1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585 586 587 588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628 629 630 631 632 633 634 635 636 637 638 639 640 641 642 643 644 645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741 742 743 744 745 746 747 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862 863 864 865 866 867 868 869 870 871 872 873 874 875 876 877 878 879 880 881 882 883 884 885
use super::{Format, FormatEvent, FormatFields, FormatTime, Writer};
use crate::{
field::{RecordFields, VisitOutput},
fmt::{
fmt_layer::{FmtContext, FormattedFields},
writer::WriteAdaptor,
},
registry::LookupSpan,
};
use serde::ser::{SerializeMap, Serializer as _};
use serde_json::Serializer;
use std::{
collections::BTreeMap,
fmt::{self, Write},
};
use tracing_core::{
field::{self, Field},
span::Record,
Event, Subscriber,
};
use tracing_serde::AsSerde;
#[cfg(feature = "tracing-log")]
use tracing_log::NormalizeEvent;
/// Marker for [`Format`] that indicates that the newline-delimited JSON log
/// format should be used.
///
/// This formatter is intended for production use with systems where structured
/// logs are consumed as JSON by analysis and viewing tools. The JSON output is
/// not optimized for human readability; instead, it should be pretty-printed
/// using external JSON tools such as `jq`, or using a JSON log viewer.
///
/// # Example Output
///
/// <pre><font color="#4E9A06"><b>:;</b></font> <font color="#4E9A06">cargo</font> run --example fmt-json
/// <font color="#4E9A06"><b> Finished</b></font> dev [unoptimized + debuginfo] target(s) in 0.08s
/// <font color="#4E9A06"><b> Running</b></font> `target/debug/examples/fmt-json`
/// {"timestamp":"2022-02-15T18:47:10.821315Z","level":"INFO","fields":{"message":"preparing to shave yaks","number_of_yaks":3},"target":"fmt_json"}
/// {"timestamp":"2022-02-15T18:47:10.821422Z","level":"INFO","fields":{"message":"shaving yaks"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.821495Z","level":"TRACE","fields":{"message":"hello! I'm gonna shave a yak","excitement":"yay!"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":1,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.821546Z","level":"TRACE","fields":{"message":"yak shaved successfully"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":1,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.821598Z","level":"DEBUG","fields":{"yak":1,"shaved":true},"target":"yak_events","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.821637Z","level":"TRACE","fields":{"yaks_shaved":1},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.821684Z","level":"TRACE","fields":{"message":"hello! I'm gonna shave a yak","excitement":"yay!"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":2,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.821727Z","level":"TRACE","fields":{"message":"yak shaved successfully"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":2,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.821773Z","level":"DEBUG","fields":{"yak":2,"shaved":true},"target":"yak_events","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.821806Z","level":"TRACE","fields":{"yaks_shaved":2},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.821909Z","level":"TRACE","fields":{"message":"hello! I'm gonna shave a yak","excitement":"yay!"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":3,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.821956Z","level":"WARN","fields":{"message":"could not locate yak"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"},{"yak":3,"name":"shave"}]}
/// {"timestamp":"2022-02-15T18:47:10.822006Z","level":"DEBUG","fields":{"yak":3,"shaved":false},"target":"yak_events","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.822041Z","level":"ERROR","fields":{"message":"failed to shave yak","yak":3,"error":"missing yak"},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.822079Z","level":"TRACE","fields":{"yaks_shaved":2},"target":"fmt_json::yak_shave","spans":[{"yaks":3,"name":"shaving_yaks"}]}
/// {"timestamp":"2022-02-15T18:47:10.822117Z","level":"INFO","fields":{"message":"yak shaving completed","all_yaks_shaved":false},"target":"fmt_json"}
/// </pre>
///
/// # Options
///
/// This formatter exposes additional options to configure the structure of the
/// output JSON objects:
///
/// - [`Json::flatten_event`] can be used to enable flattening event fields into
/// the root
/// - [`Json::with_current_span`] can be used to control logging of the current
/// span
/// - [`Json::with_span_list`] can be used to control logging of the span list
/// object.
///
/// By default, event fields are not flattened, and both current span and span
/// list are logged.
///
/// # Valuable Support
///
/// Experimental support is available for using the [`valuable`] crate to record
/// user-defined values as structured JSON. When the ["valuable" unstable
/// feature][unstable] is enabled, types implementing [`valuable::Valuable`] will
/// be recorded as structured JSON, rather than
/// using their [`std::fmt::Debug`] implementations.
