict[str, Dict[str, Dict[str, str]]]
"""Additional deployment configuration, like resource limits.
TODO(benesch): this should use a nested TypedDict.
"""
ulimits: Dict[str, Any]
"""Override the default ulimits for a container."""
working_dir: str
"""Overrides the container's working directory."""
class Service:
"""A Docker Compose service in a `Composition`.
Attributes:
name: The name of the service.
config: The definition of the service.
"""
def __init__(self, name: str, config: ServiceConfig) -> None:
self.name = name
self.config = config
class WorkflowArgumentParser(argparse.ArgumentParser):
"""An argument parser provided to a workflow in a `Composition`.
You can call `add_argument` and other methods on this argument parser like
usual. When you are ready to parse arguments, call `parse_args` or
`parse_known_args` like usual; the argument parser will automatically use
the arguments that the user provided to the workflow.
"""
def __init__(self, name: str, description: Optional[str], args: List[str]):
self.args = args
super().__init__(prog=f"mzcompose run {name}", description=description)
def parse_known_args(
self,
args: Optional[Sequence[str]] = None,
namespace: Optional[argparse.Namespace] = None,
) -> Tuple[argparse.Namespace, List[str]]:
if args is None:
args = self.args
return super().parse_known_args(args, namespace)
# TODO(benesch): replace with Docker health checks.
def _check_tcp(
cmd: List[str], host: str, port: int, timeout_secs: int, kind: str = ""
) -> List[str]:
cmd.extend(
[
"timeout",
str(timeout_secs),
"bash",
"-c",
f"until [ cat < /dev/null > /dev/tcp/{host}/{port} ] ; do sleep 0.1 ; done",
]
)
try:
spawn.capture(cmd, stderr=subprocess.STDOUT)
except subprocess.CalledProcessError as e:
ui.log_in_automation(
"wait-for-tcp ({}{}:{}): error running {}: {}, stdout:\n{}\nstderr:\n{}".format(
kind, host, port, ui.shell_quote(cmd), e, e.stdout, e.stderr
)
)
raise
return cmd
# TODO(benesch): replace with Docker health checks.
def _wait_for_pg(
timeout_secs: int,
query: str,
dbname: str,
port: int,
host: str,
user: str,
password: str,
print_result: bool,
expected: Union[Iterable[Any], Literal["any"]],
) -> None:
"""Wait for a pg-compatible database (includes materialized)"""
args = f"dbname={dbname} host={host} port={port} user={user} password={password}"
ui.progress(f"waiting for {args} to handle {query!r}", "C")
error = None
for remaining in ui.timeout_loop(timeout_secs, tick=0.1):
try:
conn = pg8000.connect(
database=dbname,
host=host,
port=port,
user=user,
password=password,
timeout=1,
)
# The default (autocommit = false) wraps everything in a transaction.
conn.autocommit = True
cur = conn.cursor()
cur.execute(query)
if expected == "any" and cur.rowcount == -1:
ui.progress("success!", finish=True)
return
result = list(cur.fetchall())
if expected == "any" or result == expected:
if print_result:
say(f"query result: {result}")
else:
ui.progress("success!", finish=True)
return
else:
say(
f"host={host} port={port} did not return rows matching {expected} got: {result}"
)
except Exception as e:
ui.progress(" " + str(int(remaining)))
error = e
ui.progress(finish=True)
raise UIError(f"never got correct result for {args}: {error}")Sub-modules
materialize.mzcompose.services
Classes
class Composition (repo: Repository, name: str, preserve_ports: bool = False, silent: bool = False, munge_services: bool = True)-
A parsed mzcompose.yml with a loaded mzcompose.py file.
Expand source code Browse git
class Composition: """A parsed mzcompose.yml with a loaded mzcompose.py file.""" @dataclass class TestResult: duration: float error: Optional[str] def __init__( self, repo: mzbuild.Repository, name: str, preserve_ports: bool = False, silent: bool = False, munge_services: bool = True, ): self.name = name self.description = None self.repo = repo self.preserve_ports = preserve_ports self.silent = silent self.workflows: Dict[str, Callable[..., None]] = {} self.test_results: OrderedDict[str, Composition.TestResult] = OrderedDict() if name in self.repo.compositions: self.path = self.repo.compositions[name] else: raise UnknownCompositionError(name) # load the mzcompose.yml file, if one exists mzcompose_yml = self.path / "mzcompose.yml" if mzcompose_yml.exists(): with open(mzcompose_yml) as f: compose = yaml.safe_load(f) or {} else: compose = {} self.compose = compose if "version" not in compose: compose["version"] = "3.7" if "services" not in compose: compose["services"] = {} # Load the mzcompose.py file, if one exists mzcompose_py = self.path / "mzcompose.py" if mzcompose_py.exists(): spec = importlib.util.spec_from_file_location("mzcompose", mzcompose_py) assert spec module = importlib.util.module_from_spec(spec) assert isinstance(spec.loader, importlib.abc.Loader) spec.loader.exec_module(module) self.description = inspect.getdoc(module) for name, fn in getmembers(module, isfunction): if name.startswith("workflow_"): # The name of the workflow is the name of the function # with the "workflow_" prefix stripped and any underscores # replaced with dashes. name = name[len("workflow_") :].replace("_", "-") self.workflows[name] = fn for python_service in getattr(module, "SERVICES", []): name = python_service.name if name in compose["services"]: raise UIError(f"service {name!r} specified more than once") compose["services"][name] = python_service.config # Add default volumes compose.setdefault("volumes", {}).update( { "mzdata": None, "pgdata": None, "mydata": None, "tmp": None, "secrets": None, } ) # The CLI driver will handle acquiring these dependencies. if munge_services: self.dependencies = self._munge_services(compose["services"].items()) # Emit the munged configuration to a temporary file so that we can later # pass it to Docker Compose. self.file = TemporaryFile(mode="w") os.set_inheritable(self.file.fileno(), True) self._write_compose() def _munge_services( self, services: List[Tuple[str, dict]] ) -> mzbuild.DependencySet: images = [] for name, config in services: # Remember any mzbuild references. if "mzbuild" in config: image_name = config["mzbuild"] if image_name not in self.repo.images: raise UIError(f"mzcompose: unknown image {image_name}") image = self.repo.images[image_name] images.append(image) if "propagate_uid_gid" in config: if config["propagate_uid_gid"]: config["user"] = f"{os.getuid()}:{os.getgid()}" del config["propagate_uid_gid"] ports = config.setdefault("ports", []) for i, port in enumerate(ports): if self.preserve_ports and not ":" in str(port): # If preserving ports, bind the container port to the same # host port, assuming the host port is available. ports[i] = f"{port}:{port}" elif ":" in str(port) and not config.get("allow_host_ports", False): # Raise an error for host-bound ports, unless # `allow_host_ports` is `True` raise UIError( "programming error: disallowed host port in service {name!r}", hint=f'Add `"allow_host_ports": True` to the service config to disable this check.', ) if "allow_host_ports" in config: config.pop("allow_host_ports") if self.repo.rd.coverage: # Emit coverage information to a file in a directory that is # bind-mounted to the "coverage" directory on the host. We # inject the configuration to all services for simplicity, but # this only have an effect if the service runs instrumented Rust # binaries. config.setdefault("environment", []).append( f"LLVM_PROFILE_FILE=/coverage/{name}-%m.profraw" ) config.setdefault("volumes", []).append("./coverage:/coverage") # Determine mzbuild specs and inject them into services accordingly. deps = self.repo.resolve_dependencies(images) for _name, config in services: if "mzbuild" in config: config["image"] = deps[config["mzbuild"]].spec() del config["mzbuild"] return deps def _write_compose(self) -> None: self.file.seek(0) self.file.truncate() yaml.dump(self.compose, self.file) self.file.flush() @classmethod def lint(cls, repo: mzbuild.Repository, name: str) -> List[LintError]: """Checks a composition for common errors.""" if not name in repo.compositions: raise UnknownCompositionError(name) errs: List[LintError] = [] path = repo.compositions[name] / "mzcompose.yml" if path.exists(): with open(path) as f: composition = yaml.safe_load(f) or {} _lint_composition(path, composition, errs) return errs def invoke( self, *args: str, capture: bool = False, stdin: Optional[str] = None ) -> subprocess.CompletedProcess: """Invoke `docker compose` on the rendered composition. Args: args: The arguments to pass to `docker compose`. capture: Whether to capture the child's stdout stream. input: A string to provide as stdin for the command. """ if not self.silent: print(f"$ docker compose {' '.join(args)}", file=sys.stderr) self.file.seek(0) stdout = None if capture: stdout = subprocess.PIPE try: return subprocess.run( [ "docker", "compose", *(["--log-level=ERROR"] if self.silent else []), f"-f/dev/fd/{self.file.fileno()}", "--project-directory", self.path, *args, ], close_fds=False, check=True, stdout=stdout, input=stdin, text=True, ) except subprocess.CalledProcessError as e: if e.stdout: print(e.stdout) raise UIError(f"running docker compose failed (exit status {e.returncode})") def port(self, service: str, private_port: Union[int, str]) -> int: """Get the public port for a service's private port. Delegates to `docker compose port`. See that command's help for details. Args: service: The name of a service in the composition. private_port: A private port exposed by the service. """ proc = self.invoke("port", service, str(private_port), capture=True) if not proc.stdout.strip(): raise UIError( f"service f{service!r} is not exposing port {private_port!r}", hint="is the service running?", ) return int(proc.stdout.split(":")[1]) def default_port(self, service: str) -> int: """Get the default public port for a service. Args: service: The name of a service in the composition. """ ports = self.compose["services"][service]["ports"] if not ports: raise UIError(f"service f{service!r} does not expose any ports") private_port = str(ports[0]).split(":")[0] return self.port(service, private_port) def workflow(self, name: str, *args: str) -> None: """Run a workflow in the composition. Raises a `KeyError` if the workflow does not exist. Args: name: The name of the workflow to run. args: The arguments to pass to the workflow function. """ ui.header(f"Running workflow {name}") func = self.workflows[name] parser = WorkflowArgumentParser(name, inspect.getdoc(func), list(args)) if len(inspect.signature(func).parameters) > 1: func(self, parser) else: # If the workflow doesn't have an `args` parameter, parse them here # with an empty parser to reject bogus arguments and to handle the # trivial help message. parser.parse_args() func(self) @contextmanager def override(self, *services: "Service") -> Iterator[None]: """Temporarily update the composition with the specified services. The services must already exist in the composition. They restored to their old definitions when the `with` block ends. Note that the service definition is written in its entirety; i.e., the configuration is not deep merged but replaced wholesale. Lest you are tempted to change this function to allow dynamically injecting new services: do not do this! These services will not be visible to other commands, like `mzcompose run`, `mzcompose logs`, or `mzcompose down`, which makes debugging or inspecting the composition challenging. """ # Remember the old composition. old_compose = copy.deepcopy(self.compose) # Update the composition with the new service definitions. deps = self._munge_services([(s.name, cast(dict, s.config)) for s in services]) for service in services: self.compose["services"][service.name] = service.config # Re-acquire dependencies, as the override may have swapped an `image` # config for an `mzbuild` config. deps.acquire() self._write_compose() # Ensure image freshness self.pull_if_variable([service.name for service in services]) try: # Run the next composition. yield finally: # Restore the old composition. self.compose = old_compose self._write_compose() @contextmanager def test_case(self, name: str) -> Iterator[None]: """Execute a test case. This context manager provides a very lightweight testing framework. If the body of the context manager raises an exception, the test case is considered to have failed; otherwise it is considered to have succeeded. In either case the execution time and status of the test are recorded in `test_results`. Example: A simple workflow that executes a table-driven test: ``` @dataclass class TestCase: name: str files: list[str] test_cases = [ TestCase(name="short", files=["quicktests.td"]), TestCase(name="long", files=["longtest1.td", "longtest2.td"]), ] def workflow_default(c: Composition): for tc in test_cases: with c.test_case(tc.name): c.run("testdrive", *tc.files) ``` Args: name: The name of the test case. Must be unique across the lifetime of a composition. """ if name in self.test_results: raise UIError(f"test case {name} executed twice") ui.header(f"Running test case {name}") error = None start_time = time.time() try: yield ui.header(f"mzcompose: test case {name} succeeded") except Exception as e: error = str(e) if isinstance(e, UIError): print(f"mzcompose: test case {name} failed: {e}", file=sys.stderr) else: print(f"mzcompose: test case {name} failed:", file=sys.stderr) traceback.print_exc() elapsed = time.time() - start_time self.test_results[name] = Composition.TestResult(elapsed, error) def sql_cursor(self) -> Cursor: """Get a cursor to run SQL queries against the materialized service.""" port = self.default_port("materialized") conn = pg8000.connect(host="localhost", user="materialize", port=port) conn.autocommit = True return conn.cursor() def sql(self, sql: