Add support for AWS Lambda entry spans triggered by API GW and ALB

instana · Nov 13, 2020 · ae3920f · ae3920f
1 parent 9d7c30c
commit ae3920f
Show file tree

Hide file tree

Showing 2 changed files with 105 additions and 17 deletions.
diff --git a/json_span.go b/json_span.go
@@ -558,31 +558,53 @@ func NewGCPPubSubSpanTags(span *spanS) GCPPubSubSpanTags {
 	return tags
 }
 
-// AWSLambdaSpanData is the base span data type for AWS Lambda entry spans
-type AWSLambdaSpanData struct {
-	Snapshot struct {
-		ARN     string `json:"arn"`
-		Runtime string `json:"runtime"`
-		Name    string `json:"functionName,omitempty"`
-		Version string `json:"functionVersion,omitempty"`
-	} `json:"lambda"`
-}
-
-// NewAWSLambdaSpanData initializes a new AWSLambdaSpanData from span
-func NewAWSLambdaSpanData(span *spanS) AWSLambdaSpanData {
-	var d AWSLambdaSpanData
-	d.Snapshot.Runtime = "go"
+// AWSLambdaSpanTags contains fields within the `data.lambda` section of an OT span document
+type AWSLambdaSpanTags struct {
+	// ARN is the ARN of invoked AWS Lambda function with the version attached
+	ARN string `json:"arn"`
+	// Runtime is an Instana constant for this AWS lambda runtime (always "go")
+	Runtime string `json:"runtime"`
+	// Name is the name of invoked function
+	Name string `json:"functionName,omitempty"`
+	// Version is either the numeric version or $LATEST
+	Version string `json:"functionVersion,omitempty"`
+}
+
+// NewAWSLambdaSpanTags extracts AWS Lambda entry span tags from a tracer span
+func NewAWSLambdaSpanTags(span *spanS) AWSLambdaSpanTags {
+	tags := AWSLambdaSpanTags{Runtime: "go"}
 
 	if v, ok := span.Tags["lambda.arn"]; ok {
-		readStringTag(&d.Snapshot.ARN, v)
+		readStringTag(&tags.ARN, v)
 	}
 
 	if v, ok := span.Tags["lambda.name"]; ok {
-		readStringTag(&d.Snapshot.Name, v)
+		readStringTag(&tags.Name, v)
 	}
 
 	if v, ok := span.Tags["lambda.version"]; ok {
-		readStringTag(&d.Snapshot.Version, v)
+		readStringTag(&tags.Version, v)
+	}
+
+	return tags
+}
+
+// AWSLambdaSpanData is the base span data type for AWS Lambda entry spans
+type AWSLambdaSpanData struct {
+	Snapshot AWSLambdaSpanTags `json:"lambda"`
+	HTTP     *HTTPSpanTags     `json:"http,omitempty"`
+}
+
+// NewAWSLambdaSpanData initializes a new AWSLambdaSpanData from span
+func NewAWSLambdaSpanData(span *spanS) AWSLambdaSpanData {
+	d := AWSLambdaSpanData{
+		Snapshot: NewAWSLambdaSpanTags(span),
+	}
+
+	switch span.Tags["lambda.trigger"] {
+	case "aws:api.gateway", "aws:application.load.balancer":
+		tags := NewHTTPSpanTags(span)
+		d.HTTP = &tags
 	}
 
 	return d

diff --git a/json_span_test.go b/json_span_test.go
@@ -5,6 +5,7 @@ import (
 
 	instana "github.com/instana/go-sensor"
 	"github.com/instana/testify/assert"
+	"github.com/opentracing/opentracing-go"
 )
 
 func TestRegisteredSpanType_ExtractData(t *testing.T) {
@@ -84,3 +85,68 @@ func TestSpanKind_String(t *testing.T) {
 		})
 	}
 }
+
+func TestNewAWSLambdaSpanData(t *testing.T) {
+	examples := map[string]struct {
+		Tags     opentracing.Tags
+		Expected instana.AWSLambdaSpanData
+	}{
+		"aws:api.gateway": {
+			Tags: opentracing.Tags{
+				"http.protocol": "https",
+				"http.url":      "https://example.com/lambda",
+				"http.host":     "example.com",
+				"http.method":   "GET",
+				"http.path":     "/lambda",
+				"http.params":   "q=test&secret=classified",
+				"http.header":   map[string]string{"x-custom-header-1": "test"},
+				"http.status":   404,
+				"http.error":    "Not Found",
+			},
+			Expected: instana.AWSLambdaSpanData{
+				Snapshot: instana.AWSLambdaSpanTags{
+					ARN:     "lambda-arn-1",
+					Runtime: "go",
+					Name:    "test-lambda",
+					Version: "42",
+				},
+				HTTP: &instana.HTTPSpanTags{
+					URL:      "https://example.com/lambda",
+					Status:   404,
+					Method:   "GET",
+					Path:     "/lambda",
+					Params:   "q=test&secret=classified",
+					Headers:  map[string]string{"x-custom-header-1": "test"},
+					Host:     "example.com",
+					Protocol: "https",
+					Error:    "Not Found",
+				},
+			},
+		},
+	}
+
+	// ALB tags set is the same as for API Gateway, so we just copy it over
+	examples["aws:application.load.balancer"] = examples["aws:api.gateway"]
+
+	for trigger, example := range examples {
+		t.Run(trigger, func(t *testing.T) {
+			recorder := instana.NewTestRecorder()
+			tracer := instana.NewTracerWithEverything(&instana.Options{}, recorder)
+
+			sp := tracer.StartSpan("aws.lambda.entry", opentracing.Tags{
+				"lambda.arn":     "lambda-arn-1",
+				"lambda.name":    "test-lambda",
+				"lambda.version": "42",
+				"lambda.trigger": trigger,
+			}, example.Tags)
+			sp.Finish()
+
+			spans := recorder.GetQueuedSpans()
+			assert.Equal(t, 1, len(spans))
+			span := spans[0]
+
+			assert.Equal(t, "aws.lambda.entry", span.Name)
+			assert.Equal(t, example.Expected, span.Data)
+		})
+	}
+}