1 files changed, 342 insertions, 0 deletions
diff --git a/vendor/google.golang.org/api/gensupport/media.go b/vendor/google.golang.org/api/gensupport/media.go
new file mode 100644
index 000000000..4cef4adbb
--- /dev/null
+++ b/vendor/google.golang.org/api/gensupport/media.go
@@ -0,0 +1,342 @@
+// Copyright 2016 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package gensupport
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime/multipart"
+	"net/http"
+	"net/textproto"
+	"strings"
+	"sync"
+
+	"google.golang.org/api/googleapi"
+)
+
+const sniffBuffSize = 512
+
+func newContentSniffer(r io.Reader) *contentSniffer {
+	return &contentSniffer{r: r}
+}
+
+// contentSniffer wraps a Reader, and reports the content type determined by sniffing up to 512 bytes from the Reader.
+type contentSniffer struct {
+	r     io.Reader
+	start []byte // buffer for the sniffed bytes.
+	err   error  // set to any error encountered while reading bytes to be sniffed.
+
+	ctype   string // set on first sniff.
+	sniffed bool   // set to true on first sniff.
+}
+
+func (cs *contentSniffer) Read(p []byte) (n int, err error) {
+	// Ensure that the content type is sniffed before any data is consumed from Reader.
+	_, _ = cs.ContentType()
+
+	if len(cs.start) > 0 {
+		n := copy(p, cs.start)
+		cs.start = cs.start[n:]
+		return n, nil
+	}
+
+	// We may have read some bytes into start while sniffing, even if the read ended in an error.
+	// We should first return those bytes, then the error.
+	if cs.err != nil {
+		return 0, cs.err
+	}
+
+	// Now we have handled all bytes that were buffered while sniffing.  Now just delegate to the underlying reader.
+	return cs.r.Read(p)
+}
+
+// ContentType returns the sniffed content type, and whether the content type was succesfully sniffed.
+func (cs *contentSniffer) ContentType() (string, bool) {
+	if cs.sniffed {
+		return cs.ctype, cs.ctype != ""
+	}
+	cs.sniffed = true
+	// If ReadAll hits EOF, it returns err==nil.
+	cs.start, cs.err = ioutil.ReadAll(io.LimitReader(cs.r, sniffBuffSize))
+
+	// Don't try to detect the content type based on possibly incomplete data.
+	if cs.err != nil {
+		return "", false
+	}
+
+	cs.ctype = http.DetectContentType(cs.start)
+	return cs.ctype, true
+}
+
+// DetermineContentType determines the content type of the supplied reader.
+// If the content type is already known, it can be specified via ctype.
+// Otherwise, the content of media will be sniffed to determine the content type.
+// If media implements googleapi.ContentTyper (deprecated), this will be used
+// instead of sniffing the content.
+// After calling DetectContentType the caller must not perform further reads on
+// media, but rather read from the Reader that is returned.
+func DetermineContentType(media io.Reader, ctype string) (io.Reader, string) {
+	// Note: callers could avoid calling DetectContentType if ctype != "",
+	// but doing the check inside this function reduces the amount of
+	// generated code.
+	if ctype != "" {
+		return media, ctype
+	}
+
+	// For backwards compatability, allow clients to set content
+	// type by providing a ContentTyper for media.
+	if typer, ok := media.(googleapi.ContentTyper); ok {
+		return media, typer.ContentType()
+	}
+
+	sniffer := newContentSniffer(media)
+	if ctype, ok := sniffer.ContentType(); ok {
+		return sniffer, ctype
+	}
+	// If content type could not be sniffed, reads from sniffer will eventually fail with an error.
+	return sniffer, ""
+}
+
+type typeReader struct {
+	io.Reader
+	typ string
+}
+
+// multipartReader combines the contents of multiple readers to create a multipart/related HTTP body.
+// Close must be called if reads from the multipartReader are abandoned before reaching EOF.
