forgejo-mcp/pkg/forgejo/forgejo.go
Byte Flavour 4969ee5881
feat: robust stateless auth with security fixes and improved tests
This commit addresses the review feedback on PR #138:
- Fixed a privilege escalation vulnerability where failed ephemeral client
  creation would silently fall back to the global singleton token.
- Refactored forgejo.Client(ctx) to return (*forgejo.Client, error).
- Updated all 100+ tool handlers to properly handle client initialization errors.
- Improved token extraction to handle schemes (token/bearer) case-insensitively.
- Enhanced Unit Tests (pkg/forgejo/forgejo_test.go) to verify that different
  concurrent requests with different tokens correctly use their respective
  tokens in the Authorization header.
- Updated README and demos to reflect case-insensitivity support.
2026-05-24 13:44:48 +02:00

181 lines
4.8 KiB
Go

package forgejo
import (
"context"
"fmt"
"sync"
"time"
"codeberg.org/goern/forgejo-mcp/v2/pkg/flag"
"codeberg.org/goern/forgejo-mcp/v2/pkg/log"
"codeberg.org/mvdkleijn/forgejo-sdk/forgejo/v3"
)
var (
client *forgejo.Client
clientOnce sync.Once
)
type contextKey string
const (
TokenContextKey contextKey = "forgejo-token"
)
// WithToken adds a Forgejo token to the context.
func WithToken(ctx context.Context, token string) context.Context {
return context.WithValue(ctx, TokenContextKey, token)
}
// Client returns a Forgejo client configured to connect to a Forgejo instance.
// If a token is found in the context, a new ephemeral client is returned.
// Otherwise, the shared singleton client is used.
func Client(ctx context.Context) (*forgejo.Client, error) {
token, ok := ctx.Value(TokenContextKey).(string)
if ok && token != "" {
// Use configured user agent or default to forgejo-mcp/<version>
userAgent := flag.UserAgent
if userAgent == "" {
userAgent = "forgejo-mcp/" + flag.Version
}
c, err := forgejo.NewClient(flag.URL,
forgejo.SetToken(token),
forgejo.SetUserAgent(userAgent),
)
if err != nil {
log.ErrorCtx(ctx, "Failed to create ephemeral Forgejo client",
log.SanitizedURLField("url", flag.URL),
log.ErrorField(err),
)
return nil, fmt.Errorf("create ephemeral client: %w", err)
}
return c, nil
}
clientOnce.Do(func() {
if client == nil {
// Use configured user agent or default to forgejo-mcp/<version>
userAgent := flag.UserAgent
if userAgent == "" {
userAgent = "forgejo-mcp/" + flag.Version
}
c, err := forgejo.NewClient(flag.URL,
forgejo.SetToken(flag.Token),
forgejo.SetUserAgent(userAgent),
)
if err != nil {
log.Error("Failed to create Forgejo client",
log.SanitizedURLField("url", flag.URL),
log.ErrorField(err),
)
// We still fatal here because if the singleton can't be created at startup,
// the server is useless in stdio mode.
log.Fatalf("create forgejo client err: %v", err)
}
client = c
log.Info("Successfully created Forgejo client",
log.SanitizedURLField("url", flag.URL),
log.BoolField("token_configured", flag.Token != ""),
log.StringField("user_agent", userAgent),
)
}
})
return client, nil
}
// GetBaseURL returns the base URL of the Forgejo instance.
func GetBaseURL() string {
return flag.URL
}
// VerifyConnection attempts to get basic information to verify
// that the client is properly connected.
// Uses the /version endpoint (no auth required) so that tokens scoped
// only to repo/issue — e.g. organisation tokens — are not rejected.
func VerifyConnection() error {
start := time.Now()
log.Debug("Starting connection verification",
log.SanitizedURLField("url", flag.URL),
)
client, err := Client(context.Background())
if err != nil {
return err
}
version, resp, err := client.ServerVersion()
duration := time.Since(start)
if err != nil {
log.Error("Connection verification failed",
log.SanitizedURLField("url", flag.URL),
log.DurationField("duration", duration),
log.ErrorField(err),
)
return fmt.Errorf("failed to connect to Forgejo instance at %s: %v", flag.URL, err)
}
log.Info("Connection verification successful",
log.SanitizedURLField("url", flag.URL),
log.DurationField("duration", duration),
log.StringField("server_version", version),
log.IntField("response_status", resp.StatusCode),
)
return nil
}
// HealthCheck performs a lightweight health check
func HealthCheck() error {
start := time.Now()
log.Debug("Starting health check")
client, err := Client(context.Background())
if err != nil {
return err
}
version, resp, err := client.ServerVersion()
duration := time.Since(start)
if err != nil {
log.Error("Health check failed",
log.SanitizedURLField("url", flag.URL),
log.DurationField("duration", duration),
log.ErrorField(err),
)
return fmt.Errorf("health check failed: %v", err)
}
log.Debug("Health check successful",
log.SanitizedURLField("url", flag.URL),
log.DurationField("duration", duration),
log.StringField("server_version", version),
log.IntField("response_status", resp.StatusCode),
)
return nil
}
// LogAPICall logs API call information with timing
func LogAPICall(ctx context.Context, method, endpoint string, duration time.Duration, statusCode int, err error) {
if err != nil {
log.ErrorCtx(ctx, "API call failed",
log.StringField("method", method),
log.StringField("endpoint", endpoint),
log.DurationField("duration", duration),
log.IntField("status_code", statusCode),
log.ErrorField(err),
)
} else {
log.DebugCtx(ctx, "API call completed",
log.StringField("method", method),
log.StringField("endpoint", endpoint),
log.DurationField("duration", duration),
log.IntField("status_code", statusCode),
)
}
}