go-sdk/mcp/cmd_test.go
Rob Findley 56ed3872f3 internal/mcp: add a command transport for connecting to a sidecar
Add a missing CommandTransport that communicates with a sidecar process
over newline-delimited stdin/stdout, the counterpart to the existing
StdIOTransport.

Add a test using the usual TestMain trick.

Change-Id: I170ba78faf6b6d7fca7da1af11bf92e919b11ed5
Reviewed-on: https://go-review.googlesource.com/c/tools/+/668895
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
2025-05-01 17:43:04 -07:00

67 lines
1.5 KiB
Go

// Copyright 2025 The Go MCP SDK Authors. All rights reserved.
// Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.
package mcp_test
import (
"context"
"log"
"os"
"os/exec"
"testing"
"github.com/google/go-cmp/cmp"
"github.com/modelcontextprotocol/go-sdk/mcp"
)
const runAsServer = "_MCP_RUN_AS_SERVER"
func TestMain(m *testing.M) {
if os.Getenv(runAsServer) != "" {
os.Unsetenv(runAsServer)
runServer()
return
}
os.Exit(m.Run())
}
func runServer() {
ctx := context.Background()
server := mcp.NewServer("greeter", "v0.0.1", nil)
server.AddTools(mcp.MakeTool("greet", "say hi", SayHi))
if err := server.Run(ctx, mcp.NewStdIOTransport(), nil); err != nil {
log.Fatal(err)
}
}
func TestCmdTransport(t *testing.T) {
ctx, cancel := context.WithCancel(context.Background())
defer cancel()
exe, err := os.Executable()
if err != nil {
t.Fatal(err)
}
cmd := exec.Command(exe)
cmd.Env = append(os.Environ(), runAsServer+"=true")
client := mcp.NewClient("client", "v0.0.1", nil)
serverConn, err := client.Connect(ctx, mcp.NewCommandTransport(cmd), nil)
if err != nil {
log.Fatal(err)
}
got, err := serverConn.CallTool(ctx, "greet", SayHiParams{Name: "user"})
if err != nil {
log.Fatal(err)
}
want := []mcp.Content{mcp.TextContent{Text: "Hi user"}}
if diff := cmp.Diff(want, got); diff != "" {
t.Errorf("greet returned unexpected content (-want +got):\n%s", diff)
}
if err := serverConn.Close(); err != nil {
t.Fatalf("closing server: %v", err)
}
}