Initial commit

app/state.py

@@ -0,0 +1,76 @@
+"""SQLite-backed tracking of active + historical streams.
+
+Backed by a file on the shared `appdata` PV (mounted at STATE_DB_PATH), so
+state survives pod restarts/redeploys. "Active" streams are just history
+rows with end IS NULL — no separate table needed, which also gives free
+crash recovery (if the pod dies mid-stream, the row is simply still open).
+"""
+import os
+import sqlite3
+import threading
+from datetime import datetime, timezone
+
+
+def _now_iso():
+    return datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ")
+
+
+SCHEMA = """
+CREATE TABLE IF NOT EXISTS streams (
+    id INTEGER PRIMARY KEY AUTOINCREMENT,
+    path TEXT NOT NULL,
+    source_type TEXT,
+    start TEXT NOT NULL,
+    end TEXT
+);
+CREATE INDEX IF NOT EXISTS idx_streams_active ON streams (path) WHERE end IS NULL;
+"""
+
+
+class StreamState:
+    def __init__(self, db_path, history_limit=50):
+        self._db_path = db_path
+        self._history_limit = history_limit
+        self._lock = threading.Lock()
+        os.makedirs(os.path.dirname(db_path) or ".", exist_ok=True)
+        with self._connect() as conn:
+            conn.executescript(SCHEMA)
+
+    def _connect(self):
+        conn = sqlite3.connect(self._db_path)
+        conn.row_factory = sqlite3.Row
+        return conn
+
+    def on_ready(self, path, source_type=None):
+        with self._lock, self._connect() as conn:
+            conn.execute(
+                "INSERT INTO streams (path, source_type, start, end) VALUES (?, ?, ?, NULL)",
+                (path, source_type, _now_iso()),
+            )
+
+    def on_not_ready(self, path):
+        with self._lock, self._connect() as conn:
+            row = conn.execute(
+                "SELECT id FROM streams WHERE path = ? AND end IS NULL ORDER BY id DESC LIMIT 1",
+                (path,),
+            ).fetchone()
+            if row:
+                conn.execute(
+                    "UPDATE streams SET end = ? WHERE id = ?",
+                    (_now_iso(), row["id"]),
+                )
+
+    def active(self):
+        with self._connect() as conn:
+            rows = conn.execute(
+                "SELECT path, source_type, start FROM streams WHERE end IS NULL ORDER BY id DESC"
+            ).fetchall()
+            return [dict(r) for r in rows]
+
+    def history(self):
+        with self._connect() as conn:
+            rows = conn.execute(
+                "SELECT path, source_type, start, end FROM streams ORDER BY id DESC LIMIT ?",
+                (self._history_limit,),
+            ).fetchall()
+            return [dict(r) for r in rows]