Do not throw when stopping an already stopped container

fixtures/docker-exit-immediately/Dockerfile

@@ -0,0 +1,5 @@
+FROM alpine:3.10
+
+MAINTAINER Cristian Greco
+
+ENTRYPOINT ["echo", "This container will exit immediately."]

src/container.ts

@@ -1,5 +1,6 @@
 import byline from "byline";
 import dockerode, { ContainerInspectInfo } from "dockerode";
+import log from "./logger";
 import { Duration, TemporalUnit } from "node-duration";
 import { Command, ContainerName, ExitCode } from "./docker-client";
 import { Port } from "./port";
@@ -60,9 +61,18 @@ export class DockerodeContainer implements Container {
   }
 
   public stop(options: StopOptions): Promise<void> {
-    return this.container.stop({
-      t: options.timeout.get(TemporalUnit.SECONDS),
-    });
+    return this.container
+      .stop({
+        t: options.timeout.get(TemporalUnit.SECONDS),
+      })
+      .catch((error) => {
+        /* 304 container already stopped */
+        if (error.statusCode === 304) {
+          log.warn(`Container ${this.getId()} already stopped`);
+        } else {
+          throw error;
+        }
+      });
   }
 
   public remove(options: RemoveOptions): Promise<void> {

src/generic-container.test.ts

@@ -317,5 +317,16 @@ describe("GenericContainer", () => {
 
       expect(response.status).toBe(200);
     });
+
+    it("should exit immediately and stop without exception", async () => {
+      const message = "This container will exit immediately.";
+      const context = path.resolve(fixtures, "docker-exit-immediately");
+      const container = await GenericContainer.fromDockerfile(context).build();
+      const startedContainer = await container.withWaitStrategy(Wait.forLogMessage(message)).start();
+
+      await new Promise((res) => setTimeout(res, 1000));
+
+      await startedContainer.stop();
+    });
   });
 });