Add bun.lock for dependency management, update package version to 2025.1.0, refine TypeScript dependencies, and introduce tsconfig.build.json for type declaration output. Enhance RtmpPush class with dependency injection for command building and process management, and implement new interfaces for better extensibility.

bun.lock

@@ -0,0 +1,39 @@
+{
+  "lockfileVersion": 1,
+  "configVersion": 0,
+  "workspaces": {
+    "": {
+      "name": "@techniker-me/rtmp-push",
+      "devDependencies": {
+        "@types/bun": "latest",
+        "@types/node": "^25.0.3",
+        "prettier": "^3.7.4",
+        "typescript": "^5.9.3",
+      },
+      "peerDependencies": {
+        "typescript": "^5.9.3",
+      },
+    },
+  },
+  "packages": {
+    "@types/bun": ["@types/bun@1.2.20", "https://registry-node.techniker.me/@types/bun/-/bun-1.2.20.tgz", { "dependencies": { "bun-types": "1.2.20" } }, "sha512-dX3RGzQ8+KgmMw7CsW4xT5ITBSCrSbfHc36SNT31EOUg/LA9JWq0VDdEXDRSe1InVWpd2yLUM1FUF/kEOyTzYA=="],
+
+    "@types/node": ["@types/node@25.0.3", "", { "dependencies": { "undici-types": "~7.16.0" } }, "sha512-W609buLVRVmeW693xKfzHeIV6nJGGz98uCPfeXI1ELMLXVeKYZ9m15fAMSaUPBHYLGFsVRcMmSCksQOrZV9BYA=="],
+
+    "@types/react": ["@types/react@19.1.10", "", { "dependencies": { "csstype": "^3.0.2" } }, ""],
+
+    "bun-types": ["bun-types@1.2.20", "", { "dependencies": { "@types/node": "*" }, "peerDependencies": { "@types/react": "^19" } }, ""],
+
+    "csstype": ["csstype@3.1.3", "", {}, ""],
+
+    "prettier": ["prettier@3.7.4", "", { "bin": { "prettier": "bin/prettier.cjs" } }, "sha512-v6UNi1+3hSlVvv8fSaoUbggEM5VErKmmpGA7Pl3HF8V6uKY7rvClBOJlH6yNwQtfTueNkGVpOv/mtWL9L4bgRA=="],
+
+    "typescript": ["typescript@5.9.3", "", { "bin": { "tsc": "bin/tsc", "tsserver": "bin/tsserver" } }, "sha512-jl1vZzPDinLr9eUt3J/t7V6FgNEw9QjvBPdysz9KfQDD41fQrC2Y4vKQdiaUpFT4bXlb1RHhLpp8wtm6M5TgSw=="],
+
+    "undici-types": ["undici-types@7.16.0", "", {}, "sha512-Zz+aZWSj8LE6zoxD+xrjh4VfkIG8Ya6LvYkZqtUQGJPZjYl53ypCaUwWqo7eI0x66KBGeRo+mlBEkMSeSZ38Nw=="],
+
+    "bun-types/@types/node": ["@types/node@20.19.11", "https://registry-node.techniker.me/@types/node/-/node-20.19.11.tgz", { "dependencies": { "undici-types": "~6.21.0" } }, "sha512-uug3FEEGv0r+jrecvUUpbY8lLisvIjg6AAic6a2bSP5OEOLeJsDSnvhCDov7ipFFMXS3orMpzlmi0ZcuGkBbow=="],
+
+    "bun-types/@types/node/undici-types": ["undici-types@6.21.0", "https://registry-node.techniker.me/undici-types/-/undici-types-6.21.0.tgz", {}, "sha512-iwDZqg0QAGrg9Rav5H4n0M64c3mkR59cJ6wQp+7C4nI0gsmExaedaYLNO44eT4AtBBwjbTiGPMlt2Md0T9H9JQ=="],
+  }
+}