str) -> None: """Run a batch of SQL statements against the materialized service.""" with self.sql_cursor() as cursor: for statement in sqlparse.split(sql): print(f"> {statement}") cursor.execute(statement) def sql_query(self, sql: str) -> Any: """Execute and return results of a SQL query.""" with self.sql_cursor() as cursor: cursor.execute(sql) return cursor.fetchall() def create_cluster( self, cluster: List, cluster_name: str = "cluster1", replica_name: str = "replica1", ) -> None: """Construct and run a CREATE CLUSTER statement based a list of Computed instances Args: cluster: a List of Computed instances that will form the cluster cluster_name: The cluster name to use replica_name: The replica name to use """ self.sql( f"CREATE CLUSTER {cluster_name} REPLICAS ( {replica_name} ( REMOTE [" + ", ".join(f'"{p.name}:2100"' for p in cluster) + "]))" ) def start_and_wait_for_tcp(self, services: List[str]) -> None: """Sequentially start the named services, waiting for eaach to become available via TCP before moving on to the next.""" for service in services: self.up(service) for port in self.compose["services"][service].get("ports", []): self.wait_for_tcp(host=service, port=port) def run( self, service: str, *args: str, detach: bool = False, rm: bool = False, env_extra: Dict[str, str] = {}, capture: bool = False, stdin: Optional[str] = None, ) -> subprocess.CompletedProcess: """Run a one-off command in a service. Delegates to `docker compose run`. See that command's help for details. Note that unlike `docker compose run`, any services whose definitions have changed are rebuilt (like `docker compose up` would do) before the command is executed. Args: service: The name of a service in the composition. args: Arguments to pass to the service's entrypoint. detach: Run the container in the background. stdin: read STDIN from a string. env_extra: Additional environment variables to set in the container. rm: Remove container after run. capture: Capture the stdout of the `docker compose` invocation. """ # Restart any dependencies whose definitions have changed. The trick, # taken from Buildkite's Docker Compose plugin, is to run an `up` # command that requests zero instances of the requested service. self.invoke("up", "--detach", "--scale", f"{service}=0", service) return self.invoke( "run", *(f"-e{k}={v}" for k, v in env_extra.items()), *(["--detach"] if detach else []), *(["--rm"] if rm else []), service, *args, capture=capture, stdin=stdin, ) def exec( self, service: str, *args: str, detach: bool = False, capture: bool = False, stdin: Optional[str] = None, ) -> subprocess.CompletedProcess: """Execute a one-off command in a service's running container Delegates to `docker compose exec`. Args: service: The service whose container will be used. command: The command to run. args: Arguments to pass to the command. detach: Run the container in the background. stdin: read STDIN from a string. """ return self.invoke( "exec", *(["--detach"] if detach else []), "-T", service, *( self.compose["services"][service]["entrypoint"] if "entrypoint" in self.compose["services"][service] else [] ), *args, capture=capture, stdin=stdin, ) def pull_if_variable(self, services: List[str]) -> None: """Pull fresh service images in case the tag indicates thee underlying image may change over time. Args: services: List of service names """ for service in services: if "image" in self.compose["services"][service] and any( self.compose["services"][service]["image"].endswith(tag) for tag in [":latest", ":unstable", ":rolling"] ): self.invoke("pull", service) def up(self, *services: str, detach: bool = True, persistent: bool = False) -> None: """Build, (re)create, and start the named services. Delegates to `docker compose up`. See that command's help for details. Args: services: The names of services in the composition. detach: Run containers in the background. persistent: Replace the container's entrypoint and command with `sleep infinity` so that additional commands can be scheduled on the container with `Composition.exec`. """ if persistent: old_compose = copy.deepcopy(self.compose) for service in self.compose["services"].values(): service["entrypoint"] = ["sleep", "infinity"] service["command"] = [] self._write_compose() self.invoke("up", *(["--detach"] if detach else []), *services) if persistent: self.compose = old_compose self._write_compose() def down(self, destroy_volumes: bool = True, remove_orphans: bool = True) -> None: """Stop and remove resources. Delegates to `docker compose down`. See that command's help for details. Args: destroy_volumes: Remove named volumes and anonymous volumes attached to containers. """ self.invoke( "down", *(["--volumes"] if destroy_volumes else []), *(["--remove-orphans"] if remove_orphans else []), ) def stop(self, *services: str) -> None: """Stop the docker containers for the named services. Delegates to `docker compose stop`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("stop", *services) def kill(self, *services: str, signal: str = "SIGKILL") -> None: """Force stop service containers. Delegates to `docker compose kill`. See that command's help for details. Args: services: The names of services in the composition. signal: The signal to deliver. """ self.invoke("kill", f"-s{signal}", *services) def pause(self, *services: str) -> None: """Pause service containers. Delegates to `docker compose pause`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("pause", *services) def unpause(self, *services: str) -> None: """Unpause service containers Delegates to `docker compose unpause`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("unpause", *services) def rm( self, *services: str, stop: bool = True, destroy_volumes: bool = True ) -> None: """Remove stopped service containers. Delegates to `docker compose rm`. See that command's help for details. Args: services: The names of services in the composition. stop: Stop the containers if necessary. destroy_volumes: Destroy any anonymous volumes associated with the service. Note that this does not destroy any named volumes attached to the service. """ self.invoke( "rm", "--force", *(["--stop"] if stop else []), *(["-v"] if destroy_volumes else []), *services, ) def rm_volumes(self, *volumes: str, force: bool = False) -> None: """Remove the named volumes. Args: volumes: The names of volumes in the composition. force: Whether to force the removal (i.e., don't error if the volume does not exist). """ volumes = (f"{self.name}_{v}" for v in volumes) spawn.runv( ["docker", "volume", "rm", *(["--force"] if force else []), *volumes] ) def sleep(self, duration: float) -> None: """Sleep for the specified duration in seconds.""" print(f"Sleeping for {duration} seconds...") time.sleep(duration) # TODO(benesch): replace with Docker health checks. def wait_for_tcp( self, *, host: str = "localhost", port: Union[int, str], timeout_secs: int = 240, ) -> None: if isinstance(port, str): port = int(port.split(":")[0]) ui.progress(f"waiting for {host}:{port}", "C") cmd = f"docker run --rm -t --network {self.name}_default ubuntu:focal-20210723".split() try: _check_tcp(cmd[:], host, port, timeout_secs) except subprocess.CalledProcessError: ui.progress(" error!", finish=True) raise UIError(f"unable to connect to {host}:{port}") else: ui.progress(" success!", finish=True) # TODO(benesch): replace with Docker health checks. def wait_for_postgres( self, *, dbname: str = "postgres", port: Optional[int] = None, host: str = "localhost", timeout_secs: int = 120, query: str = "SELECT 1", user: str = "postgres", password: str = "postgres", expected: Union[Iterable[Any], Literal["any"]] = [[1]], print_result: bool = False, service: str = "postgres", ) -> None: """Wait for a PostgreSQL service to start. Args: dbname: the name of the database to wait for host: the host postgres is listening on port: the port postgres is listening on timeout_secs: How long to wait for postgres to be up before failing (Default: 30) query: The query to execute to ensure that it is running (Default: "Select 1") user: The chosen user (this is only relevant for postgres) service: The service that postgres is running as (Default: postgres) """ _wait_for_pg( dbname=dbname, host=host, port=self.port(service, port) if port else self.default_port(service), timeout_secs=timeout_secs, query=query, user=user, password=password, expected=expected, print_result=print_result, ) # TODO(benesch): replace with Docker health checks. def wait_for_materialized( self, service: str = "materialized", *, user: str = "materialize", dbname: str = "materialize", host: str = "localhost", port: Optional[int] = None, timeout_secs: int = 60, query: str = "SELECT 1", expected: Union[Iterable[Any], Literal["any"]] = [[1]], print_result: bool = False, ) -> None: """Like `Workflow.wait_for_postgres`, but with Materialize defaults.""" self.wait_for_postgres( user=user, dbname=dbname, host=host, port=port, timeout_secs=timeout_secs, query=query, expected=expected, print_result=print_result, service=service, ) def testdrive( self, input: str, service: str = "testdrive", persistent: bool = True, args: List[str] = [], ) -> None: """Run a string as a testdrive script. Args: args: Additional arguments to pass to testdrive service: Optional name of the testdrive service to use. input: The string to execute. persistent: Whether a persistent testdrive container will be used. """ if persistent: self.exec(service, *args, stdin=input) else: self.run(service, *args, stdin=input)Class variables
var TestResult
Static methods
def lint(repo: Repository, name: str) ‑> List[LintError]-
Checks a composition for common errors.
Expand source code Browse git
@classmethod def lint(cls, repo: mzbuild.Repository, name: str) -> List[LintError]: """Checks a composition for common errors.""" if not name in repo.compositions: raise UnknownCompositionError(name) errs: List[LintError] = [] path = repo.compositions[name] / "mzcompose.yml" if path.exists(): with open(path) as f: composition = yaml.safe_load(f) or {} _lint_composition(path, composition, errs) return errs
Methods
def create_cluster(self, cluster: List, cluster_name: str = 'cluster1', replica_name: str = 'replica1') ‑> None-
Construct and run a CREATE CLUSTER statement based a list of Computed instances
Args
cluster- a List of Computed instances that will form the cluster
cluster_name- The cluster name to use
replica_name- The replica name to use
Expand source code Browse git
def create_cluster( self, cluster: List, cluster_name: str = "cluster1", replica_name: str = "replica1", ) -> None: """Construct and run a CREATE CLUSTER statement based a list of Computed instances Args: cluster: a List of Computed instances that will form the cluster cluster_name: The cluster name to use replica_name: The replica name to use """ self.sql( f"CREATE CLUSTER {cluster_name} REPLICAS ( {replica_name} ( REMOTE [" + ", ".join(f'"{p.name}:2100"' for p in cluster) + "]))" ) def default_port(self, service: str) ‑> int-
Get the default public port for a service.
Args
service- The name of a service in the composition.
Expand source code Browse git
def default_port(self, service: str) -> int: """Get the default public port for a service. Args: service: The name of a service in the composition. """ ports = self.compose["services"][service]["ports"] if not ports: raise UIError(f"service f{service!r} does not expose any ports") private_port = str(ports[0]).split(":")[0] return self.port(service, private_port) def down(self, destroy_volumes: bool = True, remove_orphans: bool = True) ‑> None-
Stop and remove resources.
Delegates to
docker compose down. See that command's help for details.Args
destroy_volumes- Remove named volumes and anonymous volumes attached to containers.
Expand source code Browse git
def down(self, destroy_volumes: bool = True, remove_orphans: bool = True) -> None: """Stop and remove resources. Delegates to `docker compose down`. See that command's help for details. Args: destroy_volumes: Remove named volumes and anonymous volumes attached to containers. """ self.invoke( "down", *(["--volumes"] if destroy_volumes else []), *(["--remove-orphans"] if remove_orphans else []), ) def exec(self, service: str, *args: str, detach: bool = False, capture: bool = False, stdin: Optional[str] = None) ‑> subprocess.CompletedProcess-
Execute a one-off command in a service's running container
Delegates to
docker compose exec.Args
service- The service whose container will be used.
command- The command to run.
args- Arguments to pass to the command.
detach- Run the container in the background.
stdin- read STDIN from a string.
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def exec( self, service: str, *args: str, detach: bool = False, capture: bool = False, stdin: Optional[str] = None, ) -> subprocess.CompletedProcess: """Execute a one-off command in a service's running container Delegates to `docker compose exec`. Args: service: The service whose container will be used. command: The command to run. args: Arguments to pass to the command. detach: Run the container in the background. stdin: read STDIN from a string. """ return self.invoke( "exec", *(["--detach"] if detach else []), "-T", service, *( self.compose["services"][service]["entrypoint"] if "entrypoint" in self.compose["services"][service] else [] ), *args, capture=capture, stdin=stdin, ) def invoke(self, *args: str, capture: bool = False, stdin: Optional[str] = None) ‑> subprocess.CompletedProcess-
Invoke
docker composeon the rendered composition.Args
args- The arguments to pass to
docker compose. capture- Whether to capture the child's stdout stream.
input- A string to provide as stdin for the command.
