Search: Fixes search limits and adds a page parameter (#16458)

* Search: Fixes search limits and adds a page parameter

This adds a page parameter to search api without adding
any major breaking change.

It does at an api validation error when trying to use
a limit beyond 5000. This is a breaking change. We could
remove this and have it only in the docs and describe that this
is a limit that grafana will apply silently.

Fixes #16049

* Fix: Corrected wrong array slice change

* Docs: minor docs fix

* Search: fixed folder tests

* Fixed: Moved limit to correct inner query

* Search: moving limit check and page check

* Search: limit in handler is no longer needed

pkg/services/sqlstore/search_builder.go

@@ -11,7 +11,8 @@ type SearchBuilder struct {
 	SqlBuilder
 	tags                []string
 	isStarred           bool
-	limit               int
+	limit               int64
+	page                int64
 	signedInUser        *m.SignedInUser
 	whereDashboardIdsIn []int64
 	whereTitle          string
@@ -21,10 +22,21 @@ type SearchBuilder struct {
 	permission          m.PermissionType
 }
 
-func NewSearchBuilder(signedInUser *m.SignedInUser, limit int, permission m.PermissionType) *SearchBuilder {
+func NewSearchBuilder(signedInUser *m.SignedInUser, limit int64, page int64, permission m.PermissionType) *SearchBuilder {
+	// Default to page 1
+	if page < 1 {
+		page = 1
+	}
+
+	// default limit
+	if limit <= 0 {
+		limit = 1000
+	}
+
 	searchBuilder := &SearchBuilder{
 		signedInUser: signedInUser,
 		limit:        limit,
+		page:         page,
 		permission:   permission,
 	}
 
@@ -88,12 +100,16 @@ func (sb *SearchBuilder) ToSql() (string, []interface{}) {
 		sb.buildMainQuery()
 	}
 
+	sb.sql.WriteString(`
+		ORDER BY dashboard.id ` + dialect.LimitOffset(sb.limit, (sb.page-1)*sb.limit) + `) as ids
+		INNER JOIN dashboard on ids.id = dashboard.id
+	`)
+
 	sb.sql.WriteString(`
 		LEFT OUTER JOIN dashboard folder on folder.id = dashboard.folder_id
 		LEFT OUTER JOIN dashboard_tag on dashboard.id = dashboard_tag.dashboard_id`)
 
-	sb.sql.WriteString(" ORDER BY dashboard.title ASC" + dialect.Limit(5000))
-
+	sb.sql.WriteString(" ORDER BY dashboard.title ASC")
 	return sb.sql.String(), sb.params
 }
 
@@ -133,12 +149,7 @@ func (sb *SearchBuilder) buildTagQuery() {
 	sb.buildSearchWhereClause()
 
 	// this ends the inner select (tag filtered part)
-	sb.sql.WriteString(`
-		GROUP BY dashboard.id HAVING COUNT(dashboard.id) >= ?
-		ORDER BY dashboard.id` + dialect.Limit(int64(sb.limit)) + `) as ids
-		INNER JOIN dashboard on ids.id = dashboard.id
-	`)
-
+	sb.sql.WriteString(`GROUP BY dashboard.id HAVING COUNT(dashboard.id) >= ? `)
 	sb.params = append(sb.params, len(sb.tags))
 }
 
@@ -152,7 +163,6 @@ func (sb *SearchBuilder) buildMainQuery() {
 	sb.sql.WriteString(` WHERE `)
 	sb.buildSearchWhereClause()
 
-	sb.sql.WriteString(` ORDER BY dashboard.title` + dialect.Limit(int64(sb.limit)) + `) as ids INNER JOIN dashboard on ids.id = dashboard.id `)
 }
 
 func (sb *SearchBuilder) buildSearchWhereClause() {