feat(gnmi-test-server): add http api to inspect and reset the state

Author: felix-kaestner

Makefile

@@ -133,8 +133,8 @@ build-test-gnmi-server: FORCE
 	@$(CONTAINER_TOOL) build --tag=$(TEST_SERVER_IMG) ./test/gnmi
 
 run-test-gnmi-server: FORCE build-test-gnmi-server
-	@printf "\e[1;36m>> $(CONTAINER_TOOL) run -p 9339:9339 $(TEST_SERVER_IMG)\e[0m\n"
-	@$(CONTAINER_TOOL) run --rm -p 9339:9339 $(TEST_SERVER_IMG)
+	@printf "\e[1;36m>> $(CONTAINER_TOOL) run -p 8000:8000 -p 9339:9339 $(TEST_SERVER_IMG)\e[0m\n"
+	@$(CONTAINER_TOOL) run --rm -p 8000:8000 -p 9339:9339 $(TEST_SERVER_IMG)
 
 install-goimports: FORCE
 	@if ! hash goimports 2>/dev/null; then printf "\e[1;36m>> Installing goimports (this may take a while)...\e[0m\n"; go install golang.org/x/tools/cmd/goimports@latest; fi

Makefile.maker.yaml

@@ -172,5 +172,5 @@ verbatim: |
     @$(CONTAINER_TOOL) build --tag=$(TEST_SERVER_IMG) ./test/gnmi
 
   run-test-gnmi-server: FORCE build-test-gnmi-server
-    @printf "\e[1;36m>> $(CONTAINER_TOOL) run -p 9339:9339 $(TEST_SERVER_IMG)\e[0m\n"
-    @$(CONTAINER_TOOL) run --rm -p 9339:9339 $(TEST_SERVER_IMG)
+    @printf "\e[1;36m>> $(CONTAINER_TOOL) run -p 8000:8000 -p 9339:9339 $(TEST_SERVER_IMG)\e[0m\n"
+    @$(CONTAINER_TOOL) run --rm -p 8000:8000 -p 9339:9339 $(TEST_SERVER_IMG)

test/gnmi/Dockerfile

@@ -33,4 +33,4 @@ WORKDIR /
 COPY --from=build /usr/bin/server  /
 
 # Start the server application
-CMD ["/server", "--port=9339"]
+CMD ["/server", "--port=9339", "--http-port=8000"]

test/gnmi/README.md

@@ -74,3 +74,74 @@ Now, it's possible to connect to the server using a GNMI client such as [gnmic](
   }
 ]
 ```
+
+## HTTP API
+
+In addition to the GNMI gRPC interface, the server also provides an HTTP API for convenient state management and inspection.
+
+### HTTP Server Configuration
+
+The HTTP server runs on port 8000 by default and can be configured using the `--http-port` flag:
+
+```sh
+docker run -d -p 9339:9339 -p 8000:8000 ghcr.io/ironcore-dev/gnmi-test-server --http-port 8000
+```
+
+### Available Endpoints
+
+#### GET /v1/state
+
+Retrieves the current state of the GNMI server as JSON.
+
+**Example:**
+```sh
+# Get the current state
+curl -s http://127.0.0.1:8000/v1/state
+
+# Response when state is empty:
+{}
+
+# Response after setting some values via GNMI:
+{
+  "System": {
+    "name": "leaf1"
+  }
+}
+```
+
+#### DELETE /v1/state
+
+Clears all state from the GNMI server, resetting it to an empty state.
+
+**Example:**
+```sh
+# Clear all state
+curl -X DELETE http://127.0.0.1:8000/v1/state
+
+# Returns HTTP 204 No Content on success
+```
+
+### Usage Examples
+
+1. **Inspect state after GNMI operations:**
+   ```sh
+   # Set a value via GNMI
+   gnmic -a 127.0.0.1 --port 9339 --insecure set --update-path /System/name --update-value "leaf1"
+   
+   # Check the state via HTTP
+   curl http://127.0.0.1:8000/v1/state
+   ```
+
+2. **Reset state for testing:**
+   ```sh
+   # Clear all state
+   curl -X DELETE http://127.0.0.1:8000/v1/state
+   
+   # Verify state is empty
+   curl http://127.0.0.1:8000/v1/state
+   ```
+
+The HTTP API is particularly useful for:
+- Debugging and inspecting the current state
+- Automated testing scenarios where you need to reset state between tests
+- Integration with monitoring tools that can consume JSON over HTTP

test/gnmi/main.go

@@ -7,6 +7,7 @@ import (
 	"io"
 	"log"
 	"net"
+	"net/http"
 	"strconv"
 	"strings"
 	"time"
@@ -256,9 +257,29 @@ func (s *State) Del(path *gpb.Path) {
 	s.Buf, _ = sjson.DeleteBytes(s.Buf, sb.String()) //nolint:errcheck
 }
 
+// handleState handles HTTP requests to the /v1/state endpoint
+func (s *Server) handleState(w http.ResponseWriter, r *http.Request) {
+	switch r.Method {
+	case http.MethodGet:
+		w.Header().Set("Content-Type", "application/json")
+		w.WriteHeader(http.StatusOK)
+		if len(s.State.Buf) == 0 {
+			w.Write([]byte("{}"))
+			return
+		}
+		w.Write(s.State.Buf)
+	case http.MethodDelete:
+		s.State.Buf = nil
+		w.WriteHeader(http.StatusNoContent)
+	default:
+		w.WriteHeader(http.StatusMethodNotAllowed)
+	}
+}
+
 func main() {
 	// Parse command line flags
-	port := flag.Int("port", 9339, "The server port")
+	port := flag.Int("port", 9339, "The gRPC server port")
+	httpPort := flag.Int("http-port", 8000, "The HTTP server port")
 	flag.Parse()
 
 	// Create a listener on the specified port
@@ -282,9 +303,23 @@ func main() {
 	// Enable reflection for easier testing with tools like grpcurl
 	reflection.Register(grpcServer)
 
+	// Setup HTTP server
+	http.HandleFunc("/v1/state", server.handleState)
+	httpServer := &http.Server{Addr: fmt.Sprintf(":%d", *httpPort)}
+
+	// Start HTTP server in a goroutine
+	go func() {
+		log.Printf("Starting HTTP server on port %d", *httpPort)
+		log.Printf("HTTP endpoint available at: /v1/state")
+		if err := httpServer.ListenAndServe(); err != nil && err != http.ErrServerClosed {
+			log.Fatalf("Failed to serve HTTP server: %v", err)
+		}
+	}()
+
 	log.Printf("Starting gRPC server on port %d", *port)
 	log.Printf("Server is ready to accept connections...")
-	log.Printf("Use --port flag to specify a different port (default: 9339)")
+	log.Printf("Use --port flag to specify a different gRPC port (default: 9339)")
+	log.Printf("Use --http-port flag to specify a different HTTP port (default: 8000)")
 	log.Printf("Available services: GNMI")
 
 	// Start serving