feat: expose workflow capabilities over json rpc

tests/wf_transport_rpc_http/test_app.py

@@ -0,0 +1,60 @@
+from __future__ import annotations
+
+import asyncio
+from typing import Any
+
+import httpx
+
+from wf_server import build_local_static_workflow_server
+from wf_transport_rpc_http.app import create_rpc_app
+
+
+async def _rpc(client: httpx.AsyncClient, method: str, params: dict[str, Any]) -> dict[str, Any]:
+    response = await client.post(
+        "/rpc",
+        json={"jsonrpc": "2.0", "id": "test", "method": method, "params": params},
+    )
+    assert response.status_code == 200
+    return response.json()
+
+
+def test_rpc_health_and_capability_methods(tmp_path) -> None:
+    async def scenario() -> None:
+        server = build_local_static_workflow_server(tmp_path / "store")
+        app = create_rpc_app(server)
+        transport = httpx.ASGITransport(app=app)
+        async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
+            health_response = await client.get("/healthz")
+            health = await _rpc(client, "workflow.health", {})
+            listed = await _rpc(
+                client,
+                "workflow.capabilities.list",
+                {"source_id": "wf.std", "limit": 10},
+            )
+            inspected = await _rpc(
+                client,
+                "workflow.capabilities.inspect",
+                {"qualified_name": "wf.std.constant"},
+            )
+
+        assert health_response.status_code == 200
+        assert health_response.json()["status"] == "ok"
+        assert health["result"]["status"] == "ok"
+        assert listed["result"]["capabilities"]
+        assert inspected["result"]["name"] == "wf.std.constant"
+
+    asyncio.run(scenario())
+
+
+def test_rpc_unknown_method_returns_json_rpc_error(tmp_path) -> None:
+    async def scenario() -> None:
+        server = build_local_static_workflow_server(tmp_path / "store")
+        app = create_rpc_app(server)
+        transport = httpx.ASGITransport(app=app)
+        async with httpx.AsyncClient(transport=transport, base_url="http://test") as client:
+            payload = await _rpc(client, "workflow.nope", {})
+
+        assert payload["error"]["code"] == -32601
+        assert payload["error"]["message"] == "Method not found"
+
+    asyncio.run(scenario())