Github provider: use login as user

- Save both user and email in session state:
    Encoding/decoding methods save both email and user
    field in session state, for use cases when User is not derived from
    email's local-parth, like for GitHub provider.

    For retrocompatibility, if no user is obtained by the provider,
    (e.g. User is an empty string) the encoding/decoding methods fall back
    to the previous behavior and use the email's local-part

    Updated also related tests and added two more tests to show behavior
    when session contains a non-empty user value.

- Added first basic GitHub provider tests

- Added GetUserName method to Provider interface
    The new GetUserName method is intended to return the User
    value when this is not the email's local-part.

    Added also the default implementation to provider_default.go

- Added call to GetUserName in redeemCode

    the new GetUserName method is used in redeemCode
    to get SessionState User value.

    For backward compatibility, if GetUserName error is
    "not implemented", the error is ignored.

- Added GetUserName method and tests to github provider.

oauthproxy.go

@@ -244,6 +244,13 @@ func (p *OAuthProxy) redeemCode(host, code string) (s *providers.SessionState, e
 	if s.Email == "" {
 		s.Email, err = p.provider.GetEmailAddress(s)
 	}
+
+	if s.User == "" {
+		s.User, err = p.provider.GetUserName(s)
+		if err != nil && err.Error() == "not implemented" {
+			err = nil
+		}
+	}
 	return
 }
 

providers/github.go

@@ -218,10 +218,10 @@ func (p *GitHubProvider) GetEmailAddress(s *SessionState) (string, error) {
 	if resp.StatusCode != 200 {
 		return "", fmt.Errorf("got %d from %q %s",
 			resp.StatusCode, endpoint.String(), body)
-	} else {
-		log.Printf("got %d from %q %s", resp.StatusCode, endpoint.String(), body)
 	}
 
+	log.Printf("got %d from %q %s", resp.StatusCode, endpoint.String(), body)
+
 	if err := json.Unmarshal(body, &emails); err != nil {
 		return "", fmt.Errorf("%s unmarshaling %s", err, body)
 	}
@@ -234,3 +234,46 @@ func (p *GitHubProvider) GetEmailAddress(s *SessionState) (string, error) {
 
 	return "", nil
 }
+
+func (p *GitHubProvider) GetUserName(s *SessionState) (string, error) {
+	var user struct {
+		Login string `json:"login"`
+		Email string `json:"email"`
+	}
+
+	endpoint := &url.URL{
+		Scheme: p.ValidateURL.Scheme,
+		Host:   p.ValidateURL.Host,
+		Path:   path.Join(p.ValidateURL.Path, "/user"),
+	}
+
+	req, err := http.NewRequest("GET", endpoint.String(), nil)
+	if err != nil {
+		return "", fmt.Errorf("could not create new GET request: %v", err)
+	}
+
+	req.Header.Set("Authorization", fmt.Sprintf("token %s", s.AccessToken))
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return "", err
+	}
+
+	body, err := ioutil.ReadAll(resp.Body)
+	defer resp.Body.Close()
+	if err != nil {
+		return "", err
+	}
+
+	if resp.StatusCode != 200 {
+		return "", fmt.Errorf("got %d from %q %s",
+			resp.StatusCode, endpoint.String(), body)
+	}
+
+	log.Printf("got %d from %q %s", resp.StatusCode, endpoint.String(), body)
+
+	if err := json.Unmarshal(body, &user); err != nil {
+		return "", fmt.Errorf("%s unmarshaling %s", err, body)
+	}
+
+	return user.Login, nil
+}

