Struct JsonFormatter

pub struct JsonFormatter(/* private fields */);

Available on crate feature serde_json only.

JSON logs formatter.

Each log will be serialized into a single line of JSON object with the following schema.

Schema

Field	Type	Description
level	String	The level of the log. Same as the return of Level::as_str.
timestamp	Integer(u64)	The timestamp when the log was generated, in milliseconds since January 1, 1970 00:00:00 UTC.
payload	String	The contents of the log.
logger	String/Null	The name of the logger. Null if the logger has no name.
tid	Integer(u64)	The thread ID when the log was generated.
source	Object/Null	The source location of the log. See SourceLocation for its schema. Null if crate feature source-location is not enabled.

• If the type of a field is Null, the field will not be present or be null.

• The order of the fields is not guaranteed.

---

Examples

• Default:

  {"level":"info","timestamp":1722817424798,"payload":"hello, world!","tid":3472525}
  {"level":"error","timestamp":1722817424798,"payload":"something went wrong","tid":3472525}

• If the logger has a name:

  {"level":"info","timestamp":1722817541459,"payload":"hello, world!","logger":"app-component","tid":3478045}
  {"level":"error","timestamp":1722817541459,"payload":"something went wrong","logger":"app-component","tid":3478045}

• If crate feature source-location is enabled:

  {"level":"info","timestamp":1722817572709,"payload":"hello, world!","tid":3479856,"source":{"module_path":"my_app::say_hi","file":"src/say_hi.rs","line":4,"column":5}}
  {"level":"error","timestamp":1722817572709,"payload":"something went wrong","tid":3479856,"source":{"module_path":"my_app::say_hi","file":"src/say_hi.rs","line":5,"column":5}}

Implementations

impl JsonFormatter

pub fn new() -> JsonFormatter

Constructs a JsonFormatter.

Trait Implementations

impl Clone for JsonFormatter

fn clone(&self) -> JsonFormatter

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Default for JsonFormatter

fn default() -> Self

Returns the “default value” for a type.

impl Formatter for JsonFormatter

fn format( &self, record: &Record<'_>, dest: &mut StringBuf, ctx: &mut FormatterContext<'_>, ) -> Result<()>

Formats a log record.