[grid] Container existence won't be checked.

Checking for container existence does one more
request to the docker daemon, and in moments of
high usage, this can query the daemon for all
containers unnecessarily. Instead of that, we
handle the response from the docker endpoint
and we log it. Ideally, we are stopping a
container when the user said `driver.quit()`,
so for the user does not really matter if the
container died or not. Logs are enough to
investigate issues.

java/server/src/org/openqa/selenium/docker/Container.java

@@ -20,6 +20,7 @@
 import org.openqa.selenium.internal.Require;
 
 import java.time.Duration;
+import java.util.logging.Level;
 import java.util.logging.Logger;
 
 public class Container {
@@ -46,10 +47,11 @@ public void start() {
   public void stop(Duration timeout) {
     Require.nonNull("Timeout to wait for", timeout);
 
-    if (protocol.exists(id)) {
-      LOG.info("Stopping " + getId());
-
+    LOG.info("Stopping " + getId());
+    try {
       protocol.stopContainer(id, timeout);
+    } catch (RuntimeException e) {
+      LOG.log(Level.WARNING, "Unable to stop container: " + e.getMessage(), e);
     }
   }
 

java/server/src/org/openqa/selenium/docker/DockerProtocol.java

@@ -27,6 +27,5 @@ public interface DockerProtocol {
   Container create(ContainerConfig info);
   void startContainer(ContainerId id) throws DockerException;
   void stopContainer(ContainerId id, Duration timeout) throws DockerException;
-  boolean exists(ContainerId id);
   ContainerInfo inspectContainer(ContainerId id) throws DockerException;
 }

java/server/src/org/openqa/selenium/docker/v1_40/V140Docker.java

@@ -40,7 +40,6 @@ public class V140Docker implements DockerProtocol {
   private final CreateContainer createContainer;
   private final StartContainer startContainer;
   private final StopContainer stopContainer;
-  private final ContainerExists containerExists;
   private final InspectContainer inspectContainer;
 
   public V140Docker(HttpHandler client) {
@@ -51,7 +50,6 @@ public V140Docker(HttpHandler client) {
     createContainer = new CreateContainer(this, client);
     startContainer = new StartContainer(client);
     stopContainer = new StopContainer(client);
-    containerExists = new ContainerExists(client);
     inspectContainer = new InspectContainer(client);
   }
 
@@ -102,15 +100,6 @@ public void startContainer(ContainerId id) throws DockerException {
     startContainer.apply(id);
   }
 
-  @Override
-  public boolean exists(ContainerId id) {
-    Require.nonNull("Container id", id);
-
-    LOG.fine(String.format("Checking whether %s is running", id));
-
-    return containerExists.apply(id);
-  }
-
   @Override
   public void stopContainer(ContainerId id, Duration timeout) throws DockerException {
     Require.nonNull("Container id", id);

java/server/src/org/openqa/selenium/grid/docker/DockerSessionFactory.java

@@ -133,7 +133,8 @@ public Optional<ActiveSession> apply(CreateSessionRequest sessionRequest) {
       attributeMap.put(AttributeKey.LOGGER_CLASS.getKey(),
                        EventAttribute.setValue(this.getClass().getName()));
       LOG.info("Creating container, mapping container port 4444 to " + port);
-      Map<String, String> browserContainerEnvVars = getBrowserContainerEnvVars(sessionRequest.getCapabilities());
+      Map<String, String> browserContainerEnvVars =
+        getBrowserContainerEnvVars(sessionRequest.getCapabilities());
         Container container = docker.create(
           image(browserImage)
             .env(browserContainerEnvVars)
@@ -156,7 +157,9 @@ public Optional<ActiveSession> apply(CreateSessionRequest sessionRequest) {
 
         EXCEPTION.accept(attributeMap, e);
         attributeMap.put(AttributeKey.EXCEPTION_MESSAGE.getKey(),
-                         EventAttribute.setValue("Unable to connect to docker server. Stopping container: " + e.getMessage()));
+                         EventAttribute.setValue(
+                           "Unable to connect to docker server. Stopping container: " +
+                           e.getMessage()));
         span.addEvent(AttributeKey.EXCEPTION_EVENT.getKey(), attributeMap);
 
         container.stop(Duration.ofMinutes(1));