Stage 326: PR #1953 — fix(config): skip #1776 provider peel for custom host:port slugs by @lucky-yonug

api/config.py

@@ -1430,6 +1430,44 @@ def _base_url_points_at_local_server(base_url: str) -> bool:
         return False
 
 
+def _custom_slug_rest_looks_like_host_port(rest: str) -> bool:
+    """True when ``custom:<rest>`` is an endpoint-style slug ``host:port``.
+
+    WebUI sometimes derives ``custom:10.8.71.41:8080`` from ``base_url`` authority.
+    The #1776 peel must not treat that middle colon as part of an eaten model
+    segment — otherwise ``@custom:10.8.71.41:8080:Qwen3`` wrongly becomes model
+    ``8080:Qwen3``.
+    """
+    rest = str(rest or "").strip()
+    if ":" not in rest:
+        return False
+    host, port_s = rest.rsplit(":", 1)
+    if not host or ":" in host:
+        return False
+    if not port_s.isdigit():
+        return False
+    try:
+        port_n = int(port_s)
+    except ValueError:
+        return False
+    if not (1 <= port_n <= 65535):
+        return False
+    try:
+        import ipaddress
+
+        ipaddress.ip_address(host)
+        return True
+    except ValueError:
+        pass
+    hl = host.lower()
+    if hl == "localhost":
+        return True
+    # Typical DNS hostname used as proxy slug (contains at least one label dot).
+    if "." in host:
+        return True
+    return False
+
+
 def resolve_model_provider(model_id: str) -> tuple:
     """Resolve model name, provider, and base_url for AIAgent.
 
@@ -1516,15 +1554,20 @@ def resolve_model_provider(model_id: str) -> tuple:
     # ("@custom:my-key:some-model:free"), rsplit yields
     # provider_hint="custom:my-key:some-model", bare_model="free", and the
     # custom-prefix guard below skips the split-fallback. Detect the
-    # over-split structurally — custom hints carry exactly one segment after
-    # "custom:", so any provider_hint with 2+ colons that starts with
-    # "custom:" has eaten part of the model name. Peel one segment back.
+    # over-split structurally — custom hints normally carry one slug segment
+    # after ``custom:``. If ``provider_hint`` has extra ``:`` tokens because the
+    # model ID contained tags like ``:free``, peel one segment back (#1776).
+    #
+    # Exception: ``custom:<ip-or-host>:<port>`` is a single logical slug derived
+    # from OpenAI ``base_url`` authority and contains no eaten model segments.
     if model_id.startswith("@") and ":" in model_id:
         inner = model_id[1:]
         provider_hint, bare_model = inner.rsplit(":", 1)
         if provider_hint.startswith("custom:") and provider_hint.count(":") >= 2:
-            provider_hint, extra = provider_hint.rsplit(":", 1)
-            bare_model = f"{extra}:{bare_model}"
+            _slug_rest = provider_hint[len("custom:"):]
+            if not _custom_slug_rest_looks_like_host_port(_slug_rest):
+                provider_hint, extra = provider_hint.rsplit(":", 1)
+                bare_model = f"{extra}:{bare_model}"
         elif (provider_hint not in _PROVIDER_MODELS
                 and provider_hint not in _PROVIDER_DISPLAY
                 and not provider_hint.startswith("custom:")):

tests/test_resolve_model_provider_free_suffix.py

@@ -170,3 +170,41 @@ def test_custom_provider_slashed_model_with_free_suffix_1776():
     model, provider, _ = resolve_model_provider(qualified)
     assert provider == "custom:my-key"
     assert model == "org/model:free"
+
+
+def test_custom_provider_ipv4_port_slug_no_false_peel():
+    """host:port in custom slug must not trigger #1776 peel — avoids ``8080:model``."""
+    qualified = "@custom:10.8.71.41:8080:Qwen3-235B"
+    model, provider, _ = resolve_model_provider(qualified)
+    assert provider == "custom:10.8.71.41:8080"
+    assert model == "Qwen3-235B"
+
+
+def test_custom_provider_hostname_port_slug_no_false_peel():
+    qualified = "@custom:proxy.internal:8443:Qwen3-235B"
+    model, provider, _ = resolve_model_provider(qualified)
+    assert provider == "custom:proxy.internal:8443"
+    assert model == "Qwen3-235B"
+
+
+def test_custom_provider_localhost_port_slug_no_false_peel():
+    qualified = "@custom:localhost:11434:llama3.2"
+    model, provider, _ = resolve_model_provider(qualified)
+    assert provider == "custom:localhost:11434"
+    assert model == "llama3.2"
+
+
+def test_model_with_provider_context_custom_ipv4_port_roundtrip():
+    """Mirrors WebUI /start payload: bare model + custom:<host>:<port> provider."""
+    import api.config as cfg_mod
+
+    old = dict(cfg_mod.cfg.get("model", {}))
+    cfg_mod.cfg["model"] = {"provider": "custom", "default": "gpt-5.5"}
+    try:
+        wrapped = model_with_provider_context("Qwen3-235B", "custom:10.8.71.41:8080")
+        assert wrapped == "@custom:10.8.71.41:8080:Qwen3-235B"
+        model, provider, _ = resolve_model_provider(wrapped)
+        assert provider == "custom:10.8.71.41:8080"
+        assert model == "Qwen3-235B"
+    finally:
+        cfg_mod.cfg["model"] = old