Initial OSS logging adapter for http

internal/ghmcp/server.go

@@ -128,6 +128,7 @@ func NewStdioMCPServer(ctx context.Context, cfg github.MCPServerConfig) (*mcp.Se
 		},
 		cfg.ContentWindowSize,
 		featureChecker,
+		cfg.Logger,
 	)
 	// Build and register the tool/resource/prompt inventory
 	inventoryBuilder := github.NewInventory(cfg.Translator).

pkg/github/dependencies.go

@@ -4,13 +4,17 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"log/slog"
 	"net/http"
 	"os"
 
 	ghcontext "github.com/github/github-mcp-server/pkg/context"
 	"github.com/github/github-mcp-server/pkg/http/transport"
 	"github.com/github/github-mcp-server/pkg/inventory"
 	"github.com/github/github-mcp-server/pkg/lockdown"
+	"github.com/github/github-mcp-server/pkg/observability"
+	obsvLog "github.com/github/github-mcp-server/pkg/observability/log"
+	obsvMetrics "github.com/github/github-mcp-server/pkg/observability/metrics"
 	"github.com/github/github-mcp-server/pkg/raw"
 	"github.com/github/github-mcp-server/pkg/scopes"
 	"github.com/github/github-mcp-server/pkg/translations"
@@ -94,6 +98,12 @@ type ToolDependencies interface {
 
 	// IsFeatureEnabled checks if a feature flag is enabled.
 	IsFeatureEnabled(ctx context.Context, flagName string) bool
+
+	// Logger returns the logger
+	Logger(ctx context.Context) obsvLog.Logger
+
+	// Metrics returns the metrics client
+	Metrics(ctx context.Context) obsvMetrics.Metrics
 }
 
 // BaseDeps is the standard implementation of ToolDependencies for the local server.
@@ -113,6 +123,9 @@ type BaseDeps struct {
 
 	// Feature flag checker for runtime checks
 	featureChecker inventory.FeatureFlagChecker
+
+	// Observability exporters (includes logger)
+	Obsv observability.Exporters
 }
 
 // Compile-time assertion to verify that BaseDeps implements the ToolDependencies interface.
@@ -128,7 +141,14 @@ func NewBaseDeps(
 	flags FeatureFlags,
 	contentWindowSize int,
 	featureChecker inventory.FeatureFlagChecker,
+	logger *slog.Logger,
 ) *BaseDeps {
+	var obsv observability.Exporters
+	if logger != nil {
+		obsv = observability.NewExporters(obsvLog.NewSlogLogger(logger, obsvLog.InfoLevel), obsvMetrics.NewNoopMetrics())
+	} else {
+		obsv = observability.NewExporters(obsvLog.NewNoopLogger(), obsvMetrics.NewNoopMetrics())
+	}
 	return &BaseDeps{
 		Client:            client,
 		GQLClient:         gqlClient,
@@ -138,6 +158,7 @@ func NewBaseDeps(
 		Flags:             flags,
 		ContentWindowSize: contentWindowSize,
 		featureChecker:    featureChecker,
+		Obsv:              obsv,
 	}
 }
 
@@ -170,6 +191,22 @@ func (d BaseDeps) GetFlags(_ context.Context) FeatureFlags { return d.Flags }
 // GetContentWindowSize implements ToolDependencies.
 func (d BaseDeps) GetContentWindowSize() int { return d.ContentWindowSize }
 
+// Logger implements ToolDependencies.
+func (d BaseDeps) Logger(ctx context.Context) obsvLog.Logger {
+	if d.Obsv == nil {
+		return nil
+	}
+	return d.Obsv.Logger(ctx)
+}
+
+// Metrics implements ToolDependencies.
+func (d BaseDeps) Metrics(ctx context.Context) obsvMetrics.Metrics {
+	if d.Obsv == nil {
+		return nil
+	}
+	return d.Obsv.Metrics(ctx)
+}
+
 // IsFeatureEnabled checks if a feature flag is enabled.
 // Returns false if the feature checker is nil, flag name is empty, or an error occurs.
 // This allows tools to conditionally change behavior based on feature flags.
@@ -247,6 +284,9 @@ type RequestDeps struct {
 
 	// Feature flag checker for runtime checks
 	featureChecker inventory.FeatureFlagChecker
+
+	// Observability exporters (includes logger)
+	obsv observability.Exporters
 }
 
