Merge master into breakout_swarm

Signed-off-by: Alex Ellis <alexellis2@gmail.com>

gateway/vendor/github.com/docker/distribution/testutil/handler.go

@@ -0,0 +1,148 @@
+package testutil
+
+import (
+	"bytes"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"sort"
+	"strings"
+)
+
+// RequestResponseMap is an ordered mapping from Requests to Responses
+type RequestResponseMap []RequestResponseMapping
+
+// RequestResponseMapping defines a Response to be sent in response to a given
+// Request
+type RequestResponseMapping struct {
+	Request  Request
+	Response Response
+}
+
+// Request is a simplified http.Request object
+type Request struct {
+	// Method is the http method of the request, for example GET
+	Method string
+
+	// Route is the http route of this request
+	Route string
+
+	// QueryParams are the query parameters of this request
+	QueryParams map[string][]string
+
+	// Body is the byte contents of the http request
+	Body []byte
+
+	// Headers are the header for this request
+	Headers http.Header
+}
+
+func (r Request) String() string {
+	queryString := ""
+	if len(r.QueryParams) > 0 {
+		keys := make([]string, 0, len(r.QueryParams))
+		queryParts := make([]string, 0, len(r.QueryParams))
+		for k := range r.QueryParams {
+			keys = append(keys, k)
+		}
+		sort.Strings(keys)
+		for _, k := range keys {
+			for _, val := range r.QueryParams[k] {
+				queryParts = append(queryParts, fmt.Sprintf("%s=%s", k, url.QueryEscape(val)))
+			}
+		}
+		queryString = "?" + strings.Join(queryParts, "&")
+	}
+	var headers []string
+	if len(r.Headers) > 0 {
+		var headerKeys []string
+		for k := range r.Headers {
+			headerKeys = append(headerKeys, k)
+		}
+		sort.Strings(headerKeys)
+
+		for _, k := range headerKeys {
+			for _, val := range r.Headers[k] {
+				headers = append(headers, fmt.Sprintf("%s:%s", k, val))
+			}
+		}
+
+	}
+	return fmt.Sprintf("%s %s%s\n%s\n%s", r.Method, r.Route, queryString, headers, r.Body)
+}
+
+// Response is a simplified http.Response object
+type Response struct {
+	// Statuscode is the http status code of the Response
+	StatusCode int
+
+	// Headers are the http headers of this Response
+	Headers http.Header
+
+	// Body is the response body
+	Body []byte
+}
+
+// testHandler is an http.Handler with a defined mapping from Request to an
+// ordered list of Response objects
+type testHandler struct {
+	responseMap map[string][]Response
+}
+
+// NewHandler returns a new test handler that responds to defined requests
+// with specified responses
+// Each time a Request is received, the next Response is returned in the
+// mapping, until no Responses are defined, at which point a 404 is sent back
+func NewHandler(requestResponseMap RequestResponseMap) http.Handler {
+	responseMap := make(map[string][]Response)
+	for _, mapping := range requestResponseMap {
+		responses, ok := responseMap[mapping.Request.String()]
+		if ok {
+			responseMap[mapping.Request.String()] = append(responses, mapping.Response)
+		} else {
+			responseMap[mapping.Request.String()] = []Response{mapping.Response}
+		}
+	}
+	return &testHandler{responseMap: responseMap}
+}
+
+func (app *testHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	defer r.Body.Close()
+
+	requestBody, _ := ioutil.ReadAll(r.Body)
+	request := Request{
+		Method:      r.Method,
+		Route:       r.URL.Path,
+		QueryParams: r.URL.Query(),
+		Body:        requestBody,
+		Headers:     make(map[string][]string),
+	}
+
+	// Add headers of interest here
+	for k, v := range r.Header {
+		if k == "If-None-Match" {
+			request.Headers[k] = v
+		}
+	}
+
+	responses, ok := app.responseMap[request.String()]
+
+	if !ok || len(responses) == 0 {
+		http.NotFound(w, r)
+		return
+	}
+
+	response := responses[0]
+	app.responseMap[request.String()] = responses[1:]
+
+	responseHeader := w.Header()
+	for k, v := range response.Headers {
+		responseHeader[k] = v
+	}
+
+	w.WriteHeader(response.StatusCode)
+
+	io.Copy(w, bytes.NewReader(response.Body))
+}