add listener routes for internal service proxying (#793)

cli/planoai/config_generator.py

@@ -145,6 +145,41 @@ def validate_and_render_schema():
                 inferred_clusters[name]["port"],
             ) = get_endpoint_and_port(endpoint, protocol)
 
+    # Process routes in listeners and generate clusters for upstream services
+    for listener in listeners:
+        for route in listener.get("routes", []):
+            path_prefix = route.get("path_prefix", "")
+            upstream = route.get("upstream", "")
+            if not path_prefix or not upstream:
+                continue
+
+            urlparse_result = urlparse(upstream)
+            if not urlparse_result.scheme or not urlparse_result.hostname:
+                raise Exception(
+                    f"Invalid upstream URL '{upstream}' in route for listener '{listener.get('name')}'. "
+                    f"Must be a valid URL with scheme (http/https) and hostname."
+                )
+
+            protocol = urlparse_result.scheme
+            port = urlparse_result.port
+            if port is None:
+                port = 80 if protocol == "http" else 443
+
+            sanitized_prefix = (
+                path_prefix.strip("/").replace("/", "_").replace("-", "_")
+            )
+            listener_name = listener.get("name", "unknown").replace(" ", "_")
+            cluster_name = f"route_{listener_name}_{sanitized_prefix}"
+
+            route["cluster_name"] = cluster_name
+
+            if cluster_name not in inferred_clusters:
+                inferred_clusters[cluster_name] = {
+                    "endpoint": urlparse_result.hostname,
+                    "port": port,
+                    "protocol": protocol,
+                }
+
     print("defined clusters from plano_config.yaml: ", json.dumps(inferred_clusters))
 
     if "prompt_targets" in config_yaml:

cli/test/test_config_generator.py

@@ -289,6 +289,63 @@ llm_providers:
 tracing:
   random_sampling: 100
 
+""",
+    },
+    {
+        "id": "routes_with_agents",
+        "expected_error": None,
+        "plano_config": """
+version: v0.3.0
+
+agents:
+  - id: test_agent
+    url: http://localhost:10500
+
+listeners:
+  - type: agent
+    name: agent_1
+    port: 8001
+    routes:
+      - path_prefix: /traces
+        upstream: http://localhost:16686
+    agents:
+      - id: test_agent
+        description: a test agent
+
+  - type: model
+    name: model_listener
+    port: 12000
+
+model_providers:
+  - model: openai/gpt-4o
+    access_key: $OPENAI_API_KEY
+
+""",
+    },
+    {
+        "id": "routes_only_listener",
+        "expected_error": None,
+        "plano_config": """
+version: v0.3.0
+
+listeners:
+  - type: agent
+    name: observability
+    port: 8002
+    routes:
+      - path_prefix: /traces
+        upstream: http://localhost:16686
+      - path_prefix: /metrics
+        upstream: http://localhost:9090
+
+  - type: model
+    name: model_listener
+    port: 12000
+
+model_providers:
+  - model: openai/gpt-4o
+    access_key: $OPENAI_API_KEY
+
 """,
     },
 ]