///
/// **Note**: This is an experimental feature. [Unstable features][unstable]
/// must be enabled in order to use `valuable` support.
///
/// [`Json::flatten_event`]: Json::flatten_event()
/// [`Json::with_current_span`]: Json::with_current_span()
/// [`Json::with_span_list`]: Json::with_span_list()
/// [`valuable`]: https://crates.io/crates/valuable
/// [unstable]: crate#unstable-features
/// [`valuable::Valuable`]: https://docs.rs/valuable/latest/valuable/trait.Valuable.html
#[derive(Debug, Copy, Clone, Eq, PartialEq)]
pub struct Json {
pub(crate) flatten_event: bool,
pub(crate) display_current_span: bool,
pub(crate) display_span_list: bool,
}
impl Json {
/// If set to `true` event metadata will be flattened into the root object.
pub fn flatten_event(&mut self, flatten_event: bool) {
self.flatten_event = flatten_event;
}
/// If set to `false`, formatted events won't contain a field for the current span.
pub fn with_current_span(&mut self, display_current_span: bool) {
self.display_current_span = display_current_span;
}
/// If set to `false`, formatted events won't contain a list of all currently
/// entered spans. Spans are logged in a list from root to leaf.
pub fn with_span_list(&mut self, display_span_list: bool) {
self.display_span_list = display_span_list;
}
}
struct SerializableContext<'a, 'b, Span, N>(
&'b crate::layer::Context<'a, Span>,
std::marker::PhantomData<N>,
)
where
Span: Subscriber + for<'lookup> crate::registry::LookupSpan<'lookup>,
N: for<'writer> FormatFields<'writer> + 'static;
impl<'a, 'b, Span, N> serde::ser::Serialize for SerializableContext<'a, 'b, Span, N>
where
Span: Subscriber + for<'lookup> crate::registry::LookupSpan<'lookup>,
N: for<'writer> FormatFields<'writer> + 'static,
{
fn serialize<Ser>(&self, serializer_o: Ser) -> Result<Ser::Ok, Ser::Error>
where
Ser: serde::ser::Serializer,
{
use serde::ser::SerializeSeq;
let mut serializer = serializer_o.serialize_seq(None)?;
if let Some(leaf_span) = self.0.lookup_current() {
for span in leaf_span.scope().from_root() {
serializer.serialize_element(&SerializableSpan(&span, self.1))?;
}
}
serializer.end()
}
}
struct SerializableSpan<'a, 'b, Span, N>(
&'b crate::registry::SpanRef<'a, Span>,
std::marker::PhantomData<N>,
)
where
Span: for<'lookup> crate::registry::LookupSpan<'lookup>,
N: for<'writer> FormatFields<'writer> + 'static;
impl<'a, 'b, Span, N> serde::ser::Serialize for SerializableSpan<'a, 'b, Span, N>
where
Span: for<'lookup> crate::registry::LookupSpan<'lookup>,
N: for<'writer> FormatFields<'writer> + 'static,
{
fn serialize<Ser>(&self, serializer: Ser) -> Result<Ser::Ok, Ser::Error>
where
Ser: serde::ser::Serializer,
{
let mut serializer = serializer.serialize_map(None)?;
let ext = self.0.extensions();
let data = ext
.get::<FormattedFields<N>>()
.expect("Unable to find FormattedFields in extensions; this is a bug");
// TODO: let's _not_ do this, but this resolves
// https://github.com/tokio-rs/tracing/issues/391.
// We should probably rework this to use a `serde_json::Value` or something
// similar in a JSON-specific layer, but I'd (david)
// rather have a uglier fix now rather than shipping broken JSON.
match serde_json::from_str::<serde_json::Value>(data) {
Ok(serde_json::Value::Object(fields)) => {
for field in fields {
serializer.serialize_entry(&field.0, &field.1)?;
}
}
// We have fields for this span which are valid JSON but not an object.
// This is probably a bug, so panic if we're in debug mode
Ok(_) if cfg!(debug_assertions) => panic!(
"span '{}' had malformed fields! this is a bug.\n error: invalid JSON object\n fields: {:?}",
self.0.metadata().name(),
data
),
// If we *aren't* in debug mode, it's probably best not to
// crash the program, let's log the field found but also an
// message saying it's type is invalid
Ok(value) => {
serializer.serialize_entry("field", &value)?;
serializer.serialize_entry("field_error", "field was no a valid object")?
