Merge pull request #705 from stevvooe/export-servejson-errors

Export ServeJSON for serving error codes
This commit is contained in:
Stephen Day 2015-07-16 14:35:27 -07:00
commit fed58bd2d3
4 changed files with 65 additions and 44 deletions

View file

@ -16,6 +16,8 @@ type ErrorCoder interface {
// and the integer format may change and should *never* be exported.
type ErrorCode int
var _ error = ErrorCode(0)
// ErrorCode just returns itself
func (ec ErrorCode) ErrorCode() ErrorCode {
return ec
@ -93,6 +95,8 @@ type Error struct {
// variable substitution right before showing the message to the user
}
var _ error = Error{}
// ErrorCode returns the ID/Value of this Error
func (e Error) ErrorCode() ErrorCode {
return e.Code
@ -163,6 +167,8 @@ func ParseErrorCode(value string) ErrorCode {
// for use within the application.
type Errors []error
var _ error = Errors{}
func (errs Errors) Error() string {
switch len(errs) {
case 0:

View file

@ -0,0 +1,44 @@
package errcode
import (
"encoding/json"
"net/http"
)
// ServeJSON attempts to serve the errcode in a JSON envelope. It marshals err
// and sets the content-type header to 'application/json'. It will handle
// ErrorCoder and Errors, and if necessary will create an envelope.
func ServeJSON(w http.ResponseWriter, err error) error {
w.Header().Set("Content-Type", "application/json; charset=utf-8")
var sc int
switch errs := err.(type) {
case Errors:
if len(errs) < 1 {
break
}
if err, ok := errs[0].(ErrorCoder); ok {
sc = err.ErrorCode().Descriptor().HTTPStatusCode
}
case ErrorCoder:
sc = errs.ErrorCode().Descriptor().HTTPStatusCode
err = Errors{err} // create an envelope.
default:
// We just have an unhandled error type, so just place in an envelope
// and move along.
err = Errors{err}
}
if sc == 0 {
sc = http.StatusInternalServerError
}
w.WriteHeader(sc)
if err := json.NewEncoder(w).Encode(err); err != nil {
return err
}
return nil
}

View file

@ -379,7 +379,9 @@ func (app *App) dispatcher(dispatch dispatchFunc) http.Handler {
context.Errors = append(context.Errors, v2.ErrorCodeNameInvalid.WithDetail(err))
}
serveJSON(w, context.Errors)
if err := errcode.ServeJSON(w, context.Errors); err != nil {
ctxu.GetLogger(context).Errorf("error serving error json: %v (from %v)", err, context.Errors)
}
return
}
@ -393,7 +395,9 @@ func (app *App) dispatcher(dispatch dispatchFunc) http.Handler {
ctxu.GetLogger(context).Errorf("error initializing repository middleware: %v", err)
context.Errors = append(context.Errors, errcode.ErrorCodeUnknown.WithDetail(err))
serveJSON(w, context.Errors)
if err := errcode.ServeJSON(w, context.Errors); err != nil {
ctxu.GetLogger(context).Errorf("error serving error json: %v (from %v)", err, context.Errors)
}
return
}
}
@ -405,7 +409,9 @@ func (app *App) dispatcher(dispatch dispatchFunc) http.Handler {
if context.Errors.Len() > 0 {
app.logError(context, context.Errors)
serveJSON(w, context.Errors)
if err := errcode.ServeJSON(w, context.Errors); err != nil {
ctxu.GetLogger(context).Errorf("error serving error json: %v (from %v)", err, context.Errors)
}
}
})
}
@ -482,11 +488,9 @@ func (app *App) authorized(w http.ResponseWriter, r *http.Request, context *Cont
// base route is accessed. This section prevents us from making
// that mistake elsewhere in the code, allowing any operation to
// proceed.
var errs errcode.Errors
errs = append(errs, v2.ErrorCodeUnauthorized)
serveJSON(w, errs)
if err := errcode.ServeJSON(w, v2.ErrorCodeUnauthorized); err != nil {
ctxu.GetLogger(context).Errorf("error serving error json: %v (from %v)", err, context.Errors)
}
return fmt.Errorf("forbidden: no repository name")
}
}
@ -498,9 +502,9 @@ func (app *App) authorized(w http.ResponseWriter, r *http.Request, context *Cont
// Add the appropriate WWW-Auth header
err.ServeHTTP(w, r)
var errs errcode.Errors
errs = append(errs, v2.ErrorCodeUnauthorized.WithDetail(accessRecords))
serveJSON(w, errs)
if err := errcode.ServeJSON(w, v2.ErrorCodeUnauthorized.WithDetail(accessRecords)); err != nil {
ctxu.GetLogger(context).Errorf("error serving error json: %v (from %v)", err, context.Errors)
}
default:
// This condition is a potential security problem either in
// the configuration or whatever is backing the access

View file

@ -1,43 +1,10 @@
package handlers
import (
"encoding/json"
"io"
"net/http"
"github.com/docker/distribution/registry/api/errcode"
)
// serveJSON marshals v and sets the content-type header to
// 'application/json'. If a different status code is required, call
// ResponseWriter.WriteHeader before this function.
func serveJSON(w http.ResponseWriter, v interface{}) error {
w.Header().Set("Content-Type", "application/json; charset=utf-8")
sc := http.StatusInternalServerError
if errs, ok := v.(errcode.Errors); ok && len(errs) > 0 {
if err, ok := errs[0].(errcode.ErrorCoder); ok {
if sc2 := err.ErrorCode().Descriptor().HTTPStatusCode; sc2 != 0 {
sc = sc2
}
}
} else if err, ok := v.(errcode.ErrorCoder); ok {
if sc2 := err.ErrorCode().Descriptor().HTTPStatusCode; sc2 != 0 {
sc = sc2
}
}
w.WriteHeader(sc)
enc := json.NewEncoder(w)
if err := enc.Encode(v); err != nil {
return err
}
return nil
}
// closeResources closes all the provided resources after running the target
// handler.
func closeResources(handler http.Handler, closers ...io.Closer) http.Handler {