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@techniker-me/rtmp-push",
-  "version": "2025.0.3",
+  "version": "2025.1.0",
   "description": "A TypeScript library for pushing media streams to RTMP servers using FFmpeg",
   "main": "dist/node/index.js",
   "module": "src/index.ts",
@@ -14,18 +14,18 @@
     "ci-build": "bun run build:node && bun run build:browser && bun run build:types",
     "build:node": "bun build src/index.ts --outdir dist/node --target node --format esm --minify --production",
     "build:browser": "bun build src/index.ts --outdir dist/browser --target browser --format esm --minify --production",
-    "build:types": "tsc --outDir dist/types",
+    "build:types": "tsc --project tsconfig.build.json",
     "prepublishOnly": "bun run build",
     "clean": "rm -rf dist"
   },
   "devDependencies": {
     "@types/bun": "latest",
-    "@types/node": "20.0.0",
-    "prettier": "3.6.2",
-    "typescript": "5.9.2"
+    "@types/node": "^25.0.3",
+    "prettier": "^3.7.4",
+    "typescript": "^5.9.3"
   },
   "peerDependencies": {
-    "typescript": "5.9.2"
+    "typescript": "^5.9.3"
   },
   "exports": {
     ".": {

src/RtmpPush.ts

@@ -1,13 +1,49 @@
-import {spawn, ChildProcess} from 'node:child_process';
+import type {ICommandBuilder} from './interfaces/ICommandBuilder.js';
+import type {IProcessManager} from './interfaces/IProcessManager.js';
+import {CommandBuilder} from './implementations/CommandBuilder.js';
+import {ProcessManager} from './implementations/ProcessManager.js';
+import {ProcessSpawner} from './implementations/ProcessSpawner.js';
+import {ConsoleLogger} from './implementations/ConsoleLogger.js';
 
+/**
+ * Configuration options for RtmpPush
+ */
+export interface RtmpPushOptions {
+  commandBuilder?: ICommandBuilder;
+  processManager?: IProcessManager;
+  ffmpegCommand?: string;
+}
+
+/**
+ * RTMP Push class for streaming media to RTMP servers
+ * 
+ * Follows SOLID principles:
+ * - Single Responsibility: Orchestrates RTMP streaming workflow
+ * - Open/Closed: Extensible via dependency injection
+ * - Liskov Substitution: Works with any ICommandBuilder/IProcessManager implementation
+ * - Interface Segregation: Uses focused interfaces
+ * - Dependency Inversion: Depends on abstractions, not concretions
+ */
 export class RtmpPush {
-  private _mediaSourceUri: string;
-  private _rtmpIngestUri: string;
-  private _activeProcess: ChildProcess | null = null;
+  private readonly commandBuilder: ICommandBuilder;
+  private readonly processManager: IProcessManager;
+  private readonly _mediaSourceUri: string;
+  private readonly _rtmpIngestUri: string;
 
-  constructor(mediaSourceUri: string, rtmpIngestUri: string) {
+  constructor(
+    mediaSourceUri: string,
+    rtmpIngestUri: string,
+    options: RtmpPushOptions = {}
+  ) {
     this._mediaSourceUri = mediaSourceUri;
     this._rtmpIngestUri = rtmpIngestUri;
+    
+    // Dependency Injection with defaults (Dependency Inversion Principle)
+    this.commandBuilder = options.commandBuilder ?? new CommandBuilder(options.ffmpegCommand);
+    this.processManager = options.processManager ?? new ProcessManager(
+      new ProcessSpawner(),
+      new ConsoleLogger()
+    );
   }
 
   get rtmpIngestUri(): string {
@@ -18,80 +54,57 @@ export class RtmpPush {
     return this._mediaSourceUri;
   }
 