providers/github_test.go

@@ -0,0 +1,146 @@
+package providers
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func testGitHubProvider(hostname string) *GitHubProvider {
+	p := NewGitHubProvider(
+		&ProviderData{
+			ProviderName: "",
+			LoginURL:     &url.URL{},
+			RedeemURL:    &url.URL{},
+			ProfileURL:   &url.URL{},
+			ValidateURL:  &url.URL{},
+			Scope:        ""})
+	if hostname != "" {
+		updateURL(p.Data().LoginURL, hostname)
+		updateURL(p.Data().RedeemURL, hostname)
+		updateURL(p.Data().ProfileURL, hostname)
+		updateURL(p.Data().ValidateURL, hostname)
+	}
+	return p
+}
+
+func testGitHubBackend(payload string) *httptest.Server {
+	pathToQueryMap := map[string]string{
+		"/user":        "",
+		"/user/emails": "",
+	}
+
+	return httptest.NewServer(http.HandlerFunc(
+		func(w http.ResponseWriter, r *http.Request) {
+			url := r.URL
+			query, ok := pathToQueryMap[url.Path]
+			if !ok {
+				w.WriteHeader(404)
+			} else if url.RawQuery != query {
+				w.WriteHeader(404)
+			} else {
+				w.WriteHeader(200)
+				w.Write([]byte(payload))
+			}
+		}))
+}
+
+func TestGitHubProviderDefaults(t *testing.T) {
+	p := testGitHubProvider("")
+	assert.NotEqual(t, nil, p)
+	assert.Equal(t, "GitHub", p.Data().ProviderName)
+	assert.Equal(t, "https://github.com/login/oauth/authorize",
+		p.Data().LoginURL.String())
+	assert.Equal(t, "https://github.com/login/oauth/access_token",
+		p.Data().RedeemURL.String())
+	assert.Equal(t, "https://api.github.com/",
+		p.Data().ValidateURL.String())
+	assert.Equal(t, "user:email", p.Data().Scope)
+}
+
+func TestGitHubProviderOverrides(t *testing.T) {
+	p := NewGitHubProvider(
+		&ProviderData{
+			LoginURL: &url.URL{
+				Scheme: "https",
+				Host:   "example.com",
+				Path:   "/login/oauth/authorize"},
+			RedeemURL: &url.URL{
+				Scheme: "https",
+				Host:   "example.com",
+				Path:   "/login/oauth/access_token"},
+			ValidateURL: &url.URL{
+				Scheme: "https",
+				Host:   "api.example.com",
+				Path:   "/"},
+			Scope: "profile"})
+	assert.NotEqual(t, nil, p)
+	assert.Equal(t, "GitHub", p.Data().ProviderName)
+	assert.Equal(t, "https://example.com/login/oauth/authorize",
+		p.Data().LoginURL.String())
+	assert.Equal(t, "https://example.com/login/oauth/access_token",
+		p.Data().RedeemURL.String())
+	assert.Equal(t, "https://api.example.com/",
+		p.Data().ValidateURL.String())
+	assert.Equal(t, "profile", p.Data().Scope)
+}
+
+func TestGitHubProviderGetEmailAddress(t *testing.T) {
+	b := testGitHubBackend(`[ {"email": "[email protected]", "primary": true} ]`)
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitHubProvider(bURL.Host)
+
+	session := &SessionState{AccessToken: "imaginary_access_token"}
+	email, err := p.GetEmailAddress(session)
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "[email protected]", email)
+}
+
+// Note that trying to trigger the "failed building request" case is not
+// practical, since the only way it can fail is if the URL fails to parse.
+func TestGitHubProviderGetEmailAddressFailedRequest(t *testing.T) {
+	b := testGitHubBackend("unused payload")
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitHubProvider(bURL.Host)
+
+	// We'll trigger a request failure by using an unexpected access
+	// token. Alternatively, we could allow the parsing of the payload as
+	// JSON to fail.
+	session := &SessionState{AccessToken: "unexpected_access_token"}
+	email, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
+	assert.Equal(t, "", email)
+}
+
+func TestGitHubProviderGetEmailAddressEmailNotPresentInPayload(t *testing.T) {
+	b := testGitHubBackend("{\"foo\": \"bar\"}")
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitHubProvider(bURL.Host)
+
+	session := &SessionState{AccessToken: "imaginary_access_token"}
+	email, err := p.GetEmailAddress(session)
+	assert.NotEqual(t, nil, err)
+	assert.Equal(t, "", email)
+}
+
+func TestGitHubProviderGetUserName(t *testing.T) {
+	b := testGitHubBackend(`{"email": "[email protected]", "login": "mbland"}`)
+	defer b.Close()
+
+	bURL, _ := url.Parse(b.URL)
+	p := testGitHubProvider(bURL.Host)
+
+	session := &SessionState{AccessToken: "imaginary_access_token"}
+	email, err := p.GetUserName(session)
+	assert.Equal(t, nil, err)
+	assert.Equal(t, "mbland", email)
+}

providers/provider_default.go

@@ -106,6 +106,11 @@ func (p *ProviderData) GetEmailAddress(s *SessionState) (string, error) {
 	return "", errors.New("not implemented")
 }
 
