ecs-logger

A Rust logger compatible with Elastic Common Schema (ECS) Logging.

Features

• Configurable via the RUST_LOG environment variable.
  • Uses env_logger under the hood.
  • All logging is disabled except for the error level by default.
• Logs are written to stderr by default.

Installation

Add the following to your Cargo.toml file:

[dependencies]
log = "0.4"
ecs-logger = "1"

Documentation

Available at docs.rs

Example

In the following examples we assume the binary is ./example.

Basic logging

use log::{debug, error};

ecs_logger::init();

debug!(
    "this is a debug {}, which is NOT printed by default",
    "message"
);
error!("this is printed by default");

$ ./example
{"@timestamp":"2021-11-26T15:25:22.321002600Z","log.level":"ERROR","message":"this is printed by default","ecs.version":"1.12.1","log.origin":{"file":{"line":13,"name":"example.rs"},"rust":{"target":"example::tests","module_path":"example::tests","file_path":"tests/example.rs"}}}

$ RUST_LOG=debug ./example
{"@timestamp":"2021-11-26T15:26:13.524069Z","log.level":"DEBUG","message":"this is a debug message, which is NOT printed by default","ecs.version":"1.12.1","log.origin":{"file":{"line":9,"name":"example.rs"},"rust":{"target":"example::tests","module_path":"example::tests","file_path":"tests/example.rs"}}}
{"@timestamp":"2021-11-26T15:26:13.524193100Z","log.level":"ERROR","message":"this is printed by default","ecs.version":"1.12.1","log.origin":{"file":{"line":13,"name":"example.rs"},"rust":{"target":"example::tests","module_path":"example::tests","file_path":"tests/example.rs"}}}

More filtering config examples are available at env_logger’s documentation.

Extra Fields

You can add extra fields to the log output by using the extra_fields module.

use ecs_logger::extra_fields;
use serde::Serialize;

#[derive(Serialize)]
struct MyExtraFields {
  my_field: String,
}

ecs_logger::init();

extra_fields::set_extra_fields(MyExtraFields {
  my_field: "my_value".to_string(),
}).unwrap();

log::error!("Hello {}!", "world");
log::info!("Goodbye {}!", "world");

extra_fields::clear_extra_fields();

Custom logging

You need to add env_logger to your Cargo.toml for the following examples.

[dependencies]
log = "0.4"
env_logger = "0.9"
ecs-logger = "1"

Write to stdout

use log::info;

// Initialize custom logger
env_logger::builder()
    .format(ecs_logger::format) // Configure ECS logger
    .target(env_logger::Target::Stdout) // Write to stdout
    .init();

info!("Hello {}!", "world");

Configure log filters

use log::info;

// Initialize custom logger
env_logger::builder()
    .parse_filters("info,my_app=debug") // Set filters
    .format(ecs_logger::format) // Configure ECS logger
    .init();

info!("Hello {}!", "world");

Default log fields

{
    "@timestamp": "2021-11-26T15:25:22.321002600Z",
    "log.level": "ERROR",
    "message": "this is printed by default",
    "ecs.version": "1.12.1",
    "log.origin": {
        "file": {
            "line": 13,
            "name": "example.rs"
        },
        "rust": {
            "target": "example::tests",
            "module_path": "example::tests",
            "file_path": "tests/example.rs"
        }
    }
}

License

Licensed under either of

• Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Acknowledgment

The implementation of this software is based on env_logger, which is dual licenced as well.