kin-app-server

A backend service for the Kinit App aimed at:

- storing user data (userid, push-token, device-id etc)

- offering spend and earn opportunities for clients

- paying clients via the payment service (https://github.com/kinecosystem/payment-service)

- push messages are sent via rabbit queues to a dedicated Eshu cluster which forwards them to GCM/APNS

All hosts are private in AWS. only the web-server ia accessible via a loadbalancer at port 443. Some internal services reside behind a loadbalancer (eshu, the payment service). There's even a load-balancer for the rabbit cluster (for health-checks).

There's also an additional machine (kinit-app-cron) which runs some cron'd scripts.

There's a simplified environment called stage with a single instace of every service.

General Design

This is a straight-forward flask webapp backed with a Postgress SQL server in AWS. We use redis for syncing some operations. Payments are done asynchronously with the payment service.

• We monitor/alert with datadog/pagerduty
• Refer to the groundcontrol repo for ops data

Prerequisites

Make sure you have Python 3 >=3.6.4. and ansible >= 2.4 you'll need to get the ansible-galaxy deps with

 ansible-galaxy install -r playbooks/requirements.yml

Installation

This server is intended to be deployed on an ubuntu machine with python3. You'll need to tell Ansible to use the python3 interpreter.

run ansible (2.4.2.0) with this command:

ansible-playbook playbooks/kin-app-server.yml -i <public_ip>, -e 'ansible_python_interpreter=/usr/bin/python3'

Configuration

All configurations reside in the config.py.jinj2 file (in kin-app-server/kinappserver/playbooks/roles/kin-app-server/templates), which is processed by Ansible into a config.py file.

By default, the config is set to DEBUG mode, which has some preset values. Production/Stage values must be give in the Ansible role.

To test the service, run the unittests.

make install; make test

note that the tester uses a local, temporary postgress db - it does not mess with prod/stage.

CI

We use travis to run our tests: https://travis-ci.org/kinecosystem/kin-app-server

Running

At the moment, you can run this service with

flask run

You'll probably also need to export the service name, as following:

export FLASK_APP=kinappserver

Creating the db for the fisrt time:

Go into python console and:

 from kinappserver import db

 db.create_all()

 if you add/remove/modify the sqlalchemy defs in the code, you'll want to modify any existing 
 prod/stage DB's as well. this needs to happen manually, unless you want to completely re-create the databases.

StyleSheet

We intend to loosely follow pep8 and suggest you do too. We do not intend to obey the limit on line length.

Plsql client:

install with:

sudo apt-get install postgresql-client

run with:

export PGPASSWORD=<the password>; psql <db url as given by amazon>