Export Python interpreter history to a file?

If you are using Linux/Mac and have readline library, you could add the following to a file and export it in your .bash_profile and you will have both completion and history.

# python startup file
import readline
import rlcompleter
import atexit
import os
# tab completion
readline.parse_and_bind('tab: complete')
# history file
histfile = os.path.join(os.environ['HOME'], '.pythonhistory')
try:
    readline.read_history_file(histfile)
except IOError:
    pass
atexit.register(readline.write_history_file, histfile)
del os, histfile, readline, rlcompleter

Export command:

export PYTHONSTARTUP=path/to/.pythonstartup

This will save your python console history at ~/.pythonhistory


IPython is extremely useful if you like using interactive sessions. For example for your usecase there is the save command, you just input save my_useful_session 10-20 23 to save input lines 10 to 20 and 23 to my_useful_session.py. (to help with this, every line is prefixed by its number)

Look at the videos on the documentation page to get a quick overview of the features.

::OR::

There is a way to do it. Store the file in ~/.pystartup

# Add auto-completion and a stored history file of commands to your Python
# interactive interpreter. Requires Python 2.0+, readline. Autocomplete is
# bound to the Esc key by default (you can change it - see readline docs).
#
# Store the file in ~/.pystartup, and set an environment variable to point
# to it:  "export PYTHONSTARTUP=/home/user/.pystartup" in bash.
#
# Note that PYTHONSTARTUP does *not* expand "~", so you have to put in the
# full path to your home directory.

import atexit
import os
import readline
import rlcompleter

historyPath = os.path.expanduser("~/.pyhistory")

def save_history(historyPath=historyPath):
    import readline
    readline.write_history_file(historyPath)

if os.path.exists(historyPath):
    readline.read_history_file(historyPath)

atexit.register(save_history)
del os, atexit, readline, rlcompleter, save_history, historyPath

You can also add this to get autocomplete for free:

readline.parse_and_bind('tab: complete')

Please note that this will only work on *nix systems. As readline is only available in Unix platform.


Much has changed over the last 8 years since this question was asked.

It appears that since Python 3.4, history is automatically written to ~/.python_history as a plain text file.

If you want to disable that or learn more, check out

  • How can I disable the new history feature in Python 3.4? - Unix & Linux Stack Exchange
  • Readline configuration - Site-specific configuration hook — Python 3.7.2 documentation

And, of course, as noted by many others, IPython has great features for saving, searching and manipulating history. Learn more via %history?


The following is not my own work, but frankly I don't remember where I first got it... However: place the following file (on a GNU/Linux system) in your home folder (the name of the file should be .pystartup.py):

# Add auto-completion and a stored history file of commands to your Python
# interactive interpreter. Requires Python 2.0+, readline. Autocomplete is
# bound to the Esc key by default (you can change it - see readline docs).
#
# Store the file in ~/.pystartup, and set an environment variable to point
# to it, e.g. "export PYTHONSTARTUP=/max/home/itamar/.pystartup" in bash.
#
# Note that PYTHONSTARTUP does *not* expand "~", so you have to put in the
# full path to your home directory.

import atexit
import os
import readline
import rlcompleter

historyPath = os.path.expanduser("~/.pyhistory")
historyTmp = os.path.expanduser("~/.pyhisttmp.py")

endMarkerStr= "# # # histDUMP # # #"

saveMacro= "import readline; readline.write_history_file('"+historyTmp+"'); \
    print '####>>>>>>>>>>'; print ''.join(filter(lambda lineP: \
    not lineP.strip().endswith('"+endMarkerStr+"'),  \
    open('"+historyTmp+"').readlines())[-50:])+'####<<<<<<<<<<'"+endMarkerStr

readline.parse_and_bind('tab: complete')
readline.parse_and_bind('\C-w: "'+saveMacro+'"')

def save_history(historyPath=historyPath, endMarkerStr=endMarkerStr):
    import readline
    readline.write_history_file(historyPath)
    # Now filter out those line containing the saveMacro
    lines= filter(lambda lineP, endMarkerStr=endMarkerStr:
                      not lineP.strip().endswith(endMarkerStr), open(historyPath).readlines())
    open(historyPath, 'w+').write(''.join(lines))

if os.path.exists(historyPath):
    readline.read_history_file(historyPath)

atexit.register(save_history)

del os, atexit, readline, rlcompleter, save_history, historyPath
del historyTmp, endMarkerStr, saveMacro

You will then get all the goodies that come with bash shell (up and down arrows navigating the history, ctrl-r for reverse search, etc....).

Your complete command history will be stored in a file located at: ~/.pyhistory.

I'm using this from ages and I never got a problem.

HTH!

Tags:

Python

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