Add default wait strategy hook

Author: cristianrgreco

docs/features/containers.md

@@ -582,6 +582,24 @@ class CustomStartedContainer extends AbstractStartedContainer {
 }
 ```
 
+### Default wait strategy for custom containers
+
+Custom containers can define a fallback wait strategy by overriding `getDefaultWaitStrategy`. Testcontainers uses this when the user has not explicitly set a wait strategy and neither the container nor its image defines a health check:
+
+```ts
+import { GenericContainer, Wait, WaitStrategy } from "testcontainers";
+
+class CustomContainer extends GenericContainer {
+  constructor() {
+    super("custom/image:1.0.0");
+  }
+
+  protected override getDefaultWaitStrategy(): WaitStrategy {
+    return Wait.forLogMessage("ready");
+  }
+}
+```
+
 ## Exposing container ports
 
 Specify which container ports you want accessible by the host:

packages/testcontainers/src/generic-container/generic-container.ts

@@ -87,6 +87,8 @@ export class GenericContainer implements TestContainer {
 
   protected containerStarting?(inspectResult: InspectResult, reused: boolean): Promise<void>;
 
+  protected getDefaultWaitStrategy?(): WaitStrategy;
+
   public async start(): Promise<StartedTestContainer> {
     const client = await getContainerRuntimeClient();
     await client.image.pull(this.imageName, {
@@ -132,6 +134,7 @@ export class GenericContainer implements TestContainer {
       waitStrategy,
       healthCheck: this.healthCheck,
       imageNames: [this.imageName.string],
+      defaultWaitStrategy: this.getDefaultWaitStrategy?.(),
     });
   }
 

packages/testcontainers/src/wait-strategies/utils/wait-strategy-selector.test.ts

@@ -136,6 +136,19 @@ describe("wait strategy selector", () => {
     ).resolves.toBeInstanceOf(HostPortWaitStrategy);
   });
 
+  it("should select the default wait strategy when no healthcheck is configured", async () => {
+    const defaultWaitStrategy = Wait.forLogMessage("ready");
+
+    await expect(
+      selectWaitStrategy({
+        client: client({} as ImageInspectInfo),
+        inspectResult: containerInspectResult(),
+        imageNames: ["image:latest"],
+        defaultWaitStrategy,
+      })
+    ).resolves.toBe(defaultWaitStrategy);
+  });
+
   it("should select image healthcheck when container inspect omits healthcheck config", async () => {
     await expect(
       selectWaitStrategy({

packages/testcontainers/src/wait-strategies/utils/wait-strategy-selector.ts

@@ -17,6 +17,7 @@ type WaitStrategySelectorOptions = {
   waitStrategy?: WaitStrategy;
   healthCheck?: HealthCheck;
   imageNames?: string[];
+  defaultWaitStrategy?: WaitStrategy;
 };
 
 export const selectWaitStrategy = async ({
@@ -25,13 +26,14 @@ export const selectWaitStrategy = async ({
   waitStrategy,
   healthCheck,
   imageNames = getImageNames(inspectResult),
+  defaultWaitStrategy = Wait.forListeningPorts(),
 }: WaitStrategySelectorOptions): Promise<WaitStrategy> => {
   if (waitStrategy) return waitStrategy;
   if (hasHealthCheck(healthCheck)) return Wait.forHealthCheck();
   if (hasDisabledHealthCheckConfig(inspectResult)) return Wait.forListeningPorts();
   if (hasHealthCheckConfig(inspectResult) || hasHealthCheckStatus(inspectResult)) return Wait.forHealthCheck();
   if (await imageHasHealthCheck(client, imageNames)) return Wait.forHealthCheck();
-  return Wait.forListeningPorts();
+  return defaultWaitStrategy;
 };
 
 const getImageNames = (inspectResult: ContainerInspectInfo): string[] => {