Add reddit provider and session (#523)

* add reddit provider and session

* fix: wechat failing test

providers/reddit/reddit.go

@@ -0,0 +1,136 @@
+package reddit
+
+import (
+	"encoding/json"
+	"fmt"
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+	"io"
+	"net/http"
+	"time"
+)
+
+const (
+	authURL = "https://www.reddit.com/api/v1/authorize"
+)
+
+type Provider struct {
+	providerName string
+	duration     string
+	config       oauth2.Config
+	client       http.Client
+	// TODO: userURL should be a constant
+	userURL string
+}
+
+func New(clientID string, clientSecret string, redirectURI string, duration string, tokenEndpoint string, userURL string, scopes ...string) Provider {
+	return Provider{
+		providerName: "reddit",
+		duration:     duration,
+		config: oauth2.Config{
+			ClientID:     clientID,
+			ClientSecret: clientSecret,
+			Endpoint: oauth2.Endpoint{
+				AuthURL:   authURL,
+				TokenURL:  tokenEndpoint,
+				AuthStyle: 0,
+			},
+			RedirectURL: redirectURI,
+			Scopes:      scopes,
+		},
+		client:  http.Client{},
+		userURL: userURL,
+	}
+}
+
+func (p *Provider) Name() string {
+	return p.providerName
+}
+
+func (p *Provider) SetName(name string) {
+	p.providerName = name
+}
+
+func (p *Provider) UnmarshalSession(s string) (goth.Session, error) {
+	session := &Session{}
+	err := json.Unmarshal([]byte(s), session)
+	if err != nil {
+		return nil, err
+	}
+
+	return session, nil
+}
+
+func (p *Provider) Debug(b bool) {}
+
+func (p *Provider) RefreshToken(refreshToken string) (*oauth2.Token, error) {
+	return nil, nil
+}
+
+func (p *Provider) RefreshTokenAvailable() bool {
+	return true
+}
+
+func (p *Provider) BeginAuth(state string) (goth.Session, error) {
+	authCodeOption := oauth2.SetAuthURLParam("duration", p.duration)
+	return &Session{AuthURL: p.config.AuthCodeURL(state, authCodeOption)}, nil
+}
+
+type redditResponse struct {
+	Id   string `json:"id"`
+	Name string `json:"name"`
+}
+
+func (p *Provider) FetchUser(s goth.Session) (goth.User, error) {
+	session := s.(*Session)
+	request, err := http.NewRequest("GET", p.userURL, nil)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	bearer := "Bearer " + session.AccessToken
+	request.Header.Add("Authorization", bearer)
+
+	res, err := p.client.Do(request)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	defer res.Body.Close()
+
+	if res.StatusCode != http.StatusOK {
+		if res.StatusCode == http.StatusForbidden {
+			return goth.User{}, fmt.Errorf("%s responded with a %s because you did not provide the identity scope which is required to fetch user profile", p.providerName, res.Status)
+		}
+		return goth.User{}, fmt.Errorf("%s responded with a %d trying to fetch user profile", p.providerName, res.StatusCode)
+	}
+
+	bits, err := io.ReadAll(res.Body)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	var r redditResponse
+
+	err = json.Unmarshal(bits, &r)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	gothUser := goth.User{
+		RawData:      nil,
+		Provider:     p.Name(),
+		Name:         r.Name,
+		UserID:       r.Id,
+		AccessToken:  session.AccessToken,
+		RefreshToken: session.RefreshToken,
+		ExpiresAt:    time.Time{},
+	}
+
+	err = json.Unmarshal(bits, &gothUser.RawData)
+	if err != nil {
+		return goth.User{}, err
+	}
+
+	return gothUser, nil
+}

