Here is a walkthrough on how to compile Python packages and
modules, such as those provided by the
Python Standard
Library, so you can distribute your IronPython application as a
set of standalone assemblies. If you just want to use the Python
Standard Library without compiling parts of it into your
application then you can add the path to the standard library as
described in a previous post on
using the Python Standard Library.
Prerequisites
You will need to have SharpDevelop 3.2 and Python 2.6 installed
on your machine. These can be downloaded from the following
locations.
Python Modules Included with IronPython
Before you start compiling a Python module or package into your
application you should check whether it is already included with
IronPython or whether you can use the .NET framework instead. A lot
of the Python Standard
Library modules are already included with IronPython. You can
see which ones by using
Reflector
to look at IronPython.dll and IronPython.Modules.dll. Open these
assemblies in Reflector, right click and select Disassemble. In the
screenshot below the modules that are included with IronPython are
defined by the PythonModule attribute.
Alternatively you can use the
IronPython Modules Reader application to list all the
available modules in IronPython.
If you need to use one of the modules provided by IronPython
then add a reference to IronPython and IronPython.Modules in your
project and then import the module in the normal way:
import cmath
Compiling a Python Module
Now we will look at writing a simple IronPython application that
reads in a zip file using the zipfile module from the Python
standard library. Our application will read the names of all the
files in the zip file and display them in the console window. The
code is shown below.
import zipfile
file = zipfile.ZipFile("test.zip", "r")
for name in file.namelist():
print name
Now if you create a python console project with SharpDevelop,
copy the code above into the Program.py file, compile and run the
program you will get an error saying "No module called
zipfile". To fix this problem you can add the zipfile.py file
from the Python standard library directly into your project. Simply
right click your project, select Add Existing Item and browse to
the zipfile in the python libs folder (e.g. C:\Python26\lib). If
you compile your program again and run it you will get an error
about a different module. The zipfile module depends on 13 other
modules from the standard library. With a bit of trial and error
you can work out which modules are needed. After adding these
dependent modules to your project you will have a set of assemblies
that do not require the Python Standard library to be installed.
The full code for the zip file reader application can be
downloaded from the
Zip File Reader link at the end of this post.
Compiling a Python Package
A Python module consists of a single file (e.g. zipfile.py). A
Python package is a set of files inside a subdirectory. Compiling a
package into your application cannot be done simply by including
the files directly in your project. Instead you must compile the
package files into a separate class library assembly. As an example
we will look at using the json package. We will create a simple
application that creates a json string from a dictionary. The code
is shown below.
import json
address = {}
address["street"] = "24 22nd Street"
address["city"] = "New York"
address["state"] = "NY"
address["postCode"] = "10021"
person = {}
person["firstName"] = "John"
person["lastName"] = "Smith"
person["age"] = 20
person["address"] = address
print json.dumps(person)
Now to use the json package from our application we need to
create a python class library project. Then we need to add all the
files from the json package into this project and compile it.
Finally in our Json Writer project we need to add a reference to
this class library. The screenshot below shows the contents of the
two projects.
Now this is not quite enough since the json package depends on
several modules in the standard library. So now we add these to the
json class library project. After adding these modules the json
class library project should then contain the files as shown in the
screenshot below.
You should now be able to compile and run your Json Writer
application. The Json Writer application can now be distributed as
a set of assemblies without needing the Python Standard Library to
be installed.
The full code for the Json Writer application can be downloaded
from the
Json Writer link at the end of this post.
Finally here is a link to the
license FAQ for Python and Python Standard Library that should
be checked before you include the standard library in your
application.
Downloads