implement auth using Auth0

internal/site/login.go

@@ -0,0 +1,86 @@
+package site
+
+import (
+	"fmt"
+	"net/http"
+)
+
+// GET /login
+func (s *Server) loginPage(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+
+	state, err := s.auth.NewState(ctx)
+	if err != nil {
+		http.Error(w, fmt.Sprintf("failed to generate random state: %v", err), http.StatusInternalServerError)
+		return
+	}
+
+	base64EncodedState := fmt.Sprintf("%x", state[:])
+
+	http.Redirect(w, r, s.auth.AuthCodeURL(base64EncodedState), http.StatusTemporaryRedirect)
+}
+
+// POST /login
+func (s *Server) login(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	email := r.FormValue("email")
+	if email == "" {
+		http.Error(w, "no email provided", http.StatusBadRequest)
+		return
+	}
+
+	acct, err := s.accts.GetAccountByEmail(ctx, email)
+	if err != nil {
+		http.Error(w, fmt.Sprintf("failed to create account: %v", err), http.StatusInternalServerError)
+		return
+	}
+
+	//http.Redirect(w, r, fmt.Sprintf("/site/accounts/%d", acct.ID), http.StatusSeeOther)
+	http.Redirect(w, r, fmt.Sprintf("/accounts/%d", acct.ID), http.StatusSeeOther)
+}
+
+// GET /login/callback
+func (s *Server) loginCallback(w http.ResponseWriter, r *http.Request) {
+	ctx := r.Context()
+	q := r.URL.Query()
+
+	// obtain token and profile
+
+	accessToken, expiration, err := s.auth.Exchange(ctx, q.Get("state"), q.Get("code"))
+	if err != nil {
+		http.Error(w, "Failed to exchange an authorization code for a token", http.StatusUnauthorized)
+		return
+	}
+
+	// set access_token cookie and redirect to a reasonable place
+
+	w.Header().Set("Set-Cookie", (&http.Cookie{
+		Name:     "access_token",
+		Value:    accessToken,
+		Path:     "/",
+		Expires:  expiration,
+		MaxAge:   0, // using Expiration instead
+		Secure:   true,
+		SameSite: http.SameSiteStrictMode,
+	}).String())
+
+	http.Redirect(w, r, "/", http.StatusTemporaryRedirect)
+}
+
+// GET /logout
+func (s *Server) logoutPage(w http.ResponseWriter, r *http.Request) {
+	host := r.Header.Get("X-Forwarded-Host")
+	if host == "" {
+		host = r.Host
+	}
+
+	deleteCookieInResponse(w, "access_token")
+
+	if ck, err := r.Cookie("access_token"); err == nil && ck != nil {
+		if err := s.auth.DeleteOAuthTokens(r.Context(), ck.Value); err != nil {
+			fmt.Println("[ERROR] failed to delete auth token:", err)
+		}
+	}
+
+	http.Redirect(w, r, s.auth.GetLogoutURL(host).String(), http.StatusTemporaryRedirect)
+}