wip

internal/service/oauth_service.go

@@ -0,0 +1,78 @@
+package service
+
+import (
+	"context"
+	"crypto/tls"
+	"net/http"
+	"time"
+
+	"github.com/steveiliop56/tinyauth/internal/config"
+	"golang.org/x/oauth2"
+)
+
+type UserinfoExtractor func(client *http.Client, url string) (config.Claims, error)
+
+type OAuthService struct {
+	serviceCfg        config.OAuthServiceConfig
+	config            *oauth2.Config
+	ctx               context.Context
+	userinfoExtractor UserinfoExtractor
+}
+
+func NewOAuthService(config config.OAuthServiceConfig) *OAuthService {
+	httpClient := &http.Client{
+		Timeout: 30 * time.Second,
+		Transport: &http.Transport{
+			TLSClientConfig: &tls.Config{
+				InsecureSkipVerify: config.Insecure,
+			},
+		},
+	}
+	ctx := context.Background()
+	ctx = context.WithValue(ctx, oauth2.HTTPClient, httpClient)
+
+	return &OAuthService{
+		serviceCfg: config,
+		config: &oauth2.Config{
+			ClientID:     config.ClientID,
+			ClientSecret: config.ClientSecret,
+			RedirectURL:  config.RedirectURL,
+			Scopes:       config.Scopes,
+			Endpoint: oauth2.Endpoint{
+				AuthURL:  config.AuthURL,
+				TokenURL: config.TokenURL,
+			},
+		},
+		ctx:               ctx,
+		userinfoExtractor: defaultExtractor,
+	}
+}
+
+func (s *OAuthService) WithUserinfoExtractor(extractor UserinfoExtractor) *OAuthService {
+	s.userinfoExtractor = extractor
+	return s
+}
+
+func (s *OAuthService) Name() string {
+	return s.serviceCfg.Name
+}
+
+func (s *OAuthService) NewRandom() string {
+	// The generate verifier function just creates a random string,
+	// so we can use it to generate a random state as well
+	random := oauth2.GenerateVerifier()
+	return random
+}
+
+func (s *OAuthService) GetAuthURL(state string, verifier string) string {
+	return s.config.AuthCodeURL(state, oauth2.AccessTypeOnline, oauth2.S256ChallengeOption(verifier))
+}
+
+func (s *OAuthService) GetToken(code string, verifier string) (*oauth2.Token, error) {
+	return s.config.Exchange(s.ctx, code, oauth2.VerifierOption(verifier))
+}
+
+func (s *OAuthService) GetUserinfo(token *oauth2.Token) (config.Claims, error) {
+	client := oauth2.NewClient(s.ctx, oauth2.StaticTokenSource(token))
+	return s.userinfoExtractor(client, s.serviceCfg.UserinfoURL)
+}