[exporter/splunkhec] drop empty log events

.chloggen/drop_empty_events.yaml

@@ -0,0 +1,34 @@
+# 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: splunkhecexporter
+
+# A brief description of the change.  Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Drop empty log events
+
+# Mandatory: One or more tracking issues related to the change. You can use the PR number here if no issue exists.
+issues: [34871]
+
+# (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: |
+  Log records with no body are dropped by Splunk on reception
+  as they contain no log message, albeit they may have attributes.
+
+  This PR removes those logs from consideration to be exported.
+
+  This is in tune with the behavior of splunkhecreceiver, which refuses HEC events with no event (#19769)
+
+
+# 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/splunkhecexporter/client.go

@@ -205,6 +205,10 @@ func (c *client) fillLogsBuffer(logs plog.Logs, buf buffer, is iterState) (iterS
 				} else {
 					// Parsing log record to Splunk event.
 					event := mapLogRecordToSplunkEvent(rl.Resource(), logRecord, c.config)
+					if event == nil {
+						// TODO record this drop as a metric
+						continue
+					}
 
 					// JSON encoding event and writing to buffer.
 					var err error

exporter/splunkhecexporter/logdata_to_splunk.go

@@ -24,6 +24,12 @@ const (
 )
 
 func mapLogRecordToSplunkEvent(res pcommon.Resource, lr plog.LogRecord, config *Config) *splunk.Event {
+	body := lr.Body().AsRaw()
+	if body == nil || body == "" {
+		// events with no body are rejected by Splunk.
+		return nil
+	}
+
 	host := unknownHostName
 	source := config.Source
 	sourcetype := config.SourceType
@@ -83,11 +89,6 @@ func mapLogRecordToSplunkEvent(res pcommon.Resource, lr plog.LogRecord, config *
 		return true
 	})
 
-	body := lr.Body().AsRaw()
-	if body == nil {
-		body = ""
-	}
-
 	return &splunk.Event{
 		Time:       nanoTimestampToEpochMilliseconds(lr.Timestamp()),
 		Host:       host,

exporter/splunkhecexporter/logdata_to_splunk_test.go

@@ -187,14 +187,13 @@ func Test_mapLogRecordToSplunkEvent(t *testing.T) {
 				config.SourceType = "sourcetype"
 				return config
 			},
-			wantSplunkEvents: []*splunk.Event{
-				commonLogSplunkEvent("", 0, map[string]any{}, "unknown", "source", "sourcetype"),
-			},
+			wantSplunkEvents: []*splunk.Event{},
 		},
 		{
 			name: "with span and trace id",
 			logRecordFn: func() plog.LogRecord {
 				logRecord := plog.NewLogRecord()
+				logRecord.Body().SetStr("foo")
 				logRecord.SetSpanID([8]byte{0, 0, 0, 0, 0, 0, 0, 50})
 				logRecord.SetTraceID([16]byte{0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 100})
 				return logRecord
@@ -207,7 +206,7 @@ func Test_mapLogRecordToSplunkEvent(t *testing.T) {
 				return config
 			},
 			wantSplunkEvents: func() []*splunk.Event {
-				event := commonLogSplunkEvent("", 0, map[string]any{}, "unknown", "source", "sourcetype")
+				event := commonLogSplunkEvent("foo", 0, map[string]any{}, "unknown", "source", "sourcetype")
 				event.Fields["span_id"] = "0000000000000032"
 				event.Fields["trace_id"] = "00000000000000000000000000000064"
 				return []*splunk.Event{event}
@@ -329,10 +328,7 @@ func Test_mapLogRecordToSplunkEvent(t *testing.T) {
 				config.SourceType = "sourcetype"
 				return config
 			},
-			wantSplunkEvents: []*splunk.Event{
-				commonLogSplunkEvent("", ts, map[string]any{"custom": "custom"},
-					"myhost", "myapp", "myapp-type"),
-			},
+			wantSplunkEvents: []*splunk.Event{},
 		},
 		{
 			name: "with array body",
@@ -449,13 +445,7 @@ func commonLogSplunkEvent(
 
 func Test_emptyLogRecord(t *testing.T) {
 	event := mapLogRecordToSplunkEvent(pcommon.NewResource(), plog.NewLogRecord(), &Config{})
-	assert.Zero(t, event.Time)
-	assert.Equal(t, event.Host, "unknown")
-	assert.Zero(t, event.Source)
-	assert.Zero(t, event.SourceType)
-	assert.Zero(t, event.Index)
-	assert.Equal(t, "", event.Event)
-	assert.Empty(t, event.Fields)
+	assert.Nil(t, event)
 }
 
 func Test_nanoTimestampToEpochMilliseconds(t *testing.T) {