 error code of an API request, the latency of an API request, or the original IP address of a TCP connection. For example:</p><div class="language-yaml highlighter-rouge"><div class="highlight"><pre class="highlight"><code><span class="s">request.path</span><span class="pi">:</span> <span class="s">xyz/abc</span>
<span class="s">request.size</span><span class="pi">:</span> <span class="s">234</span>
<span class="s">request.time</span><span class="pi">:</span> <span class="s">12:34:56.789 04/17/2017</span>
<