fix(plc4go): Made the Tracer synchronized

plc4go/pkg/api/cache/PlcConnectionCache_test.go

@@ -456,6 +456,8 @@ func TestPlcConnectionCache_ReturningConnectionWithPingError(t *testing.T) {
 		t.Errorf("Expected %d connections in the cache but got %d", 0, len(cache.connections))
 	}
 
+	// In the connection string, we tell the driver to return an error with
+	// the given message on executing a ping operation.
 	connectionResultChan := cache.GetConnection("simulated://1.2.3.4:42?pingError=hurz&traceEnabled=true")
 	select {
 	case connectResult := <-connectionResultChan:
@@ -484,6 +486,8 @@ func TestPlcConnectionCache_ReturningConnectionWithPingError(t *testing.T) {
 				if traces[3].Operation+"-"+traces[3].Message != "ping-error: hurz" {
 					t.Errorf("Expected '%s' as fourth trace message, but got '%s'", "ping-error: hurz", traces[3])
 				}
+			} else {
+				t.Errorf("Expected a result, but got nil")
 			}
 		}
 	case <-time.After(20 * time.Second):

plc4go/spi/tracer/Tracer.go

@@ -21,6 +21,7 @@ package tracer
 
 import (
 	"fmt"
+	"sync"
 	"time"
 
 	"github.com/apache/plc4x/plc4go/spi/options"
@@ -64,6 +65,7 @@ func NewTracer(connectionId string, _options ...options.WithOption) Tracer {
 type tracer struct {
 	connectionId string
 	traceEntries []TraceEntry
+	m            sync.Mutex
 
 	log zerolog.Logger
 }
@@ -77,24 +79,32 @@ func (t *tracer) SetConnectionId(connectionId string) {
 }
 
 func (t *tracer) ResetTraces() {
+	t.m.Lock()
 	t.traceEntries = []TraceEntry{}
+	t.m.Unlock()
 }
 
 func (t *tracer) GetTraces() []TraceEntry {
-	return t.traceEntries
+	t.m.Lock()
+	entries := t.traceEntries
+	t.m.Unlock()
+	return entries
 }
 
 func (t *tracer) AddTrace(operation string, message string) {
+	t.m.Lock()
 	t.traceEntries = append(t.traceEntries, TraceEntry{
 		Timestamp:     time.Now(),
 		ConnectionId:  t.connectionId,
 		TransactionId: "",
 		Operation:     operation,
 		Message:       message,
 	})
+	t.m.Unlock()
 }
 
 func (t *tracer) AddTransactionalStartTrace(operation string, message string) string {
+	t.m.Lock()
 	transactionId := utils.GenerateId(t.log, 4)
 	t.traceEntries = append(t.traceEntries, TraceEntry{
 		Timestamp:     time.Now(),
@@ -103,17 +113,20 @@ func (t *tracer) AddTransactionalStartTrace(operation string, message string) st
 		Operation:     operation,
 		Message:       message,
 	})
+	t.m.Unlock()
 	return transactionId
 }
 
 func (t *tracer) AddTransactionalTrace(transactionId string, operation string, message string) {
+	t.m.Lock()
 	t.traceEntries = append(t.traceEntries, TraceEntry{
 		Timestamp:     time.Now(),
 		ConnectionId:  t.connectionId,
 		TransactionId: transactionId,
 		Operation:     operation,
 		Message:       message,
 	})
+	t.m.Unlock()
 }
 
 func (t *tracer) FilterTraces(traces []TraceEntry, connectionIdFilter string, transactionIdFilter string, operationFilter string, messageFilter string) []TraceEntry {