Implement real, working microservices architecture

backend/shared/__init__.py

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+# Shared modules package

backend/shared/constants.py

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+import os
+
+# Database
+DATABASE_URL = os.getenv("DATABASE_URL", "sqlite:///data/database.db")
+
+# JWT
+JWT_SECRET_KEY = os.getenv("JWT_SECRET", "default-jwt-secret-for-development")
+JWT_ALGORITHM = "HS256"
+# Token inactivity expiration - token expires if not used for this duration
+TOKEN_INACTIVITY_EXPIRE_HOURS = 30 * 24  # 30 days of inactivity
+# Maximum token lifetime (safety net) - tokens expire after this regardless of usage
+MAX_TOKEN_LIFETIME_HOURS = 365 * 24  # 1 year maximum
+
+# Owner user
+OWNER_USERNAME = os.getenv("OWNER_USERNAME", "owner")
+
+# Push notifications
+VAPID_PRIVATE_KEY = os.getenv("VAPID_PRIVATE_KEY", "")
+VAPID_PUBLIC_KEY = os.getenv("VAPID_PUBLIC_KEY", "")
+VAPID_SUBJECT = os.getenv("VAPID_SUBJECT", "mailto:admin@example.com")
+
+# Rate limiting
+RATE_LIMIT_REQUESTS = int(os.getenv("RATE_LIMIT_REQUESTS", "100"))
+RATE_LIMIT_WINDOW = int(os.getenv("RATE_LIMIT_WINDOW", "60"))
+
+# File uploads
+MAX_UPLOAD_SIZE = int(os.getenv("MAX_UPLOAD_SIZE", "10485760"))  # 10MB
+ALLOWED_EXTENSIONS = {".jpg", ".jpeg", ".png", ".gif", ".webp", ".mp4", ".mov", ".avi", ".mp3", ".wav"}
+
+# WebSocket
+WEBSOCKET_PING_INTERVAL = 30
+WEBSOCKET_PING_TIMEOUT = 60
+
+# Encryption
+ENCRYPTION_KEY_LENGTH = 32
+ENCRYPTION_NONCE_LENGTH = 12
+
+# Moderation
+PROFANITY_THRESHOLD = float(os.getenv("PROFANITY_THRESHOLD", "0.8"))
+SIMILARITY_THRESHOLD = float(os.getenv("SIMILARITY_THRESHOLD", "0.85"))
+
+# WebRTC
+WEBRTC_ICE_SERVERS = [
+    {"urls": "stun:stun.l.google.com:19302"},
+    {"urls": "stun:stun1.l.google.com:19302"}
+]
+
+# Logging
+LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO")
+LOG_FORMAT = "%(asctime)s - %(name)s - %(levelname)s - %(message)s"

backend/shared/db.py

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+import os
+from sqlalchemy.orm import sessionmaker, Session
+from sqlalchemy import create_engine
+from .constants import DATABASE_URL
+
+# Database connection settings
+POOL_SIZE = int(os.getenv("DB_POOL_SIZE", "20"))
+MAX_OVERFLOW = int(os.getenv("DB_MAX_OVERFLOW", "40"))
+POOL_RECYCLE = int(os.getenv("DB_POOL_RECYCLE", "1800"))
+POOL_TIMEOUT = int(os.getenv("DB_POOL_TIMEOUT", "30"))
+
+POOL_CONFIG = {
+    "pool_size": POOL_SIZE,
+    "max_overflow": MAX_OVERFLOW,
+    "pool_recycle": POOL_RECYCLE,
+    "pool_timeout": POOL_TIMEOUT,
+    "pool_pre_ping": True,
+}
+
+def create_engine_from_url(database_url: str):
+    """Create SQLAlchemy engine from database URL."""
+    connect_args = {}
+    if database_url.startswith("sqlite"):
+        connect_args["check_same_thread"] = False
+
+    engine_kwargs = {
+        "pool_size": POOL_SIZE,
+        "max_overflow": MAX_OVERFLOW,
+        "pool_recycle": POOL_RECYCLE,
+        "pool_pre_ping": True,
+        "pool_timeout": POOL_TIMEOUT,
+    }
+
+    engine = create_engine(
+        database_url,
+        connect_args=connect_args,
+        **engine_kwargs,
+    )
+
+    return engine
+
+# Create engine - this should be called by each service with its own DATABASE_URL
+def get_engine(database_url: str = None):
+    """Get SQLAlchemy engine for the given database URL."""