}
// We have previously recorded fields for this span
// should be valid JSON. However, they appear to *not*
// be valid JSON. This is almost certainly a bug, so
// panic if we're in debug mode
Err(e) if cfg!(debug_assertions) => panic!(
"span '{}' had malformed fields! this is a bug.\n error: {}\n fields: {:?}",
self.0.metadata().name(),
e,
data
),
// If we *aren't* in debug mode, it's probably best not
// crash the program, but let's at least make sure it's clear
// that the fields are not supposed to be missing.
Err(e) => serializer.serialize_entry("field_error", &format!("{}", e))?,
};
serializer.serialize_entry("name", self.0.metadata().name())?;
serializer.end()
}
}
impl<S, N, T> FormatEvent<S, N> for Format<Json, T>
where
S: Subscriber + for<'lookup> LookupSpan<'lookup>,
N: for<'writer> FormatFields<'writer> + 'static,
T: FormatTime,
{
fn format_event(
&self,
ctx: &FmtContext<'_, S, N>,
mut writer: Writer<'_>,
event: &Event<'_>,
) -> fmt::Result
where
S: Subscriber + for<'a> LookupSpan<'a>,
{
let mut timestamp = String::new();
self.timer.format_time(&mut Writer::new(&mut timestamp))?;
#[cfg(feature = "tracing-log")]
let normalized_meta = event.normalized_metadata();
#[cfg(feature = "tracing-log")]
let meta = normalized_meta.as_ref().unwrap_or_else(|| event.metadata());
#[cfg(not(feature = "tracing-log"))]
let meta = event.metadata();
let mut visit = || {
let mut serializer = Serializer::new(WriteAdaptor::new(&mut writer));
let mut serializer = serializer.serialize_map(None)?;
if self.display_timestamp {
serializer.serialize_entry("timestamp", ×tamp)?;
}
if self.display_level {
serializer.serialize_entry("level", &meta.level().as_serde())?;
}
let format_field_marker: std::marker::PhantomData<N> = std::marker::PhantomData;
let current_span = if self.format.display_current_span || self.format.display_span_list
{
event
.parent()
.and_then(|id| ctx.span(id))
.or_else(|| ctx.lookup_current())
} else {
None
};
if self.format.flatten_event {
let mut visitor = tracing_serde::SerdeMapVisitor::new(serializer);
event.record(&mut visitor);
serializer = visitor.take_serializer()?;
} else {
use tracing_serde::fields::AsMap;
serializer.serialize_entry("fields", &event.field_map())?;
};
if self.display_target {
serializer.serialize_entry("target", meta.target())?;
}
if self.display_filename {
if let Some(filename) = meta.file() {
serializer.serialize_entry("filename", filename)?;
}
}
if self.display_line_number {
if let Some(line_number) = meta.line() {
serializer.serialize_entry("line_number", &line_number)?;
}
}
if self.format.display_current_span {
if let Some(ref span) = current_span {
serializer
.serialize_entry("span", &SerializableSpan(span, format_field_marker))
.unwrap_or(());
}
}
if self.format.display_span_list && current_span.is_some() {
serializer.serialize_entry(
"spans",
&SerializableContext(&ctx.ctx, format_field_marker),
)?;
}
if self.display_thread_name {
let current_thread = std::thread::current();
match current_thread.name() {
Some(name) => {
serializer.serialize_entry("threadName", name)?;
}
// fall-back to thread id when name is absent and ids are not enabled
None if !self.display_thread_id => {
serializer
.serialize_entry("threadName", &format!("{:?}", current_thread.id()))?;
}
_ => {}
}
}
if self.display_thread_id {
serializer
.serialize_entry("threadId", &format!("{:?}", std::thread::current().id()))?;
}
serializer.end()
};
visit().map_err(|_| fmt::Error)?;
writeln!(writer)
}
}
impl Default for Json {
fn default() -> Json {
Json {
flatten_event: false,
display_current_span: true,
display_span_list: true,
}
}
}
/// The JSON [`FormatFields`] implementation.
///
#[derive(Debug)]
pub struct JsonFields {
// reserve the ability to add fields to this without causing a breaking
// change in the future.
_private: (),
}
impl JsonFields {
/// Returns a new JSON [`FormatFields`] implementation.
