POST https://imagedescriber.online/api/openapi/describe-image

{
    "code": 200,
    "data": {
        "content": "Markdown 形式の画像の詳細な説明..."
    },
    "succeed": true,
    "msg": "成功"
}

import fs from 'fs';

// Get image base64 data: Server-side implementation
const buffer = await fs.readFileSync("/temp/test.jpg");
const base64Image = buffer.toString('base64');
const imageBase64Data = `data:image/jpeg;base64,${base64Image}`;

// Get image base64 data: Client-side implementation
const file:File = /* file from input or drop event */;
const arrayBuffer = await file.arrayBuffer();
const bytes = new Uint8Array(arrayBuffer);
const base64Image = btoa(String.fromCharCode.apply(null, bytes as any));
const imageBase64Data = `data:${file.type};base64,${base64Image}`;

// Request Body
const formData = new FormData();
formData.append('imageBase64Data', imageBase64Data);
formData.append('lang', 'en');
formData.append('prompt', 'Summarize the content of the picture in one sentence, then describe in detail what is in the picture, including objects, people, animals, and the atmosphere and mood of the picture');

// Signature
const appid = "app_1234567";
const secret = "sk_a8f3dbb3...";
const timestamp = Date.now().toString();
const nonce = crypto.randomBytes(4).toString('hex');

const signStr = buildSignString(appid, timestamp, nonce); // See subsequent code for function implementation
const sign = await sign(signStr, secret); // See subsequent code for function implementation

// Do Request
const response = await fetch('https://imagedescriber.online/api/openapi/describe-image', {
  method: 'POST',
  headers: {
      'appid': appid,
      'timestamp': timestamp,
      'nonce': nonce,
      'signature': sign
    },
    body: formData
});

const result = await response.json();
console.log(result);

function buildSignString(appId: string, timestamp: string, nonce: string): string {
  return [appId, timestamp, nonce].join('-');
}

async function sign(message: string, secret: string): Promise<string> {
  const encoder = new TextEncoder();
  const keyData = encoder.encode(secret);
  const messageData = encoder.encode(message);

  const key = await crypto.subtle.importKey(
    'raw',
    keyData,
    { name: 'HMAC', hash: 'SHA-256' },
    false,
    ['sign']
  );

  const signatureData = await crypto.subtle.sign(
    'HMAC',
    key,
    messageData
  );

  return btoa(String.fromCharCode.apply(null, Array.from(new Uint8Array(signatureData))));
}