Binding to <code>0</code> assigns you a random port
<div class="remark-highlight"><pre class="language-rust"><code class="language-rust">use std::net::TcpListener;
let listener = TcpListener::bind("localhost:0")?;
println!("{}", listener.local_addr()?.port()); // 51673
</code></pre></div>
<div class="remark-highlight"><pre class="language-go"><code class="language-go">conn, _ := net.Listen("tcp", "localhost:0")
fmt.Println(conn.Addr().String()) // 127.0.0.1:51930
</code></pre></div>
Both Rust and Go frameworks support passing that listener to a HTTP server.

Binding to 0 assigns you a random port
use std::net::TcpListener;
let listener = TcpListener::bind("localhost:0")?;
println!("{}", listener.local_addr()?.port()); // 51673

conn, _ := net.Listen("tcp", "localhost:0")
fmt.Println(conn.Addr().String()) // 127.0.0.1:51930

Both Rust and Go frameworks support passing that listener to a HTTP server.


Bind to a random port