小程序后端接入微信登录与家长头像能力

2026-04-16 18:19:19 +08:00
parent db888df50f
commit 2526365af1
10 changed files with 515 additions and 77 deletions
--- a/mini-program/app/service/avatar_storage.py
+++ b/mini-program/app/service/avatar_storage.py
@@ -0,0 +1,134 @@
+from dataclasses import dataclass
+from datetime import UTC, datetime
+from pathlib import Path
+from uuid import uuid4
+
+try:
+    from qcloud_cos import CosConfig, CosS3Client
+except ModuleNotFoundError:  # pragma: no cover - exercised in runtime env
+    CosConfig = None
+    CosS3Client = None
+
+from app.settings import settings
+
+
+_CONTENT_TYPE_TO_EXT = {
+    "image/jpeg": "jpg",
+    "image/png": "png",
+    "image/webp": "webp",
+}
+_EXTENSION_ALIASES = {
+    ".jpg": "jpg",
+    ".jpeg": "jpg",
+    ".png": "png",
+    ".webp": "webp",
+}
+_EXT_TO_CONTENT_TYPE = {
+    "jpg": "image/jpeg",
+    "png": "image/png",
+    "webp": "image/webp",
+}
+
+
+class AvatarStorageError(Exception):
+    def __init__(self, message: str, status_code: int = 400) -> None:
+        super().__init__(message)
+        self.status_code = status_code
+
+
+@dataclass(frozen=True)
+class StoredAvatar:
+    file_key: str
+
+
+class AvatarStorageService:
+    def __init__(self) -> None:
+        self._client = None
+
+    def upload_avatar(
+        self,
+        *,
+        user_id: int,
+        filename: str | None,
+        content_type: str | None,
+        content: bytes,
+    ) -> StoredAvatar:
+        self._assert_ready()
+        normalized_ext = self._normalize_extension(filename=filename, content_type=content_type)
+        if not content:
+            raise AvatarStorageError("avatar file is empty")
+        if len(content) > settings.cos_avatar_max_bytes:
+            raise AvatarStorageError("avatar file too large", status_code=413)
+
+        key = self._build_key(user_id=user_id, extension=normalized_ext)
+        self._get_client().put_object(
+            Bucket=settings.cos_bucket_ava,
+            Body=content,
+            Key=key,
+            ContentType=_EXT_TO_CONTENT_TYPE[normalized_ext],
+            EnableMD5=False,
+        )
+        return StoredAvatar(file_key=key)
+
+    def get_avatar_url(self, file_key: str) -> str:
+        self._assert_ready()
+        if not file_key:
+            raise AvatarStorageError("avatar file key is required", status_code=500)
+        return self._get_client().get_presigned_url(
+            Bucket=settings.cos_bucket_ava,
+            Key=file_key,
+            Method="GET",
+            Expired=settings.cos_avatar_url_expire_seconds,
+        )
+
+    def delete_avatar(self, file_key: str) -> None:
+        self._assert_ready()
+        if not file_key:
+            return
+        self._get_client().delete_object(Bucket=settings.cos_bucket_ava, Key=file_key)
+
+    def _assert_ready(self) -> None:
+        if CosConfig is None or CosS3Client is None:
+            raise AvatarStorageError("COS SDK is not installed", status_code=500)
+
+        required_pairs = {
+            "COS_SECRET_ID": settings.cos_secret_id,
+            "COS_SECRET_KEY": settings.cos_secret_key,
+            "COS_REGION": settings.cos_region,
+            "COS_BUCKET_AVA": settings.cos_bucket_ava,
+        }
+        missing = [key for key, value in required_pairs.items() if not value]
+        if missing:
+            raise AvatarStorageError(
+                f"missing COS avatar config: {', '.join(missing)}",
+                status_code=500,
+            )
+
+    def _get_client(self):
+        if self._client is None:
+            config = CosConfig(
+                Region=settings.cos_region,
+                SecretId=settings.cos_secret_id,
+                SecretKey=settings.cos_secret_key,
+                Scheme="https",
+            )
+            self._client = CosS3Client(config)
+        return self._client
+
+    def _normalize_extension(self, *, filename: str | None, content_type: str | None) -> str:
+        if content_type in _CONTENT_TYPE_TO_EXT:
+            return _CONTENT_TYPE_TO_EXT[content_type]
+
+        suffix = Path(filename or "").suffix.lower()
+        if suffix in _EXTENSION_ALIASES:
+            return _EXTENSION_ALIASES[suffix]
+
+        raise AvatarStorageError("unsupported avatar file type", status_code=415)
+
+    def _build_key(self, *, user_id: int, extension: str) -> str:
+        prefix = settings.cos_avatar_prefix.strip("/") or "avatars"
+        now = datetime.now(UTC)
+        return (
+            f"{prefix}/{user_id}/{now.strftime('%Y/%m/%d')}/"
+            f"{uuid4().hex}.{extension}"
+        )