feat: use passport for github, reddit, twitter auth

[sripwoud]

To deploy this, there are a few additional config settings that need to be defined.

Closes #29, closes #50, closes #55

Handle authentication from github, reddit and twitter with passportjs.

• Define a new Auth Router with the following routes:

  Routes

  |route|description|response| |---|---|---| |/auth/github?redirectUrl|Authenticate via Github|Redirects to GH auth page| |/auth/github/callback||redirects to `redirectUrl`| |/auth/reddit|Authenticate via Reddit|Redirects to Reddit auth page| |/auth/reddit/callback||redirects to `redirectUrl`| |/auth/twitter|Authenticate via Twitter|redirects to Twitter auth page| |/auth/twitter/callback||redirects to `redirectUrl`| |/auth/logout|destroys users session (session endpoint not accessible anymore)|`{ payload: 'ok'}`| |/auth/session|returns all the parameters required to join an interep group **only if the user is authenticated**|`{ provider, token, username, reputation }`|

• Define a new auth model table with provider, token, userId columns

Test plan

First make sure you have all the required config settings

Config

``` "ghPat": "obtain from https://github.com/settings/profile", "ghCallbackUrl": "define in https://github.com/organizations/zkitter/settings/applications", "ghClientId": "define in https://github.com/organizations/zkitter/settings/applications", "ghClientSecret": "define in https://github.com/organizations/zkitter/settings/applications", "rdCallbackUrl": "set in https://www.reddit.com/prefs/apps", "rdClientId": "set in https://www.reddit.com/prefs/apps", "rdClientSecret": "set in https://www.reddit.com/prefs/apps", "twCallbackUrl": "obtain from twitter dev dashboard", "twClientId": "obtain from twitter dev dashboard (oauth 2)", "twClientSecret": "obtain from twitter dev dashboard (oauth 2)", "twConsumerKey": "obtain from twitter dev dashboard", "twConsumerSecret": "obtain from twitter dev dashboard", "twBearerToken": "obtain from twitter dev dashboard", "twAccessKey": "obtain from twitter dev dashboard", "twAccessSecret": "obtain from twitter dev dashboard", "rapidAPIKey": "obtain from rapid api dashboard", ```

Then for provider in [github, reddit, twitter], repeat the following steps:

1. Go to
   http://127.0.0.1:3000/auth/<provider>?redirectUrl=http%3A%2F%2F127.0.0.1%3A3000%2Fauth%2Fsession

2. Authorize application

3. You're redirected to /auth/session endpoints that displays a response like:

   {
    payload: {
      token,
      provider,
      username,
      reputation
    }
   }

   You can also manually check that a record was inserted in the auths table

4. Go to http://127.0.0.1:3000/auth/logout You are successfully logged out

   { payload: 'ok' }

5. Go to http://127.0.0.1:3000/auth/session Expected error:

   { "error": "not authenticated" }

6. Start back from step 1 with a different provider

Comments

Let's keep the old (to be legacy) twitter auth endpoints until UI integration confirms that everything works correctly.