Struct Logger 

pub struct Logger { /* private fields */ }

Writes log lines with a set of fields; cheap to clone (see the module documentation).

Ctx::log gives the request’s logger; code without a Ctx uses Logger::new.

Examples

use ocre::log::{Format, Level, Logger};

let log = Logger::new().with("order_id", 42).with("password", "hunter2");
log.info("paid"); // written to the Worker logs
assert_eq!(
    log.line(Level::Info, "paid", Format::Json),
    r#"{"level":"info","message":"paid","order_id":42,"password":"[FILTERED]"}"#
);
assert_eq!(log.line(Level::Warn, "slow", Format::Text), "WARN slow order_id=42 password=[FILTERED]");

Implementations

impl Logger

pub fn new() -> Self

A logger without fields.

Examples

ocre::log::Logger::new().warn("cache miss");

pub fn with(&self, key: &str, value: impl Serialize) -> Self

A copy of this logger with one more field on every line (Rails’ logger.tagged).

Any serializable value; a value that does not serialize is written as null. A field with the same name is replaced.

Examples

let log = ocre::log::Logger::new().with("user_id", 7);
assert_eq!(log.field("user_id"), Some(&serde_json::json!(7)));

pub fn field(&self, key: &str) -> Option<&Value>

The value of a field, e.g. request_id.

Examples

assert_eq!(ocre::log::Logger::new().field("request_id"), None);

pub fn enabled(&self, level: Level) -> bool

Whether lines of level are written, under the current LOG_LEVEL.

Check it before building an expensive message that is not format_args!(...) (Rails’ block form of logger.debug { ... }).

Examples

let log = ocre::log::Logger::new();
if log.enabled(ocre::log::Level::Debug) {
    log.debug(serde_json::json!({"big": [1, 2, 3]}));
}

pub fn debug(&self, message: impl Display)

Writes a debug line.

Examples

let rows = 3;
ocre::log::Logger::new().debug(format_args!("{rows} rows"));

pub fn info(&self, message: impl Display)

Writes an info line.

Examples

ocre::log::Logger::new().info("signed up");

pub fn warn(&self, message: impl Display)

Writes a warn line.

Examples

ocre::log::Logger::new().warn("retrying");

pub fn error(&self, message: impl Display)

Writes an error line.

Examples

ocre::log::Logger::new().error("payment provider down");

pub fn log(&self, level: Level, message: &dyn Display)

Writes a line of level when it is enabled; the message is formatted only then.

Examples

ocre::log::Logger::new().log(ocre::log::Level::Info, &"hello");

pub fn line(&self, level: Level, message: &str, format: Format) -> String

The line log writes, whatever the current level: JSON or text.

Examples

use ocre::log::{Format, Level, Logger};

let line = Logger::new().with("path", "/a b").line(Level::Error, "boom", Format::Text);
assert_eq!(line, r#"ERROR boom path="/a b""#);

Trait Implementations

impl Clone for Logger

fn clone(&self) -> Logger

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for Logger

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for Logger

fn default() -> Logger

Returns the “default value” for a type.