[exporter/datadog] Respect confighttp in trace agent (#34025)

Co-authored-by: Pablo Baeyens <pbaeyens31+github@gmail.com>

.chloggen/ddexp-trace-http.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: "Add a feature gate `exporter.datadogexporter.TraceExportUseCustomHTTPClient` that allows a custom HTTP client to be used in trace export"
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [34025]
+
+# (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 is an experimental feature. By default the feature gate is disabled and trace export uses a default HTTP client."
+
+# 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: []

cmd/otelcontribcol/go.mod

@@ -327,7 +327,7 @@ require (
 	github.com/DataDog/datadog-agent/pkg/remoteconfig/state v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/status/health v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/telemetry v0.56.0-rc.1 // indirect
-	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1 // indirect
+	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1.0.20240711082232-dc70454ece9f // indirect
 	github.com/DataDog/datadog-agent/pkg/util/backoff v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/util/cgroups v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/util/executable v0.56.0-rc.1 // indirect

connector/datadogconnector/go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/DataDog/datadog-agent/comp/otelcol/otlp/components/metricsclient v0.56.0-rc.1
 	github.com/DataDog/datadog-agent/comp/otelcol/otlp/components/statsprocessor v0.56.0-rc.1
 	github.com/DataDog/datadog-agent/pkg/proto v0.56.0-rc.1
-	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1
+	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1.0.20240711082232-dc70454ece9f
 	github.com/DataDog/datadog-go/v5 v5.5.0
 	github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/attributes v0.17.0
 	github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/metrics v0.17.0

exporter/datadogexporter/go.mod

@@ -22,7 +22,7 @@ require (
 	github.com/DataDog/datadog-agent/pkg/logs/status/statusinterface v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/proto v0.56.0-rc.1
 	github.com/DataDog/datadog-agent/pkg/status/health v0.56.0-rc.1 // indirect
-	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1
+	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1.0.20240711082232-dc70454ece9f
 	github.com/DataDog/datadog-agent/pkg/util/startstop v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-api-client-go/v2 v2.27.0
 	github.com/DataDog/datadog-go/v5 v5.5.0

exporter/datadogexporter/integrationtest/go.mod

@@ -70,7 +70,7 @@ require (
 	github.com/DataDog/datadog-agent/pkg/remoteconfig/state v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/status/health v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/telemetry v0.56.0-rc.1 // indirect
-	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1 // indirect
+	github.com/DataDog/datadog-agent/pkg/trace v0.56.0-rc.1.0.20240711082232-dc70454ece9f // indirect
 	github.com/DataDog/datadog-agent/pkg/util/backoff v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/util/cgroups v0.56.0-rc.1 // indirect
 	github.com/DataDog/datadog-agent/pkg/util/executable v0.56.0-rc.1 // indirect

exporter/datadogexporter/traces_exporter.go

@@ -22,6 +22,7 @@ import (
 	"github.com/DataDog/opentelemetry-mapping-go/pkg/otlp/attributes/source"
 	"go.opentelemetry.io/collector/consumer"
 	"go.opentelemetry.io/collector/exporter"
+	"go.opentelemetry.io/collector/featuregate"
 	"go.opentelemetry.io/collector/pdata/pcommon"
 	"go.opentelemetry.io/collector/pdata/ptrace"
 	"go.uber.org/zap"
@@ -33,6 +34,13 @@ import (
 	"github.com/open-telemetry/opentelemetry-collector-contrib/exporter/datadogexporter/internal/scrub"
 )
 
+var traceCustomHTTPFeatureGate = featuregate.GlobalRegistry().MustRegister(
+	"exporter.datadogexporter.TraceExportUseCustomHTTPClient",
+	featuregate.StageAlpha,
+	featuregate.WithRegisterDescription("When enabled, trace export uses the HTTP client from the exporter HTTP configs"),
+	featuregate.WithRegisterFromVersion("v0.105.0"),
+)
+
 type traceExporter struct {
 	params           exporter.Settings
 	cfg              *Config
@@ -212,6 +220,12 @@ func newTraceAgentConfig(ctx context.Context, params exporter.Settings, cfg *Con
 	acfg.PeerTagsAggregation = cfg.Traces.PeerTagsAggregation
 	acfg.PeerTags = cfg.Traces.PeerTags
 	acfg.MaxSenderRetries = 4
+	if traceCustomHTTPFeatureGate.IsEnabled() {
+		params.Logger.Info("Experimental feature: datadog exporter trace export uses a custom HTTP client from the exporter HTTP configs")
+		acfg.HTTPClientFunc = func() *http.Client {
+			return clientutil.NewHTTPClient(cfg.ClientConfig)
+		}
+	}
 	if v := cfg.Traces.flushInterval; v > 0 {
 		acfg.TraceWriter.FlushPeriodSeconds = v
 	}