 // NewRequestDeps creates a RequestDeps with the provided clients and configuration.
@@ -258,7 +298,14 @@ func NewRequestDeps(
 	t translations.TranslationHelperFunc,
 	contentWindowSize int,
 	featureChecker inventory.FeatureFlagChecker,
+	logger *slog.Logger,
 ) *RequestDeps {
+	var obsv observability.Exporters
+	if logger != nil {
+		obsv = observability.NewExporters(obsvLog.NewSlogLogger(logger, obsvLog.InfoLevel), obsvMetrics.NewNoopMetrics())
+	} else {
+		obsv = observability.NewExporters(obsvLog.NewNoopLogger(), obsvMetrics.NewNoopMetrics())
+	}
 	return &RequestDeps{
 		apiHosts:          apiHosts,
 		version:           version,
@@ -267,6 +314,7 @@ func NewRequestDeps(
 		T:                 t,
 		ContentWindowSize: contentWindowSize,
 		featureChecker:    featureChecker,
+		obsv:              obsv,
 	}
 }
 
@@ -374,6 +422,16 @@ func (d *RequestDeps) GetFlags(ctx context.Context) FeatureFlags {
 // GetContentWindowSize implements ToolDependencies.
 func (d *RequestDeps) GetContentWindowSize() int { return d.ContentWindowSize }
 
+// Logger implements ToolDependencies.
+func (d *RequestDeps) Logger(ctx context.Context) obsvLog.Logger {
+	return d.obsv.Logger(ctx)
+}
+
+// Metrics implements ToolDependencies.
+func (d *RequestDeps) Metrics(ctx context.Context) obsvMetrics.Metrics {
+	return d.obsv.Metrics(ctx)
+}
+
 // IsFeatureEnabled checks if a feature flag is enabled.
 func (d *RequestDeps) IsFeatureEnabled(ctx context.Context, flagName string) bool {
 	if d.featureChecker == nil || flagName == "" {

pkg/github/dependencies_test.go

@@ -28,6 +28,7 @@ func TestIsFeatureEnabled_WithEnabledFlag(t *testing.T) {
 		github.FeatureFlags{},
 		0,       // contentWindowSize
 		checker, // featureChecker
+		nil,     // logger
 	)
 
 	// Test enabled flag
@@ -52,6 +53,7 @@ func TestIsFeatureEnabled_WithoutChecker(t *testing.T) {
 		github.FeatureFlags{},
 		0,   // contentWindowSize
 		nil, // featureChecker (nil)
+		nil, // logger
 	)
 
 	// Should return false when checker is nil
@@ -76,6 +78,7 @@ func TestIsFeatureEnabled_EmptyFlagName(t *testing.T) {
 		github.FeatureFlags{},
 		0,       // contentWindowSize
 		checker, // featureChecker
+		nil,     // logger
 	)
 
 	// Should return false for empty flag name
@@ -100,6 +103,7 @@ func TestIsFeatureEnabled_CheckerError(t *testing.T) {
 		github.FeatureFlags{},
 		0,       // contentWindowSize
 		checker, // featureChecker
+		nil,     // logger
 	)
 
 	// Should return false and log error (not crash)

pkg/github/dynamic_tools_test.go

@@ -136,7 +136,7 @@ func TestDynamicTools_EnableToolset(t *testing.T) {
 	deps := DynamicToolDependencies{
 		Server:    server,
 		Inventory: reg,
-		ToolDeps:  NewBaseDeps(nil, nil, nil, nil, translations.NullTranslationHelper, FeatureFlags{}, 0, nil),
+		ToolDeps:  NewBaseDeps(nil, nil, nil, nil, translations.NullTranslationHelper, FeatureFlags{}, 0, nil, nil),
 		T:         translations.NullTranslationHelper,
 	}
 

pkg/github/feature_flags_test.go

@@ -104,6 +104,7 @@ func TestHelloWorld_ConditionalBehavior_Featureflag(t *testing.T) {
 				FeatureFlags{},
 				0,
 				checker,
+				nil,
 			)
 
 			// Get the tool and its handler
@@ -166,6 +167,7 @@ func TestHelloWorld_ConditionalBehavior_Config(t *testing.T) {
 				FeatureFlags{InsidersMode: tt.insidersMode},
 				0,
 				nil,
+				nil,
 			)
 
 			// Get the tool and its handler

pkg/github/server_test.go

@@ -10,6 +10,9 @@ import (
 	"time"
 
 	"github.com/github/github-mcp-server/pkg/lockdown"
+	"github.com/github/github-mcp-server/pkg/observability"
+	mcpLog "github.com/github/github-mcp-server/pkg/observability/log"
+	mcpMetrics "github.com/github/github-mcp-server/pkg/observability/metrics"
 	"github.com/github/github-mcp-server/pkg/raw"
 	"github.com/github/github-mcp-server/pkg/translations"
 	gogithub "github.com/google/go-github/v82/github"
@@ -29,6 +32,7 @@ type stubDeps struct {
 	t                 translations.TranslationHelperFunc
 	flags             FeatureFlags
 	contentWindowSize int
+	obsv              observability.Exporters
 }
 
