I set up an interactive python environment in an application. I can input commands and they will execute inside it, having access to the variables that live there.
The problem is that I coded a half-assed editor that allows only that. It doesn't have command history, code completion etc, because I didn't code a full IDE. However, I would like to be able to write code in that environment with a fancy editor.
The way I think it can work out is that an editor will have an interface/protocol for remote python sessions, and I will just have to implement a server in my application (instead of the simple editor) and be able to connect and run code.
I can implement any interface or protocol that I have to, but I can't find an IDE that has such a protocol defined (or an easy way to plug an extension that will serve as the client side).
Essentially, I want a python editor that has an option to call a function x whenever a command (can be multiline) finished typing, and another function y when an autocomplete request occurs.
I checked out some editors but couldn't find such a feature. Does anyone know of such a thing? It actually doesn't have to be a python editor, just support the hooks that i need.
Thanks!
Did you try integrating PyCrust into your application? See this SO question
Embedding a Python shell inside a Python program
rpyc sounds like something which could be useful to you. rpyc added support for IronPython in their latest release. PyScripter supports rpyc. Maybe this is the combo you are looking for?
Related
I'm using Linux Eclipse (pydev) as IDE to develop python scripts that are launched by an application written in C++. I can debug the python script without problems in the IDE, but the environment is not real (the C++ program sends and receives messages through the stdin/stdout and it's a complex communication channel that I can't fully reproduce writing the messages by hand).
Until now I was using log messages to debug (poor man's debug) but it's getting too complex. When I do something similar in PHP I can just leave xdebug listening and add breakpoints in Netbeans. Very neat and easy. Is it possible to do something like that in Python 3.X (with Eclipse or other IDE)?
NOTE: I know there is a Pydev / Attach to Process functionality, but it doesn't work. Always fails to attach.
NOTE2: There is also a built-in "breakpoint()" in Python 3.7 but it links to a debugger and if also fails, the IDE never gets the control.
After some research, this is the best option I have found. Without any other solution provided, I post it just in case anyone has the same problem.
Python has an integrated debugger: pdb. It works as a module and it doesn't allow to use it if you don't have the window control (i.e. you launch the script).
To solve this there are some coders that have created modules that add a layer on pdb. I have tried some and the most easy and still visual interesting is rpudb (but have a look also to this).
To install it:
pip3 install https://github.com/msbrogli/rpudb/archive/master.zip
(if you install it using the pip3 install rpudb command it will install an old version only valid for python 2)
Then, you use it just adding an import and a function call:
import rpudb
.....
rpudb.set_trace('127.0.0.1', 4444)
.....
Launch the program and it will stop in the set_trace call. To debug it (and continue) open a terminal and launch a telnet like this:
telnet 127.0.0.1 4444
You will have a visual debugger in front of you with the advantage that you can not only debug local programs, but also remote (just change the IP).
I was able to attach PyCharm to a running python process and use break points using PyCharm attach to process
I created a bash script which exec a python script, should work the same with C++
I've noticed that some programs (e.g. hg) allow the user to tab-complete specific parts of the command. For example, if, in an hg repository working directory, I type:
hg qpush --move b8<TAB>
It will try to complete the command with any mercurial patches in my patch queue that start with "b8".
What I'd like to do is imitate this behavior in my program. That is, I have a series of commands that depend on files within a certain directory, and I'd like to be able to provide tab completion in the shell. Is there an API for providing this on Ubuntu Linux (preferably using python, as that's what my script is written in)?
To do this, you need to write tab-completion modules for your shell. The default shell in most Linux distributions is bash, so you should write a completion script (typically a shell script). Once you've written your script, add it to /etc/bash_completion.d/. This should be distributed with your program (for Linux distributions, included in the package).
Debian Administration has a guide for writing your completion scripts. For using completion on a Mac, see https://trac.macports.org/wiki/howto/bash-completion.
For examples of completion files, take a look at the bash-completion project from Debian (also on Github). See also https://unix.stackexchange.com/questions/4738/an-easy-bash-completion-tutorial.
If you use zsh, hack.augusto linked to the documentation for writing completions.
This is what the readline module is for.
Actually, readline is a common C library so it has bindings in many languages. And I can say, I've had tons of fun with it.
Enjoy B)
You might want to try the zsh shell, it has a great completion system with support for tons of applications.
The completion system is written with the shell language, but if you really want to use python you can run the interpreter from inside your completion function. The down side it that if you want to write completion for your own software, you will need to do some reading (user manual and the manpage for instance).
Take a look at the source of the 'cmd' module in the Python library. It supports command completion.
Is there a way to execute a file but still be able to call the variables? This would help immensely in learning Python, since I could set up many different "practice" scripts and then use the console to try and modify the code to see what happens.
I think the technical question would be "How can I populate a namespace in Python in Eclipse and leave it open to interactions in the console?
Below is a screenshot showing what I'm trying to do, define a (as 1) in the editor, and then press "ctrl-alt-enter" to run the file in the console, and then call the variable from the console.
[Screenshot of Eclipse]
You should be able to add a debugging breakpoint at the end of code you are executing and inspect variables using a good editor.
In general, you should be able to run simple scripts right inside a python interpreter. Or online if you wish to: http://www.datamech.com/devan/trypython/trypython.py
Try setting up a REPL (read-eval-print) environment using your favorite editor. For instance, emacs has good support for doing such tasks.
How can you save functions/ classes you've writing in a python interactive session to a file? Specifically, is there a way in pydev / eclipse's interactive session (on a mac) to do this?