+    url = database_url or DATABASE_URL
+    return create_engine_from_url(url)
+
+# Session factory - create per service
+def get_session_factory(database_url: str = None):
+    """Get session factory for the given database URL."""
+    engine = get_engine(database_url)
+    return sessionmaker(autocommit=False, autoflush=False, bind=engine)
+
+# Dependency for FastAPI - create per service
+def get_db(database_url: str = None):
+    """FastAPI dependency to get database session."""
+    SessionLocal = get_session_factory(database_url)
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

backend/shared/dependencies.py

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+from datetime import datetime, timedelta
+from fastapi import Depends, HTTPException, Request, status
+from fastapi.security import HTTPAuthorizationCredentials, HTTPBearer
+from sqlalchemy.orm import Session
+from backend.shared.utils import verify_token
+from backend.shared.models import User, DeviceSession
+from backend.shared.db import get_session_factory
+import logging
+
+security = HTTPBearer()
+logger = logging.getLogger("uvicorn.error")
+
+# Зависимость для получения сессии БД
+SessionLocal = get_session_factory()
+
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()
+
+# Зависимость для получения текущего пользователя
+def get_current_user(
+    request: Request,
+    credentials: HTTPAuthorizationCredentials = Depends(security),
+    db: Session = Depends(get_db),
+) -> User:
+    token = credentials.credentials
+    try:
+        payload = verify_token(token)
+    except Exception as e:
+        logger.warning("get_current_user: token verification error: %s", str(e))
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired token",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    if not payload:
+        logger.info("get_current_user: verify_token returned empty payload")
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid or expired token",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+    user = db.query(User).filter(User.id == payload["user_id"]).first()
+    if not user:
+        logger.info("get_current_user: user not found for user_id=%s", payload.get("user_id"))
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="User not found",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    if user.id == 1 and user.suspended:
+        user.suspended = False
+        user.suspension_reason = None
+        db.commit()
+        db.refresh(user)
+
+    # Validate device session from JWT
+    session_id = payload.get("session_id")
+    if not session_id:
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Invalid session",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    device_session = (
+        db.query(DeviceSession)
+        .filter(DeviceSession.user_id == user.id, DeviceSession.session_id == session_id)
+        .first()
+    )
+
+    if not device_session or device_session.revoked:
+        logger.info("get_current_user: session missing/revoked for user_id=%s session_id=%s", user.id, session_id)
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Session revoked or not found",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    # Check if session has been inactive for too long (sliding expiration)
+    from backend.shared.constants import TOKEN_INACTIVITY_EXPIRE_HOURS
+    inactivity_threshold = datetime.now() - timedelta(hours=TOKEN_INACTIVITY_EXPIRE_HOURS)
+    if device_session.last_seen < inactivity_threshold:
+        # Session expired due to inactivity - revoke it
+        device_session.revoked = True
+        db.commit()
+        logger.info("get_current_user: session expired due to inactivity for user_id=%s session_id=%s", user.id, session_id)
+        raise HTTPException(
+            status_code=status.HTTP_401_UNAUTHORIZED,
+            detail="Session expired due to inactivity",
+            headers={"WWW-Authenticate": "Bearer"},
+        )
+
+    # Touch last_seen on valid session (sliding expiration - extends token life)
+    device_session.last_seen = datetime.now()
+    db.commit()
+
+    # Check if user is suspended
+    if user.suspended:
+        logger.info("get_current_user: account suspended for user_id=%s reason=%s", user.id, user.suspension_reason)
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail="Account suspended",
+            headers={"suspension_reason": user.suspension_reason or "No reason provided"},
+        )
+
+    # Check if user is deleted
+    if user.deleted:
+        logger.info("get_current_user: account deleted for user_id=%s", user.id)
+        raise HTTPException(
+            status_code=status.HTTP_403_FORBIDDEN,
+            detail="Account deleted",
+        )
+
+    request.state.current_user = user
+    request.state.session_id = session_id
+
+    return user

backend/shared/models.py

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+from sqlalchemy import Column, Integer, String, Text, DateTime, Boolean, ForeignKey, Float, JSON, BigInteger, UniqueConstraint
