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

docs/sources/http_api/folder_dashboard_search.md

@@ -23,7 +23,8 @@ Query parameters:
 - **dashboardIds** – List of dashboard id's to search for
 - **folderIds** – List of folder id's to search in for dashboards
 - **starred** – Flag indicating if only starred Dashboards should be returned
-- **limit** – Limit the number of returned results
+- **limit** – Limit the number of returned results (max 5000)
+- **page** – Use this parameter to access hits beyond limit. Numbering starts at 1. limit param acts as page size.
 
 **Example request for retrieving folders and dashboards of the general folder**:
 
@@ -95,4 +96,4 @@ Content-Type: application/json
     "uri":"db/production-overview" // deprecated in Grafana v5.0
   }
 ]
-```
+```

pkg/api/api.go

@@ -325,7 +325,7 @@ func (hs *HTTPServer) registerRoutes() {
 		})
 
 		// Search
-		apiRoute.Get("/search/", Search)
+		apiRoute.Get("/search/", Wrap(Search))
 
 		// metrics
 		apiRoute.Post("/tsdb/query", bind(dtos.MetricRequest{}), Wrap(hs.QueryMetrics))

pkg/api/folder.go

@@ -12,7 +12,7 @@ import (
 
 func GetFolders(c *m.ReqContext) Response {
 	s := dashboards.NewFolderService(c.OrgId, c.SignedInUser)
-	folders, err := s.GetFolders(c.QueryInt("limit"))
+	folders, err := s.GetFolders(c.QueryInt64("limit"))
 
 	if err != nil {
 		return toFolderError(err)

pkg/api/folder_test.go

@@ -213,7 +213,7 @@ type fakeFolderService struct {
 	DeletedFolderUids    []string
 }
 
-func (s *fakeFolderService) GetFolders(limit int) ([]*m.Folder, error) {
+func (s *fakeFolderService) GetFolders(limit int64) ([]*m.Folder, error) {
 	return s.GetFoldersResult, s.GetFoldersError
 }
 

pkg/api/search.go

@@ -9,16 +9,17 @@ import (
 	"github.com/grafana/grafana/pkg/services/search"
 )
 
-func Search(c *m.ReqContext) {
+func Search(c *m.ReqContext) Response {
 	query := c.Query("query")
 	tags := c.QueryStrings("tag")
 	starred := c.Query("starred")
-	limit := c.QueryInt("limit")
+	limit := c.QueryInt64("limit")
+	page := c.QueryInt64("page")
 	dashboardType := c.Query("type")
 	permission := m.PERMISSION_VIEW
 
-	if limit == 0 {
-		limit = 1000
+	if limit > 5000 {
+		return Error(422, "Limit is above maximum allowed (5000), use page parameter to access hits beyond limit", nil)
 	}
 
 	if c.Query("permission") == "Edit" {
@@ -46,6 +47,7 @@ func Search(c *m.ReqContext) {
 		Tags:         tags,
 		SignedInUser: c.SignedInUser,
 		Limit:        limit,
+		Page:         page,
 		IsStarred:    starred == "true",
 		OrgId:        c.OrgId,
 		DashboardIds: dbIDs,
@@ -56,10 +58,9 @@ func Search(c *m.ReqContext) {
 
 	err := bus.Dispatch(&searchQuery)
 	if err != nil {
-		c.JsonApiErr(500, "Search failed", err)
-		return
+		return Error(500, "Search failed", err)
 	}
 
 	c.TimeRequest(metrics.M_Api_Dashboard_Search)
-	c.JSON(200, searchQuery.Result)
+	return JSON(200, searchQuery.Result)
 }

pkg/services/dashboards/folder_service.go

@@ -9,7 +9,7 @@ import (
 
 // FolderService service for operating on folders
 type FolderService interface {
-	GetFolders(limit int) ([]*models.Folder, error)
+	GetFolders(limit int64) ([]*models.Folder, error)
 	GetFolderByID(id int64) (*models.Folder, error)
 	GetFolderByUID(uid string) (*models.Folder, error)
 	CreateFolder(cmd *models.CreateFolderCommand) error
@@ -25,11 +25,7 @@ var NewFolderService = func(orgId int64, user *models.SignedInUser) FolderServic
 	}
 }
 
