User:Bináris/Pywikibot cookbook

__NEWSECTIONLINK__

Pywikibot is the ninth wonder of the world, the eighth being MediaWiki itself.

This page is for you, if you
 * already have some experience with Pywikibot and have some vision about its capabilities
 * have some basic knowledge of Python and object-oriented programming
 * want to hack your own scripts
 * are already familiar with Manual:Pywikibot and especially Manual:Pywikibot/Create your own script.

Pywikibot is very flexible and powerful tool to edit Wikipedia or another MediaWiki instance. However, there comes the moment when you feel that something is missing from it, and the Universe calls you to write your own scripts. Don't be afraid, this is not a disease, this is the natural way of personal evolution. Pywikibot is waiting for you: you will find the  directory with a bare , which is ready to host your scripts.

(A personal confession from the creator of this page: I just wanted to use Pywikipedia, as we called it in the old times, then I wanted to slightly modify some of the scripts to better fit to my needs, then I went to the book store and bought my first Python book. So it goes.)

Creating a script

 * Encoding and environment: It is vital that all Python 3 source files MUST be UTF-8 without a BOM. Therefore it is a good idea to forget the bare Notepad of Windows forever, because it has the habit to soil files with BOM. The minimal suggested editor is Notepad++, which is developed for programming purposes and is cross-platform. It has an Encoding menu where you see what I am speaking about, and you may set UTF-8 without BOM as default encoding. Any real programming IDE will do the job properly, e.g. Visual Studio Code is quite popular nowadays. Python has an integrated editor called IDLE, which uses proper encoding, but for some mysterious reason does not show line numbers, so you will suffer a lot from error messages, when you keep trying to find the 148th line of your code.


 * Where to put:  directory is designed to host your scripts. This is a great idea, because this directory will be untouched when you update Pywikibot, and you can easily backup your own work, regarding just this directory.
 * You may also create your own directory structure. If you would like to use other than the default, search for  in , and you will see the solution.

Coding style
Of course, we have PEP 8, Manual:Coding conventions/Python and Manual:Pywikibot/Development/Guidelines. But sometimes we feel like just hacking a small piece of code for ourselves and not bothering the style.

Several times a small piece of temporary code begins to grow beyond our initial expectations, and we have to clean it.

If you'll take my advice, do what you want, but my experience is that it is always worth to code for myself as if I coded for the world.

On the other side, when you use Pywikibot interactively (see below), it is normal to be lazy and use abbreviations and aliases. For example Note that the  alias cannot be used in the second import. It will be useful later, e.g. for.

Beginning and ending
In most cases you see something like this in the very first line of Pywkibot scripts:

or

This is a shebang. If you use a Unix-like system, you know what it is for. If you run your scripts on Windows, you may just omit this line, it does not do anything. But it can be a good idea to use anyway in order someday others want to use your script.

The very last two lines of the scripts also follow a pattern. They usually look like this: This is a good practice in Python. When you run the script directly from command line (that's what we call directory mode), the condition will be true, and the  function will be called. That's where you handle arguments and start the process. On the other side, if you import the script (that is the library mode), the condition evaluates to false, and nothing happens (just the lines on the main level of your script will be executed). Thus you may directly call the function or method you need.

Documentation and help
We have three levels of documentation. As you go forward into understanding Pywikibot, you will become more and more familiar with these levels.
 * 1) Manual:Pywikibot – written by humans for humans. This is recommended for beginners. It also has a "Get help" box.
 * 2) https://doc.wikimedia.org/pywikibot – mostly autogenerated technical documentation with all the fine details you are looking for. Click on   if you use the latest deployed stable version of Pywikibot (this is recommended unless you want to develop the framework itself), and on   if you use the actual version that is still under development. Differences are usually small.
 * 3) The code itself. It is useful if you don't find something in documentation or you want to find working solutions and good practices. You may reach it from the above docs (most classes and methods have a   link) or from your computer.

Basic concepts
Throughout the manual and the documentation we speak about MediaWiki rather than Wikipedia and WikiBase rather than Wikidata beacuse these are the underlying software. You may use Pywikibot on other projects of WikiMedia Foundation, any non-WMF wiki and repository on Internet, even on a MediaWiki or WikiBase instance on your home computer. See the right-hand menu for help.

Testing the framework
Let's try this at Python prompt: Of course, you will have the name of your own bot there if you have set the  properly. Now, what does it mean? This does not mean this is a valid username, even less it is logged in. This does not mean you have reached Wikipedia, neither you have Internet connection. This means that Python is working, Pywikibot is working, and you have set your home wiki and username in. Any string may be there by this point.

If you save the above code to a file called test.py: and run it with, you will get Brghhwsf.