energylifechase.blogg.se - Install flask for mac osx

#Install flask for mac osx how to
#Install flask for mac osx mac os x
#Install flask for mac osx install
#Install flask for mac osx software

(flask_hello_world) $ export FLASK_DEBUG=1 (flask_hello_world) $ export FLASK_APP=run.py Also we’ll enable debugging to automatically restart the server to reload any changes we make.

#Install flask for mac osx how to

Our simple application is now complete, but before running it we need to tell Flask how to import it by setting a FLASK_APP environment variable. Here is what the directory structure should look like at this point.

Define the application instance and import it.

To complete this simple application, create a top-level Python script to define the Flask application instance.

If the browser requests either of the associated urls / or /index Flask is going to invoke the index function and pass the return value to the browser as a response. The decorator creates the association between the given url and the function. The view function simply returns a “Hello World” string.

Add the following view function to the new routes.py file.

The routes don’t exist yet, so let’s create it next.Ĭreate a routes module $ (flask_hello_world) $ touch app/routes.py

Notice the bottom import, it is a workaround to circular imports, a common problem with Flask applications. Flask uses the location of the module passed here as a starting point when it needs to load associated resources such as template files. The name variable passed to the Flask class is a Python predefined variable, which is set to the name of the module in which it is used. The script above simply creates the application object as an instance of class Flask imported from the Flask package. # app/_init_.py: Flask application instance

Add the following to the init.py in the app package.

When you import a package, the init.py executes and defines what symbols the package exposes to the internet.

In Python, a sub-directory that includes an init.py file is considered a package. $ (flask_hello_world) $ touch app/_init_.py

#Install flask for mac osx install

$ (flask_hello_world) $ pip install flask This is not necessary but I like following this pattern as it allows me to remember the name of the virtual environment my application will be running in.

Notice the virtualenv is named the same as the project we are going to be working on. Here is a nice Vim cheatsheetĬreate and activate a new virtual environment $ mkdir flask_hello_world Hit the esc key on your keyboard to exit insert mode or abort the current command and :q! to close file and abandon changes, use the :wq keys to save your changes.Source /usr/local/bin/virtualenvwrapper.sh bash_profile with the following environment variablesĮxport VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/python3Įxport VIRTUALENVWRAPPER_VIRTUALENV=/usr/local/bin/virtualenv You might run into the following error after installing virtualenvwrapper $ workon Let’s install it $ pip3 install virtualenvwrapper These extensions include wrappers fro creating, deleting and managing our development workflow.įor example with only virtualenv to activate a virtual environment you would need the following command. $ pip install virtualenvĪ set of extensions for virtualenv. If you install both libraries into your host python you would end up with conflicts. For instance you have two projects and one requires version 1 of some library, but the other requires version 2 of the same library. The problem being addressed is dependencies and versions of those dependencies. $ brew install python3Ĭheck the Python version $ python -versionĪ tool to create isolated Python environments.

#Install flask for mac osx mac os x

Mac OS X comes with Python 2 installed but this tutorial uses Python 3.Install it with Homebrew.

#Install flask for mac osx software

It’s also possible to build scalable and secure web apps with Flask Prerequisites HomebrewĪ free and open-source software package management system that simplifies the installation of software on Apple’s Mac OS operating system and Linux. It’s great for beginners because it is easy to set up, actively supported by the community, well documented and simple and minimalistic. Flask is a simple, easy to use microframework for Python.