To initialize Publish class you need configuration array dedicated for selected service.
Configuartion array should have the following keys:
Facebook application should be set on the page http://developers.facebook.com.
The 'app_key' value should be content of the field 'App ID' displayed in dashboard.
As 'app_secret' value should be set content of the field 'App Secret' displayed in dashboard.
The application should require the following Facebook user permissions: 'email', 'user_friends', 'publish_actions'.
User access token must be obtained after accepting these permissions by user.
Configuartion array should have the following keys:
LinkedIn application should be set on the page https://developer.linkedin.com/.
The 'app_key' value should be content of the field 'API Key' displayed in application details.
As 'app_secret' value should be set content of the field 'Secret Key' displayed in application details.
The application should require the following LinkedIn user permissions: r_fullprofile', 'r_emailaddress', 'rw_nus'.
User access token must be obtained after accepting these permissions by user.
Configuartion array should have the following keys:
Twitter application should be set on the page https://apps.twitter.com/.
Cofiguration values should be set according to fields: 'Consumer Key', 'Consumer Secret', 'Access Token' and 'Access Token Secret' displayed in the tab "Keys and Access Tokens".
Your Twitter application must have set at least 'Read and Write' option in the tab 'Permissions'.