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import relationship
+from datetime import datetime
+import json
+from pydantic import BaseModel
+
+Base = declarative_base()
+
+class User(Base):
+    __tablename__ = "users"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    username = Column(String(50), unique=True, index=True, nullable=False)
+    email = Column(String(100), unique=True, index=True, nullable=False)
+    hashed_password = Column(String(255), nullable=False)
+    salt = Column(String(64), nullable=False)
+    display_name = Column(String(100), nullable=True)
+    bio = Column(Text, nullable=True)
+    avatar_url = Column(String(255), nullable=True)
+    is_online = Column(Boolean, default=False)
+    last_seen = Column(DateTime, default=datetime.utcnow)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+    verified = Column(Boolean, default=False)
+    verification_token = Column(String(255), nullable=True)
+    reset_token = Column(String(255), nullable=True)
+    reset_token_expires = Column(DateTime, nullable=True)
+    two_factor_enabled = Column(Boolean, default=False)
+    two_factor_secret = Column(String(255), nullable=True)
+    login_attempts = Column(Integer, default=0)
+    locked_until = Column(DateTime, nullable=True)
+    public_key = Column(Text, nullable=True)
+    private_key = Column(Text, nullable=True)
+    encryption_enabled = Column(Boolean, default=False)
+
+    # Relationships
+    messages = relationship("Message", back_populates="sender", cascade="all, delete-orphan")
+    message_recipients = relationship("MessageRecipient", back_populates="recipient", cascade="all, delete-orphan")
+    devices = relationship("Device", back_populates="user", cascade="all, delete-orphan")
+    push_subscriptions = relationship("PushSubscription", back_populates="user", cascade="all, delete-orphan")
+
+class Message(Base):
+    __tablename__ = "messages"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    sender_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, index=True)
+    content = Column(Text, nullable=False)
+    content_type = Column(String(50), default="text")
+    encrypted_content = Column(Text, nullable=True)
+    signature = Column(Text, nullable=True)
+    timestamp = Column(DateTime, default=datetime.utcnow, index=True)
+    edited_at = Column(DateTime, nullable=True)
+    edited = Column(Boolean, default=False)
+    deleted = Column(Boolean, default=False)
+    reply_to_id = Column(BigInteger, ForeignKey("messages.id"), nullable=True)
+    thread_id = Column(BigInteger, ForeignKey("messages.id"), nullable=True)
+    is_public = Column(Boolean, default=False)
+
+    # Relationships
+    sender = relationship("User", back_populates="messages")
+    recipients = relationship("MessageRecipient", back_populates="message", cascade="all, delete-orphan")
+    reply_to = relationship("Message", remote_side=[id], foreign_keys=[reply_to_id])
+    thread = relationship("Message", remote_side=[id], foreign_keys=[thread_id])
+    reactions = relationship("MessageReaction", back_populates="message", cascade="all, delete-orphan")
+
+class MessageRecipient(Base):
+    __tablename__ = "message_recipients"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    message_id = Column(BigInteger, ForeignKey("messages.id"), nullable=False, index=True)
+    recipient_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, index=True)
+    read_at = Column(DateTime, nullable=True)
+    delivered_at = Column(DateTime, nullable=True)
+    encrypted_key = Column(Text, nullable=True)
+
+    # Relationships
+    message = relationship("Message", back_populates="recipients")
+    recipient = relationship("User", back_populates="message_recipients")
+
+class MessageReaction(Base):
+    __tablename__ = "message_reactions"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    message_id = Column(BigInteger, ForeignKey("messages.id"), nullable=False, index=True)
+    user_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, index=True)
+    reaction = Column(String(50), nullable=False)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+    # Relationships
+    message = relationship("Message", back_populates="reactions")
+
+class Device(Base):
+    __tablename__ = "devices"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    user_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, index=True)
+    device_id = Column(String(255), unique=True, nullable=False, index=True)
+    device_name = Column(String(255), nullable=True)
+    device_type = Column(String(50), nullable=True)
+    public_key = Column(Text, nullable=True)
+    signed_prekey = Column(Text, nullable=True)
+    one_time_prekeys = Column(JSON, nullable=True)
+    last_active = Column(DateTime, default=datetime.utcnow)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+    # Relationships
+    user = relationship("User", back_populates="devices")
