Mailservice is an application developed in python using Django, able to send mail to any user and has support to cc and bcc along with subject and body. It also has support to parse CSV file which is list of email addresses, to whom the mail will be sent. I've used ELK stack for the log management, which also indexes the emails stored in DB along with the web requests. There is a periodic task running every 30 minutes, which curates the emails sent in that time period and sends the CSV export to the admins.

• Python 3.6.7
• Django 2.0.7
• elasticsearch 6.6.0
• logstash 6.6.0
• kibana 6.6.0
• crontab 2.3.6
• celery 4.2.1
• redis 3.2.0

• sudo apt update
• sudo apt install python3.6

pip is a package management system for python.

• sudo apt install python3-pip -y
• pip install Django==2.0.7

Virtualenv is a python environment builder. It is used to create isolated python environments.

• pip install virtualenv

Create virtual environment for your project directory followed by commands

• virtualenv -p python3 .
• pip freeze

start by source bin/activate

ends with deactivate

Run migrations

• python manage.py migrate

Run your application in browser run the below command in your terminal and visit localhost:8000

• python manage.py runserver

Elasticsearch requires Java SDK 8 to be installed

• add-apt-repository ppa:webupd8team/java
• apt install -y oracle-java8-set-default

Elasticsearch is used to index data from database for quick search.

• wget https://artifacts.elastic.co/downloads/elasticsearch/elasticsearch-6.6.0.deb
• dpkg -i elasticsearch-6.3.2.deb
• pip install django-elasticsearch-dsl

After installing open /etc/elasticsearch/elasticsearch.yml and edit and uncomment the line below

• network.host: localhost

Now start and run the Elasticsearch service by following commands and visit localhost:9200

• systemctl enable elasticsearch.service
• systemctl start elasticsearch.service

logstash is used to collect, process, and forward events and log messages

• wget https://artifacts.elastic.co/downloads/logstash/logstash-6.6.0.deb
• dpkg -i logstash-6.6.0.deb
• pip install python3-logstash

After installing open /etc/logstash/logstash.yml and change the line below

• http.host: "localhost"

Start and enable Logstash service

• systemctl enable logstash.service
• systemctl start logstash.service

Kibana is used to visualize all the events, data and logs

• wget https://artifacts.elastic.co/downloads/kibana/kibana-6.6.0.deb
• dpkg -i kibana-6.6.0.deb

Next, open /etc/kibana/kibana.yml and update below two lines

• server.host: "localhost"
• elasticsearch.url: "http://localhost:9200"

Start and enable Kibana service and visit localhost:5601 and configure an index pattern

• systemctl enable kibana.service
• systemctl start kibana.service

After configure ELK with your project run below command for logstash and let it run continous

• sudo /usr/share/logstash/bin/logstash -f /path/to/logstash.conf

Celery is a scheduler, that hits off tasks at regular periods. It has worker and beat services. Celery requires redis as a broker

• pip install celery redis

Run worker and beat processes

• celery -A mailservice worker -l info -B
• celery -A mailservice beat -l info -B

• Main landing page of the mailservice is localhost:8000.
• On compose-mail, you can send email to any user with support of cc and bcc.
• The fields email to, cc, and bcc supports comma separated list of emails and has validation in place.
• You can see records of emails in Email model.
• Check log records, to see all request logs, and emails indexed from DB. Remember, you will have to create index pattern before that.
• Run celery -A mailservice worker -l info -B which will send email report every 30 minutes to admins.
• If no email found in last 30 minutes then it won't send report.