This was made without knowledge about official Hangouts integration. You can still use for experimental purposes but for work I recommend using official one.
Just type /hangout
in any channel or direct message to create unique Hangout link.
Warning: for the following steps you can't use Google Apps account. Just log in with @gmail.com account.
- Go to Google Developers Console
- Create Project
- In APIs & auth select APIs and set Calendar API to ON
- In APIs & auth select Credentials and click Create new Client ID
- Set Application Type to Web application
- Set Authorized JavaScript Origins to your Heroku app URL
- Set Authorized Redirect URI to your Heroku app URL with
/oauth2callback
suffix (i.e.http://peaceful-journey-9207.herokuapp.com/oauth2callback
) - Click Create Client ID
- In Heroku go to your app settings and Config Variables section
- Click Reveal Config Vars
- Add CLIENT_ID variable with CLIENT ID value from Google Developers Console
- Add CLIENT_SECRET variable with CLIENT SECRET value from Google Developers Console
- Add REDIRECT_URL variable with REDIRECT URIS value from Google Developers Console
- Go to your Heroku app URL with
/auth
suffix (i.e.http://peaceful-journey-9207.herokuapp.com/auth
)- Accept request
- Copy token into GOOGLE_TOKEN Heroku config variable
- Go to https://api.slack.com/, scroll to Authentication section
- Issue a token for your Slack user
- Copy the token to SLACK_API_TOKEN Heroku config variable
- Save Heroku variables
If you have any questions or improvements, create an issue :)