Add unit tests for the query and query_range endpoints

Author: Blagoj Atanasovski

pkg/api/health_test.go

@@ -24,7 +24,8 @@ func (m *mockHealthChecker) HealthCheck() error {
 }
 
 func TestHealth(t *testing.T) {
-	log.Init("debug")
+	_ = log.Init("debug")
+
 	testCases := []struct {
 		name                   string
 		httpStatus             int

pkg/api/ranged_query.go renamed to pkg/api/query_range.go

@@ -0,0 +1,203 @@
+package api
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"fmt"
+	"github.com/prometheus/client_golang/prometheus"
+	"github.com/prometheus/prometheus/promql"
+	"github.com/timescale/timescale-prometheus/pkg/log"
+	tspromql "github.com/timescale/timescale-prometheus/pkg/promql"
+	"math"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestRangedQuery(t *testing.T) {
+	_ = log.Init("debug")
+	testCases := []struct {
+		name        string
+		timeout     string
+		querier     *mockQuerier
+		metric      string
+		start       string
+		end         string
+		step        string
+		expectCode  int
+		expectError string
+		canceled    bool
+	}{
+		{
+			name:        "Start is unparsable",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "unparsable",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "End is unparsable",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1.1",
+			end:         "unparsable",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "End is before start",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1.1",
+			end:         "1",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "Step is unparasable",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1",
+			end:         "2",
+			step:        "unparsable",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "Step is non-positive",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1",
+			end:         "2",
+			step:        "0s",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "Resolution is too high",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1",
+			end:         "11002",
+			step:        "1s",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "Timeout is unparsable",
+			expectCode:  http.StatusBadRequest,
+			metric:      "m",
+			start:       "1",
+			end:         "2.2",
+			timeout:     "unparsable",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "No query given",
+			expectCode:  http.StatusBadRequest,
+			metric:      "",
+			start:       "1",
+			end:         "2",
+			step:        "1s",
+			timeout:     "1m",
+			expectError: "bad_data",
+			querier:     &mockQuerier{},
+		}, {
+			name:        "Timeout query",
+			start:       "1",
+			end:         "2",
+			step:        "1s",
+			expectCode:  http.StatusServiceUnavailable,
+			expectError: "timeout",
+			timeout:     "1s",
+			metric:      "m",
+			querier: &mockQuerier{
+				timeToSleep: 2 * time.Second,
+			},
+		}, {
+			name:        "Cancel query",
+			start:       "1",
+			end:         "2",
+			step:        "1s",
+			expectCode:  http.StatusServiceUnavailable,
+			expectError: "canceled",
+			metric:      "m",
+			querier:     &mockQuerier{},
+			canceled:    true,
+		}, {
+			name:        "Select error",
+			start:       "1",
+			end:         "2",
+			step:        "1s",
+			expectCode:  http.StatusUnprocessableEntity,
+			expectError: "execution",
+			metric:      "m",
+			querier:     &mockQuerier{err: fmt.Errorf("some error")},
+			timeout:     "30s",
+		}, {
+			name:       "All good",
+			start:      "1",
+			end:        "2",
+			step:       "1s",
+			expectCode: http.StatusOK,
+			metric:     "m",
+			querier:    &mockQuerier{},
+			timeout:    "30s",
+		},
+	}
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			timeout, _ := parseDuration(tc.timeout)
+			engine := promql.NewEngine(
+				promql.EngineOpts{
+					Logger:     log.GetLogger(),
+					Reg:        prometheus.NewRegistry(),
+					MaxSamples: math.MaxInt32,
+					Timeout:    timeout,
+				},
+			)
+			handler := QueryRange(engine, tspromql.NewQueryable(tc.querier))
+			queryUrl := constructRangedQuery(tc.metric, tc.start, tc.end, tc.step, tc.timeout)
+			w := doRangedQuery(t, handler, queryUrl, tc.canceled)
+
+			if w.Code != tc.expectCode {
+				t.Errorf("Unexpected HTTP status code received: got %d wanted %d", w.Code, tc.expectCode)
+				return
+			}
+			if tc.expectError != "" {
+				var er errResponse
+				_ = json.NewDecoder(bytes.NewReader(w.Body.Bytes())).Decode(&er)
+				if tc.expectError != er.ErrorType {
+					t.Errorf("expected error of type %s, got %s", tc.expectError, er.ErrorType)
+					return
+				}
+			}
+		})
+
+	}
+
+}
+
+func constructRangedQuery(metric, start, end, step, timeout string) string {
+	return fmt.Sprintf(
+		"http://localhost:9090/query_range?query=%s&start=%s&end=%s&step=%s&timeout=%s",
+		metric, start, end, step, timeout,
+	)
+}
+
+func doRangedQuery(t *testing.T, queryHandler http.Handler, url string, canceled bool) *httptest.ResponseRecorder {
+	ctx, cancelFunc := context.WithCancel(context.Background())
+	req, err := http.NewRequestWithContext(ctx, "GET", url, nil)
+	if err != nil {
+		t.Errorf("%v", err)
+	}
+	req.Header.Set(
+		"Content-Type",
+		"application/x-www-form-urlencoded; param=value",
+	)
+	w := httptest.NewRecorder()
+	if canceled {
+		cancelFunc()
+	} else {
+		defer cancelFunc()
+	}
+	queryHandler.ServeHTTP(w, req)
+	return w
+}