<p>I'd like to check that my kubernetes helm chart does not define unused values in <code>values.yaml</code>. This should include any subcharts such that if you've defined <code>subchart.foo.bar: ???</code> in the top-level <code>values.yaml</code> that key is definitely used in the subchart, or possibly as a short-cut mentioned in the <code>subchart/values.yaml</code>.</p>

<p>This is needed to prevent us from shipping bogus "documentation" in the <code>values.yaml</code>, for example if a key in a subchart has been changed or removed.</p>

<p>Ideally there would also be some possibility to report on which subchart values have not been overridden in the top-level chart, though this is less concerning.</p>

<p>Are there any existing tools that can help with this?</p>

<p>AFAIK, there isn't a tool for that. However, it shouldn't be that hard to make one, even using bash. For example, you need to export all key/value pairs like this <code>test.test1.test2</code> and grep for that string recursively in the templates folder. If you want to read yaml using bash, you can install <code>shyaml</code>. If you know how to code in Python, even better.</p>
