Make findDockerContainer() more robust when containers vanish concurr…

…ently

src/main/java/de/cronn/postgres/snapshot/util/PostgresUtils.java

@@ -23,6 +23,7 @@
 
 import com.github.dockerjava.api.DockerClient;
 import com.github.dockerjava.api.command.InspectContainerResponse;
+import com.github.dockerjava.api.exception.NotFoundException;
 import com.github.dockerjava.api.model.ContainerNetwork;
 
 final class PostgresUtils {
@@ -120,15 +121,20 @@ static ContainerAndNetwork findDockerContainer(String host) {
 
 		return client.listContainersCmd().exec().stream()
 			.map(container -> {
-				InspectContainerResponse inspectContainerResponse = client.inspectContainerCmd(container.getId()).exec();
-				for (ContainerNetwork network : inspectContainerResponse.getNetworkSettings().getNetworks().values()) {
-					if (network.getAliases() != null && network.getAliases().contains(host)) {
-						log.debug("Found Docker container {} with network {}",
-							String.join(", ", container.getNames()), network.getNetworkID());
-						return new ContainerAndNetwork(inspectContainerResponse, network);
+				try {
+					InspectContainerResponse inspectContainerResponse = client.inspectContainerCmd(container.getId()).exec();
+					for (ContainerNetwork network : inspectContainerResponse.getNetworkSettings().getNetworks().values()) {
+						if (network.getAliases() != null && network.getAliases().contains(host)) {
+							log.debug("Found Docker container {} with network {}",
+								String.join(", ", container.getNames()), network.getNetworkID());
+							return new ContainerAndNetwork(inspectContainerResponse, network);
+						}
 					}
+					return null;
+				} catch (NotFoundException e) {
+					log.debug("Docker container '{}' seems to be gone", container.getId(), e);
+					return null;
 				}
-				return null;
 			})
 			.filter(Objects::nonNull)
 			.findFirst()