Runway API Quickstart

{
  "prompt": "A majestic eagle soaring through mountain clouds at sunset",
  "duration": 5,
  "quality": "720p",
  "aspectRatio": "16:9"
}

class RunwayAPI {
  constructor(apiKey) {
    this.apiKey = apiKey;
    this.baseUrl = 'https://api.kie.ai/api/v1/runway';
  }
  
  async generateVideo(options) {
    const response = await fetch(`${this.baseUrl}/generate`, {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${this.apiKey}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify(options)
    });
    
    const result = await response.json();
    if (!response.ok || result.code !== 200) {
      throw new Error(`Generation failed: ${result.msg || 'Unknown error'}`);
    }
    
    return result.data.taskId;
  }
  
  async waitForCompletion(taskId, maxWaitTime = 600000) { // Max wait 10 minutes
    const startTime = Date.now();
    
    while (Date.now() - startTime < maxWaitTime) {
      const status = await this.getTaskStatus(taskId);
      
      switch (status.state) {
        case 'wait':
          console.log('Task is waiting, continue waiting...');
          break;
          
        case 'queueing':
          console.log('Task is queueing, continue waiting...');
          break;
          
        case 'generating':
          console.log('Task is generating, continue waiting...');
          break;
          
        case 'success':
          console.log('Generation completed successfully!');
          return status;
          
        case 'fail':
          const error = status.failMsg || 'Task generation failed';
          console.error('Task generation failed:', error);
          throw new Error(error);
          
        default:
          console.log(`Unknown status: ${status.state}`);
          if (status.failMsg) {
            console.error('Error message:', status.failMsg);
          }
          break;
      }
      
      // Wait 30 seconds before checking again
      await new Promise(resolve => setTimeout(resolve, 30000));
    }
    
    throw new Error('Generation timeout');
  }
  
  async getTaskStatus(taskId) {
    const response = await fetch(`${this.baseUrl}/record-detail?taskId=${taskId}`, {
      method: 'GET',
      headers: {
        'Authorization': `Bearer ${this.apiKey}`
      }
    });
    
    const result = await response.json();
    if (!response.ok || result.code !== 200) {
      throw new Error(`Status check failed: ${result.msg || 'Unknown error'}`);
    }
    
    return result.data;
  }
  
  async extendVideo(taskId, prompt, quality = '720p') {
    const response = await fetch(`${this.baseUrl}/extend`, {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${this.apiKey}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        taskId,
        prompt,
        quality
      })
    });
    
    const result = await response.json();
    if (!response.ok || result.code !== 200) {
      throw new Error(`Extension failed: ${result.msg || 'Unknown error'}`);
    }
    
    return result.data.taskId;
  }
}

// Usage example
async function main() {
  const api = new RunwayAPI('YOUR_API_KEY');
  
  try {
    // Text-to-video generation
    console.log('Starting video generation...');
    const taskId = await api.generateVideo({
      prompt: 'A fluffy orange cat dancing energetically in a colorful room with disco lights',
      duration: 5,
      quality: '720p',
      aspectRatio: '16:9',
      waterMark: ''
    });
    
    // Wait for completion
    console.log(`Task ID: ${taskId}. Waiting for completion...`);
    const result = await api.waitForCompletion(taskId);
    
    console.log('Video generation successful!');
    console.log('Video URL:', result.videoInfo.videoUrl);
    console.log('Thumbnail URL:', result.videoInfo.imageUrl);
    
    // Extend video
    console.log('\nStarting video extension...');
    const extendTaskId = await api.extendVideo(taskId, 'The cat spins around with increasing energy and excitement', '720p');
    
    const extendResult = await api.waitForCompletion(extendTaskId);
    console.log('Video extension successful!');
    console.log('Extended video URL:', extendResult.videoInfo.videoUrl);
    
  } catch (error) {
    console.error('Error:', error.message);
  }
}

main();