Can't import code from google apps script using API

[michaelsnowden via StackOverflow]

I'm trying to develop a plugin for IntelliJ to let me edit google apps scripts (GAS). The motivation is this. I want my projects to have better version control, refactoring methods, etc.

I think I can leverage the google drive API to do this. Specifically, I want IntelliJ to be able to import, edit, and export GAS to and from my google drive seamlessly.

Here are the steps I followed to try and accomplish this:

I used the developer console to enable the Drive API.

I followed this quickstart guide to create an example apps script project.

1. I created a GAS project titled 'Apps Script Execution API Quickstart Target' with one file named 'Code.gs' in it
2. I deployed it as an API executable

I then read this Java quickstart guide to use the GAS API.

I ran this method to read my example project:

public static void main(String[] args) throws IOException {
    // ID of the script to call. Acquire this from the Apps Script editor,
    // under Publish > Deploy as API executable.
    String scriptId = <my script ID>;
    Script service = getScriptService();

    // Create an execution request object.
    ExecutionRequest request = new ExecutionRequest()
            .setFunction("getFoldersUnderRoot");

    try {
        // Make the API request.
        Operation op =
                service.scripts().run(scriptId, request).execute();

        // Print results of request.
        if (op.getError() != null) {
            // The API executed, but the script returned an error.
            System.out.println(getScriptError(op));
        } else {
            // The result provided by the API needs to be cast into
            // the correct type, based upon what types the Apps
            // Script function returns. Here, the function returns
            // an Apps Script Object with String keys and values,
            // so must be cast into a Java Map (folderSet).
            Map<String, String> folderSet =
                (Map<String, String>)(op.getResponse().get("result"));
            if (folderSet.size() == 0) {
                System.out.println("No folders returned!");
            } else {
                System.out.println("Folders under your root folder:");
                for (String id: folderSet.keySet()) {
                    System.out.printf(
                            "\t%s (%s)\n", folderSet.get(id), id);
                }
            }
        }
    } catch (GoogleJsonResponseException e) {
        // The API encountered a problem before the script was called.
        e.printStackTrace(System.out);
    }
}

It gave me the following error:

com.google.api.client.googleapis.json.GoogleJsonResponseException: 403 Forbidden
Disconnected from the target VM, address: '127.0.0.1:49405', transport: 'socket'
{
  "code" : 403,
  "errors" : [ {
    "domain" : "global",
    "message" : "Project has not enabled the API. Please use Google Developers Console to activate the API for your project.",
    "reason" : "forbidden"
  } ],
  "message" : "Project has not enabled the API. Please use Google Developers Console to activate the API for your project.",
  "status" : "PERMISSION_DENIED"
}
    at com.google.api.client.googleapis.json.GoogleJsonResponseException.from(GoogleJsonResponseException.java:145)
    at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:113)
    at com.google.api.client.googleapis.services.json.AbstractGoogleJsonClientRequest.newExceptionOnError(AbstractGoogleJsonClientRequest.java:40)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest$1.interceptResponse(AbstractGoogleClientRequest.java:321)
    at com.google.api.client.http.HttpRequest.execute(HttpRequest.java:1056)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:419)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.executeUnparsed(AbstractGoogleClientRequest.java:352)
    at com.google.api.client.googleapis.services.AbstractGoogleClientRequest.execute(AbstractGoogleClientRequest.java:469)
    at com.michaelsnowden.gas_plugin.AppsScriptApiQuickstart.main(AppsScriptApiQuickstart.java:197)

The error appears to be this specifically:

Project has not enabled the API. Please use Google Developers Console to activate the API for your project.

I thought I did this earlier though. I'm sure I'm using the right client_secret, the right scopes, and I've been able to use the OAuth playground with my app.

What am I missing to allow me to read scripts from the Google Drive GAS API?

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http://stackoverflow.com/questions/33062657/cant-import-code-from-google-apps-script-using-api