Logging service
Allows a plugin to provide status and diagnostic information.
Note
The Logging service is only available server side.
For editorial guidance on what to log and what to avoid (sensitive data, noisy info messages, implementation details), see the logging guidelines.
import type { PluginInitializerContext, CoreSetup, Plugin, Logger } from '@kbn/core/server';
export class MyPlugin implements Plugin {
private readonly logger: Logger;
constructor(initializerContext: PluginInitializerContext) {
this.logger = initializerContext.logger.get();
}
public setup(core: CoreSetup) {
try {
this.logger.debug('doing something...');
// …
} catch (e) {
this.logger.error('failed doing something...');
}
}
}
Usage is very straightforward, one should just get a logger for a specific context and use it to log messages with different log level.
const logger = kibana.logger.get('server');
logger.trace('Message with `trace` log level.');
logger.debug('Message with `debug` log level.');
logger.info('Message with `info` log level.');
logger.warn('Message with `warn` log level.');
logger.error('Message with `error` log level.');
logger.fatal('Message with `fatal` log level.');
const loggerWithNestedContext = kibana.logger.get('server', 'http');
loggerWithNestedContext.trace('Message with `trace` log level.');
loggerWithNestedContext.debug('Message with `debug` log level.');
And assuming logger for server name with console appender and trace level was used, console output will look like this:
[2017-07-25T11:54:41.639-07:00][TRACE][server] Message with `trace` log level.
[2017-07-25T11:54:41.639-07:00][DEBUG][server] Message with `debug` log level.
[2017-07-25T11:54:41.639-07:00][INFO ][server] Message with `info` log level.
[2017-07-25T11:54:41.639-07:00][WARN ][server] Message with `warn` log level.
[2017-07-25T11:54:41.639-07:00][ERROR][server] Message with `error` log level.
[2017-07-25T11:54:41.639-07:00][FATAL][server] Message with `fatal` log level.
[2017-07-25T11:54:41.639-07:00][TRACE][server.http] Message with `trace` log level.
[2017-07-25T11:54:41.639-07:00][DEBUG][server.http] Message with `debug` log level.
The log will be less verbose with warn level for the server logger:
[2017-07-25T11:54:41.639-07:00][WARN ][server] Message with `warn` log level.
[2017-07-25T11:54:41.639-07:00][ERROR][server] Message with `error` log level.
[2017-07-25T11:54:41.639-07:00][FATAL][server] Message with `fatal` log level.