Adapt logger for kuma integration

src/interfaces.ts

@@ -36,12 +36,19 @@ export interface HardenedHttpsAgentOptions extends AgentOptions {
    * @default false
    */
   enableLogging?: boolean;
+
+  /**
+   * An optional function to receive structured log objects.
+   *
+   * @default console
+   */
+  logAdapter?: LogAdapter;
 }
 
 // A minimal subset of options required for validation behavior only
 export type HardenedHttpsValidationKitOptions = Pick<
   HardenedHttpsAgentOptions,
-  'ctPolicy' | 'ocspPolicy' | 'crlSetPolicy' | 'enableLogging'
+  'ctPolicy' | 'ocspPolicy' | 'crlSetPolicy' | 'enableLogging' | 'logAdapter'
 >;
 
 export interface CertificateTransparencyPolicy {
@@ -107,4 +114,20 @@ export interface CRLSetPolicy {
    * Used only when `crlSet` is not provided.
    */
   updateStrategy?: 'always' | 'on-expiry';
-}
+}
+
+export enum LogLevel {
+  debug,
+  info,
+  warn,
+  error,
+}
+
+export interface LogObject {
+  level: LogLevel;
+  name: string;
+  message: string;
+  args?: unknown[];
+}
+
+export type LogAdapter = (log: LogObject) => void;

src/logger.ts

@@ -1,27 +1,48 @@
-/* istanbul ignore next */
+/* istanbul ignore file */
+
+import { LogLevel } from './interfaces';
+import type { LogAdapter, LogObject } from './interfaces';
+
 export class Logger {
-  private name: string;
-  private sink: LogSink;
-  constructor(name: string, sink?: LogSink) {
+  private readonly name: string;
+  private readonly adapter: LogAdapter;
+
+  constructor(name: string, adapter?: LogAdapter) {
     this.name = name;
-    this.sink = sink ?? console;
+    this.adapter =
+      adapter ??
+      (({ level, message, args }) => {
+        const timestamp = new Date().toISOString();
+        const levelString = LogLevel[level].toUpperCase();
+        console[LogLevel[level]]?.(
+          `[${timestamp}] [${this.name}] [${levelString}] ${message}`,
+          ...(args ?? [])
+        );
+      });
   }
 
-  public log(message: string, ...args: any[]): void {
-    this.sink.log(`[Log] ${this.name}: ${message}`, ...args);
+  private log(level: LogLevel, message: string, ...args: unknown[]): void {
+    this.adapter({
+      level,
+      message,
+      args,
+      name: this.name,
+    });
   }
 
-  public warn(message: string, ...args: any[]): void {
-    this.sink.warn(`[Warning] ${this.name}: ${message}`, ...args);
+  public info(message: string, ...args: unknown[]): void {
+    this.log(LogLevel.info, message, ...args);
   }
 
-  public error(message: string, ...args: any[]): void {
-    this.sink.error(`[Error] ${this.name}: ${message}`, ...args);
+  public warn(message: string, ...args: unknown[]): void {
+    this.log(LogLevel.warn, message, ...args);
   }
-}
 
-export interface LogSink {
-  log(message: string, ...args: any[]): void;
-  warn(message: string, ...args: any[]): void;
-  error(message: string, ...args: any[]): void;
+  public error(message: string, ...args: unknown[]): void {
+    this.log(LogLevel.error, message, ...args);
+  }
+
+  public debug(message: string, ...args: unknown[]): void {
+    this.log(LogLevel.debug, message, ...args);
+  }
 }

src/validation-kit.ts

@@ -1,7 +1,7 @@
 import tls from 'node:tls';
 import https from 'node:https';
 import http from 'node:http';
-import { Logger, LogSink } from './logger';
+import { Logger } from './logger';
 import type { HardenedHttpsValidationKitOptions } from './interfaces';
 import { BaseValidator } from './validators/base';
 import {
@@ -19,9 +19,11 @@ export class HardenedHttpsValidationKit {
   private readonly validators: BaseValidator[];
   private readonly validatedSockets: WeakSet<tls.TLSSocket> = new WeakSet();
 
-  constructor(options: HardenedHttpsValidationKitOptions, sink?: LogSink) {
+  constructor(options: HardenedHttpsValidationKitOptions) {
     this.options = options;
-    if (options.enableLogging) this.logger = new Logger(this.constructor.name, sink);
+    if (options.enableLogging) {
+      this.logger = new Logger(this.constructor.name, options.logAdapter);
+    }
 
     this.validators = [
       new CTValidator(this.logger),
@@ -58,7 +60,7 @@ export class HardenedHttpsValidationKit {
     try {
       // TODO: Check if best to pause the socket right after `secureConnect` event
       tlsSocket.pause();
-      this.logger?.log('Socket read paused');
+      this.logger?.debug('Socket read paused');
       shouldResume = true;
     } catch (err) {
       /* istanbul ignore next */
@@ -67,11 +69,11 @@ export class HardenedHttpsValidationKit {
 
     Promise.all(active.map((v) => v.validate(tlsSocket, this.options)))
       .then(() => {
-        this.logger?.log('All enabled validators passed.');
+        this.logger?.info('All enabled validators passed.');
         if (shouldResume) {
           try {
             tlsSocket.resume();
-            this.logger?.log('Socket read resumed');
+            this.logger?.debug('Socket read resumed');
           } catch (err) {
             /* istanbul ignore next */
             this.logger?.warn('Failed to resume socket', err);