providers/reddit/reddit_test.go

@@ -0,0 +1,88 @@
+package reddit
+
+import (
+	"encoding/json"
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+	"net/http"
+	"net/http/httptest"
+	"reflect"
+	"testing"
+	"time"
+)
+
+var response = redditResponse{
+	Id:   "invader21",
+	Name: "JohnDoe",
+}
+
+func TestProvider(t *testing.T) {
+	t.Run("create a new provider", func(t *testing.T) {
+		got := New("client id", "client secret", "redirect uri", "duration", "example.com", "userURL", "scope1", "scope2", "scope 3")
+		want := Provider{
+			providerName: "reddit",
+			duration:     "duration",
+			config: oauth2.Config{
+				ClientID:     "client id",
+				ClientSecret: "client secret",
+				Endpoint: oauth2.Endpoint{
+					AuthURL:   authURL,
+					TokenURL:  "example.com",
+					AuthStyle: 0,
+				},
+				RedirectURL: "redirect uri",
+				Scopes:      []string{"scope1", "scope2", "scope 3"},
+			},
+			userURL: "userURL",
+		}
+
+		if !reflect.DeepEqual(got, want) {
+			t.Errorf("\033[31;1;4mgot\033[0m %+v, \n\t \033[31;1;4mwant\033[0m %+v", got, want)
+		}
+	})
+
+	t.Run("fetch reddit user that created the given session", func(t *testing.T) {
+		redditServer := httptest.NewServer(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+			b, err := json.Marshal(response)
+			if err != nil {
+				t.Fatal(err)
+			}
+			writer.Header().Add("Content-Type", "application/json")
+			writer.Write(b)
+		}))
+
+		defer redditServer.Close()
+
+		userURL := redditServer.URL
+		p := New("client id", "client secret", "redirect uri", "duration", "example.com", userURL, "scope1", "scope2", "scope 3")
+		s := &Session{
+			AuthURL:      "",
+			AccessToken:  "i am a token",
+			TokenType:    "bearer",
+			RefreshToken: "your refresh token",
+			Expiry:       time.Time{},
+		}
+
+		got, err := p.FetchUser(s)
+		if err != nil {
+			t.Errorf("did not expect an error: %s", err)
+		}
+
+		want := goth.User{
+			RawData: map[string]interface{}{
+				"id":   "invader21",
+				"name": "JohnDoe",
+			},
+			Provider:     "reddit",
+			Name:         "JohnDoe",
+			UserID:       "invader21",
+			AccessToken:  "i am a token",
+			RefreshToken: "your refresh token",
+			ExpiresAt:    time.Time{},
+		}
+
+		if !reflect.DeepEqual(got, want) {
+			t.Errorf("\033[31;1;4mgot\033[0m %+v, \n\t\t \033[31;1;4mwant\033[0m %+v", got, want)
+		}
+	})
+}

providers/reddit/session.go

@@ -0,0 +1,46 @@
+package reddit
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"github.com/markbates/goth"
+	"golang.org/x/oauth2"
+	"time"
+)
+
+type Session struct {
+	AuthURL      string
+	AccessToken  string    `json:"access_token"`
+	TokenType    string    `json:"token_type,omitempty"`
+	RefreshToken string    `json:"refresh_token,omitempty"`
+	Expiry       time.Time `json:"expiry,omitempty"`
+}
+
+func (s *Session) GetAuthURL() (string, error) {
+	return s.AuthURL, nil
+}
+
+func (s *Session) Marshal() string {
+	b, _ := json.Marshal(s)
+	return string(b)
+}
+
+func (s *Session) Authorize(provider goth.Provider, params goth.Params) (string, error) {
+	p := provider.(*Provider)
+	t, err := p.config.Exchange(context.WithValue(context.Background(), oauth2.HTTPClient, p.client), params.Get("code"))
+	if err != nil {
+		return "", err
+	}
+
+	if !t.Valid() {
+		return "", errors.New("invalid token received from provider")
+	}
+
+	s.AccessToken = t.AccessToken
+	s.TokenType = t.TokenType
+	s.RefreshToken = t.RefreshToken
+	s.Expiry = t.Expiry
+
+	return s.AccessToken, nil
+}

