Installation¶
Before you begin¶
This tutorial assumes that you have already followed the steps in Installing Pyramid, except do not create a virtual environment or install Pyramid. Thereby you will satisfy the following requirements.
- A Python interpreter is installed on your operating system.
- You've satisfied the Requirements for Installing Packages.
Create directory to contain the project¶
We need a workspace for our project files.
On UNIX¶
$ mkdir ~/pyramidtut
On Windows¶
c:\> mkdir pyramidtut
Create and use a virtual Python environment¶
Next let's create a virtual environment workspace for our project. We will use
the VENV
environment variable instead of the absolute path of the virtual
environment.
On UNIX¶
$ export VENV=~/pyramidtut
$ python3 -m venv $VENV
On Windows¶
c:\> set VENV=c:\pyramidtut
Each version of Python uses different paths, so you will need to adjust the path to the command for your Python version.
Python 2.7:
c:\> c:\Python27\Scripts\virtualenv %VENV%
Python 3.5:
c:\> c:\Python35\Scripts\python -m venv %VENV%
Upgrade pip
and setuptools
in the virtual environment¶
On UNIX¶
$ $VENV/bin/pip install --upgrade pip setuptools
On Windows¶
c:\> %VENV%\Scripts\pip install --upgrade pip setuptools
Install Pyramid into the virtual Python environment¶
On UNIX¶
$ $VENV/bin/pip install "pyramid==1.7.6"
On Windows¶
c:\> %VENV%\Scripts\pip install "pyramid==1.7.6"
Install SQLite3 and its development packages¶
If you used a package manager to install your Python or if you compiled your Python from source, then you must install SQLite3 and its development packages. If you downloaded your Python as an installer from https://www.python.org, then you already have it installed and can skip this step.
If you need to install the SQLite3 packages, then, for example, using
the Debian system and apt-get
, the command would be the following:
$ sudo apt-get install libsqlite3-dev
Change directory to your virtual Python environment¶
Change directory to the pyramidtut
directory, which is both your workspace
and your virtual environment.
On UNIX¶
$ cd pyramidtut
On Windows¶
c:\> cd pyramidtut
Making a project¶
Your next step is to create a project. For this tutorial we will use
the scaffold named alchemy
which generates an application
that uses SQLAlchemy and URL dispatch.
Pyramid supplies a variety of scaffolds to generate sample projects. We
will use pcreate
, a script that comes with Pyramid, to create our project
using a scaffold.
By passing alchemy
into the pcreate
command, the script creates the
files needed to use SQLAlchemy. By passing in our application name
tutorial
, the script inserts that application name into all the required
files. For example, pcreate
creates the initialize_tutorial_db
in the
pyramidtut/bin
directory.
The below instructions assume your current working directory is "pyramidtut".
On UNIX¶
$ $VENV/bin/pcreate -s alchemy tutorial
On Windows¶
c:\pyramidtut> %VENV%\Scripts\pcreate -s alchemy tutorial
Note
If you are using Windows, the alchemy
scaffold may not deal
gracefully with installation into a location that contains spaces in the
path. If you experience startup problems, try putting both the virtual
environment and the project into directories that do not contain spaces in
their paths.
Installing the project in development mode¶
In order to do development on the project easily, you must "register" the
project as a development egg in your workspace using the pip install -e .
command. In order to do so, change directory to the tutorial
directory that
you created in Making a project, and run the pip install -e .
command using the virtual environment Python interpreter.
On UNIX¶
$ cd tutorial
$ $VENV/bin/pip install -e .
On Windows¶
c:\pyramidtut> cd tutorial
c:\pyramidtut\tutorial> %VENV%\Scripts\pip install -e .
