e <code>$out.&lt;field name of the OutputTemplate&gt;</code> syntax.</p><table class="message-fields"><thead><tr><th>Field</th><th>Type</th><th>Description</th></tr></thead><tbody><tr id="OutputTemplate.source_pod_ip"><td><code>sourcePodIp</code></td><td><code><a href="/v0.5/docs/reference/config/mixer/istio.mixer.v1.template.html#IPAddress">istio.mixer.v1.template.IPAddress</a></code></td><td><p>Refers to source pod ip address. attribute<em>bindings can refer to this field using $out.source</em>pod_ip</p><