 func (s stubDeps) GetClient(ctx context.Context) (*gogithub.Client, error) {
@@ -59,6 +63,18 @@ func (s stubDeps) GetT() translations.TranslationHelperFunc          { return s.
 func (s stubDeps) GetFlags(_ context.Context) FeatureFlags           { return s.flags }
 func (s stubDeps) GetContentWindowSize() int                         { return s.contentWindowSize }
 func (s stubDeps) IsFeatureEnabled(_ context.Context, _ string) bool { return false }
+func (s stubDeps) Logger(ctx context.Context) mcpLog.Logger {
+	if s.obsv != nil {
+		return s.obsv.Logger(ctx)
+	}
+	return mcpLog.NewNoopLogger()
+}
+func (s stubDeps) Metrics(ctx context.Context) mcpMetrics.Metrics {
+	if s.obsv != nil {
+		return s.obsv.Metrics(ctx)
+	}
+	return mcpMetrics.NewNoopMetrics()
+}
 
 // Helper functions to create stub client functions for error testing
 func stubClientFnFromHTTP(httpClient *http.Client) func(context.Context) (*gogithub.Client, error) {

pkg/http/server.go

@@ -114,6 +114,7 @@ func RunHTTPServer(cfg ServerConfig) error {
 		t,
 		cfg.ContentWindowSize,
 		featureChecker,
+		logger,
 	)
 
 	// Initialize the global tool scope map

pkg/observability/log/field.go

@@ -0,0 +1,29 @@
+package log
+
+import (
+	"fmt"
+	"time"
+)
+
+// Field is a key-value pair for structured logging.
+// This type is backend-agnostic — adapters convert it to their native field type.
+type Field struct {
+	Key   string
+	Value any
+}
+
+// Convenience constructors for common field types.
+
+func String(key, value string) Field                 { return Field{Key: key, Value: value} }
+func Int(key string, value int) Field                { return Field{Key: key, Value: value} }
+func Int64(key string, value int64) Field            { return Field{Key: key, Value: value} }
+func Float64(key string, value float64) Field        { return Field{Key: key, Value: value} }
+func Bool(key string, value bool) Field              { return Field{Key: key, Value: value} }
+func Err(err error) Field                            { return Field{Key: "error", Value: err} }
+func Duration(key string, value time.Duration) Field { return Field{Key: key, Value: value} }
+func Any(key string, value any) Field                { return Field{Key: key, Value: value} }
+
+// Stringer returns the string representation of a Field.
+func (f Field) String() string {
+	return fmt.Sprintf("%s=%v", f.Key, f.Value)
+}

pkg/observability/log/level.go

@@ -0,0 +1,23 @@
+package log
+
+type Level struct {
+	level string
+}
+
+var (
+	// DebugLevel causes all logs to be logged
+	DebugLevel = Level{"debug"}
+	// InfoLevel causes all logs of level info or more severe to be logged
+	InfoLevel = Level{"info"}
+	// WarnLevel causes all logs of level warn or more severe to be logged
+	WarnLevel = Level{"warn"}
+	// ErrorLevel causes all logs of level error or more severe to be logged
+	ErrorLevel = Level{"error"}
+	// FatalLevel causes only logs of level fatal to be logged
+	FatalLevel = Level{"fatal"}
+)
+
+// String returns the string representation for Level
+func (l Level) String() string {
+	return l.level
+}

pkg/observability/log/logger.go

@@ -0,0 +1,20 @@
+package log
+
+import (
+	"context"
+)
+
+type Logger interface {
+	Log(ctx context.Context, level Level, msg string, fields ...Field)
+	Debug(msg string, fields ...Field)
+	Info(msg string, fields ...Field)
+	Warn(msg string, fields ...Field)
+	Error(msg string, fields ...Field)
+	Fatal(msg string, fields ...Field)
+	WithFields(fields ...Field) Logger
+	WithError(err error) Logger
+	Named(name string) Logger
+	WithLevel(level Level) Logger
+	Sync() error
+	Level() Level
+}

pkg/observability/log/noop_adapter.go

@@ -0,0 +1,61 @@
+package log
+
+import (
+	"context"
+)
+
+type NoopLogger struct{}
+
+var _ Logger = (*NoopLogger)(nil)
+
+func NewNoopLogger() *NoopLogger {
+	return &NoopLogger{}
+}
+
+func (l *NoopLogger) Level() Level {
+	return DebugLevel
+}
+
+func (l *NoopLogger) Log(_ context.Context, _ Level, _ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) Debug(_ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) Info(_ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) Warn(_ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) Error(_ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) Fatal(_ string, _ ...Field) {
+	// No-op
+}
+
+func (l *NoopLogger) WithFields(_ ...Field) Logger {
+	return l
+}
+
+func (l *NoopLogger) WithError(_ error) Logger {
+	return l
+}
+
+func (l *NoopLogger) Named(_ string) Logger {
+	return l
+}
+
+func (l *NoopLogger) WithLevel(_ Level) Logger {
+	return l
+}
+
+func (l *NoopLogger) Sync() error {
+	return nil
+}