Refactor authorization challenges to its own package

Split challenges into its own package. Avoids possible
import cycle with challenges from client.

Signed-off-by: Derek McGowan <derek@mcgstyle.net> (github: dmcgowan)

registry/client/auth/challenge/authchallenge_test.go

@@ -0,0 +1,127 @@
+package challenge
+
+import (
+	"fmt"
+	"net/http"
+	"net/url"
+	"strings"
+	"sync"
+	"testing"
+)
+
+func TestAuthChallengeParse(t *testing.T) {
+	header := http.Header{}
+	header.Add("WWW-Authenticate", `Bearer realm="https://auth.example.com/token",service="registry.example.com",other=fun,slashed="he\"\l\lo"`)
+
+	challenges := parseAuthHeader(header)
+	if len(challenges) != 1 {
+		t.Fatalf("Unexpected number of auth challenges: %d, expected 1", len(challenges))
+	}
+	challenge := challenges[0]
+
+	if expected := "bearer"; challenge.Scheme != expected {
+		t.Fatalf("Unexpected scheme: %s, expected: %s", challenge.Scheme, expected)
+	}
+
+	if expected := "https://auth.example.com/token"; challenge.Parameters["realm"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenge.Parameters["realm"], expected)
+	}
+
+	if expected := "registry.example.com"; challenge.Parameters["service"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenge.Parameters["service"], expected)
+	}
+
+	if expected := "fun"; challenge.Parameters["other"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenge.Parameters["other"], expected)
+	}
+
+	if expected := "he\"llo"; challenge.Parameters["slashed"] != expected {
+		t.Fatalf("Unexpected param: %s, expected: %s", challenge.Parameters["slashed"], expected)
+	}
+
+}
+
+func TestAuthChallengeNormalization(t *testing.T) {
+	testAuthChallengeNormalization(t, "reg.EXAMPLE.com")
+	testAuthChallengeNormalization(t, "bɿɒʜɔiɿ-ɿɘƚƨim-ƚol-ɒ-ƨʞnɒʜƚ.com")
+	testAuthChallengeNormalization(t, "reg.example.com:80")
+	testAuthChallengeConcurrent(t, "reg.EXAMPLE.com")
+}
+
+func testAuthChallengeNormalization(t *testing.T, host string) {
+
+	scm := NewSimpleManager()
+
+	url, err := url.Parse(fmt.Sprintf("http://%s/v2/", host))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	resp := &http.Response{
+		Request: &http.Request{
+			URL: url,
+		},
+		Header:     make(http.Header),
+		StatusCode: http.StatusUnauthorized,
+	}
+	resp.Header.Add("WWW-Authenticate", fmt.Sprintf("Bearer realm=\"https://%s/token\",service=\"registry.example.com\"", host))
+
+	err = scm.AddResponse(resp)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	lowered := *url
+	lowered.Host = strings.ToLower(lowered.Host)
+	lowered.Host = canonicalAddr(&lowered)
+	c, err := scm.GetChallenges(lowered)
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(c) == 0 {
+		t.Fatal("Expected challenge for lower-cased-host URL")
+	}
+}
+
+func testAuthChallengeConcurrent(t *testing.T, host string) {
+
+	scm := NewSimpleManager()
+
+	url, err := url.Parse(fmt.Sprintf("http://%s/v2/", host))
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	resp := &http.Response{
+		Request: &http.Request{
+			URL: url,
+		},
+		Header:     make(http.Header),
+		StatusCode: http.StatusUnauthorized,
+	}
+	resp.Header.Add("WWW-Authenticate", fmt.Sprintf("Bearer realm=\"https://%s/token\",service=\"registry.example.com\"", host))
+	var s sync.WaitGroup
+	s.Add(2)
+	go func() {
+		defer s.Done()
+		for i := 0; i < 200; i++ {
+			err = scm.AddResponse(resp)
+			if err != nil {
+				t.Error(err)
+			}
+		}
+	}()
+	go func() {
+		defer s.Done()
+		lowered := *url
+		lowered.Host = strings.ToLower(lowered.Host)
+		for k := 0; k < 200; k++ {
+			_, err := scm.GetChallenges(lowered)
+			if err != nil {
+				t.Error(err)
+			}
+		}
+	}()
+	s.Wait()
+}