fix: 统一时间戳为带时区的 UTC datetime，修复跨时区部署时间显示错误

backend/.env.example

@@ -44,6 +44,14 @@ DEFAULT_ADMIN_USERNAME=admin
 DEFAULT_ADMIN_PASSWORD=admin123
 DEFAULT_ADMIN_EMAIL=admin@example.com
 
+# ─────────────────────────────────────────────────────────────────────
+# 时区配置
+# ─────────────────────────────────────────────────────────────────────
+# 服务端使用的时区，影响 ICS 日历文件和邮件通知中的时间显示
+# 数据库始终以 UTC 存储；此配置仅控制服务端生成内容的本地化时区
+# 可用值参见 IANA 时区数据库: https://en.wikipedia.org/wiki/List_of_tz_database_time_zones
+APP_TIMEZONE=Asia/Shanghai
+
 # ─────────────────────────────────────────────────────────────────────
 # 服务器
 # ─────────────────────────────────────────────────────────────────────

backend/app/api/auth.py

@@ -1,5 +1,5 @@
 import secrets
-from datetime import datetime, timedelta
+from datetime import timedelta
 
 from fastapi import APIRouter, Depends, HTTPException, Request, status
 from sqlalchemy.orm import Session
@@ -9,6 +9,7 @@
 from app.core.logging import get_logger
 from app.core.rate_limit import limiter
 from app.core.security import create_access_token, get_password_hash, verify_password
+from app.core.timezone import utc_now
 from app.database import get_db
 from app.models import User
 from app.models.password_reset import PasswordResetToken
@@ -383,7 +384,7 @@ def request_password_reset(
     reset_token = PasswordResetToken(
         user_id=user.id,
         token=token_value,
-        expires_at=datetime.utcnow() + timedelta(hours=1),
+        expires_at=utc_now() + timedelta(hours=1),
     )
     db.add(reset_token)
     db.commit()

backend/app/api/campaigns.py

@@ -1,10 +1,9 @@
-from datetime import datetime
-
 from fastapi import APIRouter, Depends, HTTPException, Query
 from sqlalchemy import func
 from sqlalchemy.orm import Session, joinedload
 
 from app.core.dependencies import get_current_user
+from app.core.timezone import utc_now
 from app.database import get_db
 from app.models import User
 from app.models.campaign import Campaign, CampaignActivity, CampaignContact
@@ -349,7 +348,7 @@ def add_activity(
     )
     db.add(activity)
     # 更新联系人最近跟进时间
-    contact.last_contacted_at = datetime.utcnow()
+    contact.last_contacted_at = utc_now()
     db.commit()
     db.refresh(activity)
     return activity

backend/app/api/community_dashboard.py

@@ -7,14 +7,15 @@
 权限：社区成员（admin / user）均可访问，Superuser 可访问任意社区。
 """
 
-from datetime import datetime, timedelta
+from datetime import timedelta
 
 from fastapi import APIRouter, Depends, HTTPException, status
 from sqlalchemy import case, func, select
 from sqlalchemy.orm import Session, joinedload
 
 from app.core.dependencies import get_current_user, get_user_community_role
 from app.core.logging import get_logger
+from app.core.timezone import utc_now
 from app.database import get_db
 from app.models import Community, User
 from app.models.channel import ChannelConfig
@@ -77,7 +78,7 @@ def get_community_dashboard(
             detail="社区不存在",
         )
 
-    now = datetime.utcnow()
+    now = utc_now()
 
     # ── 1. 指标卡片聚合（单批查询）──────────────────────────────────────
 
@@ -432,7 +433,7 @@ def get_superuser_overview(
             detail="仅平台超级管理员可访问",
         )
 
-    now = datetime.utcnow()
+    now = utc_now()
     communities = db.query(Community).order_by(Community.created_at.desc()).all()
 
     # 批量查询各社区统计（避免 N+1）

backend/app/api/publish.py

@@ -1,11 +1,11 @@
 import os
-from datetime import datetime
 
 from fastapi import APIRouter, Depends, HTTPException
 from sqlalchemy.orm import Session
 
 from app.config import settings
 from app.core.dependencies import get_current_community
+from app.core.timezone import utc_now
 from app.database import get_db
 from app.models.content import Content
 from app.models.publish_record import PublishRecord
@@ -141,7 +141,7 @@ def publish_to_hugo(content_id: int, db: Session = Depends(get_db)):
         channel="hugo",
         status="published",
         platform_url=file_path,
-        published_at=datetime.utcnow(),
+        published_at=utc_now(),
         community_id=community_id,
     )
     db.add(record)

backend/app/config.py

@@ -60,6 +60,9 @@ def cors_origins_list(self) -> list[str]:
     UPLOAD_DIR: str = str(Path(__file__).resolve().parent.parent / "uploads")
     MAX_UPLOAD_SIZE: int = 50 * 1024 * 1024  # 50MB
 
