WIP22: Improved helper func and testing

backend/pkg/api/instances.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"fmt"
 	"strconv"
+	"strings"
 	"time"
 
 	"github.com/doug-martin/goqu/v9"
@@ -48,6 +49,7 @@ const (
 
 const (
 	validityInterval postgresDuration = "1 days"
+	defaultInterval  time.Duration    = 2 * time.Hour
 )
 
 // Instance represents an instance running one or more applications for which
@@ -649,23 +651,38 @@ func (api *API) instanceStatsQuery(t *time.Time, duration *time.Duration) *goqu.
 	}
 
 	if duration == nil {
-		d := 2 * time.Hour
+		d := defaultInterval
 		duration = &d
 	}
 
 	// Helper function to convert duration to PostgreSQL interval string
 	durationToInterval := func(d time.Duration) string {
-		str := fmt.Sprintf("%d microseconds", d.Microseconds())
-		if d.Microseconds() > 999999 {
-			str = fmt.Sprintf("%d seconds", int(d.Seconds()))
+		parts := []string{}
+
+		hours := int(d.Hours())
+		if hours != 0 {
+			parts = append(parts, fmt.Sprintf("%d hours", hours))
+		}
+
+		remainder := d - time.Duration(hours)*time.Hour
+		minutes := int(remainder.Minutes())
+		if minutes != 0 {
+			parts = append(parts, fmt.Sprintf("%d minutes", minutes))
 		}
-		if d.Seconds() > 99 {
-			str = fmt.Sprintf("%d minutes", int(d.Minutes()))
+
+		remainder -= time.Duration(minutes) * time.Minute
+		seconds := int(remainder.Seconds())
+		if seconds != 0 {
+			parts = append(parts, fmt.Sprintf("%d seconds", seconds))
 		}
-		if d.Minutes() > 99 {
-			str = fmt.Sprintf("%d hours", int(d.Hours()))
+
+		remainder -= time.Duration(seconds) * time.Second
+		microseconds := remainder.Microseconds()
+		if microseconds != 0 {
+			parts = append(parts, fmt.Sprintf("%d microseconds", microseconds))
 		}
-		return str
+
+		return strings.Join(parts, " ")
 	}
 
 	interval := durationToInterval(*duration)

backend/pkg/api/instances_test.go

@@ -337,6 +337,8 @@ func TestUpdateInstanceStats(t *testing.T) {
 	assert.Equal(t, 2, len(instanceStats))
 	assert.Equal(t, "1.0.0", instanceStats[0].Version)
 	assert.Equal(t, 1, instanceStats[0].Instances)
+	assert.Equal(t, "1.0.1", instanceStats[1].Version)
+	assert.Equal(t, 2, instanceStats[1].Instances)
 
 	// Next test case: Switch tInstance1 and tInstance2 versions to workaround the 5-minutes-rate-limiting of the check-in time and add new instance
 	ts2 := time.Now().UTC()