Fix ListEvaluationHistory RPC faulty navigation to next page.

The SQL statement underlying ListEvaluationHistory RPC has fixed
sorting. This does not create problems when navigating in the same
direction, but creates problem when changing direction from pages
further away from the first.

This change solves the issue by determining the sort direction
dynamically and inverting the records at the service layer
accordingly.

Fixes #3966

database/query/eval_history.sql

@@ -162,5 +162,7 @@ SELECT s.id::uuid AS evaluation_id,
         OR s.evaluation_time BETWEEN sqlc.narg(fromts) AND sqlc.narg(tots))
    -- implicit filter by project id
    AND j.id = sqlc.arg(projectId)
- ORDER BY s.evaluation_time DESC
+ ORDER BY
+ CASE WHEN sqlc.narg(next)::timestamp without time zone IS NULL THEN s.evaluation_time END ASC,
+ CASE WHEN sqlc.narg(prev)::timestamp without time zone IS NULL THEN s.evaluation_time END DESC
  LIMIT sqlc.arg(size)::integer;

internal/history/service.go

@@ -20,6 +20,7 @@ import (
 	"database/sql"
 	"errors"
 	"fmt"
+	"slices"
 
 	"github.com/google/uuid"
 
@@ -203,6 +204,10 @@ func (_ *evaluationHistoryService) ListEvaluationHistory(
 		return nil, errors.New("internal error")
 	}
 
+	if cursor != nil && cursor.Direction == Next {
+		slices.Reverse(rows)
+	}
+
 	result := &ListEvaluationHistoryResult{
 		Data: rows,
 	}

internal/history/service_test.go

@@ -208,6 +208,90 @@ func TestListEvaluationHistory(t *testing.T) {
 			},
 		},
 
+		// cursor flips on direction
+		{
+			name: "prev does not flip",
+			dbSetup: dbf.NewDBMock(
+				withListEvaluationHistory(nil, nil,
+					makeHistoryRow(
+						uuid1,
+						evaluatedAt1,
+						entityType,
+						remediation,
+						alert,
+					),
+					makeHistoryRow(
+						uuid2,
+						evaluatedAt2,
+						entityType,
+						remediation,
+						alert,
+					),
+				),
+			),
+			cursor: &ListEvaluationCursor{
+				Direction: Prev,
+			},
+			checkf: func(t *testing.T, rows *ListEvaluationHistoryResult) {
+				t.Helper()
+
+				require.NotNil(t, rows)
+				require.Len(t, rows.Data, 2)
+
+				// database order is maintained
+				item1 := rows.Data[0]
+				require.Equal(t, uuid1, item1.EvaluationID)
+				require.Equal(t, evaluatedAt1, item1.EvaluatedAt)
+				require.Equal(t, uuid1, item1.EntityID)
+
+				item2 := rows.Data[1]
+				require.Equal(t, uuid2, item2.EvaluationID)
+				require.Equal(t, evaluatedAt2, item2.EvaluatedAt)
+				require.Equal(t, uuid2, item2.EntityID)
+			},
+		},
+		{
+			name: "next does flip",
+			dbSetup: dbf.NewDBMock(
+				withListEvaluationHistory(nil, nil,
+					makeHistoryRow(
+						uuid2,
+						evaluatedAt2,
+						entityType,
+						remediation,
+						alert,
+					),
+					makeHistoryRow(
+						uuid1,
+						evaluatedAt1,
+						entityType,
+						remediation,
+						alert,
+					),
+				),
+			),
+			cursor: &ListEvaluationCursor{
+				Direction: Next,
+			},
+			checkf: func(t *testing.T, rows *ListEvaluationHistoryResult) {
+				t.Helper()
+
+				require.NotNil(t, rows)
+				require.Len(t, rows.Data, 2)
+
+				// database order is maintained
+				item1 := rows.Data[0]
+				require.Equal(t, uuid1, item1.EvaluationID)
+				require.Equal(t, evaluatedAt1, item1.EvaluatedAt)
+				require.Equal(t, uuid1, item1.EntityID)
+
+				item2 := rows.Data[1]
+				require.Equal(t, uuid2, item2.EvaluationID)
+				require.Equal(t, evaluatedAt2, item2.EvaluatedAt)
+				require.Equal(t, uuid2, item2.EntityID)
+			},
+		},
+
 		// cursor
 		{
 			name: "cursor next",
@@ -661,6 +745,7 @@ func TestListEvaluationHistory(t *testing.T) {
 	}
 }
 
+//nolint:unparam
 func makeHistoryRow(
 	id uuid.UUID,
 	evaluatedAt time.Time,