+    # Timezone
+    APP_TIMEZONE: str = "Asia/Shanghai"
+
     # Server
     HOST: str = "0.0.0.0"
     PORT: int = 8000

backend/app/core/security.py

@@ -1,9 +1,10 @@
-from datetime import datetime, timedelta
+from datetime import timedelta
 
 from jose import JWTError, jwt
 from passlib.context import CryptContext
 
 from app.config import settings
+from app.core.timezone import utc_now
 
 # JWT Configuration — single source from settings
 SECRET_KEY = settings.JWT_SECRET_KEY
@@ -60,9 +61,9 @@ def create_access_token(data: dict, expires_delta: timedelta | None = None) -> s
     """Create a JWT access token."""
     to_encode = data.copy()
     if expires_delta:
-        expire = datetime.utcnow() + expires_delta
+        expire = utc_now() + expires_delta
     else:
-        expire = datetime.utcnow() + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
+        expire = utc_now() + timedelta(minutes=ACCESS_TOKEN_EXPIRE_MINUTES)
     to_encode.update({"exp": expire})
     encoded_jwt = jwt.encode(to_encode, SECRET_KEY, algorithm=ALGORITHM)
     return encoded_jwt

backend/app/core/timezone.py

@@ -0,0 +1,21 @@
+from datetime import UTC, datetime
+from zoneinfo import ZoneInfo
+
+
+def utc_now() -> datetime:
+    """返回当前 UTC 时间（带时区信息）。"""
+    return datetime.now(UTC)
+
+
+def get_app_tz() -> ZoneInfo:
+    """返回配置的应用时区对象。"""
+    from app.config import settings
+
+    return ZoneInfo(settings.APP_TIMEZONE)
+
+
+def to_app_tz(dt: datetime) -> datetime:
+    """将 datetime 转换为应用时区。用于服务端输出（邮件、ICS 等）。"""
+    if dt.tzinfo is None:
+        dt = dt.replace(tzinfo=UTC)
+    return dt.astimezone(get_app_tz())

backend/app/models/audit.py

@@ -1,8 +1,7 @@
-from datetime import datetime
-
 from sqlalchemy import JSON, Column, DateTime, ForeignKey, Integer, String
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 
 
@@ -17,7 +16,7 @@ class AuditLog(Base):
     resource_id = Column(Integer, nullable=True)  # ID of the affected resource
     details = Column(JSON, default=dict)  # Additional details about the action
     ip_address = Column(String(50), nullable=True)
-    created_at = Column(DateTime, default=datetime.utcnow, index=True)
+    created_at = Column(DateTime(timezone=True), default=utc_now, index=True)
 
     # Relationships
     user = relationship("User", back_populates="audit_logs")

backend/app/models/campaign.py

@@ -1,8 +1,7 @@
-from datetime import datetime
-
 from sqlalchemy import Column, Date, DateTime, ForeignKey, Integer, String, Text
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 
 
@@ -19,8 +18,8 @@ class Campaign(Base):
     owner_id = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
     start_date = Column(Date, nullable=True)
     end_date = Column(Date, nullable=True)
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
+    updated_at = Column(DateTime(timezone=True), default=utc_now, onupdate=utc_now)
 
     contacts = relationship("CampaignContact", back_populates="campaign", cascade="all, delete-orphan")
     activities = relationship("CampaignActivity", back_populates="campaign", cascade="all, delete-orphan")
@@ -35,7 +34,7 @@ class CampaignContact(Base):
     status = Column(String(50), nullable=False, default="pending")   # pending/contacted/responded/converted/declined
     channel = Column(String(50), nullable=True)                       # email/wechat/phone/in_person/other
     added_by = Column(String(50), nullable=False, default="manual")  # manual/event_import/ecosystem_import/csv_import
-    last_contacted_at = Column(DateTime, nullable=True)
+    last_contacted_at = Column(DateTime(timezone=True), nullable=True)
     notes = Column(Text, nullable=True)
     assigned_to_id = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
 
@@ -53,7 +52,7 @@ class CampaignActivity(Base):
     content = Column(Text, nullable=True)
     outcome = Column(String(300), nullable=True)
     operator_id = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
-    created_at = Column(DateTime, default=datetime.utcnow)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
 
     campaign = relationship("Campaign", back_populates="activities")
     person = relationship("PersonProfile")

backend/app/models/committee.py

@@ -1,5 +1,3 @@
-from datetime import datetime
-
 from sqlalchemy import (
     JSON,
     Boolean,
@@ -14,6 +12,7 @@
 )
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 
 
@@ -38,9 +37,9 @@ class Committee(Base):
     notification_email = Column(String(200), nullable=True)
     notification_wechat = Column(String(100), nullable=True)
 
-    established_at = Column(DateTime, nullable=True)
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    established_at = Column(DateTime(timezone=True), nullable=True)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
+    updated_at = Column(DateTime(timezone=True), default=utc_now, onupdate=utc_now)
 
