1# Tracing Examples 2 3This directory contains a collection of examples that demonstrate the use of the 4`tracing` ecosystem: 5 6- **tracing**: 7 + `counters`: Implements a very simple metrics system to demonstrate how 8 subscribers can consume field values as typed data. 9 + `sloggish`: A demo `Subscriber` implementation that mimics the output of 10 `slog-term`'s `Compact` formatter. 11- **tracing-attributes**: 12 + `attrs-basic`: A simple example of the `#[instrument]` attribute. 13 + `attrs-literal-field-names`: Demonstrates using literal field names rather 14 than rust tokens.. 15 + `attrs-args`: An example implementing a simple recursive calculation of 16 Fibonacci numbers, to demonstrate how the `#[instrument]` attribute can 17 record function arguments. 18- **tracing-subscriber**: 19 + `fmt`: Demonstrates the use of the [`fmt`] module in `tracing-subscriber`, 20 which provides a subscriber implementation that logs traces to the console. 21 This example uses the default formatter ([`format::Full`]). 22 + `fmt-stderr`: Demonstrates overriding the output stream used by the `fmt` 23 subscriber. 24 + `fmt-pretty`: Demonstrates the output of the [`format::Pretty`] formatter in 25 [`tracing-subscriber::fmt`][`fmt`]. 26 + `fmt-compact`: Demonstrates the output of the [`format::Compact`] formatter in 27 [`tracing-subscriber::fmt`][`fmt`]. 28 + `fmt-json`: Demonstrates the output of the [`format::Json`] formatter in 29 [`tracing-subscriber::fmt`][`fmt`]. 30 + `fmt-custom-field`: Demonstrates overriding how the [`fmt`] subscriber formats 31 fields on spans and events. 32 + `fmt-custom-event`: Demonstrates overriding how the [`fmt`] subscriber formats 33 events. 34 + `fmt-multiple-writers`: demonstrates how [`fmt::Layer`] can write 35 to multiple destinations (in this instance, stdout and a file) simultaneously. 36 + `fmt-source-locations`: demonstrates displaying source code locations 37 with [`fmt::Layer`]. 38 + `subscriber-filter`: Demonstrates the `tracing-subscriber::filter` module, 39 which provides a layer which adds configurable filtering to a subscriber 40 implementation. 41 + `tower-load`: Demonstrates how dynamically reloadable filters can be used to 42 debug a server under load in production. 43 + `journald`: Demonstrates how to use [`fmt`] and `journald` layers to output to 44 both the terminal and the system journal. 45 + `toggle-layers` : Demonstrates how Layers can be wrapped with an `Option` allowing 46 them to be dynamically toggled. 47- **tracing-futures**: 48 + `spawny-thing`: Demonstrates the use of the `#[instrument]` attribute macro 49 asynchronous functions. 50 + `tokio-spawny-thing.rs`: Similar to `spawny-thingy`, but with the additional 51 demonstration instrumenting [concurrent tasks][tasks] created with 52 `tokio::spawn`. 53 + `futures-proxy-server`: Demonstrates the use of `tracing-futures` by 54 implementing a simple proxy server, based on [this example][tokio-proxy] 55 from `tokio`. 56 + `async_fn`: Demonstrates how asynchronous functions can be 57 instrumented. 58 + `echo`: Demonstrates a `tracing`-instrumented variant of Tokio's `echo` example. 59- **tracing-flame**: 60 + `infero-flame`: Demonstrates the use of `tracing-flame` to generate a flamegraph 61 from spans. 62- **tracing-tower**: 63 + `tower-client`: Demonstrates the use of `tracing-tower` to instrument a 64 simple `tower` HTTP/1.1 client. 65 + `tower-server`: Demonstrates the use of `tracing-tower` to instrument a 66 simple `tower` HTTP/1.1 server. 67- **tracing-serde**: 68 + `serde-yak-shave`: Demonstrates the use of `tracing-serde` by implementing a 69 subscriber that emits trace output as JSON. 70- **tracing-log**: 71 + `hyper-echo`: Demonstrates how `tracing-log` can be used to record 72 unstructured logs from dependencies as `tracing` events, by instrumenting 73 [this example][echo] from `hyper`, and using `tracing-log` to record logs 74 emitted by `hyper`. 75- **tracing-opentelemetry**: 76 + `opentelemetry`: Demonstrates how `tracing-opentelemetry` can be used to 77 export and visualize `tracing` span data. 78 + `opentelemetry-remote-context`: Demonstrates how `tracing-opentelemetry` 79 can be used to extract and inject remote context when traces span multiple 80 systems. 81 82[tasks]: (https://docs.rs/tokio/0.2.21/tokio/task/index.html) 83[tokio-proxy]: https://github.com/tokio-rs/tokio/blob/v0.1.x/tokio/examples/proxy.rs 84[echo]: https://github.com/hyperium/hyper/blob/0.12.x/examples/echo.rs 85[`fmt`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/index.html 86[`format::Full`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/format/struct.Full.html 87[`format::Pretty`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/format/struct.Pretty.html 88[`format::Compact`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/format/struct.Compact.html 89[`format::Json`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/format/struct.Json.html 90[`fmt::Layer`]: https://docs.rs/tracing-subscriber/latest/tracing_subscriber/fmt/struct.Layer.html