Users: Disable users removed from LDAP (#16820)

* Users: add is_disabled column

* Users: disable users removed from LDAP

* Auth: return ErrInvalidCredentials for failed LDAP auth

* User: return isDisabled flag in user search api

* User: mark disabled users at the server admin page

* Chore: refactor according to review

* Auth: prevent disabled user from login

* Auth: re-enable user when it found in ldap

* User: add api endpoint for disabling user

* User: use separate endpoints to disable/enable user

* User: disallow disabling external users

* User: able do disable users from admin UI

* Chore: refactor based on review

* Chore: use more clear error check when disabling user

* Fix login tests

* Tests for disabling user during the LDAP login

* Tests for disable user API

* Tests for login with disabled user

* Remove disable user UI stub

* Sync with latest LDAP refactoring

pkg/models/user_auth.go

@@ -6,6 +6,10 @@ import (
 	"golang.org/x/oauth2"
 )
 
+const (
+	AuthModuleLDAP = "ldap"
+)
+
 type UserAuth struct {
 	Id                int64
 	UserId            int64
@@ -29,6 +33,7 @@ type ExternalUserInfo struct {
 	Groups         []string
 	OrgRoles       map[int64]RoleType
 	IsGrafanaAdmin *bool // This is a pointer to know if we should sync this or not (nil = ignore sync)
+	IsDisabled     bool
 }
 
 // ---------------------
@@ -81,6 +86,12 @@ type GetUserByAuthInfoQuery struct {
 	Result *User
 }
 
+type GetExternalUserInfoByLoginQuery struct {
+	LoginOrEmail string
+
+	Result *ExternalUserInfo
+}
+
 type GetAuthInfoQuery struct {
 	UserId     int64
 	AuthModule string