Simple shell script to send email using gmail

send-gmail.sh

# Depends on: msmtp, libsecret-tools
#
# Set password:
# secret-tool store --label="msmtp password for jandrews271@gmail.com" service msmtp username jandrews271@gmail.com
#
# Send mail:
# echo "Message Body" | send-gmail myusername recipient@exmaple.com "My Subject"
send-gmail() {
  local user="$1"
  local to="$2"
  local subject="$3"
  local message_body=$(</dev/stdin)
  msmtp \
    --host smtp.gmail.com \
    --port 587 \
    --tls=on \
    --tls-starttls=on \
    --auth=on \
    --user "$user" \
    --from "$user@gmail.com" \
    --passwordeval "secret-tool lookup service msmtp username $user@gmail.com" \
    "$to" << EOF
From: $user@gmail.com
To: $to
Subject: $subject

$message_body
EOF
}

In theory msmtp supports gnome-keyring natively, but it wasn't working for me. I think since I'm not using a full gnome environment some environment variables aren't set correctly. This seems more robust anyway.

You could of course drop the gnome-keyring/libsecret-tools dependency and just replace the passwordeval line with:

--passwordeval 'echo myverysecretpassword' \

In any case, the password can be a google app password (and must be if you've got 2FA enabled).