= Sending Email =

The 825gen2 can send emails.

The sendmail and msmtp commands are included in our Yocto Linux build.

{{{
cd /home/root


Create the msmtp config file

nano ~/.msmtprc

defaults
tls on

account gmail
auth on
host smtp.gmail.com
port 587
user wilsonwareapps@gmail.com
from wilsonwareapps@gmail.com

account default : gmail
}}}

Google no longer allows applications to use regular Google login password. 
Create an app specific password in google web portal





Keep a record the generated password
{{{
ueut eapo jrqv eaid
}}}

Create an email

{{{
nano message.txt

From: wilsonwareapps@gmail.com
To: don@wilsonware.com
Subject: Test email from 825

Test 825ARM Variscite

123456
abc
}}}

Send the email

{{{
msmtp -t < message.txt
password for wilsonwareapps@gmail.com at smtp.gmail.com: 
}}}


Enter the app password

How to store password to not require password entry every time email is sent?
(At first tried adding libsecret, but that seems to require gnome-keyring. I added that and a bunch of dependent packages were also added. The keychain seems to be active but msmtp was still prompting for password. Then I learned the password could be added to the config file which is much simpler. Removing gnome-keychain for now since it adds a lot of unnecessary things.)

Password can be added to config file such as:

{{{
nano ~/.msmtprc

defaults
tls on

account gmail
auth on
host smtp.gmail.com
port 587
user wilsonwareapps@gmail.com
from wilsonwareapps@gmail.com
password ueut eapo jrqv eaid

account default : gmail



root@imx8mq-var-dart:~# msmtp -t < message.txt
}}}

E-mail sent successfully with no prompt for password

This could be done from app code using a system call.


How to send file attachments?

msmtp does not have support for file attachments directly. The message must be encoded in mime format.

Update message.txt to add MIME encoding

{{{
nano message.txt

From: wilsonwareapps@gmail.com
To: dwilson@cardet.com
Subject: Test email from 825
MIME-Version: 1.0
Content-Type: multipart/mixed; boundary="MyBoundaryString"


--MyBoundaryString
Content-Type: text/plain
Content-Transfer-Encoding: 7bit

This is a message.

--MyBoundaryString
Content-Type: text/plain; file="file123.txt"
Content-Disposition: attachment; filename="file123.txt"
Content-Transfer-Encoding: base64

}}}


Create attachment file

{{{
nano attachment.txt

This is an attachment
123456
abcdefg
}}}

Use base64 to convert the attachment to base64 encoding:

{{{
base64 attachment.txt > /tmp/attachment
}}}

Now pipe both files to the msmtp command

{{{
cat message.txt /tmp/attachment | msmtp -t
}}}

This successfully sends email with attachment