This section is largely superseded by JSON API for data abstraction classes and VBA API using the Google Apps Script dbab library, but the library discussed below is used by both of these
As a web app, you would access via a POST or a GET, with parameters specified either as url parameters, in the post body of your request, or a mix of both. For example
This API uses another library, through which you can access the DataHandlerRest class.
Almost everything you need is already in the DataHandlerRest class, but you'll need to set up your own version of the web app, so that you can access your own sheets, credentials and databases as yourself. Here's what you need to do.
This is the type of response you will get from the API. Note that if you specify the callback parameter, JSONP will be returned, otherwise you'll get plain JSON.
For more on this, see Database abstraction with google apps script
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