The console will show pip
checking for packages and installing missing
packages. Success executing this command will show a line like the following:
Successfully installed Chameleon-2.24 Mako-1.0.4 MarkupSafe-0.23 \
Pygments-2.1.3 SQLAlchemy-1.0.12 pyramid-chameleon-0.3 \
pyramid-debugtoolbar-2.4.2 pyramid-mako-1.0.2 pyramid-tm-0.12.1 \
transaction-1.4.4 tutorial waitress-0.8.10 zope.sqlalchemy-0.7.6
Install testing requirements¶
In order to run tests, we need to install the testing requirements. This is
done through our project's setup.py
file, in the tests_require
and
extras_require
stanzas, and by issuing the command below for your
operating system.
22 23 24 25 26 | tests_require = [
'WebTest >= 1.3.1', # py3 compat
'pytest', # includes virtualenv
'pytest-cov',
]
|
45 46 47 | extras_require={
'testing': tests_require,
},
|
On UNIX¶
$ $VENV/bin/pip install -e ".[testing]"
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\pip install -e ".[testing]"
Run the tests¶
After you've installed the project in development mode as well as the testing requirements, you may run the tests for the project. The following commands provide options to py.test that specify the module for which its tests shall be run, and to run py.test in quiet mode.
On UNIX¶
$ $VENV/bin/py.test -q
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\py.test -q
For a successful test run, you should see output that ends like this:
..
2 passed in 0.44 seconds
Expose test coverage information¶
You can run the py.test
command to see test coverage information. This
runs the tests in the same way that py.test
does, but provides additional
"coverage" information, exposing which lines of your project are covered by the
tests.
We've already installed the pytest-cov
package into our virtual
environment, so we can run the tests with coverage.
On UNIX¶
$ $VENV/bin/py.test --cov --cov-report=term-missing
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\py.test --cov \
--cov-report=term-missing
If successful, you will see output something like this:
======================== test session starts ========================
platform Python 3.5.1, pytest-2.9.1, py-1.4.31, pluggy-0.3.1
rootdir: /Users/stevepiercy/projects/pyramidtut/tutorial, inifile:
plugins: cov-2.2.1
collected 2 items
tutorial/tests.py ..
------------------ coverage: platform Python 3.5.1 ------------------
Name Stmts Miss Cover Missing
----------------------------------------------------------------
tutorial/__init__.py 8 6 25% 7-12
tutorial/models/__init__.py 22 0 100%
tutorial/models/meta.py 5 0 100%
tutorial/models/mymodel.py 8 0 100%
tutorial/routes.py 3 2 33% 2-3
tutorial/scripts/__init__.py 0 0 100%
tutorial/scripts/initializedb.py 26 16 38% 22-25, 29-45
tutorial/views/__init__.py 0 0 100%
tutorial/views/default.py 12 0 100%
tutorial/views/notfound.py 4 2 50% 6-7
----------------------------------------------------------------
TOTAL 88 26 70%
===================== 2 passed in 0.57 seconds ======================
Our package doesn't quite have 100% test coverage.
Test and coverage scaffold defaults¶
Scaffolds include configuration defaults for py.test
and test coverage.
These configuration files are pytest.ini
and .coveragerc
, located at
the root of your package. Without these defaults, we would need to specify the
path to the module on which we want to run tests and coverage.
On UNIX¶
$ $VENV/bin/py.test --cov=tutorial tutorial/tests.py -q
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\py.test --cov=tutorial \
--cov-report=term-missing tutorial\tests.py -q
py.test follows conventions for Python test discovery, and the configuration defaults from the scaffold
tell py.test
where to find the module on which we want to run tests and
coverage.
See also
See py.test's documentation for Usage and Invocations or invoke
py.test -h
to see its full set of options.
Initializing the database¶
We need to use the initialize_tutorial_db
console script to
initialize our database.
Note
The initialize_tutorial_db
command does not perform a migration, but
rather it simply creates missing tables and adds some dummy data. If you
already have a database, you should delete it before running
initialize_tutorial_db
again.
