Merge pull request #442 from Lambels/bitly

Add Bitly provider.

providers/bitly/bitly.go

@@ -0,0 +1,171 @@
+// Package bitly implements the OAuth2 protocol for authenticating users through Bitly.
+// This package can be used as a reference implementation of an OAuth2 provider for Goth.
+package bitly
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"net/http"
+
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+)
+
+const (
+	authEndpoint    string = "https://bitly.com/oauth/authorize"
+	tokenEndpoint   string = "https://api-ssl.bitly.com/oauth/access_token"
+	profileEndpoint string = "https://api-ssl.bitly.com/v4/user"
+)
+
+// New creates a new Bitly provider and sets up important connection details.
+// You should always call `bitly.New` to get a new provider. Never try to
+// create one manually.
+func New(clientKey, secret, callbackURL string, scopes ...string) *Provider {
+	p := &Provider{
+		ClientKey:   clientKey,
+		Secret:      secret,
+		CallbackURL: callbackURL,
+	}
+	p.newConfig(scopes)
+	return p
+}
+
+// Provider is the implementation of `goth.Provider` for accessing Bitly.
+type Provider struct {
+	ClientKey    string
+	Secret       string
+	CallbackURL  string
+	HTTPClient   *http.Client
+	config       *oauth2.Config
+	providerName string
+}
+
+// Ensure `bitly.Provider` implements `goth.Provider`.
+var _ goth.Provider = &Provider{}
+
+// Name is the name used to retrieve this provider later.
+func (p *Provider) Name() string {
+	return p.providerName
+}
+
+// SetName is to update the name of the provider (needed in case of multiple providers of 1 type).
+func (p *Provider) SetName(name string) {
+	p.providerName = name
+}
+
+func (p *Provider) Client() *http.Client {
+	return goth.HTTPClientWithFallBack(p.HTTPClient)
+}
+
+// Debug is a no-op for the bitly package.
+func (p *Provider) Debug(debug bool) {}
+
+// BeginAuth asks Bitly for an authentication end-point.
+func (p *Provider) BeginAuth(state string) (goth.Session, error) {
+	url := p.config.AuthCodeURL(state)
+	session := &Session{
+		AuthURL: url,
+	}
+	return session, nil
+}
+
+// FetchUser will go to Bitly and access basic information about the user.
+func (p *Provider) FetchUser(session goth.Session) (goth.User, error) {
+	s := session.(*Session)
+	u := goth.User{
+		Provider:    p.Name(),
+		AccessToken: s.AccessToken,
+	}
+
+	if u.AccessToken == "" {
+		return u, fmt.Errorf("%s cannot get user information without accessToken", p.providerName)
+	}
+
+	req, err := http.NewRequest("GET", profileEndpoint, nil)
+	if err != nil {
+		return u, err
+	}
+	req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", u.AccessToken))
+
+	resp, err := p.Client().Do(req)
+	if err != nil {
+		return u, fmt.Errorf("%s responded with a %d trying to fetch user information", p.providerName, resp.StatusCode)
+	}
+	defer resp.Body.Close()
+
+	buf, err := ioutil.ReadAll(resp.Body)
+	if err != nil {
+		return u, err
+	}
+
+	if err := json.NewDecoder(bytes.NewReader(buf)).Decode(&u.RawData); err != nil {
+		return u, err
+	}
+
+	return u, userFromReader(bytes.NewReader(buf), &u)
+}
+
+// RefreshToken refresh token is not provided by bitly.
+func (p *Provider) RefreshToken(refreshToken string) (*oauth2.Token, error) {
+	return nil, errors.New("Refresh token is not provided by bitly")
+}
+
+// RefreshTokenAvailable refresh token is not provided by bitly.
+func (p *Provider) RefreshTokenAvailable() bool {
+	return false
+}
+
+func (p *Provider) newConfig(scopes []string) {
+	conf := &oauth2.Config{
+		ClientID:     p.ClientKey,
+		ClientSecret: p.Secret,
+		RedirectURL:  p.CallbackURL,
+		Endpoint: oauth2.Endpoint{
+			AuthURL:  authEndpoint,
+			TokenURL: tokenEndpoint,
+		},
+		Scopes: make([]string, 0),
+	}
+
+	conf.Scopes = append(conf.Scopes, scopes...)
+
+	p.config = conf
+}
+
+func userFromReader(reader io.Reader, user *goth.User) (err error) {
+	u := struct {
+		Login  string `json:"login"`
+		Name   string `json:"name"`
+		Emails []struct {
+			Email      string `json:"email"`
+			IsPrimary  bool   `json:"is_primary"`
+			IsVerified bool   `json:"is_verified"`
+		} `json:"emails"`
+	}{}
+	if err := json.NewDecoder(reader).Decode(&u); err != nil {
+		return err
+	}
+
+	user.Name = u.Name
+	user.NickName = u.Login
+	user.Email, err = getEmail(u.Emails)
+	return err
+}
+
+func getEmail(emails []struct {
+	Email      string `json:"email"`
+	IsPrimary  bool   `json:"is_primary"`
+	IsVerified bool   `json:"is_verified"`
+}) (string, error) {
+	for _, email := range emails {
+		if email.IsPrimary && email.IsVerified {
+			return email.Email, nil
+		}
+	}
+
+	return "", fmt.Errorf("The user does not have a verified, primary email address on Bitly")
+}

