BuffAlert

BuffAlert allows users to set stock alerts and receive free email when the price they are monitoring is reached. It works using cron for the automation part and iexcloud API for the quote. Each user must subscribe to an iexcloud account and get an personal API key in order not to exceed the limit of requests of the Free plan (all the steps to do so are clearly explained to the user).

➡ Live demo: https://buffalert.xyz
➡ Video demo: https://vimeo.com/757308907

Requirements

flask
flask-session
flask-sqlalchemy
mysql-connector-python
gunicorn
requests
apscheduler
werkzeug
python-dotenv
datetime
calendar

Upcoming updates

• Add more assets: At the moment, BuffAlert works with US stocks only. The next release will allow user to set alerts on commodities, currencies (forex) and crypto-currencies.
• Password recovery: Add the possibility for the user to reset his/her password by sending a email containing a verification token.
• Simultaneous alert checks on cronjob: At the moment the checking of alerts is done one alert at a time. If the number of users becomes high, the check launched every hour by the cronjob will be very long. This version is intended to make cronjob perform each alert check simultaneously. This is possible because each user has his own API key, so each request will be separate.

Development

1. Clone the repository
2. Ensure that in config.py, DEV_MODE is on True and rename ..env file into .env. In .env update database credentials depending on your local setup (you'll have to install and configure mysql if not done already).
3. Install dependencies

pipenv shell # launch virtual environment (if port already in use: `npx kill-port <port>`)
pipenv install # Install dependencies listed in Pipfile

4. Create database

python3 -c 'from cli.db import create'

5. Create tables

python3 -c 'from models import db; db.create_all()'

6. Set emails with Mailtrap

• Create a Mailtrap account
• Go to Dashboard > My inbox (in "Projects" list) > In tab "SMTP Settings" click on Show Credentials > Past values into .env file (MAILTRAP_USERNAME and MAILTRAP_PASSWORD).

7. Run the app

gunicorn app:app

8. Launch alerts cronjob

python3 -c 'from cli.cron import check_alerts'

9. (Optional) Create first user (credentials: test@test.com / test)

python3 -c 'from models import User; User.create("test@test.com", "test")'

Production

We will use Heroku to deploy the app.

1. Ensure that in config.py, DEV_MODE is on False.

2. Create a repository on Heroku

heroku create <app_name>

3. Add a Buildpack for Python:

heroku buildpacks:set heroku/python -a <app_name>

4. Push code to heroku

git init
heroku git:remote -a <app_name>
git add .
git commit -m "First commit"
git push -u heroku master # or: `git push heroku <branch_name>:master`

5. Set database (full tuto)

# Add JawsDB addon
heroku addons:create jawsdb
# Get the db credentials 
heroku config | grep JAWSDB # Returns a string like `mysql://{user}:{password}@{host}:{port}/{database}
# Set the environement variables (these variables will replaces the ones in the .env file):
heroku config:set DB={database}
heroku config:set DB_USER={user}
heroku config:set DB_USER_PASSWORD={password}
heroku config:set DB_HOST={host}

6. Create tables

• Use this command with the previous credentials:

mysql -h {host} -u {user} -p # and enter {password} when prompted

• In the terminal, past the content of the cli/db/buffalert.sql file.
• Verify database:

mysql> SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| abc123def456ghi7   |
| information_schema |
+--------------------+
mysql> USE abc123def456ghi7;
Database changed
mysql> SHOW TABLES;
+----------------------------+
| Tables_in_abc123def456ghi7 |
+----------------------------+
| alert                      |
| stock                      |
| stock_category             |
| user                       |
+----------------------------+

7. Set emails with Mailgun

• Register a domain for 1$ on Namecheap.
• Create an account on Mailgun (don't use Heroku's Mailgun addon). Then go to Upgrade page > Choose the "Foundation Trial" plan (bottom of the page). Enter your credit card details (Pro-tip: always use a single-use virtual card to pay online).
• On Mailgun, go to the Domains page > Click "Add New Domain" button. Enter the domain ou just registered on Namecheap.
• Go to "Sending" on the left-menu > "Domain settings" > Choose your new domain in the top-right selector > Click on "SMTP Credentials" tab. Set the variables as follow, replacing {login} and{password} by the values given by Mailgun:

heroku config:set MAILGUN_SMTP_HOSTNAME=smtp.eu.mailgun.org
heroku config:set MAILGUN_PORT=587
heroku config:set MAILGUN_LOGIN={login}
heroku config:set MAILGUN_PASSWORD={password}

• On the same page, click on "DNS records" tab. In Namecheap Domain List page > click on "Manage" button for your domain > Click on "Advanced DNS" tab. Copy/past here all the DNS records from Mailgun. Check the DNS propagation with tools like this one.

8. Launch flask app and cronjob (set dynos)

# These commands activate the tasks listed in `Procfile` file.
# Launch flask app:
heroku ps:scale web=1
# Launch cronjob on `check_alerts.py':
heroku ps:scale clock=1

9. Visit the app:

heroku info -s | grep web_url | cut -d= -f2 
# And click the link ;)

10. (Optionnal) Set a domain name and add SSL encryption

• Follow this tutorial
• Set up SSL using Cloudflare: Go to "SSL/TLS" page > Choose "Flexible" encryption mode. Then go to "Edge Certificates" page > In the "Edge Certificates box, follow the the instructions to add the TXT records (in "DNS" page). The Status should change to "Active" automatically after a few minutes. In "Edge Certificates" check "Always Use HTTPS" and "Automatic HTTPS Rewrites".

Manage database:

Localy using CLI:

mysql -u <username> -p
# Full MySQL commands list: www.interviewbit.com/blog/mysql-commands

Localy using GUI:

1. Install PhpMyAdmin
2. Go to http://localhost/phpmyadmin

Online (Heroku) using CLI:

heroku config | grep DB
# DB:               abc123
# DB_HOST:          abc123.abc123.us-east-1.rds.amazonaws.com
# DB_USER:          abc123
# DB_USER_PASSWORD: abc123
# ...
mysql -h {DB_HOST} -u {DB_USER} -p # and enter {DB_USER_PASSWORD} when prompted
# Then navigate and do queries in the database: www.interviewbit.com/blog/mysql-commands

Online using GUI:

# Install MySQL Workbench
sudo snap install mysql-workbench-community
# Then add a new connexion with the heroku DBJaws credentials.
# Get them with this command:
heroku config | grep DB

Tips

• Check Heroku logs: heroku logs --tail (full list of the correct timezones here)
• Get Status of working processes on Heroku (dynos): heroku ps
• Edit Heroku logs timezone: heroku config:add TZ="Europe/Paris"
• On dev environement on Linux, access the local database files in: admin:///var/lib/mysql/{db_name} folder

Links

• FLask-SQLAlchemy - Models definition
• FLask-SQLAlchemy - Db Queries syntax
• Theme StartBootstrap