feat: Always use Docker's assigned random host port (Ryuk) (#852)

Author: HofmeisterAn

docs/examples/compose.md renamed to docs/examples/dind.md

@@ -1,7 +1,17 @@
-# Compose
+# Running inside another container
 
 ## Docker Desktop
 
+### Sibling containers
+
+If you choose to run your tests in a Docker Wormhole configuration, which involves using sibling containers, it is necessary to mount Docker's raw socket `/var/run/docker.sock.raw`. You find more information and an explanation of the Docker bug in this [comment](https://github.com/docker/for-mac/issues/5588#issuecomment-934600089).
+
+```console
+docker run -v /var/run/docker.sock.raw:/var/run/docker.sock $IMAGE dotnet test
+```
+
+### Compose
+
 To use Docker's Compose tool to build and run a Testcontainers environment in a Docker Desktop Wormhole configuration,
 it is necessary to override Testcontainers' Docker host resolution and set the environment variable `TESTCONTAINERS_HOST_OVERRIDE` to `host.docker.internal`.
 Otherwise, Testcontainers cannot access sibling containers like the Resource Reaper Ryuk or other services running on the Docker host.

mkdocs.yml

@@ -32,7 +32,7 @@ nav:
   - api/wait_strategies.md
   - api/best_practices.md
   - Examples:
-    - examples/compose.md
+    - examples/dind.md
     - examples/aspnet.md
   - Modules:
     - modules/index.md

src/Testcontainers/Builders/ContainerBuilder`3.cs

@@ -182,6 +182,9 @@ public TBuilderEntity WithPortBinding(string port, bool assignRandomHostPort = f
     /// <inheritdoc cref="IContainerBuilder{TBuilderEntity, TContainerEntity}" />
     public TBuilderEntity WithPortBinding(string hostPort, string containerPort)
     {
+      // Remove this together with TestcontainersSettings.ResourceReaperPublicHostPort.
+      hostPort = "0".Equals(hostPort, StringComparison.OrdinalIgnoreCase) ? string.Empty : hostPort;
+
       var portBindings = new Dictionary<string, string> { { containerPort, hostPort } };
       return Clone(new ContainerConfiguration(portBindings: portBindings)).WithExposedPort(containerPort);
     }

src/Testcontainers/Configurations/TestcontainersSettings.cs

@@ -140,6 +140,7 @@ static TestcontainersSettings()
     /// - https://github.com/docker/for-win/issues/11584.
     /// </remarks>
     [NotNull]
+    [Obsolete("The Resource Reaper will use Docker's assigned random host port. This property is no longer supported. For DinD configurations see: https://dotnet.testcontainers.org/examples/dind/.")]
     public static Func<IDockerEndpointAuthenticationConfiguration, ushort> ResourceReaperPublicHostPort { get; set; }
       = _ => 0;
 

src/Testcontainers/Containers/ResourceReaper.cs

@@ -61,7 +61,6 @@ private ResourceReaper(Guid sessionId, IDockerEndpointAuthenticationConfiguratio
         .WithPrivileged(requiresPrivilegedMode)
         .WithAutoRemove(true)
         .WithCleanUp(false)
-        .WithExposedPort(RyukPort)
         .WithPortBinding(TestcontainersSettings.ResourceReaperPublicHostPort.Invoke(dockerEndpointAuthConfig), RyukPort)
         .WithMount(dockerSocket)
         .Build();