feat(go): improve error message.

pro/auth/azure-ad.go

@@ -79,9 +79,18 @@ func handleAzureCallback(w http.ResponseWriter, r *http.Request) {
 		handleOauthUserSignUpApprovalPending(w)
 		return
 	}
-	// if user exists with provider ID, convert them into email ID
+
 	user, err := logic.GetUser(content.UserPrincipalName)
 	if err == nil {
+		// if user exists, then ensure user's auth type is
+		// oauth before proceeding.
+		if user.AuthType == models.BasicAuth {
+			logger.Log(0, "invalid auth type: basic_auth")
+			handleAuthTypeMismatch(w)
+			return
+		}
+
+		// if user exists with provider ID, convert them into email ID
 		_, err := logic.GetUser(content.Email)
 		if err != nil {
 			user.UserName = content.Email
@@ -91,7 +100,8 @@ func handleAzureCallback(w http.ResponseWriter, r *http.Request) {
 			database.Insert(user.UserName, string(d), database.USERS_TABLE_NAME)
 		}
 	}
-	_, err = logic.GetUser(content.Email)
+
+	user, err = logic.GetUser(content.Email)
 	if err != nil {
 		if database.IsEmptyRecord(err) { // user must not exist, so try to make one
 			if inviteExists {
@@ -127,7 +137,16 @@ func handleAzureCallback(w http.ResponseWriter, r *http.Request) {
 			handleSomethingWentWrong(w)
 			return
 		}
+	} else {
+		// if user exists, then ensure user's auth type is
+		// oauth before proceeding.
+		if user.AuthType == models.BasicAuth {
+			logger.Log(0, "invalid auth type: basic_auth")
+			handleAuthTypeMismatch(w)
+			return
+		}
 	}
+
 	user, err = logic.GetUser(content.Email)
 	if err != nil {
 		handleOauthUserNotFound(w)

pro/auth/error.go

@@ -110,6 +110,9 @@ var somethingwentwrong = fmt.Sprintf(htmlBaseTemplate, `<h2>Something went wrong
 
 var notallowedtosignup = fmt.Sprintf(htmlBaseTemplate, `<h2>Your email is not allowed. Please contact your administrator.</h2>`)
 
+var authTypeMismatch = fmt.Sprintf(htmlBaseTemplate, `<h2>It looks like you already have an account with us using Basic Authentication.</h2>
+<p>To continue, please log in with your existing credentials or reset your password if needed.</p>`)
+
 func handleOauthUserNotFound(response http.ResponseWriter) {
 	response.Header().Set("Content-Type", "text/html; charset=utf-8")
 	response.WriteHeader(http.StatusNotFound)
@@ -157,3 +160,9 @@ func handleSomethingWentWrong(response http.ResponseWriter) {
 	response.WriteHeader(http.StatusInternalServerError)
 	response.Write([]byte(somethingwentwrong))
 }
+
+func handleAuthTypeMismatch(response http.ResponseWriter) {
+	response.Header().Set("Content-Type", "text/html; charset=utf-8")
+	response.WriteHeader(http.StatusBadRequest)
+	response.Write([]byte(authTypeMismatch))
+}

pro/auth/github.go

@@ -82,6 +82,14 @@ func handleGithubCallback(w http.ResponseWriter, r *http.Request) {
 	// if user exists with provider ID, convert them into email ID
 	user, err := logic.GetUser(content.Login)
 	if err == nil {
+		// if user exists, then ensure user's auth type is
+		// oauth before proceeding.
+		if user.AuthType == models.BasicAuth {
+			logger.Log(0, "invalid auth type: basic_auth")
+			handleAuthTypeMismatch(w)
+			return
+		}
+
 		// checks if user exists with email
 		_, err := logic.GetUser(content.Email)
 		if err != nil {

pro/auth/google.go

@@ -80,7 +80,8 @@ func handleGoogleCallback(w http.ResponseWriter, r *http.Request) {
 		handleOauthUserSignUpApprovalPending(w)
 		return
 	}
-	_, err = logic.GetUser(content.Email)
+
+	user, err := logic.GetUser(content.Email)
 	if err != nil {
 		if database.IsEmptyRecord(err) { // user must not exist, so try to make one
 			if inviteExists {
@@ -117,13 +118,23 @@ func handleGoogleCallback(w http.ResponseWriter, r *http.Request) {
 			handleSomethingWentWrong(w)
 			return
 		}
+	} else {
+		// if user exists, then ensure user's auth type is
+		// oauth before proceeding.
+		if user.AuthType == models.BasicAuth {
+			logger.Log(0, "invalid auth type: basic_auth")
+			handleAuthTypeMismatch(w)
+			return
+		}
 	}
-	user, err := logic.GetUser(content.Email)
+
+	user, err = logic.GetUser(content.Email)
 	if err != nil {
 		logger.Log(0, "error fetching user: ", err.Error())
 		handleOauthUserNotFound(w)
 		return
 	}
+
 	userRole, err := logic.GetRole(user.PlatformRoleID)
 	if err != nil {
 		handleSomethingWentWrong(w)

pro/auth/oidc.go

@@ -91,7 +91,8 @@ func handleOIDCCallback(w http.ResponseWriter, r *http.Request) {
 		handleOauthUserSignUpApprovalPending(w)
 		return
 	}
-	_, err = logic.GetUser(content.Email)
+
+	user, err := logic.GetUser(content.Email)
 	if err != nil {
 		if database.IsEmptyRecord(err) { // user must not exist, so try to make one
 			if inviteExists {
@@ -127,8 +128,17 @@ func handleOIDCCallback(w http.ResponseWriter, r *http.Request) {
 			handleSomethingWentWrong(w)
 			return
 		}
+	} else {
+		// if user exists, then ensure user's auth type is
+		// oauth before proceeding.
+		if user.AuthType == models.BasicAuth {
+			logger.Log(0, "invalid auth type: basic_auth")
+			handleAuthTypeMismatch(w)
+			return
+		}
 	}
-	user, err := logic.GetUser(content.Email)
+
+	user, err = logic.GetUser(content.Email)
 	if err != nil {
 		handleOauthUserNotFound(w)
 		return