providers/bitly/bitly_test.go

@@ -0,0 +1,52 @@
+package bitly_test
+
+import (
+	"fmt"
+	"net/url"
+	"testing"
+
+	"github.com/markbates/goth/providers/bitly"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_New(t *testing.T) {
+	t.Parallel()
+	a := assert.New(t)
+
+	p := bitlyProvider()
+	a.Equal(p.ClientKey, "bitly_client_id")
+	a.Equal(p.Secret, "bitly_client_secret")
+	a.Equal(p.CallbackURL, "/foo")
+}
+
+func Test_BeginAuth(t *testing.T) {
+	t.Parallel()
+	a := assert.New(t)
+
+	p := bitlyProvider()
+	s, err := p.BeginAuth("state")
+	s1 := s.(*bitly.Session)
+
+	a.NoError(err)
+	a.Contains(s1.AuthURL, "https://bitly.com/oauth/authorize")
+	a.Contains(s1.AuthURL, fmt.Sprintf("client_id=%s", p.ClientKey))
+	a.Contains(s1.AuthURL, "state=state")
+	a.Contains(s1.AuthURL, fmt.Sprintf("redirect_uri=%s", url.QueryEscape(p.CallbackURL)))
+}
+
+func Test_SessionFromJSON(t *testing.T) {
+	t.Parallel()
+	a := assert.New(t)
+
+	p := bitlyProvider()
+	s, err := p.UnmarshalSession(`{"AuthURL":"https://bitly.com/oauth/authorize","AccessToken":"access_token"}`)
+	s1 := s.(*bitly.Session)
+
+	a.NoError(err)
+	a.Equal(s1.AuthURL, "https://bitly.com/oauth/authorize")
+	a.Equal(s1.AccessToken, "access_token")
+}
+
+func bitlyProvider() *bitly.Provider {
+	return bitly.New("bitly_client_id", "bitly_client_secret", "/foo")
+}

providers/bitly/session.go

@@ -0,0 +1,59 @@
+package bitly
+
+import (
+	"encoding/json"
+	"errors"
+	"strings"
+
+	"github.com/markbates/goth"
+)
+
+// Session stores data during the auth process with Bitly.
+type Session struct {
+	AuthURL     string
+	AccessToken string
+}
+
+// Ensure `bitly.Session` implements `goth.Session`.
+var _ goth.Session = &Session{}
+
+// GetAuthURL will return the URL set by calling the `BeginAuth` function on the Bitly provider.
+func (s Session) GetAuthURL() (string, error) {
+	if s.AuthURL == "" {
+		return "", errors.New(goth.NoAuthUrlErrorMessage)
+	}
+	return s.AuthURL, nil
+}
+
+// Authorize the session with Bitly and return the access token to be stored for future use.
+func (s *Session) Authorize(provider goth.Provider, params goth.Params) (string, error) {
+	p := provider.(*Provider)
+	token, err := p.config.Exchange(goth.ContextForClient(p.Client()), params.Get("code"))
+	if err != nil {
+		return "", err
+	}
+
+	if !token.Valid() {
+		return "", errors.New("Invalid token received from provider")
+	}
+
+	s.AccessToken = token.AccessToken
+	return token.AccessToken, err
+}
+
+// Marshal the session into a string.
+func (s Session) Marshal() string {
+	b, _ := json.Marshal(s)
+	return string(b)
+}
+
+func (s Session) String() string {
+	return s.Marshal()
+}
+
+// UnmarshalSession will unmarshal a JSON string into a session.
+func (p *Provider) UnmarshalSession(data string) (goth.Session, error) {
+	s := &Session{}
+	err := json.NewDecoder(strings.NewReader(data)).Decode(s)
+	return s, err
+}

providers/bitly/session_test.go

@@ -0,0 +1,33 @@
+package bitly_test
+
+import (
+	"testing"
+
+	"github.com/markbates/goth/providers/bitly"
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_GetAuthURL(t *testing.T) {
+	t.Parallel()
+	a := assert.New(t)
+
+	s := &bitly.Session{}
+
+	_, err := s.GetAuthURL()
+	a.Error(err)
+
+	s.AuthURL = "/bar"
+	url, _ := s.GetAuthURL()
+	a.Equal(url, "/bar")
+}
+
+func Test_ToJSON(t *testing.T) {
+	t.Parallel()
+	a := assert.New(t)
+
+	s := &bitly.Session{
+		AuthURL:     "https://bitly.com/oauth/authorize",
+		AccessToken: "access_token",
+	}
+	a.Equal(s.Marshal(), `{"AuthURL":"https://bitly.com/oauth/authorize","AccessToken":"access_token"}`)
+}