+type multipartReader struct {
+	pr       *io.PipeReader
+	ctype    string
+	mu       sync.Mutex
+	pipeOpen bool
+}
+
+func newMultipartReader(parts []typeReader) *multipartReader {
+	mp := &multipartReader{pipeOpen: true}
+	var pw *io.PipeWriter
+	mp.pr, pw = io.Pipe()
+	mpw := multipart.NewWriter(pw)
+	mp.ctype = "multipart/related; boundary=" + mpw.Boundary()
+	go func() {
+		for _, part := range parts {
+			w, err := mpw.CreatePart(typeHeader(part.typ))
+			if err != nil {
+				mpw.Close()
+				pw.CloseWithError(fmt.Errorf("googleapi: CreatePart failed: %v", err))
+				return
+			}
+			_, err = io.Copy(w, part.Reader)
+			if err != nil {
+				mpw.Close()
+				pw.CloseWithError(fmt.Errorf("googleapi: Copy failed: %v", err))
+				return
+			}
+		}
+
+		mpw.Close()
+		pw.Close()
+	}()
+	return mp
+}
+
+func (mp *multipartReader) Read(data []byte) (n int, err error) {
+	return mp.pr.Read(data)
+}
+
+func (mp *multipartReader) Close() error {
+	mp.mu.Lock()
+	if !mp.pipeOpen {
+		mp.mu.Unlock()
+		return nil
+	}
+	mp.pipeOpen = false
+	mp.mu.Unlock()
+	return mp.pr.Close()
+}
+
+// CombineBodyMedia combines a json body with media content to create a multipart/related HTTP body.
+// It returns a ReadCloser containing the combined body, and the overall "multipart/related" content type, with random boundary.
+//
+// The caller must call Close on the returned ReadCloser if reads are abandoned before reaching EOF.
+func CombineBodyMedia(body io.Reader, bodyContentType string, media io.Reader, mediaContentType string) (io.ReadCloser, string) {
+	mp := newMultipartReader([]typeReader{
+		{body, bodyContentType},
+		{media, mediaContentType},
+	})
+	return mp, mp.ctype
+}
+
+func typeHeader(contentType string) textproto.MIMEHeader {
+	h := make(textproto.MIMEHeader)
+	if contentType != "" {
+		h.Set("Content-Type", contentType)
+	}
+	return h
+}
+
+// PrepareUpload determines whether the data in the supplied reader should be
+// uploaded in a single request, or in sequential chunks.
+// chunkSize is the size of the chunk that media should be split into.
+//
+// If chunkSize is zero, media is returned as the first value, and the other
+// two return values are nil, true.
+//
+// Otherwise, a MediaBuffer is returned, along with a bool indicating whether the
+// contents of media fit in a single chunk.
+//
+// After PrepareUpload has been called, media should no longer be used: the
+// media content should be accessed via one of the return values.
+func PrepareUpload(media io.Reader, chunkSize int) (r io.Reader, mb *MediaBuffer, singleChunk bool) {
+	if chunkSize == 0 { // do not chunk
+		return media, nil, true
+	}
+	mb = NewMediaBuffer(media, chunkSize)
+	_, _, _, err := mb.Chunk()
+	// If err is io.EOF, we can upload this in a single request. Otherwise, err is
+	// either nil or a non-EOF error. If it is the latter, then the next call to
+	// mb.Chunk will return the same error. Returning a MediaBuffer ensures that this
+	// error will be handled at some point.
+	return nil, mb, err == io.EOF
+}
+
+// MediaInfo holds information for media uploads. It is intended for use by generated
+// code only.
+type MediaInfo struct {
+	// At most one of Media and MediaBuffer will be set.
+	media           io.Reader
+	buffer          *MediaBuffer
+	singleChunk     bool
+	mType           string
+	size            int64 // mediaSize, if known.  Used only for calls to progressUpdater_.
+	progressUpdater googleapi.ProgressUpdater
+}
+
+// NewInfoFromMedia should be invoked from the Media method of a call. It returns a
+// MediaInfo populated with chunk size and content type, and a reader or MediaBuffer
+// if needed.
+func NewInfoFromMedia(r io.Reader, options []googleapi.MediaOption) *MediaInfo {
+	mi := &MediaInfo{}
+	opts := googleapi.ProcessMediaOptions(options)
+	if !opts.ForceEmptyContentType {
+		r, mi.mType = DetermineContentType(r, opts.ContentType)
+	}
+	mi.media, mi.buffer, mi.singleChunk = PrepareUpload(r, opts.ChunkSize)
+	return mi
+}
+
+// NewInfoFromResumableMedia should be invoked from the ResumableMedia method of a
+// call. It returns a MediaInfo using the given reader, size and media type.
