add some test cases

pkg/backends/otlp/group.go

@@ -1,13 +1,24 @@
 package otlp
 
 import (
- "golang.org/x/exp/maps"
-
  "github.com/atlassian/gostatsd/pkg/backends/otlp/internal/data"
+ "golang.org/x/exp/maps"
 )
 
 type group map[uint64]data.ResourceMetrics
 
+func (g *group) Values() []data.ResourceMetrics {
+ return maps.Values(*g)
+}
+
+func (g *group) LenMetrics() int {
+ count := 0
+ for _, rm := range *g {
+ count += rm.CouneMetrics()
+ }
+ return count
+}
+
 // Group is used to ensure metrics that have the same resource attributes
 // are grouped together and it uses a fixed values to reduce potential memory
 // allocations compared to using a string value
@@ -24,10 +35,6 @@ func NewGroup(batchSize int) Group {
  }
 }
 
-func (g *group) Values() []data.ResourceMetrics {
- return maps.Values(*g)
-}
-
 func (g *Group) Insert(is data.InstrumentationScope, resources data.Map, m data.Metric) {
  key := resources.Hash()
 
@@ -44,7 +51,7 @@ func (g *Group) Insert(is data.InstrumentationScope, resources data.Map, m data.
  entry.AppendMetric(is, m)
  currentBatch[key] = entry
 
- if len(currentBatch) == g.batchSize {
+ if currentBatch.LenMetrics() == g.batchSize {
  g.batches = append(g.batches, make(group))
  }
 }

pkg/backends/otlp/group_test.go

@@ -58,47 +58,75 @@ func TestGroupInsert(t *testing.T) {
 func TestGroupBatch(t *testing.T) {
  t.Parallel()
 
- g := NewGroup(2)
+ for _, tc := range []struct {
+ name string
+ batchSize int
+ metricsAdded map[string][]string // map[resourceMetrics][]metricNames
+ wantNumOfBatches int
+ }{
+ {
+ name: "no metrics",
+ batchSize: 2,
+ metricsAdded: map[string][]string{},
+ wantNumOfBatches: 1, // Must have at least one batch
+ },
+ {
+ name: "metrics in one resource metrics exceeds batch limit should be split into two groups",
+ batchSize: 2,
+ metricsAdded: map[string][]string{
+ "r1": {"m1", "m2", "m3", "m4", "m5"},
+ },
+ wantNumOfBatches: 3,
+ },
+ {
+ name: "metrics in multiple resource metrics doesn't exceeds batch limit stay in one group",
+ batchSize: 10,
+ metricsAdded: map[string][]string{
+ "r1": {"m1", "m2", "m3"},
+ "r2": {"m1", "m2", "m3"},
+ "r3": {"m1", "m2", "m3"},
+ },
+ wantNumOfBatches: 1,
+ },
+ {
+ name: "should properly split metrics into groups according to batch size",
+ batchSize: 5,
+ metricsAdded: map[string][]string{
+ "r1": {"m1", "m2", "m3", "m4", "m5", "m6", "m7", "m8", "m9", "m10"},
+ "r2": {"m1"},
+ "r3": {"m1", "m2", "m3", "m4", "m5"},
+ "r4": {"m1", "m2", "m3"},
+ },
+ wantNumOfBatches: 4,
+ },
+ } {
+ tc := tc
+ t.Run(tc.name, func(t *testing.T) {
+ t.Parallel()
+ g := NewGroup(tc.batchSize)
+ is := data.NewInstrumentationScope("gostatsd/aggregation", "v1.0.0")
+ for rm, metricNames := range tc.metricsAdded {
+ for _, metricName := range metricNames {
+ insertMetric(&g, is, rm, metricName)
+ }
+ }
 
- is := data.NewInstrumentationScope("gostatsd/aggregation", "v1.0.0")
+ assert.Len(t, g.batches, tc.wantNumOfBatches, "Must have %d groups", tc.wantNumOfBatches)
+ })
+ }
+}
 
+func insertMetric(g *Group, is data.InstrumentationScope, serviceName string, metricName string) {
  g.Insert(
  is,
  data.NewMap(
  data.WithStatsdDelimitedTags(
  []string{
- "service.name:my-awesome-service",
+ "service.name:" + serviceName,
  "service.region:local",
  },
  ),
  ),
- data.NewMetric("my-metric"),
+ data.NewMetric(metricName),
  )
- g.Insert(
- is,
- data.NewMap(
- data.WithStatsdDelimitedTags(
- []string{
- "service.name:my-awesome-service",
- "service.region:local",
- },
- ),
- ),
- data.NewMetric("my-metric"),
- )
- g.Insert(
- is,
- data.NewMap(
- data.WithStatsdDelimitedTags(
- []string{
- "service.name:my-other-service",
- "service.region:local",
- },
- ),
- ),
- data.NewMetric("my-metric"),
- )
-
- batches := g.batches
- assert.Equal(t, 2, len(batches))
 }