ypcs

This plugin adds new widget ‘Subscribe Google Groups’, which allows visitors to sign up to admin-specified Google Group.
After user as entered her e-mail address and submits the form, plugin (tries to) sends e-mail to GROUPNAME+subscribe@googlegroups.com. Afterwards, Google Groups sends confirmation link to submitter, and when user has clicked the link, she gets added to the group.
Note: If user domain has strict SPF/DKIM policies for e-mail handling, @googlegroups.com might reject their subscription request. In this case user needs to subscribe manually (by sending mail from her e-mail client or by visiting group page.)
Site can have 1-N widgets, each with their own configuration.

Subscribe Google Groups

Add widget(s) for subscribing to admin-specified Google Groups

drcode

This plugin is made to automate some tasks for users of HelloAsso, a platform for handling association memberships, with great customization possibilities.
It uses a Cron job, at the frequency of your choice, to perform : 
* A HelloAsso API call to retrieve your association members’ data, such as Email address, Name, and any other data they provided during sign-in 
* The outputting of that data to different services
For now, the possible outputs are : 
* Google groups : use Google API to add members’ email addresses to the group(s) of your choice 
* Mailchimp : use Mailchimp API to add or update members, including for merge fields and tags 
* WordPress : create WordPress user accounts on your site, and warn your members via automatic email 
* Custom function : execute any local PHP function with the data outputted from the HelloAsso API call
To help you for troubleshooting if necessary, every of these functions have a testing feature directly in the HelloAdherents settings page, and systematically output a response message in a log.txt file.

HelloAdhérents

Retrieve data from HelloAsso and use it to automatically update mailing lists, and more.

Subscribe Google Groups vs HelloAdhérents