Merge pull request #343 from stevvooe/tracing-driver

context, storagedriver: trace function calls to Base storage driver
This commit is contained in:
Richard Scothern 2015-04-10 16:55:57 -07:00
commit 90af0f9b7a
6 changed files with 254 additions and 36 deletions

View file

@ -16,7 +16,7 @@ import (
"github.com/Sirupsen/logrus/formatters/logstash" "github.com/Sirupsen/logrus/formatters/logstash"
"github.com/bugsnag/bugsnag-go" "github.com/bugsnag/bugsnag-go"
"github.com/docker/distribution/configuration" "github.com/docker/distribution/configuration"
ctxu "github.com/docker/distribution/context" "github.com/docker/distribution/context"
_ "github.com/docker/distribution/health" _ "github.com/docker/distribution/health"
_ "github.com/docker/distribution/registry/auth/silly" _ "github.com/docker/distribution/registry/auth/silly"
_ "github.com/docker/distribution/registry/auth/token" _ "github.com/docker/distribution/registry/auth/token"
@ -29,7 +29,6 @@ import (
"github.com/docker/distribution/version" "github.com/docker/distribution/version"
gorhandlers "github.com/gorilla/handlers" gorhandlers "github.com/gorilla/handlers"
"github.com/yvasiyarov/gorelic" "github.com/yvasiyarov/gorelic"
"golang.org/x/net/context"
) )
var showVersion bool var showVersion bool
@ -68,9 +67,9 @@ func main() {
} }
if config.HTTP.TLS.Certificate == "" { if config.HTTP.TLS.Certificate == "" {
ctxu.GetLogger(app).Infof("listening on %v", config.HTTP.Addr) context.GetLogger(app).Infof("listening on %v", config.HTTP.Addr)
if err := http.ListenAndServe(config.HTTP.Addr, handler); err != nil { if err := http.ListenAndServe(config.HTTP.Addr, handler); err != nil {
ctxu.GetLogger(app).Fatalln(err) context.GetLogger(app).Fatalln(err)
} }
} else { } else {
tlsConf := &tls.Config{ tlsConf := &tls.Config{
@ -83,23 +82,23 @@ func main() {
for _, ca := range config.HTTP.TLS.ClientCAs { for _, ca := range config.HTTP.TLS.ClientCAs {
caPem, err := ioutil.ReadFile(ca) caPem, err := ioutil.ReadFile(ca)
if err != nil { if err != nil {
ctxu.GetLogger(app).Fatalln(err) context.GetLogger(app).Fatalln(err)
} }
if ok := pool.AppendCertsFromPEM(caPem); !ok { if ok := pool.AppendCertsFromPEM(caPem); !ok {
ctxu.GetLogger(app).Fatalln(fmt.Errorf("Could not add CA to pool")) context.GetLogger(app).Fatalln(fmt.Errorf("Could not add CA to pool"))
} }
} }
for _, subj := range pool.Subjects() { for _, subj := range pool.Subjects() {
ctxu.GetLogger(app).Debugf("CA Subject: %s", string(subj)) context.GetLogger(app).Debugf("CA Subject: %s", string(subj))
} }
tlsConf.ClientAuth = tls.RequireAndVerifyClientCert tlsConf.ClientAuth = tls.RequireAndVerifyClientCert
tlsConf.ClientCAs = pool tlsConf.ClientCAs = pool
} }
ctxu.GetLogger(app).Infof("listening on %v, tls", config.HTTP.Addr) context.GetLogger(app).Infof("listening on %v, tls", config.HTTP.Addr)
server := &http.Server{ server := &http.Server{
Addr: config.HTTP.Addr, Addr: config.HTTP.Addr,
Handler: handler, Handler: handler,
@ -107,7 +106,7 @@ func main() {
} }
if err := server.ListenAndServeTLS(config.HTTP.TLS.Certificate, config.HTTP.TLS.Key); err != nil { if err := server.ListenAndServeTLS(config.HTTP.TLS.Certificate, config.HTTP.TLS.Key); err != nil {
ctxu.GetLogger(app).Fatalln(err) context.GetLogger(app).Fatalln(err)
} }
} }
} }
@ -191,7 +190,7 @@ func configureLogging(ctx context.Context, config *configuration.Configuration)
if config.Log.Level == "" && config.Log.Formatter == "" { if config.Log.Level == "" && config.Log.Formatter == "" {
// If no config for logging is set, fallback to deprecated "Loglevel". // If no config for logging is set, fallback to deprecated "Loglevel".
log.SetLevel(logLevel(config.Loglevel)) log.SetLevel(logLevel(config.Loglevel))
ctx = ctxu.WithLogger(ctx, ctxu.GetLogger(ctx, "version")) ctx = context.WithLogger(ctx, context.GetLogger(ctx, "version"))
return ctx, nil return ctx, nil
} }
@ -236,8 +235,8 @@ func configureLogging(ctx context.Context, config *configuration.Configuration)
fields = append(fields, k) fields = append(fields, k)
} }
ctx = ctxu.WithValues(ctx, config.Log.Fields) ctx = context.WithValues(ctx, config.Log.Fields)
ctx = ctxu.WithLogger(ctx, ctxu.GetLogger(ctx, fields...)) ctx = context.WithLogger(ctx, context.GetLogger(ctx, fields...))
} }
return ctx, nil return ctx, nil

