howdoi

instant coding answers via the command line

Are you a hack programmer? Do you find yourself constantly Googling for how to do basic programming tasks?

Suppose you want to know how to format a date in bash. Why open your browser and read through blogs (risking major distraction) when you can simply stay in the console and ask howdoi:

$ howdoi format date bash
> DATE=`date +%Y-%m-%d`

howdoi will answer all sorts of queries:

$ howdoi print stack trace python
> import traceback
>
> try:
>     1/0
> except:
>     print '>>> traceback <<<'
>     traceback.print_exc()
>     print '>>> end of traceback <<<'
> traceback.print_exc()

$ howdoi convert mp4 to animated gif
> video=/path/to/video.avi
> outdir=/path/to/output.gif
> mplayer "$video" \
>         -ao null \
>         -ss "00:01:00" \  # starting point
>         -endpos 10 \ # duration in second
>         -vo gif89a:fps=13:output=$outdir \
>         -vf scale=240:180

$ howdoi create tar archive
> tar -cf backup.tar --exclude "www/subf3" www

Installation

pip install howdoi

or

pip install git+https://github.com/gleitz/howdoi.git#egg=howdoi

or

python setup.py install

Usage

usage: howdoi.py [-h] [-p POS] [-a] [-l] [-c] [-n NUM_ANSWERS] [-C] [-v] [-e ENGINE] QUERY [QUERY ...]

instant coding answers via the command line

positional arguments:
  QUERY                 the question to answer

optional arguments:
  -h, --help            show this help message and exit
  -p POS, --pos POS     select answer in specified position (default: 1)
  -a, --all             display the full text of the answer
  -l, --link            display only the answer link
  -c, --color           enable colorized output
  -n NUM_ANSWERS, --num-answers NUM_ANSWERS
                        number of answers to return
  -C, --clear-cache     clear the cache
  -v, --version         displays the current version of howdoi
  -e ENGINE, --engine ENGINE  change search engine for this query only. Currently supported engines: google (default), bing, duckduckgo.

As a shortcut, if you commonly use the same parameters each time and don't want to type them, add something similar to your .bash_profile (or otherwise). This example gives you 5 colored results each time.

alias h='function hdi(){ howdoi $* -c -n 5; }; hdi'

And then to run it from the command line simply type:

$h this is my query for howdoi

Author

• Benjamin Gleitzman (@gleitz)

Notes

• Works with Python2 and Python3
• A GUI that wraps howdoi is available here.
• A Flask webapp that wraps howdoi is available here.
• An Alfred Workflow for howdoi can be found at http://blog.gleitzman.com/post/48539944559/howdoi-alfred-even-more-instant-answers.
• Slack integration available through slack-howdoi.
• Howdoi uses a cache for faster access to previous questions. Caching functionality can be disabled by setting the HOWDOI_DISABLE_CACHE environment variable. The cache is stored in ~/.cache/howdoi.
• You can set the HOWDOI_URL environment variable to change the source url for answers (default: stackoverflow.com, also supported: serverfault.com, pt.stackoverflow.com, full list).
• You can set the HOWDOI_SEARCH_ENGINE environment variable to change the underlying search engine for StackOverflow links (default: google, also supported: bing, duckduckgo). The -e flag will switch the underlying engine for a single query.
• Setting the HOWDOI_COLORIZE environment variable will colorize the output by default.
• Special thanks to Rich Jones (@miserlou) for the idea.

Development

• Checkout the repo
• Run python -m howdoi.howdoi QUERY (if you try running python howdoi/howdoi.py you might get ValueError: Attempted relative import in non-package).

If you would like to use howdoi from within a python script, use the following snippet:

from howdoi import howdoi

query = "for loop python"
parser = howdoi.get_parser()
args = vars(parser.parse_args(query.split(' ')))

output = howdoi.howdoi(args)

Contributing

I'm happy to accept pull requests that make howdoi better. If you're thinking of contributing and want a little feedback before you jump into the codebase, post an issue on Github.

Before PRs are accepted they must pass all Travis tests and not have any flake8 or pylint warnings or errors. This projects uses vanilla configuration files for both linters (.flake8rc and .pylintrc in the root directory), but with a max line length of 119.

Troubleshooting

You might get the following error when installing with Homebrew:

==> python setup.py install

http://peak.telecommunity.com/EasyInstall.html

Please make the appropriate changes for your system and try again.

Fix the error by executing the following command:

sudo chmod -R go+w /Library/Python/2.7/site-packages/

An official lxml for python 3.3+ for windows has not yet been released. You may get an error while installing. Try and install an unofficial binary for lxml from

http://www.lfd.uci.edu/~gohlke/pythonlibs/#lxml