[v10.0.x] Alerting: Add limit query parameter to Loki-based ASH api, drop default limit from 5000 to 1000, extend visible time range for new ASH UI (#70857)

Alerting: Add limit query parameter to Loki-based ASH api, drop default limit from 5000 to 1000, extend visible time range for new ASH UI (#70769)

* Add limit query parameter

* Drop copy paste comment

* Extend history query limit to 30 days and 250 entries

* Fix history log entries ordering

* Update no history message, add empty history test

---------

Co-authored-by: Konrad Lalik <konrad.lalik@grafana.com>
(cherry picked from commit f94fb765b5)

Co-authored-by: Alexander Weaver <weaver.alex.d@gmail.com>

pkg/services/ngalert/api/api_ruler_history.go

@@ -27,6 +27,7 @@ const labelQueryPrefix = "labels_"
 func (srv *HistorySrv) RouteQueryStateHistory(c *contextmodel.ReqContext) response.Response {
 	from := c.QueryInt64("from")
 	to := c.QueryInt64("to")
+	limit := c.QueryInt("limit")
 	ruleUID := c.Query("ruleUID")
 
 	labels := make(map[string]string)
@@ -42,6 +43,7 @@ func (srv *HistorySrv) RouteQueryStateHistory(c *contextmodel.ReqContext) respon
 		SignedInUser: c.SignedInUser,
 		From:         time.Unix(from, 0),
 		To:           time.Unix(to, 0),
+		Limit:        limit,
 		Labels:       labels,
 	}
 	frame, err := srv.hist.Query(c.Req.Context(), query)

pkg/services/ngalert/models/history.go

@@ -13,5 +13,6 @@ type HistoryQuery struct {
 	Labels       map[string]string
 	From         time.Time
 	To           time.Time
+	Limit        int
 	SignedInUser *user.SignedInUser
 }

pkg/services/ngalert/state/historian/loki.go

@@ -43,7 +43,7 @@ const defaultQueryRange = 6 * time.Hour
 type remoteLokiClient interface {
 	ping(context.Context) error
 	push(context.Context, []stream) error
-	rangeQuery(ctx context.Context, logQL string, start, end int64) (queryRes, error)
+	rangeQuery(ctx context.Context, logQL string, start, end, limit int64) (queryRes, error)
 }
 
 // RemoteLokibackend is a state.Historian that records state history to an external Loki instance.
@@ -126,7 +126,7 @@ func (h *RemoteLokiBackend) Query(ctx context.Context, query models.HistoryQuery
 	}
 
 	// Timestamps are expected in RFC3339Nano.
-	res, err := h.client.rangeQuery(ctx, logQL, query.From.UnixNano(), query.To.UnixNano())
+	res, err := h.client.rangeQuery(ctx, logQL, query.From.UnixNano(), query.To.UnixNano(), int64(query.Limit))
 	if err != nil {
 		return nil, err
 	}

pkg/services/ngalert/state/historian/loki_http.go

@@ -17,7 +17,8 @@ import (
 	"github.com/weaveworks/common/http/client"
 )
 
-const defaultPageSize = 5000
+const defaultPageSize = 1000
+const maximumPageSize = 5000
 
 func NewRequester() client.Requester {
 	return &http.Client{}
@@ -225,11 +226,17 @@ func (c *httpLokiClient) setAuthAndTenantHeaders(req *http.Request) {
 	}
 }
 
-func (c *httpLokiClient) rangeQuery(ctx context.Context, logQL string, start, end int64) (queryRes, error) {
+func (c *httpLokiClient) rangeQuery(ctx context.Context, logQL string, start, end, limit int64) (queryRes, error) {
 	// Run the pre-flight checks for the query.
 	if start > end {
 		return queryRes{}, fmt.Errorf("start time cannot be after end time")
 	}
+	if limit < 1 {
+		limit = defaultPageSize
+	}
+	if limit > maximumPageSize {
+		limit = maximumPageSize
+	}
 
 	queryURL := c.cfg.ReadPathURL.JoinPath("/loki/api/v1/query_range")
 