///
pub fn new() -> Self {
Self { _private: () }
}
}
impl Default for JsonFields {
fn default() -> Self {
Self::new()
}
}
impl<'a> FormatFields<'a> for JsonFields {
/// Format the provided `fields` to the provided `writer`, returning a result.
fn format_fields<R: RecordFields>(&self, mut writer: Writer<'_>, fields: R) -> fmt::Result {
let mut v = JsonVisitor::new(&mut writer);
fields.record(&mut v);
v.finish()
}
/// Record additional field(s) on an existing span.
///
/// By default, this appends a space to the current set of fields if it is
/// non-empty, and then calls `self.format_fields`. If different behavior is
/// required, the default implementation of this method can be overridden.
fn add_fields(
&self,
current: &'a mut FormattedFields<Self>,
fields: &Record<'_>,
) -> fmt::Result {
if current.is_empty() {
// If there are no previously recorded fields, we can just reuse the
// existing string.
let mut writer = current.as_writer();
let mut v = JsonVisitor::new(&mut writer);
fields.record(&mut v);
v.finish()?;
return Ok(());
}
// If fields were previously recorded on this span, we need to parse
// the current set of fields as JSON, add the new fields, and
// re-serialize them. Otherwise, if we just appended the new fields
// to a previously serialized JSON object, we would end up with
// malformed JSON.
//
// XXX(eliza): this is far from efficient, but unfortunately, it is
// necessary as long as the JSON formatter is implemented on top of
// an interface that stores all formatted fields as strings.
//
// We should consider reimplementing the JSON formatter as a
// separate layer, rather than a formatter for the `fmt` layer —
// then, we could store fields as JSON values, and add to them
// without having to parse and re-serialize.
let mut new = String::new();
let map: BTreeMap<&'_ str, serde_json::Value> =
serde_json::from_str(current).map_err(|_| fmt::Error)?;
let mut v = JsonVisitor::new(&mut new);
v.values = map;
fields.record(&mut v);
v.finish()?;
current.fields = new;
Ok(())
}
}
/// The [visitor] produced by [`JsonFields`]'s [`MakeVisitor`] implementation.
///
/// [visitor]: crate::field::Visit
/// [`MakeVisitor`]: crate::field::MakeVisitor
pub struct JsonVisitor<'a> {
values: BTreeMap<&'a str, serde_json::Value>,
writer: &'a mut dyn Write,
}
impl<'a> fmt::Debug for JsonVisitor<'a> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
f.write_fmt(format_args!("JsonVisitor {{ values: {:?} }}", self.values))
}
}
impl<'a> JsonVisitor<'a> {
/// Returns a new default visitor that formats to the provided `writer`.
///
/// # Arguments
/// - `writer`: the writer to format to.
/// - `is_empty`: whether or not any fields have been previously written to
/// that writer.
pub fn new(writer: &'a mut dyn Write) -> Self {
Self {
values: BTreeMap::new(),
writer,
}
}
}
impl<'a> crate::field::VisitFmt for JsonVisitor<'a> {
fn writer(&mut self) -> &mut dyn fmt::Write {
self.writer
}
}
impl<'a> crate::field::VisitOutput<fmt::Result> for JsonVisitor<'a> {
fn finish(self) -> fmt::Result {
let inner = || {
let mut serializer = Serializer::new(WriteAdaptor::new(self.writer));
let mut ser_map = serializer.serialize_map(None)?;
for (k, v) in self.values {
ser_map.serialize_entry(k, &v)?;
}
ser_map.end()
};
if inner().is_err() {
Err(fmt::Error)
} else {
Ok(())
}
}
}
impl<'a> field::Visit for JsonVisitor<'a> {
#[cfg(all(tracing_unstable, feature = "valuable"))]
fn record_value(&mut self, field: &Field, value: valuable_crate::Value<'_>) {
let value = match serde_json::to_value(valuable_serde::Serializable::new(value)) {
Ok(value) => value,
Err(_e) => {
#[cfg(debug_assertions)]
unreachable!(
"`valuable::Valuable` implementations should always serialize \
successfully, but an error occurred: {}",
_e,
);
#[cfg(not(debug_assertions))]
return;
}
};
self.values.insert(field.name(), value);
}
/// Visit a double precision floating point value.
fn record_f64(&mut self, field: &Field, value: f64) {
self.values
.insert(field.name(), serde_json::Value::from(value));
}
/// Visit a signed 64-bit integer value.