Expand source code Browse git
def invoke( self, *args: str, capture: bool = False, stdin: Optional[str] = None ) -> subprocess.CompletedProcess: """Invoke `docker compose` on the rendered composition. Args: args: The arguments to pass to `docker compose`. capture: Whether to capture the child's stdout stream. input: A string to provide as stdin for the command. """ if not self.silent: print(f"$ docker compose {' '.join(args)}", file=sys.stderr) self.file.seek(0) stdout = None if capture: stdout = subprocess.PIPE try: return subprocess.run( [ "docker", "compose", *(["--log-level=ERROR"] if self.silent else []), f"-f/dev/fd/{self.file.fileno()}", "--project-directory", self.path, *args, ], close_fds=False, check=True, stdout=stdout, input=stdin, text=True, ) except subprocess.CalledProcessError as e: if e.stdout: print(e.stdout) raise UIError(f"running docker compose failed (exit status {e.returncode})") def kill(self, *services: str, signal: str = 'SIGKILL') ‑> None-
Force stop service containers.
Delegates to
docker compose kill. See that command's help for details.Args
services- The names of services in the composition.
signal- The signal to deliver.
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def kill(self, *services: str, signal: str = "SIGKILL") -> None: """Force stop service containers. Delegates to `docker compose kill`. See that command's help for details. Args: services: The names of services in the composition. signal: The signal to deliver. """ self.invoke("kill", f"-s{signal}", *services) def override(self, *services: Service) ‑> Iterator[None]-
Temporarily update the composition with the specified services.
The services must already exist in the composition. They restored to their old definitions when the
withblock ends. Note that the service definition is written in its entirety; i.e., the configuration is not deep merged but replaced wholesale.Lest you are tempted to change this function to allow dynamically injecting new services: do not do this! These services will not be visible to other commands, like
mzcompose run,mzcompose logs, ormzcompose down, which makes debugging or inspecting the composition challenging.Expand source code Browse git
@contextmanager def override(self, *services: "Service") -> Iterator[None]: """Temporarily update the composition with the specified services. The services must already exist in the composition. They restored to their old definitions when the `with` block ends. Note that the service definition is written in its entirety; i.e., the configuration is not deep merged but replaced wholesale. Lest you are tempted to change this function to allow dynamically injecting new services: do not do this! These services will not be visible to other commands, like `mzcompose run`, `mzcompose logs`, or `mzcompose down`, which makes debugging or inspecting the composition challenging. """ # Remember the old composition. old_compose = copy.deepcopy(self.compose) # Update the composition with the new service definitions. deps = self._munge_services([(s.name, cast(dict, s.config)) for s in services]) for service in services: self.compose["services"][service.name] = service.config # Re-acquire dependencies, as the override may have swapped an `image` # config for an `mzbuild` config. deps.acquire() self._write_compose() # Ensure image freshness self.pull_if_variable([service.name for service in services]) try: # Run the next composition. yield finally: # Restore the old composition. self.compose = old_compose self._write_compose() def pause(self, *services: str) ‑> None-
Pause service containers.
Delegates to
docker compose pause. See that command's help for details.Args
services- The names of services in the composition.
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def pause(self, *services: str) -> None: """Pause service containers. Delegates to `docker compose pause`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("pause", *services) def port(self, service: str, private_port: Union[int, str]) ‑> int-
Get the public port for a service's private port.
Delegates to
docker compose port. See that command's help for details.Args
service- The name of a service in the composition.
private_port- A private port exposed by the service.
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def port(self, service: str, private_port: Union[int, str]) -> int: """Get the public port for a service's private port. Delegates to `docker compose port`. See that command's help for details. Args: service: The name of a service in the composition. private_port: A private port exposed by the service. """ proc = self.invoke("port", service, str(private_port), capture=True) if not proc.stdout.strip(): raise UIError( f"service f{service!r} is not exposing port {private_port!r}", hint="is the service running?", ) return int(proc.stdout.split(":")[1]) def pull_if_variable(self, services: List[str]) ‑> None-
Pull fresh service images in case the tag indicates thee underlying image may change over time.
Args
services- List of service names
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def pull_if_variable(self, services: List[str]) -> None: """Pull fresh service images in case the tag indicates thee underlying image may change over time. Args: services: List of service names """ for service in services: if "image" in self.compose["services"][service] and any( self.compose["services"][service]["image"].endswith(tag) for tag in [":latest", ":unstable", ":rolling"] ): self.invoke("pull", service) def rm(self, *services: str, stop: bool = True, destroy_volumes: bool = True) ‑> None-
Remove stopped service containers.
Delegates to
docker compose rm. See that command's help for details.Args
services- The names of services in the composition.
stop- Stop the containers if necessary.
destroy_volumes- Destroy any anonymous volumes associated with the service. Note that this does not destroy any named volumes attached to the service.
Expand source code Browse git
def rm( self, *services: str, stop: bool = True, destroy_volumes: bool = True ) -> None: """Remove stopped service containers. Delegates to `docker compose rm`. See that command's help for details. Args: services: The names of services in the composition. stop: Stop the containers if necessary. destroy_volumes: Destroy any anonymous volumes associated with the service. Note that this does not destroy any named volumes attached to the service. """ self.invoke( "rm", "--force", *(["--stop"] if stop else []), *(["-v"] if destroy_volumes else []), *services, ) def rm_volumes(self, *volumes: str, force: bool = False) ‑> None-
Remove the named volumes.
Args
volumes- The names of volumes in the composition.
force- Whether to force the removal (i.e., don't error if the volume does not exist).
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def rm_volumes(self, *volumes: str, force: bool = False) -> None: """Remove the named volumes. Args: volumes: The names of volumes in the composition. force: Whether to force the removal (i.e., don't error if the volume does not exist). """ volumes = (f"{self.name}_{v}" for v in volumes) spawn.runv( ["docker", "volume", "rm", *(["--force"] if force else []), *volumes] ) def run(self, service: str, *args: str, detach: bool = False, rm: bool = False, env_extra: Dict[str, str] = {}, capture: bool = False, stdin: Optional[str] = None) ‑> subprocess.CompletedProcess-
Run a one-off command in a service.
Delegates to
docker compose run. See that command's help for details. Note that unlikedocker compose run, any services whose definitions have changed are rebuilt (likedocker compose upwould do) before the command is executed.Args
service- The name of a service in the composition.
args- Arguments to pass to the service's entrypoint.
detach- Run the container in the background.
stdin- read STDIN from a string.
env_extra- Additional environment variables to set in the container.
rm- Remove container after run.
capture- Capture the stdout of the
docker composeinvocation.