+// GetUserName returns the Account username
+func (p *ProviderData) GetUserName(s *SessionState) (string, error) {
+	return "", errors.New("not implemented")
+}
+
 // ValidateGroup validates that the provided email exists in the configured provider
 // email group(s).
 func (p *ProviderData) ValidateGroup(email string) bool {

providers/providers.go

@@ -7,6 +7,7 @@ import (
 type Provider interface {
 	Data() *ProviderData
 	GetEmailAddress(*SessionState) (string, error)
+	GetUserName(*SessionState) (string, error)
 	Redeem(string, string) (*SessionState, error)
 	ValidateGroup(string) bool
 	ValidateSessionState(*SessionState) bool

providers/session_state.go

@@ -25,7 +25,7 @@ func (s *SessionState) IsExpired() bool {
 }
 
 func (s *SessionState) String() string {
-	o := fmt.Sprintf("Session{%s", s.userOrEmail())
+	o := fmt.Sprintf("Session{%s", s.accountInfo())
 	if s.AccessToken != "" {
 		o += " token:true"
 	}
@@ -40,17 +40,13 @@ func (s *SessionState) String() string {
 
 func (s *SessionState) EncodeSessionState(c *cookie.Cipher) (string, error) {
 	if c == nil || s.AccessToken == "" {
-		return s.userOrEmail(), nil
+		return s.accountInfo(), nil
 	}
 	return s.EncryptedString(c)
 }
 
-func (s *SessionState) userOrEmail() string {
-	u := s.User
-	if s.Email != "" {
-		u = s.Email
-	}
-	return u
+func (s *SessionState) accountInfo() string {
+	return fmt.Sprintf("email:%s user:%s", s.Email, s.User)
 }
 
 func (s *SessionState) EncryptedString(c *cookie.Cipher) (string, error) {
@@ -60,56 +56,64 @@ func (s *SessionState) EncryptedString(c *cookie.Cipher) (string, error) {
 	}
 	a := s.AccessToken
 	if a != "" {
-		a, err = c.Encrypt(a)
-		if err != nil {
+		if a, err = c.Encrypt(a); err != nil {
 			return "", err
 		}
 	}
 	r := s.RefreshToken
 	if r != "" {
-		r, err = c.Encrypt(r)
-		if err != nil {
+		if r, err = c.Encrypt(r); err != nil {
 			return "", err
 		}
 	}
-	return fmt.Sprintf("%s|%s|%d|%s", s.userOrEmail(), a, s.ExpiresOn.Unix(), r), nil
+	return fmt.Sprintf("%s|%s|%d|%s", s.accountInfo(), a, s.ExpiresOn.Unix(), r), nil
+}
+
+func decodeSessionStatePlain(v string) (s *SessionState, err error) {
+	chunks := strings.Split(v, " ")
+	if len(chunks) != 2 {
+		return nil, fmt.Errorf("could not decode session state: expected 2 chunks got %d", len(chunks))
+	}
+
+	email := strings.TrimPrefix(chunks[0], "email:")
+	user := strings.TrimPrefix(chunks[1], "user:")
+	if user == "" {
+		user = strings.Split(email, "@")[0]
+	}
+
+	return &SessionState{User: user, Email: email}, nil
 }
 
 func DecodeSessionState(v string, c *cookie.Cipher) (s *SessionState, err error) {
-	chunks := strings.Split(v, "|")
-	if len(chunks) == 1 {
-		if strings.Contains(chunks[0], "@") {
-			u := strings.Split(v, "@")[0]
-			return &SessionState{Email: v, User: u}, nil
-		}
-		return &SessionState{User: v}, nil
+	if c == nil {
+		return decodeSessionStatePlain(v)
 	}
 
+	chunks := strings.Split(v, "|")
 	if len(chunks) != 4 {
 		err = fmt.Errorf("invalid number of fields (got %d expected 4)", len(chunks))
 		return
 	}
 
-	s = &SessionState{}
-	if c != nil && chunks[1] != "" {
-		s.AccessToken, err = c.Decrypt(chunks[1])
-		if err != nil {
+	sessionState, err := decodeSessionStatePlain(chunks[0])
+	if err != nil {
+		return nil, err
+	}
+
+	if chunks[1] != "" {
+		if sessionState.AccessToken, err = c.Decrypt(chunks[1]); err != nil {
 			return nil, err
 		}
 	}
-	if c != nil && chunks[3] != "" {
-		s.RefreshToken, err = c.Decrypt(chunks[3])
-		if err != nil {
+
+	ts, _ := strconv.Atoi(chunks[2])
+	sessionState.ExpiresOn = time.Unix(int64(ts), 0)
+
+	if chunks[3] != "" {
+		if sessionState.RefreshToken, err = c.Decrypt(chunks[3]); err != nil {
 			return nil, err
 		}
 	}
-	if u := chunks[0]; strings.Contains(u, "@") {
-		s.Email = u
-		s.User = strings.Split(u, "@")[0]
-	} else {
-		s.User = u
-	}
-	ts, _ := strconv.Atoi(chunks[2])
-	s.ExpiresOn = time.Unix(int64(ts), 0)
-	return
+
+	return sessionState, nil
 }