+  /**
+   * Start streaming to RTMP server
+   * @param streamKey - The stream key for the RTMP stream
+   * @param capabilities - Array of capability strings
+   * @returns This instance for method chaining
+   */
   public start(streamKey: string, capabilities: string[]): this {
-    // Use the constructor parameters instead of hardcoded values
-    const mediaSourceUri = this._mediaSourceUri;
-    const ingestUri = `${this._rtmpIngestUri}/${streamKey};capabilities=${capabilities.join(',')};tags=`;
-    const command = [
-      'ffmpeg',
-      '-re',
-      '-hide_banner',
-      '-stream_loop',
-      '-1',
-      '-y',
-      '-flags',
-      'low_delay',
-      '-fflags',
-      '+nobuffer+flush_packets',
-      '-i',
-      mediaSourceUri,
-      '-c:a',
-      'copy',
-      '-c:v',
-      'copy',
-      '-flush_packets',
-      '1',
-      '-copyts',
-      '-f',
-      'flv',
-      ingestUri
-    ];
-
-    try {
-      if (!command[0]) {
-        throw new Error('Invalid command: ffmpeg not found');
+    if (this.processManager.isRunning()) {
+      throw new Error('Stream is already running');
     }
 
-      this._activeProcess = spawn(command[0], command.slice(1));
+    const command = this.commandBuilder.buildCommand(
+      this._mediaSourceUri,
+      this._rtmpIngestUri,
+      streamKey,
+      capabilities
+    );
 
-      if (!this._activeProcess) {
-        throw new Error('Failed to spawn ffmpeg process');
+    const [ffmpegCommand, ...args] = command;
+
+    if (!ffmpegCommand) {
+      throw new Error('Invalid command: ffmpeg command not found');
     }
 
-      this._activeProcess.stdout?.on('data', data => {
-        console.log(`stdout: ${data}`);
-      });
-
-      this._activeProcess.stderr?.on('data', data => {
-        console.log(`stderr: ${data}`);
-      });
-
-      this._activeProcess.on('close', code => {
-        console.log(`child process exited with code ${code}`);
-        this._activeProcess = null;
-      });
-
-      this._activeProcess.on('error', error => {
-        console.error('ffmpeg process error:', error);
-        this._activeProcess = null;
-      });
-    } catch (error) {
-      console.error('Failed to start RTMP push:', error);
-      throw error;
-    }
+    this.processManager.start(ffmpegCommand, args);
 
     return this;
   }
 
+  /**
+   * Stop the current stream
+   * @returns This instance for method chaining
+   */
   public stop(): this {
-    if (this._activeProcess) {
-      this._activeProcess.kill();
-      this._activeProcess = null;
-    }
+    this.processManager.stop();
     return this;
   }
 
+  /**
+   * Check if stream is currently running
+   * @returns True if stream is active
+   */
   public isRunning(): boolean {
-    return this._activeProcess !== null && !this._activeProcess.killed;
+    return this.processManager.isRunning();
+  }
+
+  /**
+   * Get the process manager for event handling
+   * Allows access to process events (data, error, close)
+   */
+  public getProcessManager(): IProcessManager {
+    return this.processManager;
   }
 }

src/implementations/CommandBuilder.ts

@@ -0,0 +1,48 @@
+import type {ICommandBuilder} from '../interfaces/ICommandBuilder.js';
+
+/**
+ * Builds FFmpeg commands for RTMP streaming
+ * Single Responsibility: Command construction only
+ */
+export class CommandBuilder implements ICommandBuilder {
+  private readonly ffmpegCommand: string;
+
+  constructor(ffmpegCommand: string = 'ffmpeg') {
+    this.ffmpegCommand = ffmpegCommand;
+  }
+
+  buildCommand(
+    mediaSourceUri: string,
+    rtmpIngestUri: string,
+    streamKey: string,
+    capabilities: string[]
+  ): string[] {
+    const ingestUri = `${rtmpIngestUri}/${streamKey};capabilities=${capabilities.join(',')};tags=`;
+
+    return [
+      this.ffmpegCommand,
+      '-re',
+      '-hide_banner',
+      '-stream_loop',
+      '-1',
+      '-y',
+      '-flags',
+      'low_delay',
+      '-fflags',
+      '+nobuffer+flush_packets',
+      '-i',
+      mediaSourceUri,
+      '-c:a',
+      'copy',
+      '-c:v',
+      'copy',
+      '-flush_packets',
+      '1',
+      '-copyts',
+      '-f',
+      'flv',
+      ingestUri
+    ];
+  }
+}
+

