This repository contains the source code that I demonstrated in my O'Reilly webcast Python Web Development with Flask.
To install and run this application you need:
- Python 2.7 or 3.3+
- virtualenv (not required if you are using Python 3.4)
- git (only to clone this repository)
The commands below install the application and its dependencies:
$ git clone https://github.com/miguelgrinberg/flask-webcast.git
$ cd flask-webcast
$ virtualenv venv
$ . venv/bin/activate
(venv) pip install -r requirements.txt
Note for Python 3.4 users: replace virtualenv with pyvenv.
Note for Microsoft Windows users: replace the virtual environment activation command above with venv\Scripts\activate.
This project is composed of five different applications located in sub-directories named as follows:
- 01-hello-world
- 02-templates
- 03-forms
- 04-database
- 05-structure
To run applications one through four you have to cd into the directory and run the hello.py script in it. For example:
(venv) $ cd 01-hello-world
(venv) $ python hello.py
For the fourth application you need to set up a Mongo database before you can use the application. The connection URL to this database must be stored in a MONGO_URI environment variable. For the live demonstration in the webcast a free cloud based database from http://mongohq.com was used, this is a good alternative if you don't want to go through the effort of installing the database server on your computer.
The fifth application is started by running a script called manage.py. Before you run the application you need to select which configuration to run, which can be development or production. Depending on the selected configuration a second environment variable configures the Mongo database. To run the server in development mode you can run the following commands in a bash shell:
(venv) $ cd 05-structure
(venv) $ FLASK_CONFIG=development MONGO_DEV_URI=http://<your-mongodb-url-here> python manage.py runserver
If you are doing this on Windows then the commands are as follows:
(venv) $ cd 05-structure
(venv) $ set FLASK_CONFIG=development
(venv) $ set MONGO_DEV_URI=http://<your-mongodb-uri-here>
(venv) $ python manage.py runserver
Note that when running the application in production mode the Mongo URL is specified in the MONGO_URI environment variable. Different variables are used for each mode to allow all modes to be configured in the same computer.
Once the server starts you can open http://localhost:5000 in your web browser to see the application in action. To stop the application use Ctrl+C.
See the webcast for a live demonstration.
The fifth version of the application can also run unit tests. The command to run them is as follows:
(venv) $ MONGO_TEST_URI=http://<your-mongodb-test-uri_here> python manage.py test
test_app_exists (test_basics.BasicsTestCase) ... ok
test_app_is_testing (test_basics.BasicsTestCase) ... ok
test_names (test_basics.BasicsTestCase) ... ok
Name Stmts Miss Branch BrMiss Cover Missing
--------------------------------------------------------------
app 10 0 0 0 100%
app.hello 3 0 0 0 100%
app.hello.routes 12 0 4 0 100%
--------------------------------------------------------------
TOTAL 25 0 4 0 100%
----------------------------------------------------------------------
Ran 3 tests in 9.338s
OK
If you are using Windows then the equivalent commands are:
(venv) $ set MONGO_TEST_URI=http://<your-mongodb-test-uri-here>
(venv) $ python manage.py test
It is recommended that you use a different database for testing.
After the tests run you can see a coverage report. This gives you an idea of how much of the application code the tests touch.