以 API 提供的 Euphona 引擎

1：建立檔案並取得上傳目標

curl -X POST https://api.euphonaai.com/v1/files \
  -H "Authorization: Bearer $EUPHONA_API_KEY" \
  -H "Idempotency-Key: $(uuidgen)" \
  -H "Content-Type: application/json" \
  -d '{"filename":"take-07.wav","bytes":58210044,"content_type":"audio/wav"}'

{
  "id": "file_8Kd2mQ...",
  "object": "file",
  "status": "awaiting_upload",
  "upload": { "protocol": "...", "url": "https://files.euphonaai.com/...", "expires_at": "..." }
}

2：把位元組送到 files.，而不是送給我們

# 請讀取 upload.protocol：不要自行假設。可續傳的機制是介面規格內的
# 實作選擇，可能在不升級主要版本的情況下變更，這正是它是一個欄位、而不是寫在文件裡的原因。

3：觀察工作

curl -N https://api.euphonaai.com/v1/jobs/job_4Rb.../events \
  -H "Authorization: Bearer $EUPHONA_API_KEY"

event: job.progress
data: {"status":"analyzing","stage":"analyze","progress":{"fraction":0.4}}

event: job.completed
data: {"status":"succeeded","result":{...},"metering":{"pool":"payg","charged_minutes":3.4}}

4：以工作本身為準進行核對

curl https://api.euphonaai.com/v1/jobs/job_4Rb... \
  -H "Authorization: Bearer $EUPHONA_API_KEY"

{"id":"job_4Rb...","status":"succeeded","result":{...},
 "metering":{"pool":"payg","charged_minutes":3.4}}

# 工作資源是狀態機目前的真實狀態：不論串流顯示了什麼或漏掉了什麼，
# 行動之前都要重新讀取一次。中斷的 SSE 連線會帶著 Last-Event-ID
# 重新連線，不會遺失任何內容。

驗證一次傳送（Node.js）

import { createHmac, timingSafeEqual } from "node:crypto";

// 請原樣傳入收到的原始主體：剖析後再序列化的 JSON
// 並不是被簽章的那則訊息。
export function verifyEuphonaSignature(rawBody, header, secret, now = Date.now() / 1000) {
  const parts = header.split(",").map((part) => part.trim().split("="));
  const t = Number(parts.find(([key]) => key === "t")?.[1]);
  const signatures = parts.filter(([key]) => key === "v1").map(([, value]) => value);
  if (!Number.isFinite(t) || Math.abs(now - t) > 300) return false;
  const expected = createHmac("sha256", secret).update(`${t}.${rawBody}`).digest();
  return signatures.some((value) => {
    const given = Buffer.from(value, "hex");
    return given.length === expected.length && timingSafeEqual(given, expected);
  });
}