#logging-tracing #tracing #logging #json #tracing-subscriber #json-format #structured

tracing_sprout

A tokio-rs/tracing structured JSON formatting layer for the fledgling logger

6 releases

0.1.0-alpha.6 Jul 10, 2022
0.1.0-alpha.5 Jul 9, 2022
0.1.0-alpha.4 Jul 6, 2022
0.1.0-alpha.3 Jul 2, 2022
0.1.0-alpha.1 Feb 13, 2021

#729 in Debugging

26 downloads per month

MIT license

26KB
333 lines

Tracing Sprout

A tokio-rs/tracing structured JSON formatting layer for the fledgling logger

crates.io docs repo MIT

Heavily inspired by Tracing Bunyan Formatter, just with some slight tweaks to the internals and the formatting. The actual formatting doesn't follow any defined specification, it's just something I view as readable and useful - I'm open to suggestions if people would like it aligned to a specific format.

Features

  • All traces will receive their parent's attributes as well as their own, child attributes will take precedence if there are collisions
  • There is a very minimal timing capability that adds elapsed time to EVENT and EXIT traces
  • TRACE, DEBUG and ERROR logs get slightly more metadata (file name, line number, module path & target) attached to them
  • Avoids panics - as much as possible it opts to handle failure by eprintlning to stdout. These scenarios should be few and far between, but it's better that a failure in your tracing implementation doesn't poison your main application. (although ideally it shouldn't fail silently)

All traces will receive their parent's attributes as well as their own, there is also a very minimal timing capability that adds elapsed time to Event and Exit traces

Basic Example

See /examples for a slightly more complex example

use tracing::{subscriber::set_global_default, Subscriber};
use tracing_sprout::TrunkLayer;
use tracing_subscriber::prelude::*;
use tracing_subscriber::{EnvFilter, Registry};

let env_filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info"));
let formatting_layer = TrunkLayer::new("My Application".to_string(), env!("CARGO_PKG_VERSION").to_string(), std::io::stdout);
let subscriber = Registry::default()
     .with(env_filter)
     .with(formatting_layer);

set_global_default(subscriber).expect("failed to set up global tracing subscriber")

Example Output

Raw JSON

{"name":"I'm Groot","version":"0.1.0-alpha.1","id":"1","time":"Sat, 02 Jul 2022 09:33:59 -0600","msg":"[EPIC MONTAGE | START]","level":"info","span_type":"enter"}
{"name":"I'm Groot","version":"0.1.0-alpha.1","id":"1","group":["Peter Quill","Gamora","Drax","Rocket"],"time":"Sat, 02 Jul 2022 09:33:59 -0600","msg":"[EVENT] Trying to plug in the power","level":"trace","file":"examples/basic.rs","line":32,"target":"basic","thread_id":"ThreadId(1)","thread_name":"main","span_type":"event"}
{"name":"I'm Groot","version":"0.1.0-alpha.1","id":"2","info":"I'm overwriting my parents ID","time":"Sat, 02 Jul 2022 09:33:59 -0600","msg":"[MUSIC IS PLAYING | START]","level":"debug","file":"examples/basic.rs","line":34,"target":"basic","thread_id":"ThreadId(1)","thread_name":"main","span_type":"enter"}

Piped through CLI tool

In this case the CLI tool used was pino-pretty

[Sat, 02 Jul 2022 09:34:55 -0600] INFO (I'm Groot): [EPIC MONTAGE | STA
    version: "0.1.0-alpha.1"
    id: "1"
    span_type: "enter"
[Sat, 02 Jul 2022 09:34:55 -0600] TRACE (I'm Groot): [EVENT] Trying to
    version: "0.1.0-alpha.1"
    id: "1"
    group: [
      "Peter Quill",
      "Gamora",
      "Drax",
      "Rocket"
    ]
    file: "examples/basic.rs"
    line: 32
    target: "basic"
    thread_id: "ThreadId(1)"
    thread_name: "main"
    span_type: "event"
[Sat, 02 Jul 2022 09:34:55 -0600] DEBUG (I'm Groot): [MUSIC IS PLAYING | START]
    version: "0.1.0-alpha.1"
    id: "2"
    info: "I'm overwriting my parents ID"
    file: "examples/basic.rs"
    line: 34
    target: "basic"
    thread_id: "ThreadId(1)"
    thread_name: "main"
    span_type: "enter"
[Sat, 02 Jul 2022 09:34:55 -0600] INFO (I'm Groot): [DANCE | START]
    version: "0.1.0-alpha.1"
    id: "2"
    info: "I'm overwriting my parents ID"
    span_type: "enter"

Dependencies

~2.8–4MB
~65K SLoC