minio/cmd/http/close.go

53 lines
1.6 KiB
Go

/*
* Minio Cloud Storage, (C) 2019 Minio, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package http
import (
"io"
"io/ioutil"
"sync"
)
var b512pool = sync.Pool{
New: func() interface{} {
buf := make([]byte, 512)
return &buf
},
}
// DrainBody close non nil response with any response Body.
// convenient wrapper to drain any remaining data on response body.
//
// Subsequently this allows golang http RoundTripper
// to re-use the same connection for future requests.
func DrainBody(respBody io.ReadCloser) {
// Callers should close resp.Body when done reading from it.
// If resp.Body is not closed, the Client's underlying RoundTripper
// (typically Transport) may not be able to re-use a persistent TCP
// connection to the server for a subsequent "keep-alive" request.
if respBody != nil {
// Drain any remaining Body and then close the connection.
// Without this closing connection would disallow re-using
// the same connection for future uses.
// - http://stackoverflow.com/a/17961593/4465767
bufp := b512pool.Get().(*[]byte)
defer b512pool.Put(bufp)
io.CopyBuffer(ioutil.Discard, respBody, *bufp)
respBody.Close()
}
}