Boilerplate API on how to structure big Flask applications (includes SQLAlchemy, Docker, nginx)
Flask - SQLAlchemy's declarative base - Docker - custom middleware.
Factories helps in creating many instances of the application. In this project, testing environment creates a new app instance whenever tests are ran.
Blueprints helps to split large application in small modular packages (one would say - similar to django apps
).
The logic is splitted in the following layers:
backend
(persistence layer) - where resides the code to read/write/delete records to disk or databasedomain
(domain layer) - where resides the bussines logic and external api integrations, i/o operations for a blueprintviews
(presentation layer) - knows only about HTTP request
and response
. Its duty is to process a request and pass data to lower layers and to return responses.models
(data model layer) - where all blueprint models are definedThe application tends to use middlewares instead of decorators or custom functions across the project.
application/json
Content-TypeThe project tends to use the framework agnostic extensions over the flask ones, because they are usually wrappers and besides that, they may add additional functionality that you don't actually need (e.g. managers)
Ensures that the application you develop on local machine, behaves exactly in production.
.
├── core # main codebase for the application
│ ├── api # API specific codebase
│ │ ├── common # shared logic used by the application
│ │ │ ├── database.py # common database logic
│ │ │ ├── exceptions.py # custom exception classes
│ │ │ ├── __init__.py
│ │ │ ├── middleware # application middleware
│ │ │ │ ├── __init__.py # define application middlewares
│ │ │ │ ├── request.py # `request` related middleware
│ │ │ │ └── response.py # `response` related middleware
│ │ │ ├── serializers.py # custom defined serializers
│ │ │ └── validation.py # JSON schema validation logic
│ │ ├── conftest.py # pytest configurations and custom fixtures
│ │ ├── foss # flask blueprint
│ │ │ ├── backend.py # logic related to database queries
│ │ │ ├── domain.py # business logic and external integrations
│ │ │ ├── __init__.py # blueprint config
│ │ │ ├── models.py # blueprint models
│ │ │ ├── tests # blueprint tests
│ │ │ │ ├── __init__.py
│ │ │ │ ├── test_unit.py # unit tests
│ │ │ │ ├── test_integration.py # integration tests
│ │ │ │ └── test_models.py # database models tests
│ │ │ └── views.py # logic related to request -> response
│ │ ├── __init__.py # app factory, blueprints, errorhandler and middleware registration
│ │ └── specifications # API specifications, RAML files and JSON schemas
│ │ └── schemas # JSON schemas folder
│ │ └── foss # schemas for a specific blueprint
│ │ ├── create_foss.json # endpoint/view/route schema
│ │ └── update_foss.json # endpoint/view/route schema
│ ├── Dockerfile # Dockerfile for the flask application
│ ├── requirements.txt # application dependencies
│ └── run.py # application creation and running
├── docker-compose.yml # Dockerfiles manager
├── Makefile # set of useful tasks (make `targets`)
├── nginx # nginx docker image related information
│ ├── Dockerfile # Dockerfile for the nginx web server
│ └── sites-enabled
│ └── nginx.conf # nginx configuration
└── README.md
git clone https://github.com/dimmg/flusk.git
make dcompose-start
SSH into the running api
container and start the development server
docker exec -it flusk_api_1 bash
python run.py
By having a running server, execute
docker inspect flusk_nginx_1
where IPAddress
it is the address of the running application.
Change docker-compose.yml
file as follows:
command:
gunicorn -w 1 -b 0.0.0.0:5000 run:wsgi
# tail -f /dev/null
Rebuild the images via
make dcompose-restart
After rebuilding, the gunicorn
wsgi server is running in background.
To get the address of the running web server container run
docker inspect flusk_nginx_1
Migrations are done using the alembic
migration tool.
make db-revision msg=<..message..>
make db-upgrade
make db-upgrade-sql
Note that these are the basic migration commands. To get the most from alembic, use the original $ alembic
runner.