+    push_subscriptions = relationship("PushSubscription", back_populates="device", cascade="all, delete-orphan")
+
+class PushSubscription(Base):
+    __tablename__ = "push_subscriptions"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    user_id = Column(BigInteger, ForeignKey("users.id"), nullable=False, index=True)
+    device_id = Column(BigInteger, ForeignKey("devices.id"), nullable=True, index=True)
+    endpoint = Column(String(500), nullable=False)
+    p256dh = Column(String(255), nullable=False)
+    auth = Column(String(255), nullable=False)
+    user_agent = Column(String(500), nullable=True)
+    created_at = Column(DateTime, default=datetime.utcnow)
+
+    # Relationships
+    user = relationship("User", back_populates="push_subscriptions")
+    device = relationship("Device", back_populates="push_subscriptions")
+
+class WebRTCSession(Base):
+    __tablename__ = "webrtc_sessions"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    session_id = Column(String(255), unique=True, nullable=False, index=True)
+    initiator_id = Column(BigInteger, ForeignKey("users.id"), nullable=False)
+    participant_ids = Column(JSON, nullable=False)
+    offer = Column(JSON, nullable=True)
+    answer = Column(JSON, nullable=True)
+    ice_candidates = Column(JSON, nullable=True)
+    status = Column(String(50), default="pending")
+    created_at = Column(DateTime, default=datetime.utcnow)
+    updated_at = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
+
+class ModerationAction(Base):
+    __tablename__ = "moderation_actions"
+
+    id = Column(BigInteger, primary_key=True, index=True)
+    moderator_id = Column(BigInteger, ForeignKey("users.id"), nullable=False)
+    target_user_id = Column(BigInteger, ForeignKey("users.id"), nullable=True)
+    target_message_id = Column(BigInteger, ForeignKey("messages.id"), nullable=True)
+    action_type = Column(String(50), nullable=False)
+    reason = Column(Text, nullable=True)
+    created_at = Column(DateTime, default=datetime.utcnow)
+    expires_at = Column(DateTime, nullable=True)
+
+
+class MessageFile(Base):
+    __tablename__ = "message_file"
+
+    id = Column(Integer, primary_key=True, index=True)
+    message_id = Column(Integer, ForeignKey("message.id"), nullable=False, index=True)
+    path = Column(Text, nullable=False)
+    name = Column(Text, nullable=False)
+
+    message = relationship("Message", back_populates="files")
+
+
+class CryptoPublicKey(Base):
+    __tablename__ = "crypto_public_key"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False, unique=True)
+    public_key_b64 = Column(Text, nullable=False)
+
+
+class CryptoBackup(Base):
+    __tablename__ = "crypto_backup"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False, unique=True)
+    blob_json = Column(Text, nullable=False)
+
+
+class DMEnvelope(Base):
+    __tablename__ = "dm_envelope"
+
+    id = Column(Integer, primary_key=True, index=True)
+    sender_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    recipient_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    iv_b64 = Column(Text, nullable=False)
+    ciphertext_b64 = Column(Text, nullable=False)
+    salt_b64 = Column(Text, nullable=False)
+    iv2_b64 = Column(Text, nullable=False)
+    wrapped_mk_b64 = Column(Text, nullable=False)
+    reply_to_id = Column(Integer, nullable=True)
+    timestamp = Column(DateTime, default=datetime.now)
+    files = relationship("DMFile", back_populates="message", cascade="all, delete-orphan", lazy="select")
+    reactions = relationship("DMReaction", cascade="all, delete-orphan", lazy="select")
+
+
+class DMFile(Base):
+    __tablename__ = "dm_file"
+
+    id = Column(Integer, primary_key=True, index=True)
+    message_id = Column(Integer, ForeignKey("dm_envelope.id"), nullable=False, index=True)
+    sender_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    recipient_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    name = Column(Text, nullable=False)
+    path = Column(Text, nullable=False)
+
+    message = relationship("DMEnvelope", back_populates="files")
+
+
+class FcmToken(Base):
+    __tablename__ = "fcm_token"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False, index=True)
+    token = Column(Text, nullable=False, unique=True)
+    created_at = Column(DateTime, default=datetime.now)
+    updated_at = Column(DateTime, default=datetime.now, onupdate=datetime.now)
+
+
+class Reaction(Base):
+    __tablename__ = "reaction"
+
+    id = Column(Integer, primary_key=True, index=True)
+    message_id = Column(Integer, ForeignKey("message.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    emoji = Column(String(10), nullable=False)  # Store emoji as string
+    timestamp = Column(DateTime, default=datetime.now)
+
+    # Relationships
+    user = relationship("User")
+
+    # Ensure unique combination of message, user, and emoji
+    __table_args__ = (UniqueConstraint('message_id', 'user_id', 'emoji', name='unique_reaction'),)
+
+
+class DMReaction(Base):
+    __tablename__ = "dm_reaction"
+
