Separate live HTTP media requests and background cache workers by introducing `HTTP_DOWNLOAD_SEMAPHORE` and `BACKGROUND_DOWNLOAD_SEMAPHORE`. Remove the previous global `DOWNLOAD_SEMAPHORE`, diagnostic event‑loop monitor, and related logging. Refactor `download_media_file` to handle large videos with temporary files, clean up zero‑size cache entries, and update access timestamps without semaphore tracking. Adjust background worker and request handling to use the new semaphores, simplifying concurrency control and eliminating unnecessary diagnostics.
Introduce a periodic event‑loop monitor that logs active tasks, semaphore
state, queue size and thread‑pool activity. Track the number of coroutine
waiters for the download semaphore and emit detailed diagnostic logs in
download handling and the background worker. This aids debugging of
concurrency and resource‑usage issues.
The changes ensure that when `show_caption_above` is true, text content is rendered before media, and when false, media is rendered before text. This aligns the actual rendering order with the semantic meaning of the flag, fixing a bug where content ordering did not match user expectations.
Add support for Telegram's show_caption_above_media message attribute to conditionally order caption and media content in HTML output. When enabled, media is rendered before the text caption instead of the default text-before-media order.
Logs the date range (oldest/newest) and total count of posts being added to RSS feeds, plus debug-level logging for each entry's timestamp conversion. This improves observability for feed generation and helps diagnose date-related issues.
Add flood wait exception handling in both RSS and HTML generation functions.
The bot now automatically waits for the specified duration and retries the
operation when encountering rate limiting from Telegram's API.
Add queue-based background download system to improve performance and reliability:
- Introduce DOWNLOAD_SEMAPHORE to limit concurrent downloads to 3
- Add asyncio.Queue (maxsize 100) with dedicated worker for background processing
- Implement safe_get_messages and safe_download_media wrappers with timeout protection (30s and 120s)
- Add retry logic for KeyError auth failures with 5s backoff
- Replace synchronous sequential downloads with asynchronous queued processing
- Prevent event loop blocking by queuing files instead of immediate download