fn record_i64(&mut self, field: &Field, value: i64) {
self.values
.insert(field.name(), serde_json::Value::from(value));
}
/// Visit an unsigned 64-bit integer value.
fn record_u64(&mut self, field: &Field, value: u64) {
self.values
.insert(field.name(), serde_json::Value::from(value));
}
/// Visit a boolean value.
fn record_bool(&mut self, field: &Field, value: bool) {
self.values
.insert(field.name(), serde_json::Value::from(value));
}
/// Visit a string value.
fn record_str(&mut self, field: &Field, value: &str) {
self.values
.insert(field.name(), serde_json::Value::from(value));
}
fn record_debug(&mut self, field: &Field, value: &dyn fmt::Debug) {
match field.name() {
// Skip fields that are actually log metadata that have already been handled
#[cfg(feature = "tracing-log")]
name if name.starts_with("log.") => (),
name if name.starts_with("r#") => {
self.values
.insert(&name[2..], serde_json::Value::from(format!("{:?}", value)));
}
name => {
self.values
.insert(name, serde_json::Value::from(format!("{:?}", value)));
}
};
}
}
#[cfg(test)]
mod test {
use super::*;
use crate::fmt::{format::FmtSpan, test::MockMakeWriter, time::FormatTime, SubscriberBuilder};
use tracing::{self, subscriber::with_default};
use std::fmt;
use std::path::Path;
struct MockTime;
impl FormatTime for MockTime {
fn format_time(&self, w: &mut Writer<'_>) -> fmt::Result {
write!(w, "fake time")
}
}
fn subscriber() -> SubscriberBuilder<JsonFields, Format<Json>> {
SubscriberBuilder::default().json()
}
#[test]
fn json() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_span_list(true);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_filename() {
let current_path = Path::new("tracing-subscriber")
.join("src")
.join("fmt")
.join("format")
.join("json.rs")
.to_str()
.expect("path must be valid unicode")
// escape windows backslashes
.replace('\\', "\\\\");
let expected =
&format!("{}{}{}",
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"filename\":\"",
current_path,
"\",\"fields\":{\"message\":\"some json test\"}}\n");
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_file(true)
.with_span_list(true);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_line_number() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"line_number\":42,\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_line_number(true)
.with_span_list(true);
test_json_with_line_number(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_flattened_event() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"message\":\"some json test\"}\n";
let subscriber = subscriber()
.flatten_event(true)
.with_current_span(true)
.with_span_list(true);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_disabled_current_span_event() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(false)
.with_span_list(true);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_disabled_span_list_event() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":42,\"name\":\"json_span\",\"number\":3},\"target\":\"tracing_subscriber::fmt::format::json::test\",\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_span_list(false);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_nested_span() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"span\":{\"answer\":43,\"name\":\"nested_json_span\",\"number\":4},\"spans\":[{\"answer\":42,\"name\":\"json_span\",\"number\":3},{\"answer\":43,\"name\":\"nested_json_span\",\"number\":4}],\"target\":\"tracing_subscriber::fmt::format::json::test\",\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_span_list(true);
test_json(expected, subscriber, || {
let span = tracing::span!(tracing::Level::INFO, "json_span", answer = 42, number = 3);
let _guard = span.enter();
let span = tracing::span!(
tracing::Level::INFO,
"nested_json_span",
answer = 43,
number = 4
);
let _guard = span.enter();
tracing::info!("some json test");
});
}
#[test]
fn json_no_span() {
let expected =
"{\"timestamp\":\"fake time\",\"level\":\"INFO\",\"target\":\"tracing_subscriber::fmt::format::json::test\",\"fields\":{\"message\":\"some json test\"}}\n";
let subscriber = subscriber()
.flatten_event(false)
.with_current_span(true)
.with_span_list(true);
test_json(expected, subscriber, || {
tracing::info!("some json test");
});
}
#[test]
fn record_works() {
// This test reproduces issue #707, where using `Span::record` causes
// any events inside the span to be ignored.
