refactor(server): adopt uv and modular typed FastAPI structure

s2s_client/core/urls.py

@@ -0,0 +1,53 @@
+from __future__ import annotations
+
+from urllib.parse import parse_qsl, urlencode, urlsplit, urlunsplit
+
+from fastapi import Request, WebSocket
+
+from s2s_client.core import config as settings
+
+
+def _url_with_query(url: str, **params: str) -> str:
+    target = urlsplit(url)
+    merged_query = dict(parse_qsl(target.query, keep_blank_values=True))
+    for key, value in params.items():
+        if value:
+            merged_query[key] = value
+    return urlunsplit(
+        (
+            target.scheme,
+            target.netloc,
+            target.path,
+            urlencode(merged_query, doseq=True),
+            target.fragment,
+        )
+    )
+
+
+def _proxy_public_url(request: Request) -> str:
+    if not settings.S2S_PROXY_TARGET:
+        return ""
+    forwarded_proto = (request.headers.get("x-forwarded-proto") or request.url.scheme).split(",")[0].strip()
+    forwarded_host = (
+        (request.headers.get("x-forwarded-host") or request.headers.get("host") or request.url.netloc)
+        .split(",")[0]
+        .strip()
+    )
+    ws_scheme = "wss" if forwarded_proto in {"https", "wss"} else "ws"
+    root_path = (request.scope.get("root_path") or "").rstrip("/")
+    return f"{ws_scheme}://{forwarded_host}{root_path}/v1/realtime"
+
+
+def _proxy_upstream_url(ws: WebSocket) -> str:
+    target = urlsplit(settings.S2S_PROXY_TARGET)
+    merged_query = dict(parse_qsl(target.query, keep_blank_values=True))
+    merged_query.update(parse_qsl(ws.url.query, keep_blank_values=True))
+    return urlunsplit(
+        (
+            target.scheme,
+            target.netloc,
+            target.path or "/v1/realtime",
+            urlencode(merged_query, doseq=True),
+            target.fragment,
+        )
+    )