Export methods to save oauth tokens between sessions

[hurrymaplelad]

I'd like to use this library from a backup script, where I can't approve OAuth access each time.

I've added two methods (setAccessToken and dumpAccessToken) to auth once and save the access token.

I use 'em like this:

const gr = goodreads({
  key: settings.GOODREADS_APP_KEY,
  secret: settings.GOODREADS_APP_SECRET
});
gr.initOAuth();
const oauthUrl = await gr.getRequestToken();
console.log(`open ${oauthUrl}`);
console.log(`then press any key to continue`);
await new Promise(resolve => process.stdin.once('data', resolve));
await gr.getAccessToken();
console.log(gr.dumpAccessToken());

Then in future non-interactive runs:

const gr = goodreads({
  key: settings.GOODREADS_APP_KEY,
  secret: settings.GOODREADS_APP_SECRET
});
gr.initOAuth();
gr.setAccessToken({
  token: settings.GOODREADS_OAUTH_TOKEN,
  secret: settings.GOODREADS_OAUTH_SECRET
});

[mshafer]

+1 to this PR! I have a similar change on my fork, serving the same purpose (saving tokens between sessions).

[Michael-M-Judd]

+1 for this

[baahrens]

Sorry, took me a while. I'm fine with merging this. Could you resolve the conflicts?

[bscott]

@hurrymaplelad Can we get the conflicts resolved? so @baahrens can merge :)