@@ -237,7 +244,7 @@ func (c *httpLokiClient) rangeQuery(ctx context.Context, logQL string, start, en
 	values.Set("query", logQL)
 	values.Set("start", fmt.Sprintf("%d", start))
 	values.Set("end", fmt.Sprintf("%d", end))
-	values.Set("limit", fmt.Sprintf("%d", defaultPageSize))
+	values.Set("limit", fmt.Sprintf("%d", limit))
 
 	queryURL.RawQuery = values.Encode()
 

pkg/services/ngalert/state/historian/loki_http_test.go

@@ -131,13 +131,73 @@ func TestLokiHTTPClient(t *testing.T) {
 			now := time.Now().UTC().UnixNano()
 			q := `{from="state-history"}`
 
-			_, err := client.rangeQuery(context.Background(), q, now-100, now)
+			_, err := client.rangeQuery(context.Background(), q, now-100, now, 1100)
+
+			require.NoError(t, err)
+			params := req.lastRequest.URL.Query()
+			require.True(t, params.Has("limit"), "query params did not contain 'limit': %#v", params)
+			require.Equal(t, fmt.Sprint(1100), params.Get("limit"))
+		})
+
+		t.Run("uses default page size if limit not provided", func(t *testing.T) {
+			req := NewFakeRequester().WithResponse(&http.Response{
+				Status:        "200 OK",
+				StatusCode:    200,
+				Body:          io.NopCloser(bytes.NewBufferString(`{}`)),
+				ContentLength: int64(0),
+				Header:        make(http.Header, 0),
+			})
+			client := createTestLokiClient(req)
+			now := time.Now().UTC().UnixNano()
+			q := `{from="state-history"}`
+
+			_, err := client.rangeQuery(context.Background(), q, now-100, now, 0)
 
 			require.NoError(t, err)
 			params := req.lastRequest.URL.Query()
 			require.True(t, params.Has("limit"), "query params did not contain 'limit': %#v", params)
 			require.Equal(t, fmt.Sprint(defaultPageSize), params.Get("limit"))
 		})
+
+		t.Run("uses default page size if limit invalid", func(t *testing.T) {
+			req := NewFakeRequester().WithResponse(&http.Response{
+				Status:        "200 OK",
+				StatusCode:    200,
+				Body:          io.NopCloser(bytes.NewBufferString(`{}`)),
+				ContentLength: int64(0),
+				Header:        make(http.Header, 0),
+			})
+			client := createTestLokiClient(req)
+			now := time.Now().UTC().UnixNano()
+			q := `{from="state-history"}`
+
+			_, err := client.rangeQuery(context.Background(), q, now-100, now, -100)
+
+			require.NoError(t, err)
+			params := req.lastRequest.URL.Query()
+			require.True(t, params.Has("limit"), "query params did not contain 'limit': %#v", params)
+			require.Equal(t, fmt.Sprint(defaultPageSize), params.Get("limit"))
+		})
+
+		t.Run("uses maximum page size if limit too big", func(t *testing.T) {
+			req := NewFakeRequester().WithResponse(&http.Response{
+				Status:        "200 OK",
+				StatusCode:    200,
+				Body:          io.NopCloser(bytes.NewBufferString(`{}`)),
+				ContentLength: int64(0),
+				Header:        make(http.Header, 0),
+			})
+			client := createTestLokiClient(req)
+			now := time.Now().UTC().UnixNano()
+			q := `{from="state-history"}`
+
+			_, err := client.rangeQuery(context.Background(), q, now-100, now, maximumPageSize+1000)
+
+			require.NoError(t, err)
+			params := req.lastRequest.URL.Query()
+			require.True(t, params.Has("limit"), "query params did not contain 'limit': %#v", params)
+			require.Equal(t, fmt.Sprint(maximumPageSize), params.Get("limit"))
+		})
 	})
 }
 
@@ -194,7 +254,7 @@ func TestLokiHTTPClient_Manual(t *testing.T) {
 		end := time.Now().UnixNano()
 
 		// Authorized request should not fail against Grafana Cloud.
-		res, err := client.rangeQuery(context.Background(), logQL, start, end)
+		res, err := client.rangeQuery(context.Background(), logQL, start, end, defaultPageSize)
 		require.NoError(t, err)
 		require.NotNil(t, res)
 	})