modelcontextprotocol/go-sdk
Watch
1
0
Fork
You've already forked go-sdk
 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions 1

mcp: export ClientSessionOptions.ProtocolVersion (#1127)

Browse source 
## Summary

`ClientSessionOptions.protocolVersion` was unexported and documented as
test-only, so external consumers of `Client.Connect` could not request a
specific protocol revision.

This exports the field as `ProtocolVersion` with the same semantics:

- empty → request the latest supported version (unchanged default)
- non-empty → send that version in initialize/discover
- existing negotiate-down path is unchanged

## Usage

```go
cs, err := client.Connect(ctx, transport, &mcp.ClientSessionOptions{
    ProtocolVersion: "2025-11-25",
})
```

## Testing

- `go test ./mcp/ -count=1` (pass)

Fixes #1113

Co-authored-by: arimu1 <19286898+arimu1@users.noreply.github.com>
Co-authored-by: Guglielmo Colombo <guglielmoc@google.com>
This commit is contained in:
dev_Hakaze 2026-08-03 20:29:52 +07:00 • committed by GitHub
commit 1acd66e9d7
No known key found for this signature in database
GPG key ID: B5690EEEBB952194
1 changed files with 73 additions and 72 deletions
Download patch file Download diff file Expand all files Collapse all files

14
mcp/client_test.go
View file

@ -740,7 +740,7 @@ func TestClientConnectDiscover(t *testing.T) {
defer ss.Close()
c := NewClient(testImpl, nil)
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("Connect: %v", err)
}
@ -805,7 +805,7 @@ func TestClientConnectDiscover_RequestContents(t *testing.T) {
return nil, nil
},
})
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("Connect: %v", err)
}
@ -851,7 +851,7 @@ func TestInMemory_E2E_DiscoverSuccess(t *testing.T) {
defer ss.Close()
client := NewClient(&Implementation{Name: "stdio-like-client", Version: "v1"}, nil)
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("client.Connect: %v", err)
}
@ -908,7 +908,7 @@ func TestInMemory_E2E_DiscoverFallback_NoOverlap(t *testing.T) {
defer ss.Close()
client := NewClient(&Implementation{Name: "new-client", Version: "v1"}, nil)
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("client.Connect: %v", err)
}
@ -955,7 +955,7 @@ func TestInMemory_E2E_DiscoverFallback_MethodNotFound(t *testing.T) {
defer ss.Close()
client := NewClient(&Implementation{Name: "new-client", Version: "v1"}, nil)
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("client.Connect: %v", err)
}
@ -1005,7 +1005,7 @@ func TestInMemory_E2E_DiscoverFallback_UnsupportedProtocolVersion(t *testing.T)
defer ss.Close()
client := NewClient(&Implementation{Name: "new-client", Version: "v1"}, nil)
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: protocolVersion20260728})
cs, err := client.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: protocolVersion20260728})
if err != nil {
t.Fatalf("client.Connect: %v", err)
}
@ -1068,7 +1068,7 @@ func TestClientConnectDiscover_UnsupportedVersionNegotiation(t *testing.T) {
defer ss.Close()
c := NewClient(testImpl, nil)
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{protocolVersion: unsupportedClientVersion})
cs, err := c.Connect(ctx, ct, &ClientSessionOptions{ProtocolVersion: unsupportedClientVersion})
if err != nil {
t.Fatalf("Connect: %v", err)
}