Small simple FPC library for implementing Google OAuth 2.0

This can be used to do XOAUTH2 for sending mail via GMail

• FPC 2.6.4+ (others untested)
• Synapse
• libeay32.dll
• libssl32.dll
• ssleay32.dll

First of all, for your own project you'll need to create your own credentials. (the ones provides here show its own title-header during authentication)

https://developers.google.com/identity/protocols/OpenIDConnect#getcredentials

• Create a project
• Enable the GMail and Google+ Api
• Set the details in "Consent screen"
• Create credentials for a "Installed application"
• And use the Client ID and Client secret in the example application

Currently the provided credentials do work for the test-application.

Note: The sope for composing mail https://www.googleapis.com/auth/gmail.compose is not enhough to mail via smtp. Smtp access requires full mail-access.

• https://developers.google.com/accounts/docs/OAuth2InstalledApp
• https://developers.google.com/oauthplayground/
• https://developers.google.com/accounts/docs/OAuth2
• https://developers.google.com/google-apps/gmail/oauth_overview
• https://developers.google.com/google-apps/calendar/
• http://masashi-k.blogspot.nl/2013/06/sending-mail-with-gmail-using-xoauth2.html

For communication Synapse from Ararat is used. You can download the latest version from https://sourceforge.net/p/synalist/code/HEAD/tree/trunk/ (at the top-right is a "Download snapshot"-button. Put it somewhere and in Lazarus you can choose "Package" > "Open package file". Browse to the folder for synapse and choose laz_synapse.lpk. Extra step is to add the ssl_openssl.pas before compiling for HTTPS access. You don't need to install anything. laz_synapse will now be available as package. You also need the openssl DLLs in your project directory (or search-path). libeay32.dll, libssl32.dll and ssleay32.dll.

• Improve the documentation and comments
• Create a TDataset-like descendant for Calendar and EMail access