How do I publish a random port?

[baautitz]

I'm attempting to dynamically assign a random port to a container upon its creation. I've been experimenting with various configurations, including setting the PortBindings property to null and trying different values for HostPort such as 0, null, an empty string, and "0". However, I haven't been successful in achieving the desired outcome. Here's the snippet of code I've been working with:

CreateContainerParameters containerParameters = new CreateContainerParameters {
    Name = name,
    Image = type,
    HostConfig = new HostConfig {
        PortBindings = new Dictionary<string, IList<PortBinding>> {
            { "25565/tcp", [] }
        }
    }
};

[wfahnestock]

Bump this - anyone have a solution to this? Currently dealing with this issue as well.

[HofmeisterAn]

Simply set the HostPort property of the PortBinding type to an empty string. Like we are doing in Testcontainers.

[mm-ryo]

Simply set the HostPort property of the PortBinding type to an empty string. Like we are doing in Testcontainers.

The empty is not working for this version with Docker.DotNet (3.125.15) Docker version 28.1.1, build 4eba377

var portBinding = new PortBinding
                      {
                          // HostPort = "0/tcp" // working on Docker version <=28.1.1
                          HostPort = string.Empty // working on Docker version >=28.2.2
                      };