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def run( self, service: str, *args: str, detach: bool = False, rm: bool = False, env_extra: Dict[str, str] = {}, capture: bool = False, stdin: Optional[str] = None, ) -> subprocess.CompletedProcess: """Run a one-off command in a service. Delegates to `docker compose run`. See that command's help for details. Note that unlike `docker compose run`, any services whose definitions have changed are rebuilt (like `docker compose up` would do) before the command is executed. Args: service: The name of a service in the composition. args: Arguments to pass to the service's entrypoint. detach: Run the container in the background. stdin: read STDIN from a string. env_extra: Additional environment variables to set in the container. rm: Remove container after run. capture: Capture the stdout of the `docker compose` invocation. """ # Restart any dependencies whose definitions have changed. The trick, # taken from Buildkite's Docker Compose plugin, is to run an `up` # command that requests zero instances of the requested service. self.invoke("up", "--detach", "--scale", f"{service}=0", service) return self.invoke( "run", *(f"-e{k}={v}" for k, v in env_extra.items()), *(["--detach"] if detach else []), *(["--rm"] if rm else []), service, *args, capture=capture, stdin=stdin, ) def sleep(self, duration: float) ‑> None-
Sleep for the specified duration in seconds.
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def sleep(self, duration: float) -> None: """Sleep for the specified duration in seconds.""" print(f"Sleeping for {duration} seconds...") time.sleep(duration) def sql(self, sql: str) ‑> None-
Run a batch of SQL statements against the materialized service.
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def sql(self, sql: str) -> None: """Run a batch of SQL statements against the materialized service.""" with self.sql_cursor() as cursor: for statement in sqlparse.split(sql): print(f"> {statement}") cursor.execute(statement) def sql_cursor(self) ‑> pg8000.legacy.Cursor-
Get a cursor to run SQL queries against the materialized service.
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def sql_cursor(self) -> Cursor: """Get a cursor to run SQL queries against the materialized service.""" port = self.default_port("materialized") conn = pg8000.connect(host="localhost", user="materialize", port=port) conn.autocommit = True return conn.cursor() def sql_query(self, sql: str) ‑> Any-
Execute and return results of a SQL query.
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def sql_query(self, sql: str) -> Any: """Execute and return results of a SQL query.""" with self.sql_cursor() as cursor: cursor.execute(sql) return cursor.fetchall() def start_and_wait_for_tcp(self, services: List[str]) ‑> None-
Sequentially start the named services, waiting for eaach to become available via TCP before moving on to the next.
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def start_and_wait_for_tcp(self, services: List[str]) -> None: """Sequentially start the named services, waiting for eaach to become available via TCP before moving on to the next.""" for service in services: self.up(service) for port in self.compose["services"][service].get("ports", []): self.wait_for_tcp(host=service, port=port) def stop(self, *services: str) ‑> None-
Stop the docker containers for the named services.
Delegates to
docker compose stop. See that command's help for details.Args
services- The names of services in the composition.
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def stop(self, *services: str) -> None: """Stop the docker containers for the named services. Delegates to `docker compose stop`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("stop", *services) def test_case(self, name: str) ‑> Iterator[None]-
Execute a test case.
This context manager provides a very lightweight testing framework. If the body of the context manager raises an exception, the test case is considered to have failed; otherwise it is considered to have succeeded. In either case the execution time and status of the test are recorded in
test_results.Example
A simple workflow that executes a table-driven test:
@dataclass class TestCase: name: str files: list[str] test_cases = [ TestCase(name="short", files=["quicktests.td"]), TestCase(name="long", files=["longtest1.td", "longtest2.td"]), ] def workflow_default(c: Composition): for tc in test_cases: with c.test_case(tc.name): c.run("testdrive", *tc.files)Args
name- The name of the test case. Must be unique across the lifetime of a composition.
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@contextmanager def test_case(self, name: str) -> Iterator[None]: """Execute a test case. This context manager provides a very lightweight testing framework. If the body of the context manager raises an exception, the test case is considered to have failed; otherwise it is considered to have succeeded. In either case the execution time and status of the test are recorded in `test_results`. Example: A simple workflow that executes a table-driven test: ``` @dataclass class TestCase: name: str files: list[str] test_cases = [ TestCase(name="short", files=["quicktests.td"]), TestCase(name="long", files=["longtest1.td", "longtest2.td"]), ] def workflow_default(c: Composition): for tc in test_cases: with c.test_case(tc.name): c.run("testdrive", *tc.files) ``` Args: name: The name of the test case. Must be unique across the lifetime of a composition. """ if name in self.test_results: raise UIError(f"test case {name} executed twice") ui.header(f"Running test case {name}") error = None start_time = time.time() try: yield ui.header(f"mzcompose: test case {name} succeeded") except Exception as e: error = str(e) if isinstance(e, UIError): print(f"mzcompose: test case {name} failed: {e}", file=sys.stderr) else: print(f"mzcompose: test case {name} failed:", file=sys.stderr) traceback.print_exc() elapsed = time.time() - start_time self.test_results[name] = Composition.TestResult(elapsed, error) def testdrive(self, input: str, service: str = 'testdrive', persistent: bool = True, args: List[str] = []) ‑> None-
Run a string as a testdrive script.
Args
args- Additional arguments to pass to testdrive
service- Optional name of the testdrive service to use.
input- The string to execute.
persistent- Whether a persistent testdrive container will be used.
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def testdrive( self, input: str, service: str = "testdrive", persistent: bool = True, args: List[str] = [], ) -> None: """Run a string as a testdrive script. Args: args: Additional arguments to pass to testdrive service: Optional name of the testdrive service to use. input: The string to execute. persistent: Whether a persistent testdrive container will be used. """ if persistent: self.exec(service, *args, stdin=input) else: self.run(service, *args, stdin=input) def unpause(self, *services: str) ‑> None-
Unpause service containers
Delegates to
docker compose unpause. See that command's help for details.Args
services- The names of services in the composition.
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def unpause(self, *services: str) -> None: """Unpause service containers Delegates to `docker compose unpause`. See that command's help for details. Args: services: The names of services in the composition. """ self.invoke("unpause", *services) def up(self, *services: str, detach: bool = True, persistent: bool = False) ‑> None-
Build, (re)create, and start the named services.
