Midjourney API 快速开始

{
  "taskType": "mj_txt2img",
  "prompt": "未来主义城市景观，有飞行汽车和霓虹灯光",
  "aspectRatio": "16:9",
  "version": "7"
}

class MidjourneyAPI {
  constructor(apiKey) {
    this.apiKey = apiKey;
    this.baseUrl = 'https://api.midapi.ai/api/v1/mj';
  }
  
  async generateImage(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(`生成失败: ${result.msg || '未知错误'}`);
    }
    
    return result.data.taskId;
  }
  
  async waitForCompletion(taskId, maxWaitTime = 600000) { // 最长等待10分钟
    const startTime = Date.now();
    
    while (Date.now() - startTime < maxWaitTime) {
      const status = await this.getTaskStatus(taskId);
      
      switch (status.successFlag) {
        case 0:
          console.log('任务生成中，继续等待...');
          break;
          
        case 1:
          console.log('生成成功完成！');
          return status.resultInfoJson;
          
        case 2:
          const taskError = status.errorMessage || '任务生成失败';
          console.error('任务生成失败:', taskError);
          if (status.errorCode) {
            console.error('错误代码:', status.errorCode);
          }
          throw new Error(taskError);
          
        case 3:
          const generateError = status.errorMessage || '任务创建成功但生成失败';
          console.error('生成失败:', generateError);
          if (status.errorCode) {
            console.error('错误代码:', status.errorCode);
          }
          throw new Error(generateError);
          
        default:
          console.log(`未知状态: ${status.successFlag}`);
          if (status.errorMessage) {
            console.error('错误信息:', status.errorMessage);
          }
          break;
      }
      
      // 等待30秒后再次检查
      await new Promise(resolve => setTimeout(resolve, 30000));
    }
    
    throw new Error('生成超时');
  }
  
  async getTaskStatus(taskId) {
    const response = await fetch(`${this.baseUrl}/record-info?taskId=${taskId}`, {
      method: 'GET',
      headers: {
        'Authorization': `Bearer ${this.apiKey}`
      }
    });
    
    const result = await response.json();
    if (!response.ok || result.code !== 200) {
      throw new Error(`查询状态失败: ${result.msg || '未知错误'}`);
    }
    
    return result.data;
  }
  
  async upscaleImage(taskId, index) {
    const response = await fetch(`${this.baseUrl}/upscale`, {
      method: 'POST',
      headers: {
        'Authorization': `Bearer ${this.apiKey}`,
        'Content-Type': 'application/json'
      },
      body: JSON.stringify({
        taskId,
        index
      })
    });
    
    const result = await response.json();
    if (!response.ok || result.code !== 200) {
      throw new Error(`放大失败: ${result.msg || '未知错误'}`);
    }
    
    return result.data.taskId;
  }
}

// 使用示例
async function main() {
  const api = new MidjourneyAPI('YOUR_API_KEY');
  
  try {
    // 文本转图像生成
    console.log('开始图像生成...');
    const taskId = await api.generateImage({
      taskType: 'mj_txt2img',
      prompt: '一座雄伟的古老城堡，矗立在云雾缭绕的山峰之上，夕阳西下，金光洒在城堡的石墙上',
      speed: 'fast',
      aspectRatio: '16:9',
      version: '7',
      stylization: 500
    });
    
    // 等待完成
    console.log(`任务ID: ${taskId}。等待完成...`);
    const result = await api.waitForCompletion(taskId);
    
    console.log('图像生成成功！');
    console.log('生成的图像数量:', result.resultUrls.length);
    result.resultUrls.forEach((urlInfo, index) => {
      console.log(`图像 ${index + 1}: ${urlInfo.resultUrl}`);
    });
    
    // 放大第一张图像
    console.log('\n开始放大第一张图像...');
    const upscaleTaskId = await api.upscaleImage(taskId, 1);
    
    const upscaleResult = await api.waitForCompletion(upscaleTaskId);
    console.log('图像放大成功！');
    console.log('放大后图像:', upscaleResult.resultUrls[0].resultUrl);
    
  } catch (error) {
    console.error('错误:', error.message);
  }
}

main();