title: Clear a pending authorization for certificate (ACME) after rateLimit error
body: <p>I'm using Let's Encrypt for my site, and I had an error in my cron job that resulted in an error when I attempted to manually renew (<code>$ sudo letsencrypt renew</code>):    </p>
  
  <blockquote>
    <p>Error: urn:acme:error:rateLimited :: There were too many requests of
    a given type :: Error creating new authz :: Too many currently pending
    authorizations.</p>
  </blockquote>
  
  <p>My certificate has already expired so I can't wait the 7 days for it to clear.</p>
  
  <p>The <a href="https://letsencrypt.org/docs/rate-limits/" rel="noreferrer">Let's Encrypt</a> site indicates I can clear one of the pending requests:</p>
  
  <blockquote>
    <p>If you have a large number of pending authorization objects and are
    getting a rate limiting error, you can trigger a validation attempt
    for those authorization objects by submitting a JWS-signed POST to one
    of its challenges, as described in the <a href="https://github.com/ietf-wg-acme/acme/blob/master/draft-ietf-acme-acme.md#responding-to-challenges" rel="noreferrer">ACME spec</a>.</p>
  </blockquote>
  
  <p>I have the logs with the URLs, but I don't understand how to manually send a "JWS-signed POST".</p>
  
  <p>Here's an example of today's that was rejected, from the log:</p>
  
  <pre><code>2017-03-31 06:40:32,180:DEBUG:root:Sending POST request to https://acme-v01.api.letsencrypt.org/acme/new-authz. 
  args: (), kwargs: {
      'data': '{
          "header": {
              "alg": "RS256",
              "jwk": {"e": "AQAB", "kty": "RSA", "n": "srgrg....huXi0sQ"}
          }, 
          "protected": "rsgrgs....ZJIn0", 
          "payload": "srgrg....In0", 
          "signature": "sgggserg....Tc-Q"
      }'
  }
  </code></pre>
  
  <p>How can I do this?</p>