distribution/docs/handlers/helpers.go
Aaron Lehmann b51913f619 Set the response code to 499 when a client disconnects during an upload
The response code isn't actually sent to the client, because the
connection has already closed by this point. But it causes the status
code to appear as 499 in the logs instead of 0.

Signed-off-by: Aaron Lehmann <aaron.lehmann@docker.com>
2015-07-31 17:39:30 -07:00

62 lines
2.1 KiB
Go

package handlers
import (
"errors"
"io"
"net/http"
ctxu "github.com/docker/distribution/context"
"github.com/docker/distribution/registry/api/errcode"
)
// closeResources closes all the provided resources after running the target
// handler.
func closeResources(handler http.Handler, closers ...io.Closer) http.Handler {
return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
for _, closer := range closers {
defer closer.Close()
}
handler.ServeHTTP(w, r)
})
}
// copyFullPayload copies the payload of a HTTP request to destWriter. If it
// receives less content than expected, and the client disconnected during the
// upload, it avoids sending a 400 error to keep the logs cleaner.
func copyFullPayload(responseWriter http.ResponseWriter, r *http.Request, destWriter io.Writer, context ctxu.Context, action string, errSlice *errcode.Errors) error {
// Get a channel that tells us if the client disconnects
var clientClosed <-chan bool
if notifier, ok := responseWriter.(http.CloseNotifier); ok {
clientClosed = notifier.CloseNotify()
} else {
panic("the ResponseWriter does not implement CloseNotifier")
}
// Read in the data, if any.
copied, err := io.Copy(destWriter, r.Body)
if clientClosed != nil && (err != nil || (r.ContentLength > 0 && copied < r.ContentLength)) {
// Didn't recieve as much content as expected. Did the client
// disconnect during the request? If so, avoid returning a 400
// error to keep the logs cleaner.
select {
case <-clientClosed:
// Set the response code to "499 Client Closed Request"
// Even though the connection has already been closed,
// this causes the logger to pick up a 499 error
// instead of showing 0 for the HTTP status.
responseWriter.WriteHeader(499)
ctxu.GetLogger(context).Error("client disconnected during " + action)
return errors.New("client disconnected")
default:
}
}
if err != nil {
ctxu.GetLogger(context).Errorf("unknown error reading request payload: %v", err)
*errSlice = append(*errSlice, errcode.ErrorCodeUnknown.WithDetail(err))
return err
}
return nil
}