feat(node): pluggable logging class (support different strategies)

Author: AndriiAndreiev

packages/node/src/lib/console-logger.ts

@@ -0,0 +1,55 @@
+import type { Log, ErrorLog, LoggerStrategy } from './logger';
+
+/**
+ * Implementation of the console logger strategy.
+ */
+export default class ConsoleLogger implements LoggerStrategy {
+  /**
+   * This method takes a level of the log and a message and formats it to the unified log format
+   * @returns A formatted log message
+   */
+  // eslint-disable-next-line class-methods-use-this
+  private formatMessage(level: 'DEBUG' | 'ERROR' | 'TRACE', message: string): string[] {
+    return [`${level} ${new Date().toISOString()} [readmeio] ${message}`];
+  }
+
+  /**
+   * Logs a trace message to the console.
+   * @param log The trace log entry. Contains the message as required field and optional args.
+   */
+  trace({ message, args }: Log): void {
+    const params: unknown[] = this.formatMessage('TRACE', message);
+    console.trace(...params);
+    if (args) {
+      console.dir(args, { depth: null });
+      console.log('\n');
+    }
+  }
+
+  /**
+   * Logs a debug message to the console.
+   * @param log The debug log entry. Contains the message as required field and optional args.
+   */
+  debug({ message, args }: Log): void {
+    const params: unknown[] = this.formatMessage('DEBUG', message);
+    if (args) {
+      params.push('\nArguments:', args);
+    }
+    console.debug(...params, '\n');
+  }
+
+  /**
+   * Logs an error message to the console.
+   * @param log The error log entry. Contains the message and error object as required fields and optional args.
+   */
+  error({ message, args, err }: ErrorLog): void {
+    const params: unknown[] = this.formatMessage('ERROR', message);
+    if (args) {
+      params.push('\nArguments:', args);
+    }
+    if (err) {
+      params.push('\n', err);
+    }
+    console.error(...params, '\n');
+  }
+}

packages/node/src/lib/construct-payload.ts

@@ -1,3 +1,4 @@
+import type { LoggerStrategy } from './logger';
 import type { OutgoingLogBody } from './metrics-log';
 import type { UUID } from 'node:crypto';
 import type { IncomingMessage, ServerResponse } from 'node:http';
@@ -55,9 +56,9 @@ export interface LogOptions {
   fireAndForget?: boolean;
 
   /**
-   * If true, the errors and other logs will be displayed in console.
+   * If true, the errors and other logs will be displayed in console. Your own logger strategy can be passed.
    */
-  logger?: boolean;
+  logger?: LoggerStrategy | boolean;
 
   /**
    * @deprecated use `allowList` instead

packages/node/src/lib/log.ts

@@ -107,7 +107,10 @@ export function log(
 ) {
   if (!readmeApiKey) throw new Error('You must provide your ReadMe API key');
   if (!group) throw new Error('You must provide a group');
-  if (options.logger) logger.configure({ isLoggingEnabled: true });
+  if (options.logger) {
+    if (typeof options.logger === 'boolean') logger.configure({ isLoggingEnabled: true });
+    else logger.configure({ isLoggingEnabled: true, strategy: options.logger });
+  }
 
   // Ensures the buffer length is between 1 and 30
   const bufferLength = clamp(options.bufferLength || config.bufferLength, 1, 30);

packages/node/src/lib/logger.ts

@@ -1,24 +1,29 @@
+import ConsoleLogger from './console-logger';
+
 interface LoggerConfig {
   isLoggingEnabled: boolean;
-  logPrefix: string;
+  strategy: LoggerStrategy;
 }
 
-interface Log {
+export interface Log {
   args?: Record<string, unknown>;
   message: string;
 }
 
-type ErrorLog = Log & { err?: Error };
+export type ErrorLog = Log & { err?: Error };
 
-export interface Logger {
-  configure(config: Partial<LoggerConfig>): void;
+export interface LoggerStrategy {
   debug(log: Log): void;
   error(log: ErrorLog): void;
   trace(log: Log): void;
 }
 
+export interface Logger extends LoggerStrategy {
+  configure(config: Partial<LoggerConfig>): void;
+}
+
 /**
- * Default implementation of the Logger interface. Represents a signleton class of console logger.
+ * Default implementation of the Logger interface. Represents a signleton class of logger with selected strategy.
  */
 class DefaultLogger implements Logger {
   private static instance: Logger;
@@ -37,7 +42,7 @@ class DefaultLogger implements Logger {
     if (!DefaultLogger.instance) {
       const defaultConfig: LoggerConfig = {
         isLoggingEnabled: false,
-        logPrefix: '[readmeio]',
+        strategy: new ConsoleLogger(),
       };
       DefaultLogger.instance = new DefaultLogger(defaultConfig);
     }
@@ -53,55 +58,30 @@ class DefaultLogger implements Logger {
   }
 
   /**
-   * This method takes a level of the log and a message and formats it to the unified log format
-   * @returns A formatted log message
-   */
-
-  private formatMessage(level: 'DEBUG' | 'ERROR' | 'TRACE', message: string): string[] {
-    return [`${level} ${new Date().toISOString()} ${this.config.logPrefix} ${message}`];
-  }
-
-  /**
-   * Logs a trace message.
-   * @param log The trace log entry. Contains the message as required field and optional args.
+   * Logs an error message.
+   * @param log The error log entry. Contains the message and error object as required fields and optional args.
    */
-  trace({ message, args }: Log): void {
+  error(log: ErrorLog): void {
     if (!this.config.isLoggingEnabled) return;
-    const params: unknown[] = this.formatMessage('TRACE', message);
-    console.log(...params);
-    if (args) {
-      console.dir(args, { depth: null });
-      console.log('\n');
-    }
+    this.config.strategy.error(log);
   }
 
   /**
    * Logs a debug message.
    * @param log The debug log entry. Contains the message as required field and optional args.
    */
-  debug({ message, args }: Log): void {
+  debug(log: Log): void {
     if (!this.config.isLoggingEnabled) return;
-    const params: unknown[] = this.formatMessage('DEBUG', message);
-    if (args) {
-      params.push('\nArguments:', args);
-    }
-    console.debug(...params, '\n');
+    this.config.strategy.debug(log);
   }
 
   /**
-   * Logs an error message.
-   * @param log The error log entry. Contains the message and error object as required fields and optional args.
+   * Logs a trace message.
+   * @param log The trace log entry. Contains the message as required field and optional args.
    */
-  error({ message, args, err }: ErrorLog): void {
+  trace(log: Log): void {
     if (!this.config.isLoggingEnabled) return;
-    const params: unknown[] = this.formatMessage('ERROR', message);
-    if (args) {
-      params.push('\nArguments:', args);
-    }
-    if (err) {
-      params.push('\n', err);
-    }
-    console.error(...params, '\n');
+    this.config.strategy.trace(log);
   }
 }