MailGun
How to test MailGun Credential
Mailgun Send with curl
curl -s --user 'api:key-3ax6xnjp29jd6fds4gc373sgvjxteol0' \
https://api.mailgun.net/v3/samples.mailgun.org/messages \
-F from='Excited User <excited@samples.mailgun.org>' \
-F to='devs@mailgun.net' \
-F subject='Hello' \
-F text='Testing some Mailgun awesomeness!'