ass=message-fields><thead><tr><th>Field</th><th>Type</th><th>Description</th></tr></thead><tbody><tr id=Rule-match><td><code>match</code></td><td><code>string</code></td><td><p>Required. Match is an attribute based predicate. When Mixer receives a
request it evaluates the match expression and executes all the associated <code>actions</code>
if the match evaluates to true.</p><p>A few example match:</p><ul><li>an empty match evaluates to <code>true</code></li><li><code>true</code>, a boolean literal; a rule 