Type the following command, making sure you are still in the tutorial
directory (the directory with a development.ini
in it):
On UNIX¶
$ $VENV/bin/initialize_tutorial_db development.ini
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\initialize_tutorial_db development.ini
The output to your console should be something like this:
2016-05-22 04:03:28,888 INFO [sqlalchemy.engine.base.Engine:1192][MainThread] SELECT CAST('test plain returns' AS VARCHAR(60)) AS anon_1
2016-05-22 04:03:28,888 INFO [sqlalchemy.engine.base.Engine:1193][MainThread] ()
2016-05-22 04:03:28,888 INFO [sqlalchemy.engine.base.Engine:1192][MainThread] SELECT CAST('test unicode returns' AS VARCHAR(60)) AS anon_1
2016-05-22 04:03:28,889 INFO [sqlalchemy.engine.base.Engine:1193][MainThread] ()
2016-05-22 04:03:28,890 INFO [sqlalchemy.engine.base.Engine:1097][MainThread] PRAGMA table_info("models")
2016-05-22 04:03:28,890 INFO [sqlalchemy.engine.base.Engine:1100][MainThread] ()
2016-05-22 04:03:28,892 INFO [sqlalchemy.engine.base.Engine:1097][MainThread]
CREATE TABLE models (
id INTEGER NOT NULL,
name TEXT,
value INTEGER,
CONSTRAINT pk_models PRIMARY KEY (id)
)
2016-05-22 04:03:28,892 INFO [sqlalchemy.engine.base.Engine:1100][MainThread] ()
2016-05-22 04:03:28,893 INFO [sqlalchemy.engine.base.Engine:686][MainThread] COMMIT
2016-05-22 04:03:28,893 INFO [sqlalchemy.engine.base.Engine:1097][MainThread] CREATE UNIQUE INDEX my_index ON models (name)
2016-05-22 04:03:28,893 INFO [sqlalchemy.engine.base.Engine:1100][MainThread] ()
2016-05-22 04:03:28,894 INFO [sqlalchemy.engine.base.Engine:686][MainThread] COMMIT
2016-05-22 04:03:28,896 INFO [sqlalchemy.engine.base.Engine:646][MainThread] BEGIN (implicit)
2016-05-22 04:03:28,897 INFO [sqlalchemy.engine.base.Engine:1097][MainThread] INSERT INTO models (name, value) VALUES (?, ?)
2016-05-22 04:03:28,897 INFO [sqlalchemy.engine.base.Engine:1100][MainThread] ('one', 1)
2016-05-22 04:03:28,898 INFO [sqlalchemy.engine.base.Engine:686][MainThread] COMMIT
Success! You should now have a tutorial.sqlite
file in your current
working directory. This is an SQLite database with a single table defined in it
(models
).
Start the application¶
Start the application.
On UNIX¶
$ $VENV/bin/pserve development.ini --reload
On Windows¶
c:\pyramidtut\tutorial> %VENV%\Scripts\pserve development.ini --reload
Note
Your OS firewall, if any, may pop up a dialog asking for authorization to allow python to accept incoming network connections.
If successful, you will see something like this on your console:
Starting subprocess with file monitor
Starting server in PID 82349.
serving on http://127.0.0.1:6543
This means the server is ready to accept requests.
Visit the application in a browser¶
In a browser, visit http://localhost:6543/. You will see the generated application's default page.
One thing you'll notice is the "debug toolbar" icon on right hand side of the page. You can read more about the purpose of the icon at The Debug Toolbar. It allows you to get information about your application while you develop.
Decisions the alchemy
scaffold has made for you¶
Creating a project using the alchemy
scaffold makes the following
assumptions:
- You are willing to use SQLAlchemy as a database access tool.
- You are willing to use URL dispatch to map URLs to code.
- You want to use zope.sqlalchemy, pyramid_tm, and the transaction packages to scope sessions to requests.
- You want to use pyramid_jinja2 to render your templates. Different templating engines can be used, but we had to choose one to make this tutorial. See Available Add-On Template System Bindings for some options.
Note
Pyramid supports any persistent storage mechanism (e.g., object database or filesystem files). It also supports an additional mechanism to map URLs to code (traversal). However, for the purposes of this tutorial, we'll only be using URL dispatch and SQLAlchemy.