src/implementations/ConsoleLogger.ts

@@ -0,0 +1,16 @@
+import type {ILogger} from '../interfaces/ILogger.js';
+
+/**
+ * Console-based logger implementation
+ * Single Responsibility: Logging only
+ */
+export class ConsoleLogger implements ILogger {
+  log(message: string): void {
+    console.log(message);
+  }
+
+  error(message: string, error?: unknown): void {
+    console.error(message, error);
+  }
+}
+

src/implementations/ProcessManager.ts

@@ -0,0 +1,85 @@
+import {ChildProcess} from 'node:child_process';
+import type {IProcessManager, ProcessManagerEvents} from '../interfaces/IProcessManager.js';
+import type {IProcessSpawner} from '../interfaces/IProcessSpawner.js';
+import type {ILogger} from '../interfaces/ILogger.js';
+import {EventEmitter} from 'node:events';
+
+/**
+ * Manages process lifecycle
+ * Single Responsibility: Process management only
+ * Open/Closed: Can be extended without modification
+ */
+export class ProcessManager extends EventEmitter implements IProcessManager {
+  private activeProcess: ChildProcess | null = null;
+
+  constructor(
+    private readonly processSpawner: IProcessSpawner,
+    private readonly logger: ILogger
+  ) {
+    super();
+  }
+
+  start(command: string, args: string[]): void {
+    if (this.isRunning()) {
+      throw new Error('Process is already running');
+    }
+
+    if (!command) {
+      throw new Error('Invalid command: command cannot be empty');
+    }
+
+    try {
+      this.activeProcess = this.processSpawner.spawn(command, args);
+
+      if (!this.activeProcess) {
+        throw new Error('Failed to spawn process');
+      }
+
+      this.setupEventHandlers();
+    } catch (error) {
+      this.logger.error('Failed to start process:', error);
+      this.activeProcess = null;
+      throw error;
+    }
+  }
+
+  stop(): void {
+    if (this.activeProcess) {
+      this.activeProcess.kill();
+      this.activeProcess = null;
+    }
+  }
+
+  isRunning(): boolean {
+    return this.activeProcess !== null && !this.activeProcess.killed;
+  }
+
+  private setupEventHandlers(): void {
+    if (!this.activeProcess) {
+      return;
+    }
+
+    this.activeProcess.stdout?.on('data', (data: Buffer) => {
+      this.logger.log(`stdout: ${data}`);
+      this.emit('data', data);
+    });
+
+    this.activeProcess.stderr?.on('data', (data: Buffer) => {
+      this.logger.log(`stderr: ${data}`);
+      this.emit('data', data);
+    });
+
+    this.activeProcess.on('close', (code: number | null) => {
+      this.logger.log(`child process exited with code ${code}`);
+      this.activeProcess = null;
+      this.emit('close', code);
+    });
+
+    this.activeProcess.on('error', (error: Error) => {
+      this.logger.error('Process error:', error);
+      this.activeProcess = null;
+      this.emit('error', error);
+    });
+  }
+}
+

src/implementations/ProcessSpawner.ts

@@ -0,0 +1,13 @@
+import {spawn, ChildProcess} from 'node:child_process';
+import type {IProcessSpawner} from '../interfaces/IProcessSpawner.js';
+
+/**
+ * Default implementation of process spawner
+ * Single Responsibility: Process spawning only
+ */
+export class ProcessSpawner implements IProcessSpawner {
+  spawn(command: string, args: string[]): ChildProcess {
+    return spawn(command, args);
+  }
+}
+

src/index.ts

@@ -1,4 +1,19 @@
-import {RtmpPush} from './RtmpPush.js';
+// Main export
+export {RtmpPush} from './RtmpPush.js';
+export type {RtmpPushOptions} from './RtmpPush.js';
 
