[exporter/awsxrayexporter]: Add support to string resource attributes (…

…#17503)

Allow string resource attributes to be used in some resource attributes of type slice in the awsxray exporter so that it is possible to set them using the OTEL_RESOURCE_ATTRIBUTES environment variable.

This is a major source of pain among users since it is not possible to set slice resource attributes using OTEL_RESOURCE_ATTRIBUTES open-telemetry/opentelemetry-specification#2857

Signed-off-by: Raphael Silva <rapphil@gmail.com>
Co-authored-by: William Armiros <54150514+willarmiros@users.noreply.github.com>

.chloggen/awsxrayexporter-string-attrs.yaml

@@ -0,0 +1,18 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: 'enhancement'
+
+# The name of the component, or a single word describing the area of concern, (e.g. filelogreceiver)
+component: 'awsxrayexporter'
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: >
+  Add support to string resource attributes of type slice so that it is possible to set those resource attributes using
+  the `OTEL_RESOURCE_ATTRIBUTES` environment variable. Strings are converted to string slices of size 1.
+
+# One or more tracking issues related to the change
+issues: [17503]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

exporter/awsxrayexporter/README.md

@@ -64,7 +64,23 @@ comparable AWS X-Ray Daemon configuration values.
 | `role_arn`             | IAM role to upload segments to a different account.                                |         |
 | `indexed_attributes`   | List of attribute names to be converted to X-Ray annotations.                      |         |
 | `index_all_attributes` | Enable or disable conversion of all OpenTelemetry attributes to X-Ray annotations. | false   |
-| `aws_log_groups`       | List of log group names for cloud watch.                                           |         |
+| `aws_log_groups`       | List of log group names for CloudWatch.                                             | []      |
+
+## Traces and logs correlation
+
+AWS X-Ray can be integrated with CloudWatch Logs to correlate traces with logs. For this integration to work, the X-Ray
+segments must have the AWS Property `cloudwatch_logs` set. This property is set using the AWS X-Ray exporter with the
+following values that are evaluated in this order:
+
+1. `aws.log.group.arns` resource attribute.
+2. `aws.log.group.names` resource attribute.
+3. `aws_log_groups` configuration property.
+
+In the case of multiple values are defined, the value with higher precedence will be used to set the `cloudwatch_logs` AWS Property.
+
+`aws.log.group.arns` and `aws.log.group.names` are slice resource attributes that can be set programmatically.
+Alternatively those resource attributes can be set using the [`OTEL_RESOURCE_ATTRIBUTES` environment variable](https://github.com/open-telemetry/opentelemetry-specification/blob/main/specification/resource/sdk.md#specifying-resource-information-via-an-environment-variable). In this case only a single log group/log group arn can
+be provided as a string rather than a slice.
 
 ## AWS Credential Configuration
 

exporter/awsxrayexporter/internal/translator/aws.go

@@ -117,9 +117,9 @@ func makeAws(attributes map[string]pcommon.Value, resource pcommon.Resource, log
 		case conventions.AttributeAWSECSLaunchtype:
 			launchType = value.Str()
 		case conventions.AttributeAWSLogGroupNames:
-			logGroups = value.Slice()
+			logGroups = normalizeToSlice(value)
 		case conventions.AttributeAWSLogGroupARNs:
-			logGroupArns = value.Slice()
+			logGroupArns = normalizeToSlice(value)
 		}
 		return true
 	})
@@ -268,6 +268,24 @@ func makeAws(attributes map[string]pcommon.Value, resource pcommon.Resource, log
 	return filtered, awsData
 }
 
+// Normalize value to slice.
+// 1. String values are converted to a slice of size 1 so that we can also handle resource
+// attributes that are set using the OTEL_RESOURCE_ATTRIBUTES
+// 2. Slices are kept as they are
+// 3. Other types will result in a empty slice so that we avoid panic.
+func normalizeToSlice(v pcommon.Value) pcommon.Slice {
+	switch v.Type() {
+	case pcommon.ValueTypeStr:
+		s := pcommon.NewSlice()
+		s.AppendEmpty().SetStr(v.Str())
+		return s
+	case pcommon.ValueTypeSlice:
+		return v.Slice()
+	default:
+		return pcommon.NewSlice()
+	}
+}
+
 // Given an array of log group ARNs, create a corresponding amount of LogGroupMetadata objects with log_group and arn
 // populated, or given an array of just log group names, create the LogGroupMetadata objects with arn omitted
 func getLogGroupMetadata(logGroups pcommon.Slice, isArn bool) []awsxray.LogGroupMetadata {

exporter/awsxrayexporter/internal/translator/aws_test.go

@@ -440,6 +440,57 @@ func TestLogGroupsFromArns(t *testing.T) {
 	assert.Contains(t, awsData.CWLogs, cwl2)
 }
 
+// Simulate Log groups being set using OTEL_RESOURCE_ATTRIBUTES
+func TestLogGroupsFromStringResourceAttribute(t *testing.T) {
+	cwl1 := awsxray.LogGroupMetadata{
+		LogGroup: awsxray.String("group1"),
+	}
+
+	attributes := make(map[string]pcommon.Value)
+	resource := pcommon.NewResource()
+	resource.Attributes().PutStr(conventions.AttributeAWSLogGroupNames, "group1")
+
+	filtered, awsData := makeAws(attributes, resource, nil)
+
+	assert.NotNil(t, filtered)
+	assert.NotNil(t, awsData)
+	assert.Equal(t, 1, len(awsData.CWLogs))
+	assert.Contains(t, awsData.CWLogs, cwl1)
+}
+
+func TestLogGroupsInvalidType(t *testing.T) {
+	attributes := make(map[string]pcommon.Value)
+	resource := pcommon.NewResource()
+	resource.Attributes().PutInt(conventions.AttributeAWSLogGroupNames, 1)
+
+	filtered, awsData := makeAws(attributes, resource, nil)
+
+	assert.NotNil(t, filtered)
+	assert.NotNil(t, awsData)
+	assert.Equal(t, 0, len(awsData.CWLogs))
+}
+
+// Simulate Log groups arns being set using OTEL_RESOURCE_ATTRIBUTES
+func TestLogGroupsArnsFromStringResourceAttributes(t *testing.T) {
+	group1 := "arn:aws:logs:us-east-1:123456789123:log-group:group1"
+
+	cwl1 := awsxray.LogGroupMetadata{
+		LogGroup: awsxray.String("group1"),
+		Arn:      awsxray.String(group1),
+	}
+
+	attributes := make(map[string]pcommon.Value)
+	resource := pcommon.NewResource()
+	resource.Attributes().PutStr(conventions.AttributeAWSLogGroupARNs, group1)
+
+	filtered, awsData := makeAws(attributes, resource, nil)
+
+	assert.NotNil(t, filtered)
+	assert.NotNil(t, awsData)
+	assert.Equal(t, 1, len(awsData.CWLogs))
+	assert.Contains(t, awsData.CWLogs, cwl1)
+}
+
 func TestLogGroupsFromConfig(t *testing.T) {
 	cwl1 := awsxray.LogGroupMetadata{
 		LogGroup: awsxray.String("logGroup1"),