moby/registry/resumable/resumablerequestreader.go
Sebastiaan van Stijn cff4f20c44
migrate to github.com/containerd/log v0.1.0
The github.com/containerd/containerd/log package was moved to a separate
module, which will also be used by upcoming (patch) releases of containerd.

This patch moves our own uses of the package to use the new module.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>
2023-10-11 17:52:23 +02:00

97 lines
3.1 KiB
Go

package resumable // import "github.com/docker/docker/registry/resumable"
import (
"context"
"fmt"
"io"
"net/http"
"time"
"github.com/containerd/log"
)
type requestReader struct {
client *http.Client
request *http.Request
lastRange int64
totalSize int64
currentResponse *http.Response
failures uint32
maxFailures uint32
waitDuration time.Duration
}
// NewRequestReader makes it possible to resume reading a request's body transparently
// maxfail is the number of times we retry to make requests again (not resumes)
// totalsize is the total length of the body; auto detect if not provided
func NewRequestReader(c *http.Client, r *http.Request, maxfail uint32, totalsize int64) io.ReadCloser {
return &requestReader{client: c, request: r, maxFailures: maxfail, totalSize: totalsize, waitDuration: 5 * time.Second}
}
// NewRequestReaderWithInitialResponse makes it possible to resume
// reading the body of an already initiated request.
func NewRequestReaderWithInitialResponse(c *http.Client, r *http.Request, maxfail uint32, totalsize int64, initialResponse *http.Response) io.ReadCloser {
return &requestReader{client: c, request: r, maxFailures: maxfail, totalSize: totalsize, currentResponse: initialResponse, waitDuration: 5 * time.Second}
}
func (r *requestReader) Read(p []byte) (n int, err error) {
if r.client == nil || r.request == nil {
return 0, fmt.Errorf("client and request can't be nil")
}
isFreshRequest := false
if r.lastRange != 0 && r.currentResponse == nil {
readRange := fmt.Sprintf("bytes=%d-%d", r.lastRange, r.totalSize)
r.request.Header.Set("Range", readRange)
time.Sleep(r.waitDuration)
}
if r.currentResponse == nil {
r.currentResponse, err = r.client.Do(r.request)
isFreshRequest = true
}
if err != nil && r.failures+1 != r.maxFailures {
r.cleanUpResponse()
r.failures++
time.Sleep(time.Duration(r.failures) * r.waitDuration)
return 0, nil
} else if err != nil {
r.cleanUpResponse()
return 0, err
}
if r.currentResponse.StatusCode == http.StatusRequestedRangeNotSatisfiable && r.lastRange == r.totalSize && r.currentResponse.ContentLength == 0 {
r.cleanUpResponse()
return 0, io.EOF
} else if r.currentResponse.StatusCode != http.StatusPartialContent && r.lastRange != 0 && isFreshRequest {
r.cleanUpResponse()
return 0, fmt.Errorf("the server doesn't support byte ranges")
}
if r.totalSize == 0 {
r.totalSize = r.currentResponse.ContentLength
} else if r.totalSize <= 0 {
r.cleanUpResponse()
return 0, fmt.Errorf("failed to auto detect content length")
}
n, err = r.currentResponse.Body.Read(p)
r.lastRange += int64(n)
if err != nil {
r.cleanUpResponse()
}
if err != nil && err != io.EOF {
log.G(context.TODO()).Infof("encountered error during pull and clearing it before resume: %s", err)
err = nil
}
return n, err
}
func (r *requestReader) Close() error {
r.cleanUpResponse()
r.client = nil
r.request = nil
return nil
}
func (r *requestReader) cleanUpResponse() {
if r.currentResponse != nil {
r.currentResponse.Body.Close()
r.currentResponse = nil
}
}