[exporter/honeycombmarker] Set user-agent header (open-telemetry#29912)

**Description:** <Describe what has changed.>
<!--Ex. Fixing a bug - Describe the bug and how this fixes the issue.
Ex. Adding a feature - Explain what this achieves.-->

**Link to tracking Issue:** close
open-telemetry#29894

**Testing:** <Describe what testing was performed and which tests were
added.>

**Documentation:** <Describe the documentation added.>

---------

Signed-off-by: Jared Tan <jian.tan@daocloud.io>

.chloggen/honeycombmarker-set-the-User-Agent-header-in-the-outgoing-HTTP-requests.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: exporter/honeycombmarker
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: set the User-Agent header in the outgoing HTTP requests
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [29894]
+
+# (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:
+
+# 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: []

exporter/honeycombmarkerexporter/factory.go

@@ -34,7 +34,7 @@ func createLogsExporter(
 ) (exporter.Logs, error) {
 	cf := cfg.(*Config)
 
-	logsExp, err := newHoneycombLogsExporter(set.TelemetrySettings, cf)
+	logsExp, err := newHoneycombLogsExporter(set, cf)
 	if err != nil {
 		return nil, err
 	}

exporter/honeycombmarkerexporter/logs_exporter.go

@@ -10,9 +10,11 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"runtime"
 	"strings"
 
 	"go.opentelemetry.io/collector/component"
+	"go.opentelemetry.io/collector/exporter"
 	"go.opentelemetry.io/collector/pdata/plog"
 
 	"github.com/open-telemetry/opentelemetry-collector-contrib/internal/filter/filterottl"
@@ -22,32 +24,38 @@ import (
 
 const (
 	defaultDatasetSlug = "__all__"
+	userAgentHeaderKey = "User-Agent"
+	contentType        = "Content-Type"
+	honeycombTeam      = "X-Honeycomb-Team"
 )
 
 type honeycombLogsExporter struct {
-	set     component.TelemetrySettings
-	markers []Marker
-	client  *http.Client
-	config  *Config
+	set             component.TelemetrySettings
+	markers         []Marker
+	client          *http.Client
+	config          *Config
+	userAgentHeader string
 }
 
-func newHoneycombLogsExporter(set component.TelemetrySettings, config *Config) (*honeycombLogsExporter, error) {
+func newHoneycombLogsExporter(set exporter.CreateSettings, config *Config) (*honeycombLogsExporter, error) {
 	if config == nil {
 		return nil, fmt.Errorf("unable to create honeycombLogsExporter without config")
 	}
 
+	telemetrySettings := set.TelemetrySettings
 	for i, m := range config.Markers {
-		matchLogConditions, err := filterottl.NewBoolExprForLog(m.Rules.LogConditions, filterottl.StandardLogFuncs(), ottl.PropagateError, set)
+		matchLogConditions, err := filterottl.NewBoolExprForLog(m.Rules.LogConditions, filterottl.StandardLogFuncs(), ottl.PropagateError, telemetrySettings)
 		if err != nil {
 			return nil, fmt.Errorf("failed to parse log conditions: %w", err)
 		}
 
 		config.Markers[i].Rules.logBoolExpr = matchLogConditions
 	}
 	logsExp := &honeycombLogsExporter{
-		set:     set,
-		markers: config.Markers,
-		config:  config,
+		set:             telemetrySettings,
+		markers:         config.Markers,
+		config:          config,
+		userAgentHeader: fmt.Sprintf("%s/%s (%s/%s)", set.BuildInfo.Description, set.BuildInfo.Version, runtime.GOOS, runtime.GOARCH),
 	}
 	return logsExp, nil
 }
@@ -111,8 +119,9 @@ func (e *honeycombLogsExporter) sendMarker(ctx context.Context, marker Marker, l
 		return err
 	}
 
-	req.Header.Set("Content-Type", "application/json")
-	req.Header.Set("X-Honeycomb-Team", fmt.Sprint(e.config.APIKey))
+	req.Header.Set(contentType, "application/json")
+	req.Header.Set(honeycombTeam, fmt.Sprint(e.config.APIKey))
+	req.Header.Set(userAgentHeaderKey, e.userAgentHeader)
 
 	resp, err := e.client.Do(req)
 	if err != nil {

exporter/honeycombmarkerexporter/logs_exporter_test.go

@@ -8,6 +8,7 @@ import (
 	"encoding/json"
 	"net/http"
 	"net/http/httptest"
+	"strings"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -132,9 +133,13 @@ func TestExportMarkers(t *testing.T) {
 				}
 				assert.Contains(t, req.URL.Path, tt.expectedURL)
 
-				apiKey := req.Header.Get("X-Honeycomb-Team")
+				apiKey := req.Header.Get(honeycombTeam)
 				assert.Equal(t, apiKey, string(tt.config.APIKey))
 
+				userAgent := req.Header.Get(userAgentHeaderKey)
+				assert.NotEmpty(t, userAgent)
+				assert.Equal(t, strings.Contains(userAgent, "OpenTelemetry Collector"), true)
+
 				rw.WriteHeader(http.StatusAccepted)
 			}))
 			defer markerServer.Close()