Implement webhook

2026-08-07 14:08:49 +08:00
parent 39ee5ef96e
commit b2e99baa19
14 changed files with 886 additions and 34 deletions
@@ -0,0 +1,86 @@
+"""Serialize, sign and send one webhook event."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+import hashlib
+import hmac
+import json
+import time
+from typing import Any
+
+import httpx
+
+from services.webhooks.security import validate_webhook_url
+
+
+WEBHOOK_TIMEOUT_SECONDS = 10.0
+
+
+@dataclass(frozen=True)
+class DeliveryResult:
+    ok: bool
+    status_code: int | None
+    latency_ms: int
+    error: str = ""
+
+
+def canonical_json(payload: dict[str, Any]) -> bytes:
+    return json.dumps(
+        payload,
+        ensure_ascii=False,
+        separators=(",", ":"),
+        sort_keys=True,
+    ).encode("utf-8")
+
+
+def webhook_signature(secret: str, timestamp: str, body: bytes) -> str:
+    signed = timestamp.encode("ascii") + b"." + body
+    digest = hmac.new(secret.encode("utf-8"), signed, hashlib.sha256).hexdigest()
+    return f"v1={digest}"
+
+
+def should_retry(status_code: int | None) -> bool:
+    return status_code is None or status_code in {408, 429} or status_code >= 500
+
+
+async def deliver_webhook(
+    *,
+    url: str,
+    secret: str,
+    event_id: str,
+    payload: dict[str, Any],
+) -> DeliveryResult:
+    """Deliver without following redirects; callers decide whether to retry."""
+    safe_url = await validate_webhook_url(url)
+    body = canonical_json(payload)
+    timestamp = str(int(time.time()))
+    headers = {
+        "Content-Type": "application/json",
+        "X-AIVideo-Event-Id": event_id,
+        "X-AIVideo-Timestamp": timestamp,
+        "X-AIVideo-Signature": webhook_signature(secret, timestamp, body),
+    }
+    started = time.monotonic()
+    try:
+        async with httpx.AsyncClient(
+            timeout=WEBHOOK_TIMEOUT_SECONDS,
+            follow_redirects=False,
+        ) as client:
+            response = await client.post(safe_url, content=body, headers=headers)
+        latency_ms = round((time.monotonic() - started) * 1000)
+        if 200 <= response.status_code < 300:
+            return DeliveryResult(True, response.status_code, latency_ms)
+        return DeliveryResult(
+            False,
+            response.status_code,
+            latency_ms,
+            f"目标服务返回 HTTP {response.status_code}",
+        )
+    except httpx.HTTPError as exc:
+        return DeliveryResult(
+            False,
+            None,
+            round((time.monotonic() - started) * 1000),
+            str(exc)[:2048],
+        )