+    id = Column(Integer, primary_key=True, index=True)
+    dm_envelope_id = Column(Integer, ForeignKey("dm_envelope.id"), nullable=False, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False)
+    emoji = Column(String(10), nullable=False)  # Store emoji as string
+    timestamp = Column(DateTime, default=datetime.now)
+
+    # Relationships
+    user = relationship("User")
+    dm_envelope = relationship("DMEnvelope", overlaps="reactions")
+
+    # Ensure unique combination of dm_envelope, user, and emoji
+    __table_args__ = (UniqueConstraint('dm_envelope_id', 'user_id', 'emoji', name='unique_dm_reaction'),)
+
+
+# Tracks authenticated device sessions per user
+class DeviceSession(Base):
+    __tablename__ = "device_session"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False, index=True)
+
+    # Raw User-Agent for reference/debugging
+    raw_user_agent = Column(Text, nullable=True)
+
+    # Parsed fields
+    device_name = Column(String(128), nullable=True)
+    device_type = Column(String(32), nullable=True)  # desktop/mobile/tablet/bot/unknown
+    os_name = Column(String(64), nullable=True)
+    os_version = Column(String(64), nullable=True)
+    browser_name = Column(String(64), nullable=True)
+    browser_version = Column(String(64), nullable=True)
+    brand = Column(String(64), nullable=True)
+    model = Column(String(64), nullable=True)
+
+    # Session identity embedded into JWTs
+    session_id = Column(String(64), unique=True, nullable=False, index=True)
+
+    # Lifecycle
+    created_at = Column(DateTime, default=datetime.now)
+    last_seen = Column(DateTime, default=datetime.now)
+    revoked = Column(Boolean, default=False)
+
+    # Relationship back to user (optional lazy to avoid heavy loads)
+    user = relationship("User", lazy="select")
+
+
+# Pydantic models
+class LoginRequest(BaseModel):
+    username: str
+    password: str
+
+
+class RegisterRequest(BaseModel):
+    username: str
+    display_name: str
+    password: str
+    confirm_password: str
+
+
+class ChangePasswordRequest(BaseModel):
+    currentPasswordDerived: str
+    newPasswordDerived: str
+    logoutAllExceptCurrent: bool = False
+
+
+class SendMessageRequest(BaseModel):
+    content: str
+    reply_to_id: int | None = None
+
+
+class EditMessageRequest(BaseModel):
+    content: str
+
+
+class DeleteMessageRequest(BaseModel):
+    message_id: int
+
+
+class UpdateBioRequest(BaseModel):
+    bio: str
+
+
+class PushSubscriptionRequest(BaseModel):
+    endpoint: str
+    keys: dict
+
+
+class UserProfileResponse(BaseModel):
+    id: int
+    username: str
+    display_name: str
+    profile_picture: str | None
+    bio: str | None
+    online: bool
+    last_seen: datetime | None
+    created_at: datetime | None
+    verified: bool
+    suspended: bool
+    suspension_reason: str | None
+    deleted: bool
+
+    class Config:
+        from_attributes = True
+
+
+class MessageResponse(BaseModel):
+    id: int
+    content: str
+    timestamp: datetime
+    is_author: bool
+    is_read: bool
+    username: str
+    profile_picture: str | None
+
+    class Config:
+        from_attributes = True
+
+
+class ReactionRequest(BaseModel):
+    message_id: int
+    emoji: str
+
+
+class ReactionResponse(BaseModel):
+    id: int
+    message_id: int
+    user_id: int
+    emoji: str
+    timestamp: datetime
+    username: str
+
+    class Config:
+        from_attributes = True
+
+
+class DMReactionRequest(BaseModel):
+    dm_envelope_id: int
+    emoji: str
+
+
+class DMReactionResponse(BaseModel):
+    id: int
+    dm_envelope_id: int
+    user_id: int
+    emoji: str
+    timestamp: datetime
+    username: str
+
+    class Config:
+        from_attributes = True
+
+
+class UpdateLog(Base):
+    """Stores update sequence numbers and updates for gap detection"""
+    __tablename__ = "update_log"
+
+    id = Column(Integer, primary_key=True, index=True)
+    user_id = Column(Integer, ForeignKey("user.id"), nullable=False, index=True)
+    sequence = Column(Integer, nullable=False, index=True)
+    updates = Column(Text, nullable=False)  # JSON array of updates
+    timestamp = Column(DateTime, default=datetime.now, index=True)
+
+    __table_args__ = (
+        UniqueConstraint("user_id", "sequence", name="uq_user_sequence"),
+    )

backend/shared/utils.py

@@ -0,0 +1,234 @@
+import secrets
+import string
+import hashlib
+import hmac
+import base64
+import json
+from datetime import datetime, timedelta
+from typing import Optional
+import re
+from cryptography.hazmat.primitives import hashes
+from cryptography.hazmat.primitives.kdf.pbkdf2 import PBKDF2HMAC
+from cryptography.hazmat.backends import default_backend
+import nacl.secret
+import nacl.utils
+from fastapi import Request
+import jwt
+import bcrypt
+from backend.shared.constants import JWT_SECRET_KEY, JWT_ALGORITHM, MAX_TOKEN_LIFETIME_HOURS
+import ipaddress
+
+def generate_secure_token(length: int = 32) -> str:
+    """Generate a cryptographically secure random token."""