-export {RtmpPush};
+// Interfaces (for extensibility)
+export type {ICommandBuilder} from './interfaces/ICommandBuilder.js';
+export type {IProcessManager, ProcessManagerEvents} from './interfaces/IProcessManager.js';
+export type {IProcessSpawner} from './interfaces/IProcessSpawner.js';
+export type {ILogger} from './interfaces/ILogger.js';
+
+// Default implementations (for convenience)
+export {CommandBuilder} from './implementations/CommandBuilder.js';
+export {ProcessManager} from './implementations/ProcessManager.js';
+export {ProcessSpawner} from './implementations/ProcessSpawner.js';
+export {ConsoleLogger} from './implementations/ConsoleLogger.js';
+
+// Default export
+import {RtmpPush} from './RtmpPush.js';
 export default {RtmpPush};

src/interfaces/ICommandBuilder.ts

@@ -0,0 +1,8 @@
+/**
+ * Interface for building FFmpeg commands (Interface Segregation Principle)
+ * Separates command building logic from process management
+ */
+export interface ICommandBuilder {
+  buildCommand(mediaSourceUri: string, rtmpIngestUri: string, streamKey: string, capabilities: string[]): string[];
+}
+

src/interfaces/ILogger.ts

@@ -0,0 +1,9 @@
+/**
+ * Interface for logging (Dependency Inversion Principle)
+ * Allows for different logging implementations
+ */
+export interface ILogger {
+  log(message: string): void;
+  error(message: string, error?: unknown): void;
+}
+

src/interfaces/IProcessManager.ts

@@ -0,0 +1,32 @@
+import {EventEmitter} from 'node:events';
+
+/**
+ * Events emitted by ProcessManager
+ */
+export interface ProcessManagerEvents {
+  data: [Buffer];
+  error: [Error];
+  close: [number | null];
+}
+
+/**
+ * Interface for process management (Interface Segregation Principle)
+ * Separates process lifecycle management from business logic
+ */
+export interface IProcessManager extends EventEmitter {
+  start(command: string, args: string[]): void;
+  stop(): void;
+  isRunning(): boolean;
+  
+  // Event emitter methods with proper typing
+  on(event: 'data', listener: (data: Buffer) => void): this;
+  on(event: 'error', listener: (error: Error) => void): this;
+  on(event: 'close', listener: (code: number | null) => void): this;
+  on(event: string | symbol, listener: (...args: unknown[]) => void): this;
+  
+  emit(event: 'data', data: Buffer): boolean;
+  emit(event: 'error', error: Error): boolean;
+  emit(event: 'close', code: number | null): boolean;
+  emit(event: string | symbol, ...args: unknown[]): boolean;
+}
+

src/interfaces/IProcessSpawner.ts

@@ -0,0 +1,10 @@
+import {ChildProcess} from 'node:child_process';
+
+/**
+ * Interface for spawning child processes (Dependency Inversion Principle)
+ * Allows for dependency injection and easier testing
+ */
+export interface IProcessSpawner {
+  spawn(command: string, args: string[]): ChildProcess;
+}
+

tests/RtmpPush.integration.test.ts

@@ -1,5 +1,5 @@
 import {describe, it, expect, beforeEach, afterEach} from 'bun:test';
-import {RtmpPush} from '../src/RtmpPush';
+import {RtmpPush} from '../src/index.js';
 
 describe('RtmpPush Integration Tests', () => {
   let rtmpPush: RtmpPush;