I just started learning python - and am enjoying using the interpreter's interactive session for testing and playing with modules I've written. However, I find myself writing functions in the interpreter, which I think, oh it would be cool to save that to my script files. How do I do this?
I tried:
import pickle
pickle.dump(my_function, open("output.p", "w"))
But it seems to be more of a binary serialization, or at least nothing that I could copy and paste into my code...
Are there ways to see the code behind classes & functions I've defined in the interpreter? And then copy them out of the interpreter?
Update:
Ok, here's what I've learned so far:
I missed the easiest of all - PyDev's interactive session in eclipse allows you to right click and save your session. Still have to remove >>>'s, but gets the job done.
IPython is apparently the way to go to do this.
How to save a Python interactive session? has more details.
The best environment for interactive coding sessions has to be IPython, in my opinion. It's built on and extends the basic Python interpreter with a lot of magic, including history. For example, you can issue the command %logstart to dump all subsequent input to a file, which still needs to be edited afterward before it will be a script, but gives you a lot to work with.
When installing IPython, don't forget pyreadline.
In general, however, it is best to write code in an IDE and then run it. IPython helps here as well. If you write and save the script, then use the IPython "run" command to run it, the entire global namespace of the script will be available for inspection in your IPython session. Additionally, you can use the -d argument to run to trigger the pdb debugger immediately on any unhandled exception.
If you're more of a straightlaced IDE and debugger kind of guy, then the easiest and best lightweight environment has to be PyScripter.
I think the answer is to change your workflow.
What I do is write my functions in an editor (emacs), and then press a key combination (Ctrl-c Ctrl-e) to send the region of text to the (i)python interpreter.
That way I can save the function if I want, and also play with it in an interpreter.
Emacs is central to how I do it, but I'm sure there must be similar approaches with many editors (vim, gedit, etc) and IDEs.
PS. Finding a good editor is crucial when working with Python. The editor must be able to move blocks of code to the left and right easily, or the whitespace issue becomes too onerous.
I dislike typing blocks of code in the python interpreter because it doesn't allow me to shift blocks easily. You'll like Python even more when you find the right editor.
You can setup a python history file which stores everything you type into the interpreter.
Here's how:
http://docs.python.org/tutorial/interactive.html
I think it can't be done.
Python can perform instrospection with the inspect module, but the inspect.getsource function won't work without a source file.
This may sound strange, but I need a better way to build python scripts than opening a file with nano/vi, change something, quit the editor, and type in python script.py, over and over again.
I need to build the script on a webserver without any gui. Any ideas how can I improve my workflow?
put this line in your .vimrc file:
:map <F2> :w\|!python %<CR>
now hitting <F2> will save and run your python script
You should give the screen utility a look. While it's not an IDE it is some kind of window manager on the terminal -- i.e. you can have multiple windows and switch between them, which makes especially tasks like this much easier.
You can execute shell commands from within vim.
Using emacs with python-mode you can execute the script with C-c C-c
you can try ipython. using its edit command, it will bring up your editor (nano/vim/etc), you write your script, and then on exiting you're returned to the ipython prompt and the script is automatically executed.
When working with Vim on the console, I have found that using "tabs" in Vim, instead of having multiple Vim instances suspended in the background, makes handling multiple files in Vim more efficient. It takes a bit of getting used to, but it works really well.
You could run XVNC over ssh, which is actually passably responsive for doing this sort of thing and gets you a windowing GUI. I've done this quite effectively over really asthmatic Jetstart DSL services in New Zealand (128K up/ 128K down =8^P) and it's certainly responsive enough for gvim and xterm windows. Another option would be screen, which lets you have multiple textual sessions open and switch between them.
There are actually 2 questions. First is polling for a console IDE for python and the second is a better dev/test/deploy workflow.
For while there are many ways you can write python code in the console, I find a combination of screen, vim and python/ipython is the best as they are usually available on most servers. If you are doing long sessions, I find emacs + python-mode typically involves less typing.
For a better workflow, I would suggest setting up a development environment. You can easily setup a Linux VM on your desktop/laptop easily these days - there isn't a excuse not to even if it's for hobby projects. That opens up a much larger selection of IDEs available to you, such as:
GUI versions of VI and friends
Remote file editing with tramp and testing locally with python-mode inside Emacs
http://www.netbeans.org
and of course http://eclipse.org with the PyDev plugin
I would also setup a SCM to keep track of changes so that you do
better QA and use it to deploy tested changes onto the server.
For example I use Mercurial for my pet projects and I simply tag my repo when it's ready and update the production server to the tag when I deploy. On the devbox, I do:
(hack hack hack, test test test)
hg ci -m 'comment'
hg tag
hg push
Then I jump onto the server and do the following when I deploy:
hg update
restart service/webserver as needed
Well, apart from using one of the more capable console editors (Emacs or vi would come to mind), why do you have to edit it on the web server itself? Just edit it remotely if constant FTP/WebDAV transfer would seem to cumbersome.
Emacs has Tramp Mode, gedit on Linux and bbedit on the Mac support remote editing, too. Probably quite a large number of other editors. In that case you would just edit in on a more capable desktop and restart the script from a shell window.
For what it's worth, VIM alone can do the same tasks as previously posted. I have had the same problem with testing Python from the command line.
My solution was to use the screen command. I split screens vertically, I run Python in one instance of a shell, and on the second screen, I usually edit Python code with VIM.
Command to install screen:
sudo apt-get install screen
The screen package has a bit of a learning curve but there isn't any mystery if you can remember the "Ctrl-Alt ?" command that contains all knowledge.
No GUI is required!