Files
apps.apple.com/shared/logger/src/composite.ts
2025-11-04 05:03:50 +08:00

93 lines
2.8 KiB
TypeScript

import type { LoggerFactory, Logger } from './types';
export class CompositeLoggerFactory implements LoggerFactory {
private readonly factories: LoggerFactory[];
constructor(factories: LoggerFactory[]) {
this.factories = factories;
}
loggerFor(name: string): Logger {
return new CompositeLogger(
this.factories.map((factory) => factory.loggerFor(name)),
);
}
}
export class CompositeLogger implements Logger {
private readonly loggers: Logger[];
constructor(loggers: Logger[]) {
this.loggers = loggers;
}
/**
* Log a debug level message.
* Appropriate for verbose logging that explains steps/details of the inner state of
* a code unit.
*
* Example uses include in a size-constrain datastructure, logging when the size
* exceeds the threshold and elements are removed, or in a virtual scrolling
* component logging when a scroll event causes a new page of elements to be loaded.
*
* @param args Arguments to log (same as console.debug)
* @return empty string (for use in brackets {} in svelte components)
*/
debug(...args: unknown[]): string {
return this.callAll('debug', args);
}
/**
* Log an info level message.
* Appropriate for informational messages that may be relevant to consumers of a code
* unit.
*
* Example uses include a router logging when transitions occur or a button logging
* clicks.
*
* @param args Arguments to log (same as console.info)
* @return empty string (for use in brackets {} in svelte components)
*/
info(...args: unknown[]): string {
return this.callAll('info', args);
}
/**
* Log a warn level message.
* Appropriate for situations where state has been (or likely will be) corrupted or
* invariants have been broken.
*
* Example uses include a data structure warning when it is used before being fully
* initialized.
*
* @param args Arguments to log (same as console.warn)
* @return empty string (for use in brackets {} in svelte components)
*/
warn(...args: unknown[]): string {
return this.callAll('warn', args);
}
/**
* Log an error message.
* Appropriate for thrown errors or situations where the apps breaks or has to
* engage in fallback behavior to avoid a more catastrophic failure.
*
* @param args Arguments to log (same as console.error)
* @return empty string (for use in brackets {} in svelte components)
*/
error(...args: unknown[]): string {
return this.callAll('error', args);
}
private callAll(
method: 'debug' | 'info' | 'warn' | 'error',
args: unknown[],
): string {
for (const logger of this.loggers) {
logger[method](...args);
}
return '';
}
}