providers/reddit/session_test.go

@@ -0,0 +1,122 @@
+package reddit
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+)
+
+var validAuthResponseTestData = struct {
+	AccessToken  string `json:"access_token"`
+	TokenType    string `json:"token_type"`
+	ExpiresIn    int    `json:"expires_in"`
+	Scope        string `json:"scope"`
+	RefreshToken string `json:"refresh_token"`
+}{
+	AccessToken:  "i am a token",
+	TokenType:    "type",
+	ExpiresIn:    120,
+	Scope:        "identity",
+	RefreshToken: "your refresh token",
+}
+
+var invalidAuthResponseTestData = struct {
+	AccessToken  string `json:"access_token"`
+	TokenType    string `json:"token_type"`
+	ExpiresIn    int    `json:"expires_in"`
+	Scope        string `json:"scope"`
+	RefreshToken string `json:"refresh_token"`
+}{
+	AccessToken:  "",
+	TokenType:    "type",
+	ExpiresIn:    120,
+	Scope:        "identity",
+	RefreshToken: "Your refresh token",
+}
+
+func TestSession(t *testing.T) {
+	t.Run("gets the URL for the authentication end-point for the provider", func(t *testing.T) {
+		s := Session{AuthURL: "example.com"}
+		got, err := s.GetAuthURL()
+		if err != nil {
+			t.Fatal("should return a url string")
+		}
+
+		want := "example.com"
+
+		if got != want {
+			t.Errorf("got %q want %q", got, want)
+		}
+	})
+
+	t.Run("generates a string representation of the session", func(t *testing.T) {
+		s := Session{
+			AuthURL: "example",
+		}
+		got := s.Marshal()
+		want := `{"AuthURL":"example","access_token":"","expiry":"0001-01-01T00:00:00Z"}`
+
+		if got != want {
+			t.Errorf("got %q want %q", got, want)
+		}
+	})
+
+	t.Run("return an access token", func(t *testing.T) {
+
+		s := Session{AuthURL: "example.com"}
+		authServer := httptest.NewServer(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+			b, err := json.Marshal(validAuthResponseTestData)
+			if err != nil {
+				writer.WriteHeader(http.StatusInternalServerError)
+				return
+			}
+			writer.Header().Add("Content-Type", "application/json")
+			writer.WriteHeader(http.StatusOK)
+			writer.Write(b)
+		}))
+
+		tokenURL := authServer.URL
+
+		p := New("CLIENT_ID", "CLIENT_SECRET", "URI", "DURATION", tokenURL, "SCOPE_STRING1", "SCOPE_STRING2")
+		u := url.Values{}
+		u.Set("code", "12345678")
+
+		got, err := s.Authorize(&p, u)
+		if err != nil {
+			t.Fatal("did not expect an error: ", err)
+		}
+
+		want := validAuthResponseTestData.AccessToken
+
+		if got != want {
+			t.Errorf("got %q want %q", got, want)
+		}
+	})
+
+	t.Run("validates access token", func(t *testing.T) {
+		s := Session{AuthURL: "example.com"}
+		authServer := httptest.NewServer(http.HandlerFunc(func(writer http.ResponseWriter, request *http.Request) {
+			b, err := json.Marshal(invalidAuthResponseTestData)
+			if err != nil {
+				writer.WriteHeader(http.StatusInternalServerError)
+				return
+			}
+			writer.Header().Add("Content-Type", "application/json")
+			writer.WriteHeader(http.StatusOK)
+			writer.Write(b)
+		}))
+
+		tokenURL := authServer.URL
+
+		p := New("CLIENT_ID", "CLIENT_SECRET", "URI", "DURATION", tokenURL, "SCOPE_STRING1", "SCOPE_STRING2")
+		u := url.Values{}
+		u.Set("code", "12345678")
+
+		_, err := s.Authorize(&p, u)
+		if err == nil {
+			t.Errorf("expected an error but didn't get one")
+		}
+	})
+}