prevent data in database and added migration from old databasename lexoffice

app/database.py

@@ -1,8 +1,12 @@
+import logging
 import os
 import aiosqlite
 from cryptography.fernet import Fernet
 
 DB_PATH = os.environ.get("DB_PATH", "/data/belegimport.db")
+SCHEMA_VERSION = 2
+
+logger = logging.getLogger(__name__)
 
 _fernet = None
 
@@ -78,9 +82,86 @@ def _decrypt(fernet: Fernet, value: str) -> str:
         return ""
 
 
+async def _get_schema_version(db: aiosqlite.Connection) -> int:
+    """Read current schema version from DB. Returns 0 if not set."""
+    try:
+        cursor = await db.execute(
+            "SELECT value FROM settings WHERE key = 'schema_version'"
+        )
+        row = await cursor.fetchone()
+        return int(row[0]) if row else 0
+    except Exception:
+        return 0
+
+
+async def _set_schema_version(db: aiosqlite.Connection, version: int):
+    await db.execute(
+        "INSERT OR REPLACE INTO settings (key, value) VALUES ('schema_version', ?)",
+        (str(version),),
+    )
+
+
+async def _run_migrations(db: aiosqlite.Connection, current_version: int):
+    """Run all pending migrations sequentially."""
+
+    if current_version < 1:
+        logger.info("Migration v1: Initiale Tabellenstruktur")
+        # v1: Base tables (idempotent via IF NOT EXISTS)
+        await db.execute("""
+            CREATE TABLE IF NOT EXISTS settings (
+                key TEXT PRIMARY KEY,
+                value TEXT NOT NULL DEFAULT ''
+            )
+        """)
+        await db.execute("""
+            CREATE TABLE IF NOT EXISTS processing_log (
+                id INTEGER PRIMARY KEY AUTOINCREMENT,
+                timestamp TEXT NOT NULL DEFAULT (datetime('now', 'localtime')),
+                email_subject TEXT,
+                email_from TEXT,
+                attachments_count INTEGER DEFAULT 0,
+                status TEXT NOT NULL,
+                error_message TEXT
+            )
+        """)
+        await db.commit()
+        await _set_schema_version(db, 1)
+
+    if current_version < 2:
+        logger.info("Migration v2: lexoffice_email -> import_email")
+        # v2: Rename lexoffice_email -> import_email
+        cursor = await db.execute(
+            "SELECT value FROM settings WHERE key = 'lexoffice_email'"
+        )
+        row = await cursor.fetchone()
+        if row and row[0]:
+            # Copy value to import_email if it's empty
+            cursor2 = await db.execute(
+                "SELECT value FROM settings WHERE key = 'import_email'"
+            )
+            row2 = await cursor2.fetchone()
+            if not row2 or not row2[0]:
+                await db.execute(
+                    "INSERT OR REPLACE INTO settings (key, value) VALUES ('import_email', ?)",
+                    (row[0],),
+                )
+                logger.info("  lexoffice_email Wert nach import_email übertragen")
+            await db.execute("DELETE FROM settings WHERE key = 'lexoffice_email'")
+        await db.commit()
+        await _set_schema_version(db, 2)
+
+    # --- Future migrations go here ---
+    # if current_version < 3:
+    #     logger.info("Migration v3: ...")
+    #     await _set_schema_version(db, 3)
+
+    await db.commit()
+
+
 async def init_db():
-    os.makedirs(os.path.dirname(DB_PATH), exist_ok=True)
+    os.makedirs(os.path.dirname(DB_PATH) or ".", exist_ok=True)
     async with aiosqlite.connect(DB_PATH) as db:
+        # Ensure base tables exist (needed before we can read schema_version)
         await db.execute("""
             CREATE TABLE IF NOT EXISTS settings (
                 key TEXT PRIMARY KEY,
@@ -100,7 +181,18 @@ async def init_db():
         """)
         await db.commit()
 
-        # Insert default settings if not present
+        # Check version and run migrations
+        current_version = await _get_schema_version(db)
+        if current_version < SCHEMA_VERSION:
+            logger.info(
+                f"DB-Schema v{current_version} -> v{SCHEMA_VERSION}, starte Migrationen..."
+            )
+            await _run_migrations(db, current_version)
+            logger.info(f"DB-Schema auf v{SCHEMA_VERSION} aktualisiert")
+        else:
+            logger.info(f"DB-Schema v{current_version} ist aktuell")
+
+        # Insert default settings for any new keys (never overwrites existing values)
         for key, value in DEFAULT_SETTINGS.items():
             await db.execute(
                 "INSERT OR IGNORE INTO settings (key, value) VALUES (?, ?)",
@@ -116,7 +208,7 @@ async def get_settings() -> dict:
     fernet = await _get_fernet()
     async with aiosqlite.connect(DB_PATH) as db:
         cursor = await db.execute(
-            "SELECT key, value FROM settings WHERE key != 'encryption_key'"
+            "SELECT key, value FROM settings WHERE key NOT IN ('encryption_key', 'schema_version')"
         )
         rows = await cursor.fetchall()
 
@@ -133,7 +225,7 @@ async def save_settings(data: dict):
     fernet = await _get_fernet()
     async with aiosqlite.connect(DB_PATH) as db:
         for key, value in data.items():
-            if key == "encryption_key":
+            if key in ("encryption_key", "schema_version"):
                 continue
             store_value = _encrypt(fernet, value) if key in ENCRYPTED_KEYS else value
             await db.execute(