Revert "Revert "pkg/trace: make changes to allow merging the reposito…

…ry""

This reverts commit 7835571.

LICENSE-3rdparty.csv

@@ -152,3 +152,6 @@ core,k8s.io/apiextensions-apiserver,Apache-2.0
 core,github.com/docker/spdystream,Apache-2.0
 core,gopkg.in/square/go-jose.v2,Apache-2.0
 core,github.com/opencontainers/go-digest,Apache-2.0
+core,github.com/philhofer/fwd,MIT
+core,github.com/DataDog/datadog-go,MIT
+core,github.com/tinylib/msgp,MIT

cmd/trace-agent/agent_test.go

@@ -443,7 +443,7 @@ func TestEventProcessorFromConfLegacy(t *testing.T) {
 		{name: "metrics/overrides/legacy", intakeSPS: 100, serviceName: "serviceC", opName: "opC", extractionRate: 1, priority: sampler.PriorityNone, expectedEPS: 100, deltaPct: 0.1, duration: 10 * time.Second},
 	} {
 		testEventProcessorFromConf(t, &config.AgentConfig{
-			MaxEPS:                      testMaxEPS,
+			MaxEPS: testMaxEPS,
 			AnalyzedRateByServiceLegacy: rateByService,
 		}, testCase)
 	}

cmd/trace-agent/main_windows.go

@@ -23,6 +23,7 @@ import (
 
 var elog debug.Log
 
+// ServiceName specifies the service name used in the operating system.
 const ServiceName = "datadog-trace-agent"
 
 type myservice struct{}
@@ -265,7 +266,7 @@ func exePath() (string, error) {
 			if !fi.Mode().IsDir() {
 				return p, nil
 			}
-			err = fmt.Errorf("%s is directory", p)
+			return "", fmt.Errorf("%s is directory", p)
 		}
 	}
 	return "", err

cmd/trace-agent/sampler.go

@@ -15,7 +15,7 @@ import (
 	"github.com/DataDog/datadog-agent/pkg/trace/watchdog"
 )
 
-// Sampler chooses wich spans to write to the API
+// Sampler chooses which spans to write to the API
 type Sampler struct {
 	// For stats
 	keptTraceCount  uint64

cmd/trace-agent/service_mapper.go

@@ -74,7 +74,7 @@ func (s *ServiceMapper) update(metadata pb.ServicesMetadata) {
 			continue
 		}
 
-		// We do this inside the for loop to avoid unecessary memory allocations.
+		// We do this inside the for loop to avoid unnecessary memory allocations.
 		// After few method executions, the cache will be warmed up and this section be skipped altogether.
 		if changes == nil {
 			changes = make(pb.ServicesMetadata)

cmd/trace-agent/sublayers_test.go

@@ -20,8 +20,8 @@ func TestExtractTopLevelSubtracesWithSimpleTrace(t *testing.T) {
 	}
 
 	expected := []Subtrace{
-		Subtrace{trace[0], trace},
-		Subtrace{trace[1], []*pb.Span{trace[1], trace[2], trace[3]}},
+		{trace[0], trace},
+		{trace[1], []*pb.Span{trace[1], trace[2], trace[3]}},
 	}
 
 	traceutil.ComputeTopLevel(trace)
@@ -50,8 +50,8 @@ func TestExtractTopLevelSubtracesShouldIgnoreLeafTopLevel(t *testing.T) {
 	}
 
 	expected := []Subtrace{
-		Subtrace{trace[0], trace},
-		Subtrace{trace[1], []*pb.Span{trace[1], trace[2]}},
+		{trace[0], trace},
+		{trace[1], []*pb.Span{trace[1], trace[2]}},
 	}
 
 	traceutil.ComputeTopLevel(trace)
@@ -79,8 +79,8 @@ func TestExtractTopLevelSubtracesWorksInSpiteOfCycles(t *testing.T) {
 	}
 
 	expected := []Subtrace{
-		Subtrace{trace[0], trace},
-		Subtrace{trace[1], []*pb.Span{trace[1], trace[2]}},
+		{trace[0], trace},
+		{trace[1], []*pb.Span{trace[1], trace[2]}},
 	}
 
 	traceutil.ComputeTopLevel(trace)

pkg/trace/agent/normalizer_test.go

@@ -90,9 +90,9 @@ func TestNormalizeName(t *testing.T) {
 
 func TestNormalizeNameFailure(t *testing.T) {
 	invalidNames := []string{
-		"",                                // Empty.
-		"/",                               // No alphanumerics.
-		"//",                              // Still no alphanumerics.
+		"",   // Empty.
+		"/",  // No alphanumerics.
+		"//", // Still no alphanumerics.
 		strings.Repeat("x", MaxNameLen+1), // Too long.
 	}
 	s := testSpan()
@@ -387,7 +387,7 @@ func TestNormalizeInvalidUTF8(t *testing.T) {
 func BenchmarkNormalization(b *testing.B) {
 	b.ReportAllocs()
 
-	for i := 0; i < b.N; i += 1 {
+	for i := 0; i < b.N; i++ {
 		Normalize(testSpan())
 	}
 }

pkg/trace/agent/processed_trace.go

@@ -5,6 +5,7 @@ import (
 	"github.com/DataDog/datadog-agent/pkg/trace/sampler"
 )
 
+// ProcessedTrace represents a trace being processed in the agent.
 type ProcessedTrace struct {
 	Trace         pb.Trace
 	WeightedTrace WeightedTrace
@@ -14,13 +15,15 @@ type ProcessedTrace struct {
 	Sampled       bool
 }
 
+// Weight returns the weight at the root span.
 func (pt *ProcessedTrace) Weight() float64 {
 	if pt.Root == nil {
 		return 1.0
 	}
 	return sampler.Weight(pt.Root)
 }
 
+// GetSamplingPriority returns the sampling priority of the root span.
 func (pt *ProcessedTrace) GetSamplingPriority() (sampler.SamplingPriority, bool) {
 	return sampler.GetSamplingPriority(pt.Root)
 }