beater/middleware: add trace/log correlation

beater/middleware/log_middleware.go

@@ -21,6 +21,7 @@ import (
 	"github.com/gofrs/uuid"
 
 	"github.com/elastic/beats/libbeat/logp"
+	"go.elastic.co/apm"
 
 	"github.com/elastic/apm-server/beater/headers"
 	"github.com/elastic/apm-server/beater/request"
@@ -34,12 +35,24 @@ func LogMiddleware() Middleware {
 	return func(h request.Handler) (request.Handler, error) {
 
 		return func(c *request.Context) {
-			reqID, err := uuid.NewV4()
-			if err != nil {
-				id := request.IDResponseErrorsInternal
-				logger.Errorw(request.MapResultIDToStatus[id].Keyword, "error", err)
-				c.Result.SetWithError(id, err)
-				c.Write()
+			var reqID, transactionID, traceID string
+			tx := apm.TransactionFromContext(c.Request.Context())
+			if tx != nil {
+				// This request is being traced, grab its IDs to add to logs.
+				traceContext := tx.TraceContext()
+				transactionID = traceContext.Span.String()
+				traceID = traceContext.Trace.String()
+				reqID = transactionID
+			} else {
+				uuid, err := uuid.NewV4()
+				if err != nil {
+					id := request.IDResponseErrorsInternal
+					logger.Errorw(request.MapResultIDToStatus[id].Keyword, "error", err)
+					c.Result.SetWithError(id, err)
+					c.Write()
+					return
+				}
+				reqID = uuid.String()
 			}
 
 			reqLogger := logger.With(
@@ -50,6 +63,13 @@ func LogMiddleware() Middleware {
 				"remote_address", utility.RemoteAddr(c.Request),
 				"user-agent", c.Request.Header.Get(headers.UserAgent))
 
+			if traceID != "" {
+				reqLogger = reqLogger.With(
+					"trace.id", traceID,
+					"transaction.id", transactionID,
+				)
+			}
+
 			c.Logger = reqLogger
 			h(c)
 

beater/middleware/log_middleware_test.go

@@ -22,12 +22,13 @@ import (
 	"testing"
 
 	"github.com/pkg/errors"
-
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/zap/zapcore"
 
 	"github.com/elastic/beats/libbeat/logp"
+	"go.elastic.co/apm"
+	"go.elastic.co/apm/apmtest"
 
 	"github.com/elastic/apm-server/beater/beatertest"
 	"github.com/elastic/apm-server/beater/headers"
@@ -46,6 +47,7 @@ func TestLogMiddleware(t *testing.T) {
 		code          int
 		error         error
 		stacktrace    bool
+		traced        bool
 	}{
 		{
 			name:    "Accepted",
@@ -54,6 +56,14 @@ func TestLogMiddleware(t *testing.T) {
 			handler: beatertest.Handler202,
 			code:    http.StatusAccepted,
 		},
+		{
+			name:    "Traced",
+			message: "request accepted",
+			level:   zapcore.InfoLevel,
+			handler: beatertest.Handler202,
+			code:    http.StatusAccepted,
+			traced:  true,
+		},
 		{
 			name:    "Error",
 			message: "forbidden request",
@@ -87,7 +97,13 @@ func TestLogMiddleware(t *testing.T) {
 		t.Run(tc.name, func(t *testing.T) {
 			c, rec := beatertest.DefaultContextWithResponseRecorder()
 			c.Request.Header.Set(headers.UserAgent, tc.name)
+			if tc.traced {
+				tx := apmtest.DiscardTracer.StartTransaction("name", "type")
+				c.Request = c.Request.WithContext(apm.ContextWithTransaction(c.Request.Context(), tx))
+				defer tx.End()
+			}
 			Apply(LogMiddleware(), tc.handler)(c)
+
 			assert.Equal(t, tc.code, rec.Code)
 			for i, entry := range logp.ObserverLogs().TakeAll() {
 				// expect only one log entry per request
@@ -110,6 +126,14 @@ func TestLogMiddleware(t *testing.T) {
 				if tc.stacktrace {
 					assert.NotZero(t, ec["stacktrace"])
 				}
+				if tc.traced {
+					assert.NotEmpty(t, ec, "trace.id")
+					assert.NotEmpty(t, ec, "transaction.id")
+					assert.Equal(t, ec["request_id"], ec["transaction.id"])
+				} else {
+					assert.NotContains(t, ec, "trace.id")
+					assert.NotContains(t, ec, "transaction.id")
+				}
 			}
 		})
 	}

changelogs/head.asciidoc

@@ -26,4 +26,5 @@ https://github.com/elastic/apm-server/compare/7.5\...master[View commits]
 - Upgrade Go to 1.13.5 {pull}3069[3069].
 - Add experimental support for receiving Jaeger trace data {pull}3129[3129]
 - Upgrade APM Go agent to 1.7.0, and add support for API Key auth for self-instrumentation {pull}3134[3134]
+- Add correlation for server trace/log data {pull}3136[3136]
 

tests/system/test_integration_logging.py

@@ -68,3 +68,24 @@ def test_log_event_size_exceeded(self):
             }, req)
             error = req.get("error")
             assert error.startswith("event exceeded the permitted size."), json.dumps(req)
+
+
+@integration_test
+class LoggingIntegrationTraceCorrelationTest(ElasticTest):
+    config_overrides = {
+        "logging_json": "true",
+        "instrumentation_enabled": "true",
+    }
+
+    def test_trace_ids(self):
+        with open(self.get_transaction_payload_path()) as f:
+            r = requests.post(self.intake_url,
+                              data=f,
+                              headers={'content-type': 'application/x-ndjson'})
+            assert r.status_code == 202, r.status_code
+            intake_request_logs = list(self.logged_requests())
+            assert len(intake_request_logs) == 1, "multiple requests found"
+            req = intake_request_logs[0]
+            self.assertIn("trace.id", req)
+            self.assertIn("transaction.id", req)
+            self.assertEqual(req["transaction.id"], req["request_id"])