fb merge phase 3

Signed-off-by: vladmandic <mandic00@live.com>

modules/api/validate.py

@@ -0,0 +1,41 @@
+import re
+import limits
+from fastapi.exceptions import HTTPException
+from modules.logger import log
+
+
+requests_summary = {}
+request_cost = {  # value is cost, 0=not rate limited, 1=default, >1 more expensive
+    "/file": 0,
+    "/run/predict": 0,
+    "/sdapi/v1/browser/thumb": 0,
+    "/sdapi/v1/network/thumb": 0,
+    "/sdapi/v1/txt2img": 5,
+    "/sdapi/v1/img2img": 5,
+    "/sdapi/v1/control": 5,
+}
+backend = limits.storage.MemoryStorage()
+strategy = limits.strategies.SlidingWindowCounterRateLimiter(backend)
+limiter = limits.parse("300/minute")
+
+
+def get_stats():
+    for k, v in requests_summary.items():
+        if v > 1:
+            log.trace(f'API stats: {k}={v}')
+
+
+def rate_limit(key):
+    cost = request_cost.get(key, 1)
+    if not strategy.hit(limiter, key, cost=cost):
+        log.warning(f'API: key={key} rate limit exceeded')
+        raise HTTPException(status_code=429, detail=f'{key}: rate limit exceeded')
+
+
+def validate_request(client, endpoint):
+    api = re.match(r"^[^?#&=]+", endpoint).group(0)
+    key = f"{client}:{api}"
+    if key not in requests_summary:
+        requests_summary[key] = 0
+    requests_summary[key] += 1
+    rate_limit(key)