Bump google.golang.org/api

vendor/github.com/google/martian/messageview/messageview.go

@@ -0,0 +1,290 @@
+// Copyright 2015 Google Inc. All rights reserved.
+//
+// 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 messageview provides no-op snapshots for HTTP requests and
+// responses.
+package messageview
+
+import (
+	"bytes"
+	"compress/flate"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/http/httputil"
+	"strings"
+)
+
+// MessageView is a static view of an HTTP request or response.
+type MessageView struct {
+	message       []byte
+	cts           []string
+	chunked       bool
+	skipBody      bool
+	compress      string
+	bodyoffset    int64
+	traileroffset int64
+}
+
+type config struct {
+	decode bool
+}
+
+// Option is a configuration option for a MessageView.
+type Option func(*config)
+
+// Decode sets an option to decode the message body for logging purposes.
+func Decode() Option {
+	return func(c *config) {
+		c.decode = true
+	}
+}
+
+// New returns a new MessageView.
+func New() *MessageView {
+	return &MessageView{}
+}
+
+// SkipBody will skip reading the body when the view is loaded with a request
+// or response.
+func (mv *MessageView) SkipBody(skipBody bool) {
+	mv.skipBody = skipBody
+}
+
+// SkipBodyUnlessContentType will skip reading the body unless the
+// Content-Type matches one in cts.
+func (mv *MessageView) SkipBodyUnlessContentType(cts ...string) {
+	mv.skipBody = true
+	mv.cts = cts
+}
+
+// SnapshotRequest reads the request into the MessageView. If mv.skipBody is false
+// it will also read the body into memory and replace the existing body with
+// the in-memory copy. This method is semantically a no-op.
+func (mv *MessageView) SnapshotRequest(req *http.Request) error {
+	buf := new(bytes.Buffer)
+
+	fmt.Fprintf(buf, "%s %s HTTP/%d.%d\r\n", req.Method,
+		req.URL, req.ProtoMajor, req.ProtoMinor)
+
+	if req.Host != "" {
+		fmt.Fprintf(buf, "Host: %s\r\n", req.Host)
+	}
+
+	if tec := len(req.TransferEncoding); tec > 0 {
+		mv.chunked = req.TransferEncoding[tec-1] == "chunked"
+		fmt.Fprintf(buf, "Transfer-Encoding: %s\r\n", strings.Join(req.TransferEncoding, ", "))
+	}
+	if !mv.chunked && req.ContentLength >= 0 {
+		fmt.Fprintf(buf, "Content-Length: %d\r\n", req.ContentLength)
+	}
+
+	mv.compress = req.Header.Get("Content-Encoding")
+
+	req.Header.WriteSubset(buf, map[string]bool{
+		"Host":              true,
+		"Content-Length":    true,
+		"Transfer-Encoding": true,
+	})
+
+	fmt.Fprint(buf, "\r\n")
+
+	mv.bodyoffset = int64(buf.Len())
+	mv.traileroffset = int64(buf.Len())
+
+	ct := req.Header.Get("Content-Type")
+	if mv.skipBody && !mv.matchContentType(ct) || req.Body == nil {
+		mv.message = buf.Bytes()
+		return nil
+	}
+
+	data, err := ioutil.ReadAll(req.Body)
+	if err != nil {
+		return err
+	}
+	req.Body.Close()
+
+	if mv.chunked {
+		cw := httputil.NewChunkedWriter(buf)
+		cw.Write(data)
+		cw.Close()
+	} else {
+		buf.Write(data)
+	}
+
+	mv.traileroffset = int64(buf.Len())
+
+	req.Body = ioutil.NopCloser(bytes.NewReader(data))
+
+	if req.Trailer != nil {
+		req.Trailer.Write(buf)
+	} else if mv.chunked {
+		fmt.Fprint(buf, "\r\n")
+	}
+
+	mv.message = buf.Bytes()
+
+	return nil
+}
+
+// SnapshotResponse reads the response into the MessageView. If mv.headersOnly
+// is false it will also read the body into memory and replace the existing
+// body with the in-memory copy. This method is semantically a no-op.
