title: Do a synchronous http client fetch within an actix thread
body: <p>I have an actix endpoint, and I need to do a synchronous http client fetch to get some results, and return some data. My endpoints cannot use <code>async</code>, so I can't use any <code>.await</code> methods.</p>
  
  <p>I've tried using reqwests blocking client in my endpoint like so:</p>
  
  <pre><code>{ ...
  
    let res = reqwest::blocking::get(&amp;fetch_url)?
      .json::&lt;MyResp&gt;()?;
    ...
  </code></pre>
  
  <p>But it gives me the error:</p>
  
  <pre><code>thread 'main' panicked at 'Cannot start a runtime from within a runtime. This happens because a function (like `block_on`) attempted to block the current thread while the thread is being used to drive asynchronous tasks.', /.cargo/registry/src/github.com-1ecc6299db9ec823/tokio-0.2.9/src/runtime/enter.rs:19:5
  note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace.
  </code></pre>