Enable admin to search by email (#2888)

models/user.go

@@ -1277,16 +1277,21 @@ type SearchUserOptions struct {
 	Page          int
 	PageSize      int // Can be smaller than or equal to setting.UI.ExplorePagingNum
 	IsActive      util.OptionalBool
+	SearchByEmail bool // Search by email as well as username/full name
 }
 
 func (opts *SearchUserOptions) toConds() builder.Cond {
 	var cond builder.Cond = builder.Eq{"type": opts.Type}
 	if len(opts.Keyword) > 0 {
 		lowerKeyword := strings.ToLower(opts.Keyword)
-		cond = cond.And(builder.Or(
+		keywordCond := builder.Or(
 			builder.Like{"lower_name", lowerKeyword},
 			builder.Like{"LOWER(full_name)", lowerKeyword},
-		))
+		)
+		if opts.SearchByEmail {
+			keywordCond = keywordCond.Or(builder.Like{"LOWER(email)", lowerKeyword})
+		}
+		cond = cond.And(keywordCond)
 	}
 
 	if !opts.IsActive.IsNone() {

routers/admin/users.go

@@ -33,6 +33,7 @@ func Users(ctx *context.Context) {
 	routers.RenderUserSearch(ctx, &models.SearchUserOptions{
 		Type:          models.UserTypeIndividual,
 		PageSize:      setting.UI.Admin.UserPagingNum,
+		SearchByEmail: true,
 	}, tplUsers)
 }