+    alphabet = string.ascii_letters + string.digits
+    return ''.join(secrets.choice(alphabet) for _ in range(length))
+
+def hash_password(password: str, salt: Optional[bytes] = None) -> tuple[str, bytes]:
+    """Hash a password with PBKDF2 and return (hash, salt)."""
+    if salt is None:
+        salt = secrets.token_bytes(32)
+
+    kdf = PBKDF2HMAC(
+        algorithm=hashes.SHA256(),
+        length=32,
+        salt=salt,
+        iterations=100000,
+        backend=default_backend()
+    )
+
+    key = kdf.derive(password.encode())
+    return base64.b64encode(key).decode(), salt
+
+def verify_password(password: str, hashed: str, salt: bytes) -> bool:
+    """Verify a password against its hash and salt."""
+    try:
+        key = base64.b64decode(hashed)
+        kdf = PBKDF2HMAC(
+            algorithm=hashes.SHA256(),
+            length=32,
+            salt=salt,
+            iterations=100000,
+            backend=default_backend()
+        )
+        kdf.verify(password.encode(), key)
+        return True
+    except:
+        return False
+
+def generate_verification_token() -> str:
+    """Generate a verification token for email verification."""
+    return generate_secure_token(64)
+
+def generate_reset_token() -> str:
+    """Generate a password reset token."""
+    return generate_secure_token(64)
+
+def get_client_ip(request: Request) -> str:
+    """Extract the real client IP from the request."""
+    # Check X-Forwarded-For header first
+    forwarded_for = request.headers.get("X-Forwarded-For")
+    if forwarded_for:
+        # Take the first IP in case of multiple proxies
+        client_ip = forwarded_for.split(",")[0].strip()
+        try:
+            # Validate IP address
+            ipaddress.ip_address(client_ip)
+            return client_ip
+        except ValueError:
+            pass
+
+    # Check X-Real-IP header
+    real_ip = request.headers.get("X-Real-IP")
+    if real_ip:
+        try:
+            ipaddress.ip_address(real_ip)
+            return real_ip
+        except ValueError:
+            pass
+
+    # Fallback to request.client.host
+    client_host = request.client.host if request.client else "unknown"
+    try:
+        ipaddress.ip_address(client_host)
+        return client_host
+    except ValueError:
+        return "unknown"
+
+def validate_email(email: str) -> bool:
+    """Validate email address format."""
+    pattern = r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$'
+    return re.match(pattern, email) is not None
+
+def validate_username(username: str) -> bool:
+    """Validate username format."""
+    if not username or len(username) < 3 or len(username) > 50:
+        return False
+
+    # Allow alphanumeric, underscore, and hyphen
+    pattern = r'^[a-zA-Z0-9_-]+$'
+    return re.match(pattern, username) is not None
+
+def sanitize_filename(filename: str) -> str:
+    """Sanitize filename to prevent directory traversal."""
+    return re.sub(r'[^\w\.-]', '_', filename)
+
+def generate_file_hash(content: bytes) -> str:
+    """Generate SHA256 hash of file content."""
+    return hashlib.sha256(content).hexdigest()
+
+def encrypt_data(data: str, key: bytes) -> str:
+    """Encrypt data using NaCl secret box."""
+    box = nacl.secret.SecretBox(key)
+    encrypted = box.encrypt(data.encode())
+    return base64.b64encode(encrypted).decode()
+
+def decrypt_data(encrypted_data: str, key: bytes) -> str:
+    """Decrypt data using NaCl secret box."""
+    box = nacl.secret.SecretBox(key)
+    encrypted = base64.b64decode(encrypted_data)
+    decrypted = box.decrypt(encrypted)
+    return decrypted.decode()
+
+def generate_encryption_key() -> bytes:
+    """Generate a new encryption key."""
