Add API key input field in sidebar - users can enter their own YouTube API key

app.py

@@ -209,12 +209,14 @@ def _fetch_chat_messages(live_chat_id: str, api_key: str, page_token: str | None
         return [], None, 5000
 
 
-def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Event, min_poll_s: float = 10.0) -> None:
+def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Event, min_poll_s: float = 10.0, api_key: str = "") -> None:
     """Background thread � scrapes live chat via YouTube Data API v3."""
-    api_key = os.getenv("YOUTUBE_API_KEY", "")
+    # Use passed key first, fall back to environment variable
+    if not api_key:
+        api_key = os.getenv("YOUTUBE_API_KEY", "")
     logger.info("YOUTUBE_API_KEY present: %s (length=%d)", bool(api_key), len(api_key))
     if not api_key:
-        msg = "YOUTUBE_API_KEY env var not set. Cannot start scraper."
+        msg = "No API key provided. Enter your YouTube Data API v3 key in the sidebar."
         logger.error(msg)
         _META["scraper_error"] = msg
         return
@@ -330,7 +332,7 @@ def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Even
     logger.info("Scraper thread ended � key=%s", redis_key)
 
 
-def start_scraper(slot_idx: int, video_id: str, redis_key: str, min_poll_s: float = 10.0) -> None:
+def start_scraper(slot_idx: int, video_id: str, redis_key: str, min_poll_s: float = 10.0, api_key: str = "") -> None:
     """Start a scraper thread for the given slot, stopping any existing one first."""
     key = str(slot_idx)
     stop_scraper(slot_idx)
@@ -338,7 +340,7 @@ def start_scraper(slot_idx: int, video_id: str, redis_key: str, min_poll_s: floa
     stop_event = threading.Event()
     t = threading.Thread(
         target=_scraper_thread_fn,
-        args=(video_id, redis_key, stop_event, min_poll_s),
+        args=(video_id, redis_key, stop_event, min_poll_s, api_key),
         daemon=True,
         name=f"scraper-{slot_idx}",
     )
@@ -969,6 +971,34 @@ with st.sidebar:
     spam_threshold   = st.slider("Spam alert threshold (%)", 10, 60, 30, key="spam_threshold_pct") / 100
     st.divider()
 
+    # -- API Key --
+    st.markdown('<p style="font-size:0.68rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:0.1em;margin-bottom:8px;">YouTube API Key</p>', unsafe_allow_html=True)
+    _env_key = os.getenv("YOUTUBE_API_KEY", "")
+    _api_key_input = st.text_input(
+        "API Key",
+        value=st.session_state.get("user_api_key", ""),
+        type="password",
+        placeholder="AIza... (paste your YouTube Data API v3 key)",
+        key="api_key_input",
+        help="Your YouTube Data API v3 key. Never shared or stored permanently.",
+    )
+    # Store in session state whenever changed
+    if _api_key_input:
+        st.session_state["user_api_key"] = _api_key_input
+    # Show status
+    _effective_key = _api_key_input or _env_key
+    if _effective_key:
+        st.markdown(
+            f'<div style="font-size:0.7rem;color:#22c55e;margin-bottom:4px;">\u2713 API key set ({len(_effective_key)} chars)</div>',
+            unsafe_allow_html=True
+        )
+    else:
+        st.markdown(
+            '<div style="font-size:0.7rem;color:#ef4444;margin-bottom:4px;">\u26a0 No API key — scraper won\'t start</div>',
+            unsafe_allow_html=True
+        )
+    st.divider()
+
     # -- Multi-Stream Scraper Control --
     st.markdown('<p style="font-size:0.68rem;font-weight:700;color:var(--accent);text-transform:uppercase;letter-spacing:0.1em;margin-bottom:8px;">Stream Control</p>', unsafe_allow_html=True)
 
@@ -997,7 +1027,7 @@ with st.sidebar:
                 vid  = extract_video_id(st.session_state[vid_skey])
                 rkey = st.session_state[rkey_skey].strip() or f"chat_messages_{label.lower()}"
                 if vid:
-                    start_scraper(idx, vid, rkey, min_poll_s=float(st.session_state.get("refresh_rate", 10)))
+                    start_scraper(idx, vid, rkey, min_poll_s=float(st.session_state.get("refresh_rate", 10)), api_key=st.session_state.get("user_api_key", "") or os.getenv("YOUTUBE_API_KEY", ""))
                     st.session_state.streams[idx]["proc"]      = _SCRAPER_THREADS.get(str(idx))
                     st.session_state.streams[idx]["video_id"]  = vid
                     st.session_state.streams[idx]["redis_key"] = rkey

shared.py

@@ -208,10 +208,11 @@ def _fetch_chat_messages(live_chat_id: str, api_key: str, page_token: str | None
         return [], None, 5000
 
 
-def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Event, min_poll_s: float = 10.0) -> None:
-    api_key = os.getenv("YOUTUBE_API_KEY", "")
+def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Event, min_poll_s: float = 10.0, api_key: str = "") -> None:
     if not api_key:
-        msg = "YOUTUBE_API_KEY env var not set. Cannot start scraper."
+        api_key = os.getenv("YOUTUBE_API_KEY", "")
+    if not api_key:
+        msg = "No API key provided. Enter your YouTube Data API v3 key in the sidebar."
         logger.error(msg)
         _META["scraper_error"] = msg
         return
@@ -296,13 +297,13 @@ def _scraper_thread_fn(video_id: str, redis_key: str, stop_event: threading.Even
         stop_event.wait(timeout=wait_s)
 
 
-def start_scraper(slot_idx: int, video_id: str, redis_key: str, min_poll_s: float = 10.0) -> None:
+def start_scraper(slot_idx: int, video_id: str, redis_key: str, min_poll_s: float = 10.0, api_key: str = "") -> None:
     key = str(slot_idx)
     stop_scraper(slot_idx)
     stop_event = threading.Event()
     t = threading.Thread(
         target=_scraper_thread_fn,
-        args=(video_id, redis_key, stop_event, min_poll_s),
+        args=(video_id, redis_key, stop_event, min_poll_s, api_key),
         daemon=True,
         name=f"scraper-{slot_idx}",
     )