logtool

logtool/source.py

@@ -0,0 +1,91 @@
+"""
+Data sources for SC-F001 logtool.
+Supports local .bin files and HTTP /log endpoint (full GET + incremental POST).
+"""
+
+import struct
+import time
+from pathlib import Path
+
+try:
+    import requests
+    _REQUESTS_OK = True
+except ImportError:
+    _REQUESTS_OK = False
+
+
+def read_file(path: str) -> bytes:
+    return Path(path).read_bytes()
+
+
+def _check_requests():
+    if not _REQUESTS_OK:
+        raise ImportError("'requests' package required for HTTP mode. Install: pip install requests")
+
+
+def fetch_full(url: str, timeout: float = 10.0) -> bytes:
+    """GET /log — returns full response blob."""
+    _check_requests()
+    resp = requests.get(url, timeout=timeout)
+    resp.raise_for_status()
+    return resp.content
+
+
+def fetch_incremental(url: str, tail: int, timeout: float = 10.0) -> tuple:
+    """
+    POST /log with tail offset.
+    Returns (raw_binary: bytes, new_head: int).
+    The raw_binary starts at the given tail and ends at new_head.
+    """
+    _check_requests()
+    resp = requests.post(url, data=str(tail), timeout=timeout)
+    resp.raise_for_status()
+    blob = resp.content
+
+    # Response is the same format: [4B json_len BE][JSON][4B tail BE][4B head BE][binary]
+    import struct as _s
+    import json as _j
+    if len(blob) < 8:
+        return b'', tail
+
+    json_len = _s.unpack_from('>I', blob, 0)[0]
+    if json_len > 65536 or len(blob) < 4 + json_len + 8:
+        return b'', tail
+
+    new_tail, new_head = _s.unpack_from('>II', blob, 4 + json_len)
+    binary = blob[4 + json_len + 8:]
+    return binary, new_head
+
+
+def stream(url: str, callback, interval_s: float = 2.0):
+    """
+    Stream new log entries from an HTTP /log endpoint.
+    - Fetches the full log on first call (GET).
+    - Polls for new entries every `interval_s` seconds (POST with last head as new tail).
+    - Calls callback(entries: list, is_first: bool) for each batch.
+    - Runs until KeyboardInterrupt.
+    """
+    from parser import autodetect_and_parse
+
+    _check_requests()
+
+    # Initial full fetch
+    blob = fetch_full(url)
+    meta, tail, head, entries = autodetect_and_parse(blob)
+    callback(entries, meta, is_first=True)
+
+    current_tail = head if head is not None else 0
+
+    # Poll for incremental updates
+    while True:
+        time.sleep(interval_s)
+        try:
+            binary, new_head = fetch_incremental(url, current_tail)
+            if binary:
+                from parser import parse_entries
+                new_entries = parse_entries(binary)
+                if new_entries:
+                    callback(new_entries, None, is_first=False)
+            current_tail = new_head
+        except Exception as exc:
+            print(f"[stream] poll error: {exc}")