tests/RtmpPush.test.ts

@@ -1,5 +1,7 @@
 import {describe, it, expect, beforeEach, afterEach} from 'bun:test';
-import {RtmpPush} from '../src/RtmpPush';
+import {RtmpPush} from '../src/index.js';
+import type {ICommandBuilder, IProcessManager, ILogger, IProcessSpawner} from '../src/index.js';
+import {CommandBuilder, ProcessManager, ProcessSpawner, ConsoleLogger} from '../src/index.js';
 
 describe('RtmpPush', () => {
   let rtmpPush: RtmpPush;
@@ -252,5 +254,179 @@ describe('RtmpPush', () => {
         expect(error).toBeInstanceOf(Error);
       }
     });
+
+    it('should throw error when starting an already running stream', () => {
+      const streamKey = 'test-stream';
+      const capabilities = ['h264'];
+
+      // Mock process manager that reports as running
+      const mockProcessManager: IProcessManager = {
+        isRunning: () => true,
+        start: () => {},
+        stop: () => {},
+        on: () => mockProcessManager,
+        emit: () => false,
+        once: () => mockProcessManager,
+        off: () => mockProcessManager,
+        removeListener: () => mockProcessManager,
+        removeAllListeners: () => mockProcessManager,
+        addListener: () => mockProcessManager,
+        setMaxListeners: () => mockProcessManager,
+        getMaxListeners: () => 10,
+        listeners: () => [],
+        rawListeners: () => [],
+        listenerCount: () => 0,
+        prependListener: () => mockProcessManager,
+        prependOnceListener: () => mockProcessManager,
+        eventNames: () => []
+      } as IProcessManager;
+
+      const customRtmpPush = new RtmpPush(mockMediaSourceUri, mockRtmpIngestUri, {
+        processManager: mockProcessManager
+      });
+
+      expect(() => {
+        customRtmpPush.start(streamKey, capabilities);
+      }).toThrow('Stream is already running');
+    });
+  });
+
+  describe('Dependency Injection', () => {
+    it('should accept custom command builder', () => {
+      const mockCommandBuilder: ICommandBuilder = {
+        buildCommand: (mediaUri, rtmpUri, streamKey, capabilities) => {
+          expect(mediaUri).toBe(mockMediaSourceUri);
+          expect(rtmpUri).toBe(mockRtmpIngestUri);
+          expect(streamKey).toBe('test-key');
+          expect(capabilities).toEqual(['h264']);
+          return ['custom-ffmpeg', '-custom', 'args'];
+        }
+      };
+
+      const customRtmpPush = new RtmpPush(mockMediaSourceUri, mockRtmpIngestUri, {
+        commandBuilder: mockCommandBuilder
+      });
+
+      expect(customRtmpPush.mediaSourceUri).toBe(mockMediaSourceUri);
+      expect(customRtmpPush.rtmpIngestUri).toBe(mockRtmpIngestUri);
+    });
+
+    it('should accept custom process manager', () => {
+      let startCalled = false;
+      const mockProcessManager: IProcessManager = {
+        isRunning: () => false,
+        start: (command, args) => {
+          startCalled = true;
+          expect(command).toBe('ffmpeg');
+          expect(args).toBeInstanceOf(Array);
+        },
+        stop: () => {},
+        on: () => mockProcessManager,
+        emit: () => false,
+        once: () => mockProcessManager,
+        off: () => mockProcessManager,
+        removeListener: () => mockProcessManager,
+        removeAllListeners: () => mockProcessManager,
+        addListener: () => mockProcessManager,
+        setMaxListeners: () => mockProcessManager,
+        getMaxListeners: () => 10,
+        listeners: () => [],
+        rawListeners: () => [],
+        listenerCount: () => 0,
+        prependListener: () => mockProcessManager,
+        prependOnceListener: () => mockProcessManager,
+        eventNames: () => []
+      } as IProcessManager;