let make_writer = MockMakeWriter::default();
let subscriber = crate::fmt()
.json()
.with_writer(make_writer.clone())
.finish();
with_default(subscriber, || {
tracing::info!("an event outside the root span");
assert_eq!(
parse_as_json(&make_writer)["fields"]["message"],
"an event outside the root span"
);
let span = tracing::info_span!("the span", na = tracing::field::Empty);
span.record("na", "value");
let _enter = span.enter();
tracing::info!("an event inside the root span");
assert_eq!(
parse_as_json(&make_writer)["fields"]["message"],
"an event inside the root span"
);
});
}
#[test]
fn json_span_event_show_correct_context() {
let buffer = MockMakeWriter::default();
let subscriber = subscriber()
.with_writer(buffer.clone())
.flatten_event(false)
.with_current_span(true)
.with_span_list(false)
.with_span_events(FmtSpan::FULL)
.finish();
with_default(subscriber, || {
let context = "parent";
let parent_span = tracing::info_span!("parent_span", context);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "new");
assert_eq!(event["span"]["context"], "parent");
let _parent_enter = parent_span.enter();
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "enter");
assert_eq!(event["span"]["context"], "parent");
let context = "child";
let child_span = tracing::info_span!("child_span", context);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "new");
assert_eq!(event["span"]["context"], "child");
let _child_enter = child_span.enter();
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "enter");
assert_eq!(event["span"]["context"], "child");
drop(_child_enter);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "exit");
assert_eq!(event["span"]["context"], "child");
drop(child_span);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "close");
assert_eq!(event["span"]["context"], "child");
drop(_parent_enter);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "exit");
assert_eq!(event["span"]["context"], "parent");
drop(parent_span);
let event = parse_as_json(&buffer);
assert_eq!(event["fields"]["message"], "close");
assert_eq!(event["span"]["context"], "parent");
});
}
#[test]
fn json_span_event_with_no_fields() {
// Check span events serialize correctly.
// Discussion: https://github.com/tokio-rs/tracing/issues/829#issuecomment-661984255
let buffer = MockMakeWriter::default();
let subscriber = subscriber()
.with_writer(buffer.clone())
.flatten_event(false)
.with_current_span(false)
.with_span_list(false)
.with_span_events(FmtSpan::FULL)
.finish();
with_default(subscriber, || {
let span = tracing::info_span!("valid_json");
assert_eq!(parse_as_json(&buffer)["fields"]["message"], "new");
let _enter = span.enter();
assert_eq!(parse_as_json(&buffer)["fields"]["message"], "enter");
drop(_enter);
assert_eq!(parse_as_json(&buffer)["fields"]["message"], "exit");
drop(span);
assert_eq!(parse_as_json(&buffer)["fields"]["message"], "close");
});
}
fn parse_as_json(buffer: &MockMakeWriter) -> serde_json::Value {
let buf = String::from_utf8(buffer.buf().to_vec()).unwrap();
let json = buf
.lines()
.last()
.expect("expected at least one line to be written!");
match serde_json::from_str(json) {
Ok(v) => v,
Err(e) => panic!(
"assertion failed: JSON shouldn't be malformed\n error: {}\n json: {}",
e, json
),
}
}
fn test_json<T>(
expected: &str,
builder: crate::fmt::SubscriberBuilder<JsonFields, Format<Json>>,
producer: impl FnOnce() -> T,
) {
let make_writer = MockMakeWriter::default();
let subscriber = builder
.with_writer(make_writer.clone())
.with_timer(MockTime)
.finish();
with_default(subscriber, producer);
let buf = make_writer.buf();
let actual = std::str::from_utf8(&buf[..]).unwrap();
assert_eq!(
serde_json::from_str::<std::collections::HashMap<&str, serde_json::Value>>(expected)
.unwrap(),
serde_json::from_str(actual).unwrap()
);
}
fn test_json_with_line_number<T>(
expected: &str,
builder: crate::fmt::SubscriberBuilder<JsonFields, Format<Json>>,
producer: impl FnOnce() -> T,
) {
let make_writer = MockMakeWriter::default();
let subscriber = builder
.with_writer(make_writer.clone())
.with_timer(MockTime)
.finish();
with_default(subscriber, producer);
let buf = make_writer.buf();
let actual = std::str::from_utf8(&buf[..]).unwrap();
let mut expected =
serde_json::from_str::<std::collections::HashMap<&str, serde_json::Value>>(expected)
.unwrap();
let expect_line_number = expected.remove("line_number").is_some();
let mut actual: std::collections::HashMap<&str, serde_json::Value> =
serde_json::from_str(actual).unwrap();
let line_number = actual.remove("line_number");
if expect_line_number {
assert_eq!(line_number.map(|x| x.is_number()), Some(true));
} else {
assert!(line_number.is_none());
}
assert_eq!(actual, expected);
}
}