     # Relationships
     community = relationship("Community", back_populates="committees")
@@ -91,9 +90,9 @@ class CommitteeMember(Base):
     bio = Column(Text, nullable=True)
     avatar_url = Column(String(500), nullable=True)
 
-    joined_at = Column(DateTime, default=datetime.utcnow)
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    joined_at = Column(DateTime(timezone=True), default=utc_now)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
+    updated_at = Column(DateTime(timezone=True), default=utc_now, onupdate=utc_now)
 
     # 关联人脉档案（可为空，表示尚未与 PersonProfile 匹配）
     person_id = Column(

backend/app/models/community.py

@@ -1,8 +1,7 @@
-from datetime import datetime
-
 from sqlalchemy import JSON, Boolean, Column, DateTime, Integer, String, Text
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 from app.models.user import community_users
 
@@ -18,8 +17,8 @@ class Community(Base):
     logo_url = Column(String(500), nullable=True)
     settings = Column(JSON, default=dict)  # Community-level settings
     is_active = Column(Boolean, default=True)
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
+    updated_at = Column(DateTime(timezone=True), default=utc_now, onupdate=utc_now)
 
     # Relationships
     members = relationship(

backend/app/models/content.py

@@ -1,9 +1,8 @@
-from datetime import datetime
-
 from sqlalchemy import JSON, Boolean, Column, DateTime, ForeignKey, Integer, String, Table, Text
 from sqlalchemy import Enum as SAEnum
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 
 # Association table for content → community (multi-community support)
@@ -14,7 +13,7 @@
     Column("content_id", Integer, ForeignKey("contents.id", ondelete="CASCADE"), nullable=False, index=True),
     Column("community_id", Integer, ForeignKey("communities.id", ondelete="CASCADE"), nullable=False, index=True),
     Column("is_primary", Boolean, server_default="1"),
-    Column("linked_at", DateTime, default=datetime.utcnow),
+    Column("linked_at", DateTime(timezone=True), default=utc_now),
     Column("linked_by_id", Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True),
 )
 
@@ -25,7 +24,7 @@
     Column("id", Integer, primary_key=True),
     Column("content_id", Integer, ForeignKey("contents.id", ondelete="CASCADE"), nullable=False),
     Column("user_id", Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False),
-    Column("added_at", DateTime, default=datetime.utcnow),
+    Column("added_at", DateTime(timezone=True), default=utc_now),
 )
 
 
@@ -36,7 +35,7 @@
     Column("id", Integer, primary_key=True),
     Column("content_id", Integer, ForeignKey("contents.id", ondelete="CASCADE"), nullable=False, index=True),
     Column("user_id", Integer, ForeignKey("users.id", ondelete="CASCADE"), nullable=False, index=True),
-    Column("assigned_at", DateTime, default=datetime.utcnow),
+    Column("assigned_at", DateTime(timezone=True), default=utc_now),
     Column("assigned_by_user_id", Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True),
 )
 
@@ -71,8 +70,8 @@ class Content(Base):
     # Calendar/scheduling field
     scheduled_publish_at = Column(DateTime, nullable=True, index=True)
 
-    created_at = Column(DateTime, default=datetime.utcnow)
-    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
+    updated_at = Column(DateTime(timezone=True), default=utc_now, onupdate=utc_now)
 
     publish_records = relationship("PublishRecord", back_populates="content", cascade="all, delete-orphan")
     community = relationship("Community", back_populates="contents")

backend/app/models/ecosystem.py

@@ -1,8 +1,7 @@
-from datetime import datetime
-
 from sqlalchemy import JSON, Boolean, Column, DateTime, ForeignKey, Integer, String, Text
 from sqlalchemy.orm import relationship
 
+from app.core.timezone import utc_now
 from app.database import Base
 
 
@@ -18,9 +17,9 @@ class EcosystemProject(Base):
     description = Column(Text, nullable=True)
     tags = Column(JSON, default=list)
     is_active = Column(Boolean, default=True)
-    last_synced_at = Column(DateTime, nullable=True)
+    last_synced_at = Column(DateTime(timezone=True), nullable=True)
     added_by_id = Column(Integer, ForeignKey("users.id", ondelete="SET NULL"), nullable=True)
-    created_at = Column(DateTime, default=datetime.utcnow)
+    created_at = Column(DateTime(timezone=True), default=utc_now)
 
     contributors = relationship(
         "EcosystemContributor",
@@ -44,7 +43,7 @@ class EcosystemContributor(Base):
     followers = Column(Integer, nullable=True)
     # 关联到人脉库
     person_id = Column(Integer, ForeignKey("person_profiles.id", ondelete="SET NULL"), nullable=True, index=True)
-    last_synced_at = Column(DateTime, default=datetime.utcnow)
+    last_synced_at = Column(DateTime(timezone=True), default=utc_now)
 
     project = relationship("EcosystemProject", back_populates="contributors")
     person = relationship("PersonProfile")