Delegates to
docker compose up. See that command's help for details.Args
services- The names of services in the composition.
detach- Run containers in the background.
persistent- Replace the container's entrypoint and command with
sleep infinityso that additional commands can be scheduled on the container withComposition.exec().
Expand source code Browse git
def up(self, *services: str, detach: bool = True, persistent: bool = False) -> None: """Build, (re)create, and start the named services. Delegates to `docker compose up`. See that command's help for details. Args: services: The names of services in the composition. detach: Run containers in the background. persistent: Replace the container's entrypoint and command with `sleep infinity` so that additional commands can be scheduled on the container with `Composition.exec`. """ if persistent: old_compose = copy.deepcopy(self.compose) for service in self.compose["services"].values(): service["entrypoint"] = ["sleep", "infinity"] service["command"] = [] self._write_compose() self.invoke("up", *(["--detach"] if detach else []), *services) if persistent: self.compose = old_compose self._write_compose() def wait_for_materialized(self, service: str = 'materialized', *, user: str = 'materialize', dbname: str = 'materialize', host: str = 'localhost', port: Optional[int] = None, timeout_secs: int = 60, query: str = 'SELECT 1', expected: Union[Iterable[Any], Literal['any']] = [[1]], print_result: bool = False) ‑> None-
Like
Workflow.wait_for_postgres, but with Materialize defaults.Expand source code Browse git
def wait_for_materialized( self, service: str = "materialized", *, user: str = "materialize", dbname: str = "materialize", host: str = "localhost", port: Optional[int] = None, timeout_secs: int = 60, query: str = "SELECT 1", expected: Union[Iterable[Any], Literal["any"]] = [[1]], print_result: bool = False, ) -> None: """Like `Workflow.wait_for_postgres`, but with Materialize defaults.""" self.wait_for_postgres( user=user, dbname=dbname, host=host, port=port, timeout_secs=timeout_secs, query=query, expected=expected, print_result=print_result, service=service, ) def wait_for_postgres(self, *, dbname: str = 'postgres', port: Optional[int] = None, host: str = 'localhost', timeout_secs: int = 120, query: str = 'SELECT 1', user: str = 'postgres', password: str = 'postgres', expected: Union[Iterable[Any], Literal['any']] = [[1]], print_result: bool = False, service: str = 'postgres') ‑> None-
Wait for a PostgreSQL service to start.
Args
dbname- the name of the database to wait for
host- the host postgres is listening on
port- the port postgres is listening on
timeout_secs- How long to wait for postgres to be up before failing (Default: 30)
query- The query to execute to ensure that it is running (Default: "Select 1")
user- The chosen user (this is only relevant for postgres)
service- The service that postgres is running as (Default: postgres)
Expand source code Browse git
def wait_for_postgres( self, *, dbname: str = "postgres", port: Optional[int] = None, host: str = "localhost", timeout_secs: int = 120, query: str = "SELECT 1", user: str = "postgres", password: str = "postgres", expected: Union[Iterable[Any], Literal["any"]] = [[1]], print_result: bool = False, service: str = "postgres", ) -> None: """Wait for a PostgreSQL service to start. Args: dbname: the name of the database to wait for host: the host postgres is listening on port: the port postgres is listening on timeout_secs: How long to wait for postgres to be up before failing (Default: 30) query: The query to execute to ensure that it is running (Default: "Select 1") user: The chosen user (this is only relevant for postgres) service: The service that postgres is running as (Default: postgres) """ _wait_for_pg( dbname=dbname, host=host, port=self.port(service, port) if port else self.default_port(service), timeout_secs=timeout_secs, query=query, user=user, password=password, expected=expected, print_result=print_result, ) def wait_for_tcp(self, *, host: str = 'localhost', port: Union[int, str], timeout_secs: int = 240) ‑> None-
Expand source code Browse git
def wait_for_tcp( self, *, host: str = "localhost", port: Union[int, str], timeout_secs: int = 240, ) -> None: if isinstance(port, str): port = int(port.split(":")[0]) ui.progress(f"waiting for {host}:{port}", "C") cmd = f"docker run --rm -t --network {self.name}_default ubuntu:focal-20210723".split() try: _check_tcp(cmd[:], host, port, timeout_secs) except subprocess.CalledProcessError: ui.progress(" error!", finish=True) raise UIError(f"unable to connect to {host}:{port}") else: ui.progress(" success!", finish=True) def workflow(self, name: str, *args: str) ‑> None-
Run a workflow in the composition.
Raises a
KeyErrorif the workflow does not exist.Args
name- The name of the workflow to run.
args- The arguments to pass to the workflow function.
Expand source code Browse git
def workflow(self, name: str, *args: str) -> None: """Run a workflow in the composition. Raises a `KeyError` if the workflow does not exist. Args: name: The name of the workflow to run. args: The arguments to pass to the workflow function. """ ui.header(f"Running workflow {name}") func = self.workflows[name] parser = WorkflowArgumentParser(name, inspect.getdoc(func), list(args)) if len(inspect.signature(func).parameters) > 1: func(self, parser) else: # If the workflow doesn't have an `args` parameter, parse them here # with an empty parser to reject bogus arguments and to handle the # trivial help message. parser.parse_args() func(self)
class LintError (file: pathlib.Path, message: str)-
Expand source code Browse git
class LintError: def __init__(self, file: Path, message: str): self.file = file self.message = message def __str__(self) -> str: return f"{os.path.relpath(self.file)}: {self.message}" def __lt__(self, other: "LintError") -> bool: return (self.file, self.message) < (other.file, other.message) class Service (name: str, config: ServiceConfig)-
A Docker Compose service in a
Composition.Attributes
name- The name of the service.
config- The definition of the service.
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class Service: """A Docker Compose service in a `Composition`. Attributes: name: The name of the service. config: The definition of the service. """ def __init__(self, name: str, config: ServiceConfig) -> None: self.name = name self.config = configSubclasses
class ServiceConfig (*args, **kwargs)-
The definition of a service in Docker Compose.
This object corresponds directly to the YAML definition in a docker-compose.yml file, plus two mzcompose-specific attributes. Full details are available in Services top-level element chapter of the Compose Specification.
