Expand description

Coordinates client requests with the dataflow layer.

This crate hosts the “coordinator”, an object which sits at the center of the system and coordinates communication between the various components. Responsibilities of the coordinator include:

  • Launching the dataflow workers.
  • Periodically allowing the dataflow workers to compact existing data.
  • Executing SQL queries from clients by parsing and planning them, sending the plans to the dataflow layer, and then streaming the results back to the client.
  • Assigning timestamps to incoming source data.

The main interface to the coordinator is Client. To start a coordinator, use the serve function.


Persistent metadata storage for the coordinator.

client 🔒
command 🔒
coord 🔒

Translation of SQL commands into timestamped Controller commands.

error 🔒

Per-connection configuration parameters and state.

tail 🔒

Implementations around supporting the TAIL protocol with the dataflow layer

util 🔒


coord_bail 🔒


A coordinator client.

Configures a coordinator.

A coordinator client that is bound to a connection.

A handle to a running coordinator.

A coordinator client that is bound to a connection.


The state of a cancellation request.

Errors that can occur in the coordinator.

The response from a Peek, with row multiplicities represented in unary.


Serves the coordinator based on the provided configuration.

Type Definitions