restmail is a sendmail-compatible CLI using gmail & outlook rest APIs. It can be used for email automation, notifications and with git send-mail for sharing patches.

restmail requires only minimal authorization scope to send mail. No access to reading or deleting mail is needed.

# install to ~/go/bin ($GOPATH) go install github.com/tonymet/restmail/cmd/restmail@latest 

Initial setup is done once / provider. This configures oauth2 clientID & Secret

[email protected] CLIENT_ID=xxxxxx CLIENT_SECRET=yyyy restmail -configClient -provider gmail -clientId "${CLIENT_ID}" \ -clientSecret "${CLIENT_SECRET}" -f "${FROM}" 

Once provider config is set up above, you need to do the oauth flow through a web browser. Setup is only done once or if the tokens are invalidated.

[email protected] restmail -authorize -provider gmail -f "${FROM}" 

When this is complete, your auth-token & refresh-token are saved and refreshed automatically.

[email protected][email protected][email protected] echo "subject: test subject\n\ntest message" | restmail -f "${FROM}" -provider gmail "${TO}" cc:"${CC}" 

[sendemail] smtpServer = /home/USERNAME/go/bin/restmail smtpServerOption = [email protected] smtpServerOption = -provider smtpServerOption = gmail 

restmail can be run via container with Google Cloud storage

 docker build . -t containermail 

GCS_PREFIX=test/restmail GCS_BUCKET=YOUR_BUCKET 

GCS Perms will load using APP Default Credentials. Be sure to authorize gcloud auth login before proceeding. The user will need role/Storage Object User for saving & loading the tokens

re-run the OAuth Config with -storage gcs. This will save config to your bucket

[email protected] CLIENT_ID=xxxxxx CLIENT_SECRET=yyyy restmail -configClient -storage gcs -provider gmail -clientId "${CLIENT_ID}" \ -clientSecret "${CLIENT_SECRET}" -f "${FROM}" 

re-run the auth step to save the token. this only needs doing once (refresh token will save)

[email protected] restmail -authorize -storage gcs -provider gmail -f "${FROM}" 

You can run the container on cloud run with args -provider $PROVIDER -f $FROM -m "$MESSAGE" $TO_ADDR

• sendgmail & gmail-oauth-tools send mail via sendmail-compatible CLI to google via SMTP