Expand source code Browse git
class ServiceConfig(TypedDict, total=False): """The definition of a service in Docker Compose. This object corresponds directly to the YAML definition in a docker-compose.yml file, plus two mzcompose-specific attributes. Full details are available in [Services top-level element][ref] chapter of the Compose Specification. [ref]: https://github.com/compose-spec/compose-spec/blob/master/spec.md#services-top-level-element """ mzbuild: str """The name of an mzbuild image to dynamically acquire before invoking Docker Compose. This is a mzcompose-extension to Docker Compose. The image must exist in the repository. If `mzbuild` is set, neither `build` nor `image` should be set. """ propagate_uid_gid: bool """Request that the Docker image be run with the user ID and group ID of the host user. This is an mzcompose extension to Docker Compose. It is equivalent to passing `--user $(id -u):$(id -g)` to `docker run`. The defualt is `False`. """ allow_host_ports: bool """Allow the service to map host ports in its `ports` configuration. This option is intended only for compositions that are meant to be run as background services in developer environments. Compositions that are isolated tests of Materialize should *not* enable this option, as it leads to unnecessary conflicts between compositions. Compositions that publish the same host port cannot be run concurrently. Instead, users should use the `mzcompose port` command to discover the ephemeral host port mapped to the desired container port, or to use `mzcompose up --preserve-ports`, which publishes all container ports as host ports on a per-invocation basis. """ image: str """The name and tag of an image on Docker Hub.""" hostname: str """The hostname to use. By default, the name of the service is used as the hostname. """ entrypoint: List[str] """Override the entrypoint specified in the image.""" command: str """Override the command specified in the image.""" init: bool """Whether to run an init process in the container.""" ports: Sequence[Union[int, str]] """Service ports to expose to the host.""" environment: List[str] """Additional environment variables to set. Each entry must be in the form `NAME=VALUE`. TODO(benesch): this should accept a `Dict[str, str]` instead. """ depends_on: List[str] """The list of other services that must be started before this one.""" volumes: List[str] """Volumes to attach to the service.""" networks: Dict[str, Dict[str, List[str]]] """Additional networks to join. TODO(benesch): this should use a nested TypedDict. """ deploy: Dict[str, Dict[str, Dict[str, str]]] """Additional deployment configuration, like resource limits. TODO(benesch): this should use a nested TypedDict. """ ulimits: Dict[str, Any] """Override the default ulimits for a container.""" working_dir: str """Overrides the container's working directory."""Ancestors
- builtins.dict
Class variables
var allow_host_ports : bool-
Allow the service to map host ports in its
portsconfiguration.This option is intended only for compositions that are meant to be run as background services in developer environments. Compositions that are isolated tests of Materialize should not enable this option, as it leads to unnecessary conflicts between compositions. Compositions that publish the same host port cannot be run concurrently. Instead, users should use the
mzcompose portcommand to discover the ephemeral host port mapped to the desired container port, or to usemzcompose up --preserve-ports, which publishes all container ports as host ports on a per-invocation basis. var command : str-
Override the command specified in the image.
var depends_on : List[str]-
The list of other services that must be started before this one.
var deploy : Dict[str, Dict[str, Dict[str, str]]]-
Additional deployment configuration, like resource limits.
TODO(benesch): this should use a nested TypedDict.
var entrypoint : List[str]-
Override the entrypoint specified in the image.
var environment : List[str]-
Additional environment variables to set.
Each entry must be in the form
NAME=VALUE.TODO(benesch): this should accept a
Dict[str, str]instead. var hostname : str-
The hostname to use.
By default, the name of the service is used as the hostname.
var image : str-
The name and tag of an image on Docker Hub.
var init : bool-
Whether to run an init process in the container.
var mzbuild : str-
The name of an mzbuild image to dynamically acquire before invoking Docker Compose.
This is a mzcompose-extension to Docker Compose. The image must exist in the repository. If
mzbuildis set, neitherbuildnorimageshould be set. var networks : Dict[str, Dict[str, List[str]]]-
Additional networks to join.
TODO(benesch): this should use a nested TypedDict.
var ports : Sequence[Union[int, str]]-
Service ports to expose to the host.
var propagate_uid_gid : bool-
Request that the Docker image be run with the user ID and group ID of the host user.
This is an mzcompose extension to Docker Compose. It is equivalent to passing
--user $(id -u):$(id -g)todocker run. The defualt isFalse. var ulimits : Dict[str, Any]-
Override the default ulimits for a container.
var volumes : List[str]-
Volumes to attach to the service.
var working_dir : str-
Overrides the container's working directory.
class UnknownCompositionError (name: str)-
The specified composition was unknown.
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class UnknownCompositionError(UIError): """The specified composition was unknown.""" def __init__(self, name: str): super().__init__(f"unknown composition {name!r}")Ancestors
- UIError
- builtins.Exception
- builtins.BaseException
Inherited members
class WorkflowArgumentParser (name: str, description: Optional[str], args: List[str])-
An argument parser provided to a workflow in a
Composition.You can call
add_argumentand other methods on this argument parser like usual. When you are ready to parse arguments, callparse_argsorparse_known_argslike usual; the argument parser will automatically use the arguments that the user provided to the workflow.Expand source code Browse git
class WorkflowArgumentParser(argparse.ArgumentParser): """An argument parser provided to a workflow in a `Composition`. You can call `add_argument` and other methods on this argument parser like usual. When you are ready to parse arguments, call `parse_args` or `parse_known_args` like usual; the argument parser will automatically use the arguments that the user provided to the workflow. """ def __init__(self, name: str, description: Optional[str], args: List[str]): self.args = args super().__init__(prog=f"mzcompose run {name}", description=description) def parse_known_args( self, args: Optional[Sequence[str]] = None, namespace: Optional[argparse.Namespace] = None, ) -> Tuple[argparse.Namespace, List[str]]: if args is None: args = self.args return super().parse_known_args(args, namespace)Ancestors
- argparse.ArgumentParser
- argparse._AttributeHolder
- argparse._ActionsContainer
Methods
def parse_known_args(self, args: Optional[Sequence[str]] = None, namespace: Optional[argparse.Namespace] = None) ‑> Tuple[argparse.Namespace, List[str]]-
Expand source code Browse git
def parse_known_args( self, args: Optional[Sequence[str]] = None, namespace: Optional[argparse.Namespace] = None, ) -> Tuple[argparse.Namespace, List[str]]: if args is None: args = self.args return super().parse_known_args(args, namespace)