-func (dr *dashboardServiceImpl) GetFolders(limit int) ([]*models.Folder, error) {
-	if limit == 0 {
-		limit = 1000
-	}
-
+func (dr *dashboardServiceImpl) GetFolders(limit int64) ([]*models.Folder, error) {
 	searchQuery := search.Query{
 		SignedInUser: dr.user,
 		DashboardIds: make([]int64, 0),

pkg/services/search/handlers.go

@@ -31,6 +31,7 @@ func (s *SearchService) searchHandler(query *Query) error {
 		FolderIds:    query.FolderIds,
 		Tags:         query.Tags,
 		Limit:        query.Limit,
+		Page:         query.Page,
 		Permission:   query.Permission,
 	}
 
@@ -44,10 +45,6 @@ func (s *SearchService) searchHandler(query *Query) error {
 	// sort main result array
 	sort.Sort(hits)
 
-	if len(hits) > query.Limit {
-		hits = hits[0:query.Limit]
-	}
-
 	// sort tags
 	for _, hit := range hits {
 		sort.Strings(hit.Tags)

pkg/services/search/models.go

@@ -48,7 +48,8 @@ type Query struct {
 	Tags         []string
 	OrgId        int64
 	SignedInUser *models.SignedInUser
-	Limit        int
+	Limit        int64
+	Page         int64
 	IsStarred    bool
 	Type         string
 	DashboardIds []int64
@@ -67,7 +68,8 @@ type FindPersistedDashboardsQuery struct {
 	Type         string
 	FolderIds    []int64
 	Tags         []string
-	Limit        int
+	Limit        int64
+	Page         int64
 	Permission   models.PermissionType
 
 	Result HitList

pkg/services/sqlstore/dashboard.go

@@ -197,12 +197,7 @@ type DashboardSearchProjection struct {
 }
 
 func findDashboards(query *search.FindPersistedDashboardsQuery) ([]DashboardSearchProjection, error) {
-	limit := query.Limit
-	if limit == 0 {
-		limit = 1000
-	}
-
-	sb := NewSearchBuilder(query.SignedInUser, limit, query.Permission).
+	sb := NewSearchBuilder(query.SignedInUser, query.Limit, query.Page, query.Permission).
 		WithTags(query.Tags).
 		WithDashboardIdsIn(query.DashboardIds)
 

pkg/services/sqlstore/dashboard_test.go

@@ -259,6 +259,35 @@ func TestDashboardDataAccess(t *testing.T) {
 				So(hit.FolderTitle, ShouldEqual, "")
 			})
 
+			Convey("Should be able to limit search", func() {
+				query := search.FindPersistedDashboardsQuery{
+					OrgId:        1,
+					Limit:        1,
+					SignedInUser: &m.SignedInUser{OrgId: 1, OrgRole: m.ROLE_EDITOR},
+				}
+
+				err := SearchDashboards(&query)
+				So(err, ShouldBeNil)
+
+				So(len(query.Result), ShouldEqual, 1)
+				So(query.Result[0].Title, ShouldEqual, "1 test dash folder")
+			})
+
+			Convey("Should be able to search beyond limit using paging", func() {
+				query := search.FindPersistedDashboardsQuery{
+					OrgId:        1,
+					Limit:        1,
+					Page:         2,
+					SignedInUser: &m.SignedInUser{OrgId: 1, OrgRole: m.ROLE_EDITOR},
+				}
+
+				err := SearchDashboards(&query)
+				So(err, ShouldBeNil)
+
+				So(len(query.Result), ShouldEqual, 1)
+				So(query.Result[0].Title, ShouldEqual, "test dash 23")
+			})
+
 			Convey("Should be able to search for a dashboard folder's children", func() {
 				query := search.FindPersistedDashboardsQuery{
 					OrgId:        1,

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() {

pkg/services/sqlstore/search_builder_test.go

@@ -14,7 +14,7 @@ func TestSearchBuilder(t *testing.T) {
 			UserId: 1,
 		}
 
-		sb := NewSearchBuilder(signedInUser, 1000, m.PERMISSION_VIEW)
+		sb := NewSearchBuilder(signedInUser, 1000, 0, m.PERMISSION_VIEW)
 
 		Convey("When building a normal search", func() {
 			sql, params := sb.IsStarred().WithTitle("test").ToSql()