+func (mv *MessageView) SnapshotResponse(res *http.Response) error {
+	buf := new(bytes.Buffer)
+
+	fmt.Fprintf(buf, "HTTP/%d.%d %s\r\n", res.ProtoMajor, res.ProtoMinor, res.Status)
+
+	if tec := len(res.TransferEncoding); tec > 0 {
+		mv.chunked = res.TransferEncoding[tec-1] == "chunked"
+		fmt.Fprintf(buf, "Transfer-Encoding: %s\r\n", strings.Join(res.TransferEncoding, ", "))
+	}
+	if !mv.chunked && res.ContentLength >= 0 {
+		fmt.Fprintf(buf, "Content-Length: %d\r\n", res.ContentLength)
+	}
+
+	mv.compress = res.Header.Get("Content-Encoding")
+	// Do not uncompress if we have don't have the full contents.
+	if res.StatusCode == http.StatusNoContent || res.StatusCode == http.StatusPartialContent {
+		mv.compress = ""
+	}
+
+	res.Header.WriteSubset(buf, map[string]bool{
+		"Content-Length":    true,
+		"Transfer-Encoding": true,
+	})
+
+	fmt.Fprint(buf, "\r\n")
+
+	mv.bodyoffset = int64(buf.Len())
+	mv.traileroffset = int64(buf.Len())
+
+	ct := res.Header.Get("Content-Type")
+	if mv.skipBody && !mv.matchContentType(ct) || res.Body == nil {
+		mv.message = buf.Bytes()
+		return nil
+	}
+
+	data, err := ioutil.ReadAll(res.Body)
+	if err != nil {
+		return err
+	}
+	res.Body.Close()
+
+	if mv.chunked {
+		cw := httputil.NewChunkedWriter(buf)
+		cw.Write(data)
+		cw.Close()
+	} else {
+		buf.Write(data)
+	}
+
+	mv.traileroffset = int64(buf.Len())
+
+	res.Body = ioutil.NopCloser(bytes.NewReader(data))
+
+	if res.Trailer != nil {
+		res.Trailer.Write(buf)
+	} else if mv.chunked {
+		fmt.Fprint(buf, "\r\n")
+	}
+
+	mv.message = buf.Bytes()
+
+	return nil
+}
+
+// Reader returns the an io.ReadCloser that reads the full HTTP message.
+func (mv *MessageView) Reader(opts ...Option) (io.ReadCloser, error) {
+	hr := mv.HeaderReader()
+	br, err := mv.BodyReader(opts...)
+	if err != nil {
+		return nil, err
+	}
+	tr := mv.TrailerReader()
+
+	return struct {
+		io.Reader
+		io.Closer
+	}{
+		Reader: io.MultiReader(hr, br, tr),
+		Closer: br,
+	}, nil
+}
+
+// HeaderReader returns an io.Reader that reads the HTTP Status-Line or
+// HTTP Request-Line and headers.
+func (mv *MessageView) HeaderReader() io.Reader {
+	r := bytes.NewReader(mv.message)
+	return io.NewSectionReader(r, 0, mv.bodyoffset)
+}
+
+// BodyReader returns an io.ReadCloser that reads the HTTP request or response
+// body. If mv.skipBody was set the reader will immediately return io.EOF.
+//
+// If the Decode option is passed the body will be unchunked if
+// Transfer-Encoding is set to "chunked", and will decode the following
+// Content-Encodings: gzip, deflate.
+func (mv *MessageView) BodyReader(opts ...Option) (io.ReadCloser, error) {
+	var r io.Reader
+
+	conf := &config{}
+	for _, o := range opts {
+		o(conf)
+	}
+
+	br := bytes.NewReader(mv.message)
+	r = io.NewSectionReader(br, mv.bodyoffset, mv.traileroffset-mv.bodyoffset)
+
+	if !conf.decode {
+		return ioutil.NopCloser(r), nil
+	}
+
+	if mv.chunked {
+		r = httputil.NewChunkedReader(r)
+	}
+	switch mv.compress {
+	case "gzip":
+		gr, err := gzip.NewReader(r)
+		if err != nil {
+			return nil, err
+		}
+		return gr, nil
+	case "deflate":
+		return flate.NewReader(r), nil
+	default:
+		return ioutil.NopCloser(r), nil
+	}
+}
+
+// TrailerReader returns an io.Reader that reads the HTTP request or response
+// trailers, if present.
+func (mv *MessageView) TrailerReader() io.Reader {
+	r := bytes.NewReader(mv.message)
+	end := int64(len(mv.message)) - mv.traileroffset
+
+	return io.NewSectionReader(r, mv.traileroffset, end)
+}
+
+func (mv *MessageView) matchContentType(mct string) bool {
+	for _, ct := range mv.cts {
+		if strings.HasPrefix(mct, ct) {
+			return true
+		}
+	}
+
+	return false
+}