[connector, exporter/datadog] Enable compute_stats_by_span_kind and peer_tags_aggregation by default (open-telemetry#35969)

#### Description
Flip configs `traces::compute_stats_by_span_kind`,
`traces::peer_tags_aggregation` and `traces::peer_service_aggregation`
to true by default

---------

Co-authored-by: Pablo Baeyens <[email protected]>

Author: 2 people

.chloggen/dd-conn-peer-tags.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# 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: datadogconnector
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Flip configs `traces::compute_stats_by_span_kind`, `traces::peer_tags_aggregation` and `traces::peer_service_aggregation` to true by default"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [35969]
+
+# (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: "This enables Datadog APM stats on peer tags by default and is a backwards-compatible change. Read more on https://docs.datadoghq.com/tracing/guide/inferred-service-opt-in/."
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

.chloggen/dd-exp-peer-tags.yaml

@@ -0,0 +1,27 @@
+# Use this changelog template to create an entry for release notes.
+
+# 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: datadogexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: "Flip configs `traces::compute_stats_by_span_kind`, `traces::peer_tags_aggregation` and `traces::peer_service_aggregation` to true by default"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [35969]
+
+# (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: "This enables Datadog APM stats on peer tags by default and is a backwards-compatible change. Read more on https://docs.datadoghq.com/tracing/guide/inferred-service-opt-in/."
+
+# If your change doesn't affect end users or the exported elements of any package,
+# you should instead start your pull request title with [chore] or use the "Skip Changelog" label.
+# Optional: The change log or logs in which this entry should be included.
+# e.g. '[user]' or '[user, api]'
+# Include 'user' if the change is relevant to end users.
+# Include 'api' if there is a change to a library API.
+# Default: '[user]'
+change_logs: []

connector/datadogconnector/factory.go

@@ -45,7 +45,10 @@ func createDefaultConfig() component.Config {
 	return &Config{
 		Traces: TracesConfig{
 			TracesConfig: datadogconfig.TracesConfig{
-				IgnoreResources: []string{},
+				IgnoreResources:        []string{},
+				PeerServiceAggregation: true,
+				PeerTagsAggregation:    true,
+				ComputeStatsBySpanKind: true,
 			},
 
 			TraceBuffer:    1000,

connector/datadogconnector/factory_test.go

@@ -21,7 +21,10 @@ func TestCreateDefaultConfig(t *testing.T) {
 		&Config{
 			Traces: TracesConfig{
 				TracesConfig: datadogconfig.TracesConfig{
-					IgnoreResources: []string{},
+					IgnoreResources:        []string{},
+					PeerServiceAggregation: true,
+					PeerTagsAggregation:    true,
+					ComputeStatsBySpanKind: true,
 				},
 				TraceBuffer:    1000,
 				BucketInterval: 10 * time.Second,

exporter/datadogexporter/integrationtest/integration_test_config.yaml

@@ -21,8 +21,6 @@ processors:
 connectors:
   datadog/connector:
     traces:
-      compute_stats_by_span_kind: true
-      peer_tags_aggregation: true
       peer_tags: ["extra_peer_tag"]
 
 exporters:

pkg/datadog/config/config.go

@@ -340,7 +340,10 @@ func CreateDefaultConfig() component.Config {
 				Endpoint: "https://trace.agent.datadoghq.com",
 			},
 			TracesConfig: TracesConfig{
-				IgnoreResources: []string{},
+				IgnoreResources:        []string{},
+				PeerServiceAggregation: true,
+				PeerTagsAggregation:    true,
+				ComputeStatsBySpanKind: true,
 			},
 		},
 

pkg/datadog/config/config_test.go

@@ -440,7 +440,10 @@ func TestCreateDefaultConfig(t *testing.T) {
 				Endpoint: "https://trace.agent.datadoghq.com",
 			},
 			TracesConfig: TracesConfig{
-				IgnoreResources: []string{},
+				IgnoreResources:        []string{},
+				PeerServiceAggregation: true,
+				PeerTagsAggregation:    true,
+				ComputeStatsBySpanKind: true,
 			},
 		},
 		Logs: LogsConfig{
@@ -510,7 +513,10 @@ func TestLoadConfig(t *testing.T) {
 						Endpoint: "https://trace.agent.datadoghq.com",
 					},
 					TracesConfig: TracesConfig{
-						IgnoreResources: []string{},
+						IgnoreResources:        []string{},
+						PeerServiceAggregation: true,
+						PeerTagsAggregation:    true,
+						ComputeStatsBySpanKind: true,
 					},
 				},
 				Logs: LogsConfig{
@@ -571,6 +577,9 @@ func TestLoadConfig(t *testing.T) {
 						},
 						SpanNameAsResourceName: true,
 						IgnoreResources:        []string{},
+						PeerServiceAggregation: true,
+						PeerTagsAggregation:    true,
+						ComputeStatsBySpanKind: true,
 					},
 					TraceBuffer: 10,
 				},
@@ -630,7 +639,10 @@ func TestLoadConfig(t *testing.T) {
 							"old_name3": "new_name3",
 							"old_name4": "new_name4",
 						},
-						IgnoreResources: []string{},
+						IgnoreResources:        []string{},
+						PeerServiceAggregation: true,
+						PeerTagsAggregation:    true,
+						ComputeStatsBySpanKind: true,
 					},
 				},
 				Logs: LogsConfig{
@@ -684,7 +696,10 @@ func TestLoadConfig(t *testing.T) {
 						Endpoint: "https://trace.agent.datadoghq.com",
 					},
 					TracesConfig: TracesConfig{
-						IgnoreResources: []string{},
+						IgnoreResources:        []string{},
+						ComputeStatsBySpanKind: true,
+						PeerServiceAggregation: true,
+						PeerTagsAggregation:    true,
 					},
 				},
 				Logs: LogsConfig{

pkg/datadog/config/config_warnings_test.go

@@ -137,7 +137,7 @@ func TestPeerTags(t *testing.T) {
 		{
 			name:                  "traces::peer_service_aggregation and traces::peer_tags_aggregation unset",
 			cfgMap:                confmap.New(),
-			expectedPeerTagsValue: false,
+			expectedPeerTagsValue: true,
 		},
 		{
 			name: "traces::peer_tags_aggregation set",