[#123] #EXTEND 'assemblyName: DotNet.Testcontainers; function: ITestc…

…ontainersBuilder'

{Add parameter assignRandomHostPort to bind container ports to random host ports.}

src/DotNet.Testcontainers.Tests/Unit/Linux/Database/MySqlTestcontainerTest.cs

@@ -18,8 +18,7 @@ public async Task ConnectionEstablished()
         {
           Database = "db",
           Username = "mysql",
-          Password = "mysql",
-          Port = 33061
+          Password = "mysql"
         });
 
       // When

src/DotNet.Testcontainers/Core/Builder/ITestcontainersBuilder.cs

@@ -86,8 +86,9 @@ public interface ITestcontainersBuilder<T>
     /// Binds the port of the Testcontainer to the same port of the host machine.
     /// </summary>
     /// <param name="port">Port to bind between Testcontainer and host machine.</param>
+    /// <param name="assignRandomHostPort">If true, Testcontainer will bind the port to a random host port, otherwise the host and container ports are the same.</param>
     /// <returns>A configured instance of <see cref="ITestcontainersBuilder{T}"/>.</returns>
-    ITestcontainersBuilder<T> WithPortBinding(int port);
+    ITestcontainersBuilder<T> WithPortBinding(int port, bool assignRandomHostPort = false);
 
     /// <summary>
     /// Binds the port of the Testcontainer to the specified port of the host machine.
@@ -101,8 +102,9 @@ public interface ITestcontainersBuilder<T>
     /// Binds the port of the Testcontainer to the same port of the host machine.
     /// </summary>
     /// <param name="port">Port to bind between Testcontainer and host machine.</param>
+    /// <param name="assignRandomHostPort">If true, Testcontainer will bind the port to a random host port, otherwise the host and container ports are the same.</param>
     /// <returns>A configured instance of <see cref="ITestcontainersBuilder{T}"/>.</returns>
-    ITestcontainersBuilder<T> WithPortBinding(string port);
+    ITestcontainersBuilder<T> WithPortBinding(string port, bool assignRandomHostPort = false);
 
     /// <summary>
     /// Binds the port of the Testcontainer to the specified port of the host machine.

src/DotNet.Testcontainers/Core/Builder/TestcontainersBuilder.cs

@@ -108,19 +108,21 @@ public ITestcontainersBuilder<T> WithExposedPort(string port)
       });
     }
 
-    public ITestcontainersBuilder<T> WithPortBinding(int port)
+    public ITestcontainersBuilder<T> WithPortBinding(int port, bool assignRandomHostPort = false)
     {
-      return this.WithPortBinding(port, port);
+      var hostPort = assignRandomHostPort ? TestcontainersNetworkService.GetAvailablePort() : port;
+      return this.WithPortBinding(hostPort, port);
     }
 
     public ITestcontainersBuilder<T> WithPortBinding(int hostPort, int containerPort)
     {
       return this.WithPortBinding($"{hostPort}", $"{containerPort}");
     }
 
-    public ITestcontainersBuilder<T> WithPortBinding(string port)
+    public ITestcontainersBuilder<T> WithPortBinding(string port, bool assignRandomHostPort = false)
     {
-      return this.WithPortBinding(port, port);
+      var hostPort = assignRandomHostPort ? $"{TestcontainersNetworkService.GetAvailablePort()}" : port;
+      return this.WithPortBinding(hostPort, port);
     }
 
     public ITestcontainersBuilder<T> WithPortBinding(string hostPort, string containerPort)

src/DotNet.Testcontainers/Core/Builder/TestcontainersNetworkService.cs

@@ -0,0 +1,19 @@
+namespace DotNet.Testcontainers.Core.Builder
+{
+  using System.Net;
+  using System.Net.Sockets;
+
+  public static class TestcontainersNetworkService
+  {
+    private static readonly IPEndPoint DefaultLoopbackEndpoint = new IPEndPoint(IPAddress.Loopback, port: 0);
+
+    public static int GetAvailablePort()
+    {
+      using (var socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp))
+      {
+        socket.Bind(DefaultLoopbackEndpoint);
+        return ((IPEndPoint)socket.LocalEndPoint).Port;
+      }
+    }
+  }
+}

src/DotNet.Testcontainers/Core/Models/TestcontainerConfiguration.cs

@@ -6,13 +6,17 @@ namespace DotNet.Testcontainers.Core.Models
 
   public abstract class TestcontainerConfiguration
   {
-    protected TestcontainerConfiguration(string image, int defaultPort)
+    protected TestcontainerConfiguration(string image, int defaultPort) : this(image, defaultPort, defaultPort)
+    {
+    }
+
+    protected TestcontainerConfiguration(string image, int defaultPort, int port)
     {
       this.Image = image;
 
       this.DefaultPort = defaultPort;
 
-      this.Port = defaultPort;
+      this.Port = port;
     }
 
     public string Image { get; }

src/DotNet.Testcontainers/Core/Models/TestcontainerDatabaseConfiguration.cs

@@ -1,10 +1,11 @@
 namespace DotNet.Testcontainers.Core.Models
 {
+  using DotNet.Testcontainers.Core.Builder;
   using DotNet.Testcontainers.Core.Wait;
 
   public abstract class TestcontainerDatabaseConfiguration : TestcontainerConfiguration
   {
-    protected TestcontainerDatabaseConfiguration(string image, int defaultPort) : base(image, defaultPort)
+    protected TestcontainerDatabaseConfiguration(string image, int defaultPort) : base(image, defaultPort, TestcontainersNetworkService.GetAvailablePort())
     {
     }
 

src/DotNet.Testcontainers/Core/Models/TestcontainerMessageBrokerConfiguration.cs

@@ -1,10 +1,11 @@
 namespace DotNet.Testcontainers.Core.Models
 {
+  using DotNet.Testcontainers.Core.Builder;
   using DotNet.Testcontainers.Core.Wait;
 
   public abstract class TestcontainerMessageBrokerConfiguration : TestcontainerConfiguration
   {
-    protected TestcontainerMessageBrokerConfiguration(string image, int defaultPort) : base(image, defaultPort)
+    protected TestcontainerMessageBrokerConfiguration(string image, int defaultPort) : base(image, defaultPort, TestcontainersNetworkService.GetAvailablePort())
     {
     }