+    return nacl.utils.random(nacl.secret.SecretBox.KEY_SIZE)
+
+def format_datetime(dt: datetime) -> str:
+    """Format datetime for API responses."""
+    return dt.isoformat()
+
+def parse_datetime(dt_str: str) -> Optional[datetime]:
+    """Parse datetime from API requests."""
+    try:
+        return datetime.fromisoformat(dt_str.replace('Z', '+00:00'))
+    except:
+        return None
+
+def calculate_age(birth_date: datetime) -> int:
+    """Calculate age from birth date."""
+    today = datetime.now()
+    age = today.year - birth_date.year
+    if today.month < birth_date.month or (today.month == birth_date.month and today.day < birth_date.day):
+        age -= 1
+    return age
+
+def truncate_text(text: str, max_length: int, suffix: str = "...") -> str:
+    """Truncate text to max length with suffix."""
+    if len(text) <= max_length:
+        return text
+    return text[:max_length - len(suffix)] + suffix
+
+def is_valid_url(url: str) -> bool:
+    """Validate URL format."""
+    pattern = r'^https?://[^\s/$.?#].[^\s]*$'
+    return re.match(pattern, url) is not None
+
+def generate_device_id() -> str:
+    """Generate a unique device identifier."""
+    return generate_secure_token(32)
+
+def normalize_phone_number(phone: str) -> str:
+    """Normalize phone number format."""
+    # Remove all non-digit characters except +
+    normalized = re.sub(r'[^\d+]', '', phone)
+
+    # Ensure it starts with +
+    if not normalized.startswith('+'):
+        if normalized.startswith('00'):
+            normalized = '+' + normalized[2:]
+        else:
+            normalized = '+' + normalized
+
+    return normalized
+
+
+def create_token(user_id: int, username: str, session_id: str) -> str:
+    # Set a long expiration as safety net (actual expiration based on inactivity)
+    expire = datetime.now() + timedelta(hours=MAX_TOKEN_LIFETIME_HOURS)
+    payload = {
+        "user_id": user_id,
+        "username": username,
+        "session_id": session_id,
+        "exp": int(expire.timestamp())  # JWT exp must be Unix timestamp (int)
+    }
+    return jwt.encode(payload, JWT_SECRET_KEY, algorithm=JWT_ALGORITHM)
+
+
+def get_password_hash(password: str) -> str:
+    return bcrypt.hashpw(password.encode("utf-8"), bcrypt.gensalt()).decode("utf-8")
+
+
+def verify_password(plain_password: str, hashed_password: str) -> bool:
+    return bcrypt.checkpw(plain_password.encode("utf-8"), hashed_password.encode("utf-8"))
+
+
+def verify_token(token: str) -> Optional[dict]:
+    try:
+        payload = jwt.decode(token, JWT_SECRET_KEY, algorithms=[JWT_ALGORITHM])
+        return payload
+    except jwt.ExpiredSignatureError:
+        return None
+    except jwt.InvalidTokenError:
+        return None
+
+
+def _is_admin(user) -> bool:
+    return user.id == 1
+
+
+def convert_user(user) -> dict:
+    return {
+        "id": user.id,
+        "created_at": user.created_at.isoformat(),
+        "last_seen": user.last_seen.isoformat(),
+        "online": user.online,
+        "username": user.username,
+        "display_name": user.display_name,
+        "profile_picture": user.profile_picture,
+        "bio": user.bio,
+        "admin": _is_admin(user),
+        "verified": user.verified,
+        "suspended": user.suspended or False,
+        "suspension_reason": user.suspension_reason,
+        "deleted": (user.deleted or user.suspended) or False  # Treat suspended as deleted
+    }

backend/shared/validation.py

@@ -0,0 +1,132 @@
+from typing import Optional
+from pydantic import BaseModel, EmailStr, Field, validator
+import re
+
+
+def is_valid_username(username: str) -> bool:
+    if len(username) < 3 or len(username) > 20:
+        return False
+    # Only allow English letters, numbers, dashes and underscores
+    if not re.match(r'^[a-zA-Z0-9_-]+$', username):
+        return False
+    return True
+
+
+def is_valid_display_name(display_name: str) -> bool:
+    if len(display_name) < 1 or len(display_name) > 64:
+        return False
+    # Check if not blank (only whitespace)
+    if not display_name.strip():
+        return False
+    return True
+
+
