fix: support creating span processor with max batch size (#71)

* fix: create span processor with batch size

* chore: make batch size configurable using a command-line flag

* chore: use testing library to set up env vars in tests

* chore: extract creation of test containers to a method

* fix: swap json objects parsing

* fix: swap back

* chore: increase batch size in tests

README.md

@@ -141,6 +141,7 @@ This tool is able to override the following attributes:
 
 | Attribute | Flag | Default value | Description |
 | --------- | ---- | ------------- | ----------- |
+| Max Batch Size | --batch-size | `10` | Maximum export batch size allowed when creating a BatchSpanProcessor. |
 | Repository Path | --repository-path | `.` | Path to the SCM repository to be read. |
 | Service Name | --service-name | `junit2otlp` | Overrides OpenTelemetry's service name. If the `OTEL_SERVICE_NAME` environment variable is set, it will take precedence over any other value. |
 | Service Version | --service-version | Empty | Overrides OpenTelemetry's service version. If the `OTEL_SERVICE_VERSION` environment variable is set, it will take precedence over any other value. |

main.go

@@ -23,6 +23,9 @@ import (
 	"go.opentelemetry.io/otel/trace"
 )
 
+const defaultMaxBatchSize = 10
+
+var batchSizeFlag int
 var repositoryPathFlag string
 var serviceNameFlag string
 var serviceVersionFlag string
@@ -31,6 +34,7 @@ var traceNameFlag string
 var runtimeAttributes []attribute.KeyValue
 
 func init() {
+	flag.IntVar(&batchSizeFlag, "batch-size", defaultMaxBatchSize, "Maximum export batch size allowed when creating a BatchSpanProcessor")
 	flag.StringVar(&repositoryPathFlag, "repository-path", getDefaultwd(), "Path to the SCM repository to be read")
 	flag.StringVar(&serviceNameFlag, "service-name", "", "OpenTelemetry Service Name to be used when sending traces and metrics for the jUnit report")
 	flag.StringVar(&serviceVersionFlag, "service-version", "", "OpenTelemetry Service Version to be used when sending traces and metrics for the jUnit report")
@@ -182,7 +186,12 @@ func initTracerProvider(ctx context.Context, res *resource.Resource) (*sdktrace.
 
 	tracerProvider := sdktrace.NewTracerProvider(
 		sdktrace.WithResource(res),
-		sdktrace.WithSpanProcessor(sdktrace.NewBatchSpanProcessor(traceExporter)),
+		sdktrace.WithSpanProcessor(
+			sdktrace.NewBatchSpanProcessor(
+				traceExporter,
+				sdktrace.WithMaxExportBatchSize(batchSizeFlag),
+			),
+		),
 	)
 
 	otel.SetTracerProvider(tracerProvider)

main_test.go

@@ -125,9 +125,7 @@ func requireAttributeInArray(t *testing.T, attributes []TestAttribute, key strin
 	return TestAttribute{}
 }
 
-func Test_Main_SampleXML(t *testing.T) {
-	t.Setenv("BRANCH", "main")
-
+func setupRuntimeDependencies(t *testing.T) (context.Context, string, testcontainers.Container) {
 	ctx := context.Background()
 
 	// create file for otel to store the traces
@@ -197,12 +195,22 @@ func Test_Main_SampleXML(t *testing.T) {
 	t.Setenv("OTEL_EXPORTER_OTLP_HEADERS", "")
 	t.Setenv("OTEL_SERVICE_NAME", "jaeger-srv-test")
 
+	return ctx, reportFilePath, otelCollector
+}
+
+func Test_Main_SampleXML(t *testing.T) {
+	t.Setenv("BRANCH", "main")
+	batchSizeFlag = 25
+
+	ctx, reportFilePath, otelCollector := setupRuntimeDependencies(t)
+
 	defer func() {
+		batchSizeFlag = defaultMaxBatchSize
 		// clean up test report
 		os.Remove(reportFilePath)
 	}()
 
-	err = Main(context.Background(), &TestReader{testFile: "TEST-sample.xml"})
+	err := Main(context.Background(), &TestReader{testFile: "TEST-sample.xml"})
 	require.NoError(t, err)
 
 	// wait for the file to be written by the otel-exporter