Merge pull request #343 from stevvooe/tracing-driver

context, storagedriver: trace function calls to Base storage driver

docs/handlers/app.go

@@ -8,7 +8,6 @@ import (
 	"os"
 	"time"
 
-	"code.google.com/p/go-uuid/uuid"
 	"github.com/docker/distribution"
 	"github.com/docker/distribution/configuration"
 	ctxu "github.com/docker/distribution/context"
@@ -32,11 +31,8 @@ import (
 // fields should be protected.
 type App struct {
 	context.Context
-	Config configuration.Configuration
 
-	// InstanceID is a unique id assigned to the application on each creation.
-	// Provides information in the logs and context to identify restarts.
-	InstanceID string
+	Config configuration.Configuration
 
 	router           *mux.Router                 // main application router, configured with dispatchers
 	driver           storagedriver.StorageDriver // driver maintains the app global storage driver instance.
@@ -52,17 +48,6 @@ type App struct {
 	redis *redis.Pool
 }
 
-// Value intercepts calls context.Context.Value, returning the current app id,
-// if requested.
-func (app *App) Value(key interface{}) interface{} {
-	switch key {
-	case "app.id":
-		return app.InstanceID
-	}
-
-	return app.Context.Value(key)
-}
-
 // NewApp takes a configuration and returns a configured app, ready to serve
 // requests. The app only implements ServeHTTP and can be wrapped in other
 // handlers accordingly.
@@ -70,11 +55,10 @@ func NewApp(ctx context.Context, configuration configuration.Configuration) *App
 	app := &App{
 		Config:  configuration,
 		Context: ctx,
-		InstanceID: uuid.New(),
 		router:  v2.RouterWithPrefix(configuration.HTTP.Prefix),
 	}
 
-	app.Context = ctxu.WithLogger(app.Context, ctxu.GetLogger(app, "app.id"))
+	app.Context = ctxu.WithLogger(app.Context, ctxu.GetLogger(app, "instance.id"))
 
 	// Register the handler dispatchers.
 	app.register(v2.RouteNameBase, func(ctx *Context, r *http.Request) http.Handler {
@@ -200,7 +184,7 @@ func (app *App) configureEvents(configuration *configuration.Configuration) {
 
 	app.events.source = notifications.SourceRecord{
 		Addr:       hostname,
-		InstanceID: app.InstanceID,
+		InstanceID: ctxu.GetStringValue(app, "instance.id"),
 	}
 }
 

docs/storage/driver/base/base.go

@@ -40,6 +40,7 @@ package base
 import (
 	"io"
 
+	"github.com/docker/distribution/context"
 	storagedriver "github.com/docker/distribution/registry/storage/driver"
 )
 
@@ -51,6 +52,9 @@ type Base struct {
 
 // GetContent wraps GetContent of underlying storage driver.
 func (base *Base) GetContent(path string) ([]byte, error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.GetContent")
+
 	if !storagedriver.PathRegexp.MatchString(path) {
 		return nil, storagedriver.InvalidPathError{Path: path}
 	}
@@ -60,6 +64,9 @@ func (base *Base) GetContent(path string) ([]byte, error) {
 
 // PutContent wraps PutContent of underlying storage driver.
 func (base *Base) PutContent(path string, content []byte) error {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.PutContent")
+
 	if !storagedriver.PathRegexp.MatchString(path) {
 		return storagedriver.InvalidPathError{Path: path}
 	}
@@ -69,6 +76,9 @@ func (base *Base) PutContent(path string, content []byte) error {
 
 // ReadStream wraps ReadStream of underlying storage driver.
 func (base *Base) ReadStream(path string, offset int64) (io.ReadCloser, error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.ReadStream")
+
 	if offset < 0 {
 		return nil, storagedriver.InvalidOffsetError{Path: path, Offset: offset}
 	}
@@ -82,6 +92,9 @@ func (base *Base) ReadStream(path string, offset int64) (io.ReadCloser, error) {
 
 // WriteStream wraps WriteStream of underlying storage driver.
 func (base *Base) WriteStream(path string, offset int64, reader io.Reader) (nn int64, err error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.WriteStream")
+
 	if offset < 0 {
 		return 0, storagedriver.InvalidOffsetError{Path: path, Offset: offset}
 	}
@@ -95,6 +108,9 @@ func (base *Base) WriteStream(path string, offset int64, reader io.Reader) (nn i
 
 // Stat wraps Stat of underlying storage driver.
 func (base *Base) Stat(path string) (storagedriver.FileInfo, error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.Stat")
+
 	if !storagedriver.PathRegexp.MatchString(path) {
 		return nil, storagedriver.InvalidPathError{Path: path}
 	}
@@ -104,6 +120,9 @@ func (base *Base) Stat(path string) (storagedriver.FileInfo, error) {
 
 // List wraps List of underlying storage driver.
 func (base *Base) List(path string) ([]string, error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.List")
+
 	if !storagedriver.PathRegexp.MatchString(path) && path != "/" {
 		return nil, storagedriver.InvalidPathError{Path: path}
 	}
@@ -113,6 +132,9 @@ func (base *Base) List(path string) ([]string, error) {
 
 // Move wraps Move of underlying storage driver.
 func (base *Base) Move(sourcePath string, destPath string) error {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.Move")
+
 	if !storagedriver.PathRegexp.MatchString(sourcePath) {
 		return storagedriver.InvalidPathError{Path: sourcePath}
 	} else if !storagedriver.PathRegexp.MatchString(destPath) {
@@ -124,6 +146,9 @@ func (base *Base) Move(sourcePath string, destPath string) error {
 
 // Delete wraps Delete of underlying storage driver.
 func (base *Base) Delete(path string) error {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.Move")
+
 	if !storagedriver.PathRegexp.MatchString(path) {
 		return storagedriver.InvalidPathError{Path: path}
 	}
@@ -133,6 +158,9 @@ func (base *Base) Delete(path string) error {
 
 // URLFor wraps URLFor of underlying storage driver.
 func (base *Base) URLFor(path string, options map[string]interface{}) (string, error) {
+	_, done := context.WithTrace(context.Background())
+	defer done("Base.URLFor")
+
 	if !storagedriver.PathRegexp.MatchString(path) {
 		return "", storagedriver.InvalidPathError{Path: path}
 	}