+def is_valid_password(password: str) -> bool:
+    if len(password) < 5 or len(password) > 50:
+        return False
+    if re.search(r'[\s\u180E\u200B-\u200D\u2060\uFEFF]', password):
+        return False
+    return True
+
+class UserCreate(BaseModel):
+    username: str = Field(min_length=3, max_length=50)
+    email: EmailStr
+    password: str = Field(min_length=8, max_length=128)
+    display_name: Optional[str] = Field(None, max_length=100)
+
+    @validator('username')
+    def username_alphanumeric(cls, v):
+        if not re.match(r'^[a-zA-Z0-9_-]+$', v):
+            raise ValueError('Username must be alphanumeric with underscores or hyphens')
+        return v
+
+    @validator('password')
+    def password_strength(cls, v):
+        if not re.search(r'[A-Z]', v):
+            raise ValueError('Password must contain at least one uppercase letter')
+        if not re.search(r'[a-z]', v):
+            raise ValueError('Password must contain at least one lowercase letter')
+        if not re.search(r'\d', v):
+            raise ValueError('Password must contain at least one digit')
+        return v
+
+class UserLogin(BaseModel):
+    username_or_email: str = Field(min_length=1, max_length=100)
+    password: str = Field(min_length=1, max_length=128)
+
+class UserUpdate(BaseModel):
+    display_name: Optional[str] = Field(None, max_length=100)
+    bio: Optional[str] = Field(None, max_length=500)
+    avatar_url: Optional[str] = Field(None, max_length=255)
+
+    @validator('avatar_url')
+    def validate_avatar_url(cls, v):
+        if v and not v.startswith(('http://', 'https://')):
+            raise ValueError('Avatar URL must be a valid HTTP/HTTPS URL')
+        return v
+
+class MessageCreate(BaseModel):
+    content: str = Field(min_length=1, max_length=10000)
+    content_type: str = Field(default="text", pattern=r'^(text|image|video|audio|file)$')
+    reply_to_id: Optional[int] = None
+    recipient_ids: list[int] = Field(min_items=1, max_items=100)
+
+class MessageUpdate(BaseModel):
+    content: str = Field(min_length=1, max_length=10000)
+
+class DeviceRegister(BaseModel):
+    device_id: str = Field(min_length=1, max_length=255)
+    device_name: Optional[str] = Field(None, max_length=255)
+    device_type: Optional[str] = Field(None, max_length=50)
+    public_key: Optional[str] = Field(None, max_length=10000)
+
+class PushSubscriptionCreate(BaseModel):
+    endpoint: str = Field(max_length=500)
+    p256dh: str = Field(max_length=255)
+    auth: str = Field(max_length=255)
+    device_id: Optional[str] = Field(None, max_length=255)
+
+class WebRTCOffer(BaseModel):
+    offer: dict
+    participant_ids: list[int] = Field(min_items=1, max_items=10)
+
+class WebRTCAnswer(BaseModel):
+    answer: dict
+    session_id: str = Field(max_length=255)
+
+class WebRTCIceCandidate(BaseModel):
+    candidate: dict
+    session_id: str = Field(max_length=255)
+
+class ModerationActionCreate(BaseModel):
+    target_user_id: Optional[int] = None
+    target_message_id: Optional[int] = None
+    action_type: str = Field(pattern=r'^(ban|mute|delete|warn)$')
+    reason: Optional[str] = Field(None, max_length=1000)
+    duration_hours: Optional[int] = Field(None, gt=0, le=8760)  # Max 1 year
+
+class PasswordResetRequest(BaseModel):
+    email: EmailStr
+
+class PasswordReset(BaseModel):
+    token: str = Field(min_length=64, max_length=64)
+    new_password: str = Field(..., min_length=8, max_length=128)
+
+    @validator('new_password')
+    def password_strength(cls, v):
+        if not re.search(r'[A-Z]', v):
+            raise ValueError('Password must contain at least one uppercase letter')
+        if not re.search(r'[a-z]', v):
+            raise ValueError('Password must contain at least one lowercase letter')
+        if not re.search(r'\d', v):
+            raise ValueError('Password must contain at least one digit')
+        return v
+
+class TwoFactorSetup(BaseModel):
+    code: str = Field(pattern=r'^\d{6}$')
+
+class TwoFactorVerify(BaseModel):
+    code: str = Field(pattern=r'^\d{6}$')
+
+class EmailVerification(BaseModel):
+    token: str = Field(min_length=64, max_length=64)