feat: implement database fallback mechanism

- Add SQLite fallback support
- Enhance PostgreSQL connection checks with timeout
- Improve error handling and logging
- Add directory creation for SQLite database

docker/entrypoint.sh

@@ -3,26 +3,36 @@ set -e
 
 echo "Starting Dify services..."
 
-# Enhanced database connection check with timeout
-check_postgres() {
-    local max_attempts=30
-    local attempt=1
-    
-    while [ $attempt -le $max_attempts ]; do
-        echo "Checking PostgreSQL connection to ${DB_HOST}:${DB_PORT} (attempt $attempt/$max_attempts)..."
-        if pg_isready -h "${DB_HOST}" -p "${DB_PORT}" -U "${DB_USERNAME}" -d "${DB_DATABASE}"; then
-            return 0
-        fi
-        attempt=$((attempt + 1))
-        sleep 5
-    done
-    return 1
-}
+# Database connection check based on type
+if [ "${DATABASE_TYPE}" = "sqlite" ]; then
+    echo "Using SQLite database at ${SQLITE_PATH}"
+    # Ensure directory exists
+    mkdir -p $(dirname "${SQLITE_PATH}")
+    touch "${SQLITE_PATH}"
+else
+    # Enhanced PostgreSQL connection check with timeout
+    check_postgres() {
+        local max_attempts=30
+        local attempt=1
+        
+        while [ $attempt -le $max_attempts ]; do
+            echo "Checking PostgreSQL connection to ${DB_HOST}:${DB_PORT} (attempt $attempt/$max_attempts)..."
+            if pg_isready -h "${DB_HOST}" -p "${DB_PORT}" -U "${DB_USERNAME}" -d "${DB_DATABASE}"; then
+                return 0
+            fi
+            attempt=$((attempt + 1))
+            sleep 5
+        done
+        return 1
+    }
 
-# Try to connect with timeout
-if ! check_postgres; then
-    echo "Failed to connect to PostgreSQL after multiple attempts. Exiting."
-    exit 1
+    # Try to connect with timeout
+    if ! check_postgres; then
+        echo "Failed to connect to PostgreSQL, falling back to SQLite..."
+        export DATABASE_TYPE="sqlite"
+        mkdir -p $(dirname "${SQLITE_PATH}")
+        touch "${SQLITE_PATH}"
+    fi
 fi
 
 check_redis() {