Add User-Agent to docker client (#7407)

User-Agent will contain `tc-java/<version>`

Author: eddumelendez

core/src/main/java/org/testcontainers/DockerClientFactory.java

@@ -62,11 +62,13 @@ public class DockerClientFactory {
 
     public static final String SESSION_ID = UUID.randomUUID().toString();
 
+    public static final String TESTCONTAINERS_VERSION =
+        DockerClientFactory.class.getPackage().getImplementationVersion();
+
     public static final Map<String, String> DEFAULT_LABELS = markerLabels();
 
     static Map<String, String> markerLabels() {
-        String implementationVersion = DockerClientFactory.class.getPackage().getImplementationVersion();
-        String testcontainersVersion = implementationVersion == null ? "unspecified" : implementationVersion;
+        String testcontainersVersion = TESTCONTAINERS_VERSION == null ? "unspecified" : TESTCONTAINERS_VERSION;
 
         Map<String, String> labels = new HashMap<>();
         labels.put(TESTCONTAINERS_LABEL, "true");

core/src/main/java/org/testcontainers/dockerclient/DockerClientProviderStrategy.java

@@ -39,10 +39,11 @@
 import java.security.UnrecoverableKeyException;
 import java.time.Duration;
 import java.util.ArrayList;
-import java.util.Collections;
 import java.util.Comparator;
+import java.util.HashMap;
 import java.util.HashSet;
 import java.util.List;
+import java.util.Map;
 import java.util.Objects;
 import java.util.Optional;
 import java.util.Set;
@@ -408,14 +409,15 @@ public static DockerClient getClientForConfig(TransportConfig transportConfig) {
         if (configBuilder.build().getApiVersion() == RemoteApiVersion.UNKNOWN_VERSION) {
             configBuilder.withApiVersion(RemoteApiVersion.VERSION_1_32);
         }
+        Map<String, String> headers = new HashMap<>();
+        headers.put("x-tc-sid", DockerClientFactory.SESSION_ID);
+        headers.put("User-Agent", String.format("tc-java/%s", DockerClientFactory.TESTCONTAINERS_VERSION));
+
         return DockerClientImpl.getInstance(
             new AuthDelegatingDockerClientConfig(
                 configBuilder.withDockerHost(transportConfig.getDockerHost().toString()).build()
             ),
-            new HeadersAddingDockerHttpClient(
-                dockerHttpClient,
-                Collections.singletonMap("x-tc-sid", DockerClientFactory.SESSION_ID)
-            )
+            new HeadersAddingDockerHttpClient(dockerHttpClient, headers)
         );
     }