Which REST operation (GET, PUT, or POST) for validating information?

Question

My users enter a few information fields in an iOS app. This information must be validated on my server, which has a RESTful API. After validation the UI of the iOS app chang

Answer 1

Google proposes use of Custom Methods for REST API

For custom methods, they should use the following generic HTTP mapping:

https://service.name/v1/some/resource/name:customVerb

The reason to use : instead of / to separate the custom verb from the resource name is to support arbitrary paths. For example, undelete a file can map to POST /files/a/long/file/name:undelete

Source: https://cloud.google.com/apis/design/custom_methods

So for validation the URL should be POST /resource:validate