fix: Make psycopg2 optional for Flask/Werkzeug compatibility

- Bump Flask requirement to >=3.0.0 (required for Werkzeug 3.x)
- Make psycopg2 import conditional in routes/adsb.py and utils/adsb_history.py
- ADS-B history features gracefully disabled when PostgreSQL libs unavailable

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

pyproject.toml

@@ -26,7 +26,7 @@ classifiers = [
     "Topic :: System :: Networking :: Monitoring",
 ]
 dependencies = [
-    "flask>=2.0.0",
+    "flask>=3.0.0",
     "skyfield>=1.45",
     "pyserial>=3.5",
     "Werkzeug>=3.1.5",

requirements.txt

@@ -1,5 +1,5 @@
 # Core dependencies
-flask>=2.0.0
+flask>=3.0.0
 flask-limiter>=2.5.4
 requests>=2.28.0
 Werkzeug>=3.1.5

routes/adsb.py

@@ -15,8 +15,16 @@ from typing import Any, Generator
 
 from flask import Blueprint, jsonify, request, Response, render_template
 from flask import make_response
-import psycopg2
+
-from psycopg2.extras import RealDictCursor
+# psycopg2 is optional - only needed for PostgreSQL history persistence
+try:
+    import psycopg2
+    from psycopg2.extras import RealDictCursor
+    PSYCOPG2_AVAILABLE = True
+except ImportError:
+    psycopg2 = None  # type: ignore
+    RealDictCursor = None  # type: ignore
+    PSYCOPG2_AVAILABLE = False
 
 import app as app_module
 from config import (
@@ -192,7 +200,7 @@ def _parse_int_param(value: str | None, default: int, min_value: int | None = No
 
 
 def _get_active_session() -> dict[str, Any] | None:
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return None
     _ensure_history_schema()
     try:
@@ -222,7 +230,7 @@ def _record_session_start(
     start_source: str | None,
     started_by: str | None,
 ) -> dict[str, Any] | None:
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return None
     _ensure_history_schema()
     try:
@@ -257,7 +265,7 @@ def _record_session_start(
 
 
 def _record_session_stop(*, stop_source: str | None, stopped_by: str | None) -> dict[str, Any] | None:
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return None
     _ensure_history_schema()
     try:
@@ -810,7 +818,8 @@ def adsb_dashboard():
 @adsb_bp.route('/history')
 def adsb_history():
     """ADS-B history reporting dashboard."""
-    resp = make_response(render_template('adsb_history.html', history_enabled=ADSB_HISTORY_ENABLED))
+    history_available = ADSB_HISTORY_ENABLED and PSYCOPG2_AVAILABLE
+    resp = make_response(render_template('adsb_history.html', history_enabled=history_available))
     resp.headers['Cache-Control'] = 'no-store'
     return resp
 
@@ -818,7 +827,7 @@ def adsb_history():
 @adsb_bp.route('/history/summary')
 def adsb_history_summary():
     """Summary stats for ADS-B history window."""
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return jsonify({'error': 'ADS-B history is disabled'}), 503
     _ensure_history_schema()
 
@@ -848,7 +857,7 @@ def adsb_history_summary():
 @adsb_bp.route('/history/aircraft')
 def adsb_history_aircraft():
     """List latest aircraft snapshots for a time window."""
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return jsonify({'error': 'ADS-B history is disabled'}), 503
     _ensure_history_schema()
 
@@ -898,7 +907,7 @@ def adsb_history_aircraft():
 @adsb_bp.route('/history/timeline')
 def adsb_history_timeline():
     """Timeline snapshots for a specific aircraft."""
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return jsonify({'error': 'ADS-B history is disabled'}), 503
     _ensure_history_schema()
 
@@ -933,7 +942,7 @@ def adsb_history_timeline():
 @adsb_bp.route('/history/messages')
 def adsb_history_messages():
     """Raw message history for a specific aircraft."""
-    if not ADSB_HISTORY_ENABLED:
+    if not ADSB_HISTORY_ENABLED or not PSYCOPG2_AVAILABLE:
         return jsonify({'error': 'ADS-B history is disabled'}), 503
     _ensure_history_schema()
 

utils/adsb_history.py

@@ -9,8 +9,16 @@ import time
 from datetime import datetime, timezone
 from typing import Iterable
 
-import psycopg2
+# psycopg2 is optional - only needed for PostgreSQL history persistence
-from psycopg2.extras import execute_values, Json
+try:
+    import psycopg2
+    from psycopg2.extras import execute_values, Json
+    PSYCOPG2_AVAILABLE = True
+except ImportError:
+    psycopg2 = None  # type: ignore
+    execute_values = None  # type: ignore
+    Json = None  # type: ignore
+    PSYCOPG2_AVAILABLE = False
 
 from config import (
     ADSB_DB_HOST,
@@ -199,7 +207,7 @@ class AdsbHistoryWriter:
     """Background writer for ADS-B history records."""
 
     def __init__(self) -> None:
-        self.enabled = ADSB_HISTORY_ENABLED
+        self.enabled = ADSB_HISTORY_ENABLED and PSYCOPG2_AVAILABLE
         self._queue: queue.Queue[dict] = queue.Queue(maxsize=ADSB_HISTORY_QUEUE_SIZE)
         self._thread: threading.Thread | None = None
         self._stop_event = threading.Event()
@@ -297,7 +305,7 @@ class AdsbSnapshotWriter:
     """Background writer for ADS-B snapshot records."""
 
     def __init__(self) -> None:
-        self.enabled = ADSB_HISTORY_ENABLED
+        self.enabled = ADSB_HISTORY_ENABLED and PSYCOPG2_AVAILABLE
         self._queue: queue.Queue[dict] = queue.Queue(maxsize=ADSB_HISTORY_QUEUE_SIZE)
         self._thread: threading.Thread | None = None
         self._stop_event = threading.Event()