+
+      const customRtmpPush = new RtmpPush(mockMediaSourceUri, mockRtmpIngestUri, {
+        processManager: mockProcessManager
+      });
+
+      try {
+        customRtmpPush.start('test-key', ['h264']);
+        expect(startCalled).toBe(true);
+      } catch (error) {
+        // If ffmpeg is not available, that's expected
+        expect(error).toBeInstanceOf(Error);
+      }
+    });
+
+    it('should accept custom ffmpeg command', () => {
+      const customRtmpPush = new RtmpPush(mockMediaSourceUri, mockRtmpIngestUri, {
+        ffmpegCommand: 'custom-ffmpeg-path'
+      });
+
+      expect(customRtmpPush.mediaSourceUri).toBe(mockMediaSourceUri);
+      expect(customRtmpPush.rtmpIngestUri).toBe(mockRtmpIngestUri);
+    });
+
+    it('should use default implementations when none provided', () => {
+      const defaultRtmpPush = new RtmpPush(mockMediaSourceUri, mockRtmpIngestUri);
+      expect(defaultRtmpPush).toBeInstanceOf(RtmpPush);
+      expect(defaultRtmpPush.mediaSourceUri).toBe(mockMediaSourceUri);
+      expect(defaultRtmpPush.rtmpIngestUri).toBe(mockRtmpIngestUri);
+    });
+  });
+
+  describe('Process Manager Events', () => {
+    it('should provide access to process manager for event handling', () => {
+      const processManager = rtmpPush.getProcessManager();
+      expect(processManager).toBeDefined();
+      expect(typeof processManager.on).toBe('function');
+      expect(typeof processManager.emit).toBe('function');
+    });
+
+    it('should allow listening to process events', () => {
+      const processManager = rtmpPush.getProcessManager();
+      let dataReceived = false;
+      let errorReceived = false;
+      let closeReceived = false;
+
+      processManager.on('data', () => {
+        dataReceived = true;
+      });
+
+      processManager.on('error', () => {
+        errorReceived = true;
+      });
+
+      processManager.on('close', () => {
+        closeReceived = true;
+      });
+
+      // Events would be emitted by the actual process, but we can verify the listeners are set up
+      expect(typeof processManager.on).toBe('function');
+    });
+  });
+
+  describe('CommandBuilder', () => {
+    it('should build correct FFmpeg commands', () => {
+      const builder = new CommandBuilder();
+      const command = builder.buildCommand(
+        'https://example.com/video.ts',
+        'rtmp://ingest.example.com/ingest',
+        'test-key',
+        ['h264', 'aac']
+      );
+
+      expect(command[0]).toBe('ffmpeg');
+      expect(command).toContain('-re');
+      expect(command).toContain('-i');
+      expect(command).toContain('https://example.com/video.ts');
+      expect(command[command.length - 1]).toContain('rtmp://ingest.example.com/ingest/test-key');
+      expect(command[command.length - 1]).toContain('capabilities=h264,aac');
+    });
+
+    it('should use custom ffmpeg command when provided', () => {
+      const builder = new CommandBuilder('custom-ffmpeg');
+      const command = builder.buildCommand(
+        'https://example.com/video.ts',
+        'rtmp://ingest.example.com/ingest',
+        'test-key',
+        ['h264']
+      );
+
+      expect(command[0]).toBe('custom-ffmpeg');
+    });
   });
 });

tsconfig.build.json

@@ -0,0 +1,17 @@
+{
+  "extends": "./tsconfig.json",
+  "compilerOptions": {
+    "noEmit": false,
+    "declaration": true,
+    "emitDeclarationOnly": true,
+    "outDir": "./dist/types",
+    "rootDir": "./src",
+    "moduleResolution": "node",
+    "module": "ESNext",
+    "allowImportingTsExtensions": false,
+    "declarationMap": true
+  },
+  "include": ["src/**/*"],
+  "exclude": ["node_modules", "dist", "tests"]
+}
+