refactor: unify OAuth providers with i18n support

- Introduce Provider interface pattern for standard OAuth protocols
- Create unified controller/oauth.go with common OAuth logic
- Add OAuthError type for translatable error messages
- Add i18n keys and translations (zh/en) for OAuth messages
- Use common.ApiErrorI18n/ApiSuccessI18n for consistent responses
- Preserve backward compatibility for existing routes and data

oauth/github.go

@@ -0,0 +1,160 @@
+package oauth
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"time"
+
+	"github.com/QuantumNous/new-api/common"
+	"github.com/QuantumNous/new-api/i18n"
+	"github.com/QuantumNous/new-api/logger"
+	"github.com/QuantumNous/new-api/model"
+	"github.com/gin-gonic/gin"
+)
+
+func init() {
+	Register("github", &GitHubProvider{})
+}
+
+// GitHubProvider implements OAuth for GitHub
+type GitHubProvider struct{}
+
+type gitHubOAuthResponse struct {
+	AccessToken string `json:"access_token"`
+	Scope       string `json:"scope"`
+	TokenType   string `json:"token_type"`
+}
+
+type gitHubUser struct {
+	Login string `json:"login"`
+	Name  string `json:"name"`
+	Email string `json:"email"`
+}
+
+func (p *GitHubProvider) GetName() string {
+	return "GitHub"
+}
+
+func (p *GitHubProvider) IsEnabled() bool {
+	return common.GitHubOAuthEnabled
+}
+
+func (p *GitHubProvider) ExchangeToken(ctx context.Context, code string, c *gin.Context) (*OAuthToken, error) {
+	if code == "" {
+		return nil, NewOAuthError(i18n.MsgOAuthInvalidCode, nil)
+	}
+
+	logger.LogDebug(ctx, "[OAuth-GitHub] ExchangeToken: code=%s...", code[:min(len(code), 10)])
+
+	values := map[string]string{
+		"client_id":     common.GitHubClientId,
+		"client_secret": common.GitHubClientSecret,
+		"code":          code,
+	}
+	jsonData, err := json.Marshal(values)
+	if err != nil {
+		return nil, err
+	}
+
+	req, err := http.NewRequestWithContext(ctx, "POST", "https://github.com/login/oauth/access_token", bytes.NewBuffer(jsonData))
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Content-Type", "application/json")
+	req.Header.Set("Accept", "application/json")
+
+	client := http.Client{
+		Timeout: 20 * time.Second,
+	}
+	res, err := client.Do(req)
+	if err != nil {
+		logger.LogError(ctx, fmt.Sprintf("[OAuth-GitHub] ExchangeToken error: %s", err.Error()))
+		return nil, NewOAuthErrorWithRaw(i18n.MsgOAuthConnectFailed, map[string]any{"Provider": "GitHub"}, err.Error())
+	}
+	defer res.Body.Close()
+
+	logger.LogDebug(ctx, "[OAuth-GitHub] ExchangeToken response status: %d", res.StatusCode)
+
+	var oAuthResponse gitHubOAuthResponse
+	err = json.NewDecoder(res.Body).Decode(&oAuthResponse)
+	if err != nil {
+		logger.LogError(ctx, fmt.Sprintf("[OAuth-GitHub] ExchangeToken decode error: %s", err.Error()))
+		return nil, err
+	}
+
+	if oAuthResponse.AccessToken == "" {
+		logger.LogError(ctx, "[OAuth-GitHub] ExchangeToken failed: empty access token")
+		return nil, NewOAuthError(i18n.MsgOAuthTokenFailed, map[string]any{"Provider": "GitHub"})
+	}
+
+	logger.LogDebug(ctx, "[OAuth-GitHub] ExchangeToken success: scope=%s", oAuthResponse.Scope)
+
+	return &OAuthToken{
+		AccessToken: oAuthResponse.AccessToken,
+		TokenType:   oAuthResponse.TokenType,
+		Scope:       oAuthResponse.Scope,
+	}, nil
+}
+
+func (p *GitHubProvider) GetUserInfo(ctx context.Context, token *OAuthToken) (*OAuthUser, error) {
+	logger.LogDebug(ctx, "[OAuth-GitHub] GetUserInfo: fetching user info")
+
+	req, err := http.NewRequestWithContext(ctx, "GET", "https://api.github.com/user", nil)
+	if err != nil {
+		return nil, err
+	}
+	req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token.AccessToken))
+
+	client := http.Client{
+		Timeout: 20 * time.Second,
+	}
+	res, err := client.Do(req)
+	if err != nil {
+		logger.LogError(ctx, fmt.Sprintf("[OAuth-GitHub] GetUserInfo error: %s", err.Error()))
+		return nil, NewOAuthErrorWithRaw(i18n.MsgOAuthConnectFailed, map[string]any{"Provider": "GitHub"}, err.Error())
+	}
+	defer res.Body.Close()
+
+	logger.LogDebug(ctx, "[OAuth-GitHub] GetUserInfo response status: %d", res.StatusCode)
+
+	var githubUser gitHubUser
+	err = json.NewDecoder(res.Body).Decode(&githubUser)
+	if err != nil {
+		logger.LogError(ctx, fmt.Sprintf("[OAuth-GitHub] GetUserInfo decode error: %s", err.Error()))
+		return nil, err
+	}
+
+	if githubUser.Login == "" {
+		logger.LogError(ctx, "[OAuth-GitHub] GetUserInfo failed: empty login field")
+		return nil, NewOAuthError(i18n.MsgOAuthUserInfoEmpty, map[string]any{"Provider": "GitHub"})
+	}
+
+	logger.LogDebug(ctx, "[OAuth-GitHub] GetUserInfo success: login=%s, name=%s, email=%s", githubUser.Login, githubUser.Name, githubUser.Email)
+
+	return &OAuthUser{
+		ProviderUserID: githubUser.Login,
+		Username:       githubUser.Login,
+		DisplayName:    githubUser.Name,
+		Email:          githubUser.Email,
+	}, nil
+}
+
+func (p *GitHubProvider) IsUserIDTaken(providerUserID string) bool {
+	return model.IsGitHubIdAlreadyTaken(providerUserID)
+}
+
+func (p *GitHubProvider) FillUserByProviderID(user *model.User, providerUserID string) error {
+	user.GitHubId = providerUserID
+	return user.FillUserByGitHubId()
+}
+
+func (p *GitHubProvider) SetProviderUserID(user *model.User, providerUserID string) {
+	user.GitHubId = providerUserID
+}
+
+func (p *GitHubProvider) GetProviderPrefix() string {
+	return "github_"
+}