+func NewInfoFromResumableMedia(r io.ReaderAt, size int64, mediaType string) *MediaInfo {
+	rdr := ReaderAtToReader(r, size)
+	rdr, mType := DetermineContentType(rdr, mediaType)
+	return &MediaInfo{
+		size:        size,
+		mType:       mType,
+		buffer:      NewMediaBuffer(rdr, googleapi.DefaultUploadChunkSize),
+		media:       nil,
+		singleChunk: false,
+	}
+}
+
+// SetProgressUpdater sets the progress updater for the media info.
+func (mi *MediaInfo) SetProgressUpdater(pu googleapi.ProgressUpdater) {
+	if mi != nil {
+		mi.progressUpdater = pu
+	}
+}
+
+// UploadType determines the type of upload: a single request, or a resumable
+// series of requests.
+func (mi *MediaInfo) UploadType() string {
+	if mi.singleChunk {
+		return "multipart"
+	}
+	return "resumable"
+}
+
+// UploadRequest sets up an HTTP request for media upload. It adds headers
+// as necessary, and returns a replacement for the body and a function for http.Request.GetBody.
+func (mi *MediaInfo) UploadRequest(reqHeaders http.Header, body io.Reader) (newBody io.Reader, getBody func() (io.ReadCloser, error), cleanup func()) {
+	cleanup = func() {}
+	if mi == nil {
+		return body, nil, cleanup
+	}
+	var media io.Reader
+	if mi.media != nil {
+		// This only happens when the caller has turned off chunking. In that
+		// case, we write all of media in a single non-retryable request.
+		media = mi.media
+	} else if mi.singleChunk {
+		// The data fits in a single chunk, which has now been read into the MediaBuffer.
+		// We obtain that chunk so we can write it in a single request. The request can
+		// be retried because the data is stored in the MediaBuffer.
+		media, _, _, _ = mi.buffer.Chunk()
+	}
+	if media != nil {
+		fb := readerFunc(body)
+		fm := readerFunc(media)
+		combined, ctype := CombineBodyMedia(body, "application/json", media, mi.mType)
+		if fb != nil && fm != nil {
+			getBody = func() (io.ReadCloser, error) {
+				rb := ioutil.NopCloser(fb())
+				rm := ioutil.NopCloser(fm())
+				r, _ := CombineBodyMedia(rb, "application/json", rm, mi.mType)
+				return r, nil
+			}
+		}
+		cleanup = func() { combined.Close() }
+		reqHeaders.Set("Content-Type", ctype)
+		body = combined
+	}
+	if mi.buffer != nil && mi.mType != "" && !mi.singleChunk {
+		reqHeaders.Set("X-Upload-Content-Type", mi.mType)
+	}
+	return body, getBody, cleanup
+}
+
+// readerFunc returns a function that always returns an io.Reader that has the same
+// contents as r, provided that can be done without consuming r. Otherwise, it
+// returns nil.
+// See http.NewRequest (in net/http/request.go).
+func readerFunc(r io.Reader) func() io.Reader {
+	switch r := r.(type) {
+	case *bytes.Buffer:
+		buf := r.Bytes()
+		return func() io.Reader { return bytes.NewReader(buf) }
+	case *bytes.Reader:
+		snapshot := *r
+		return func() io.Reader { r := snapshot; return &r }
+	case *strings.Reader:
+		snapshot := *r
+		return func() io.Reader { r := snapshot; return &r }
+	default:
+		return nil
+	}
+}
+
+// ResumableUpload returns an appropriately configured ResumableUpload value if the
+// upload is resumable, or nil otherwise.
+func (mi *MediaInfo) ResumableUpload(locURI string) *ResumableUpload {
+	if mi == nil || mi.singleChunk {
+		return nil
+	}
+	return &ResumableUpload{
+		URI:       locURI,
+		Media:     mi.buffer,
+		MediaType: mi.mType,
+		Callback: func(curr int64) {
+			if mi.progressUpdater != nil {
+				mi.progressUpdater(curr, mi.size)
+			}
+		},
+	}
+}
+
+// SetGetBody sets the GetBody field of req to f.
+func SetGetBody(req *http.Request, f func() (io.ReadCloser, error)) {
+	req.GetBody = f
+}