View file

@ -1,6 +1,7 @@
package context package context
import ( import (
"code.google.com/p/go-uuid/uuid"
"golang.org/x/net/context" "golang.org/x/net/context"
) )
@ -9,9 +10,31 @@ type Context interface {
context.Context context.Context
} }
// Background returns a non-nil, empty Context. // instanceContext is a context that provides only an instance id. It is
// provided as the main background context.
type instanceContext struct {
Context
id string // id of context, logged as "instance.id"
}
func (ic *instanceContext) Value(key interface{}) interface{} {
if key == "instance.id" {
return ic.id
}
return ic.Context.Value(key)
}
var background = &instanceContext{
Context: context.Background(),
id: uuid.New(),
}
// Background returns a non-nil, empty Context. The background context
// provides a single key, "instance.id" that is globally unique to the
// process.
func Background() Context { func Background() Context {
return context.Background() return background
} }
// WithValue returns a copy of parent in which the value associated with key is // WithValue returns a copy of parent in which the value associated with key is

99
context/trace.go Normal file
View file

@ -0,0 +1,99 @@
package context
import (
"runtime"
"time"
"code.google.com/p/go-uuid/uuid"
)
// WithTrace allocates a traced timing span in a new context. This allows a
// caller to track the time between calling WithTrace and the returned done
// function. When the done function is called, a log message is emitted with a
// "trace.duration" field, corresponding to the elapased time and a
// "trace.func" field, corresponding to the function that called WithTrace.
//
// The logging keys "trace.id" and "trace.parent.id" are provided to implement
// dapper-like tracing. This function should be complemented with a WithSpan
// method that could be used for tracing distributed RPC calls.
//
// The main benefit of this function is to post-process log messages or
// intercept them in a hook to provide timing data. Trace ids and parent ids
// can also be linked to provide call tracing, if so required.
//
// Here is an example of the usage:
//
// func timedOperation(ctx Context) {
// ctx, done := WithTrace(ctx)
// defer done("this will be the log message")
// // ... function body ...
// }
//
// If the function ran for roughly 1s, such a usage would emit a log message
// as follows:
//
// INFO[0001] this will be the log message trace.duration=1.004575763s trace.func=github.com/docker/distribution/context.traceOperation trace.id=<id> ...
//
// Notice that the function name is automatically resolved, along with the
// package and a trace id is emitted that can be linked with parent ids.
func WithTrace(ctx Context) (Context, func(format string, a ...interface{})) {
if ctx == nil {
ctx = Background()
}
pc, file, line, _ := runtime.Caller(1)
f := runtime.FuncForPC(pc)
ctx = &traced{
Context: ctx,
id: uuid.New(),
start: time.Now(),
parent: GetStringValue(ctx, "trace.id"),
fnname: f.Name(),
file: file,
line: line,
}
return ctx, func(format string, a ...interface{}) {
GetLogger(ctx, "trace.duration", "trace.id", "trace.parent.id",
"trace.func", "trace.file", "trace.line").
Infof(format, a...) // info may be too chatty.
}
}
// traced represents a context that is traced for function call timing. It
// also provides fast lookup for the various attributes that are available on
// the trace.
type traced struct {
Context
id string
parent string
start time.Time
fnname string
file string
line int
}
func (ts *traced) Value(key interface{}) interface{} {
switch key {
case "trace.start":
return ts.start
case "trace.duration":
return time.Since(ts.start)
case "trace.id":
return ts.id
case "trace.parent.id":
if ts.parent == "" {
return nil // must return nil to signal no parent.
}
return ts.parent
case "trace.func":
return ts.fnname
case "trace.file":
return ts.file
case "trace.line":
return ts.line
}
return ts.Context.Value(key)
}

85
context/trace_test.go Normal file
View file

@ -0,0 +1,85 @@
package context
import (
"runtime"
"testing"
"time"
)
// TestWithTrace ensures that tracing has the expected values in the context.
func TestWithTrace(t *testing.T) {
pc, file, _, _ := runtime.Caller(0) // get current caller.
f := runtime.FuncForPC(pc)
base := []valueTestCase{
{
key: "trace.id",
notnilorempty: true,
},
{
key: "trace.file",
expected: file,
notnilorempty: true,
},
{
key: "trace.line",
notnilorempty: true,
},
{
key: "trace.start",
notnilorempty: true,
},
}
ctx, done := WithTrace(Background())
defer done("this will be emitted at end of test")
checkContextForValues(t, ctx, append(base, valueTestCase{
key: "trace.func",
expected: f.Name(),
}))
traced := func() {
parentID := ctx.Value("trace.id") // ensure the parent trace id is correct.
pc, _, _, _ := runtime.Caller(0) // get current caller.
f := runtime.FuncForPC(pc)
ctx, done := WithTrace(ctx)
defer done("this should be subordinate to the other trace")
time.Sleep(time.Second)
checkContextForValues(t, ctx, append(base, valueTestCase{
key: "trace.func",
expected: f.Name(),
}, valueTestCase{
key: "trace.parent.id",
expected: parentID,
}))
}
traced()
time.Sleep(time.Second)
}
type valueTestCase struct {
key string
expected interface{}
notnilorempty bool // just check not empty/not nil
}
func checkContextForValues(t *testing.T, ctx Context, values []valueTestCase) {
for _, testcase := range values {
v := ctx.Value(testcase.key)
if testcase.notnilorempty {
if v == nil || v == "" {
t.Fatalf("value was nil or empty for %q: %#v", testcase.key, v)
}
continue
}
if v != testcase.expected {
t.Fatalf("unexpected value for key %q: %v != %v", testcase.key, v, testcase.expected)
}
}
}

View file

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

View file

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