joh/when-changed

Execute a command when a file is changed

when-changed's Issues

Runs the command 3 times every time I save something

If I set it to run a command when a text document is changed, for example, if I save changes to that text document in gedit, when-changed executes the command 3 times. Is this a bug in the way that gedit saves things, or in when-changed?

Doesn't watch files over NFS mount

when-changed isn't working on a NFS mounted directory, after reading through this I suppose watchdog observers are not notifying about the file changes. Just an FYI, if you may add this to notify users on README or help, might help instead of researching.

Documentation: what does the dependency on watchdog mean?

I'm just beginning to investigate this, so I'd never heard of the program 'watchdog' (mentioned in README) before. Google can't help me, because the word is so common.

What am I supposed to install before I try to run this?

pyinotify incompabilities

Since the project uses pyinotify to listen on changes, it is no longer able to do the job in case of Windows OS. Also, It does not work on Linux Guest OS under Windows host in VirtualBox when you are polling files shared with vboxsf module. Codebase is small thus anyone could adjust it a bit to do own job without learning something bigger like http://pythonhosted.org/watchdog/. So far it was very platform-independent. I think kind of fallback would be nice.

Running when-changed on a VirtualBox guest and watching a file in a shared directory, changes made by the host are not detected

Some probably relevant info

$ pip show when-changed

---
Name: when-changed
Version: 0.3.0
Location: /usr/local/lib/python2.7/dist-packages
Requires: watchdog

Both the host and guest OSes are debian Jessie.

Command can't be apply to a directory

Even though When-Changed allows you to monitor directories, it does not allow to run commands over a directory

Mac-Pro-de-Luis:~ luis$ when-changed -[vr1s] "MyDirectory" do shell script "sudo chmod -R 766 " & "/Users/Luis/Documents/Videos Chiapas" password MyPassword with administrator privileges
[6] 1327
-bash: /Users/Luis/Documents/Videos Chiapas: is a directory

include .swo in regexp for excluding vim swap files

Vim's swap files can be more than just .swp and .swx:

• If this file already exists (e.g., when you are recovering from a crash) a
  warning is given and another extension is used, ".swo", ".swn", etc.

On OS X 10.10.5, misses multiple simultaneous file changes

I'm watching a directory of files under OS X 10.10.5, with the latest when-changed and watchdog version 0.8.3. Changing individual files works just fine, but when changing more than one file at a time, only one of the file changes is reported.

I'm happy to give additional details or do tests as requested.

Edit: further info; the changes can be separated by a second or two, and still only the first one is recognized. It looks like all subsequent changes are ignored from when a file is changed until when-changed has finished executing the resulting change command (which in my case takes a few seconds).

Feature request: Add a kill flag

I'd like to kill the currently running command and kick off a fresh one if a file changes. This is in constast with -l which just doesn't execute a second command.

No wheel file in PyPI

Hi there,

I see when-changed got released to PyPI but only as a tarball:
https://pypi.org/project/when-changed/#files

Python wheels are the current standard for packaging pip packages and it will take you seconds to build one.

Could you upload a wheel (.whl) please? All you need to do is python setup.py bdist_wheel and it'll make a .whl file instead of a .tar.gz file. (If you get errors, pip install wheel and try again.)

If you upload directly from commandline then instead of python setup.py sdist upload you do python setup.py sdist bdist_wheel upload. There's not much more to it.

See, when pip installs a package if there is no wheel, it goes and builds one. This involves downloading the tarball, extracting it, generating a wheel internally, copying it to the local pip wheel cache and then deploying it from there. By serving a wheel to begin with, you save a lot of processing as it pretty much just drops in. (This may sound minor but if you're redeploying pip packages frequently, those saved seconds add up!)

You can read more about wheels in the docs:
https://wheel.readthedocs.io/en/stable/user_guide.html#building-wheels

If you're confident your code runs in Python 2 and 3, then you can read more about building a "universal" wheel, which will target both. Else it will be a wheel for the main version that you build with (ie, build in Python 2 and it makes a py2 wheel, build in Python 3 and it makes a py3 wheel.)

Thank you!

Specify dependencies using setuptools

When you pip install when-changed you don't get a working tool, because it doesn't specify that it depends on pyinotify.

Adding a install_requires=['pyinotify'] to setup() (and importing the setup function from setuptools instead of distutils.core) would fix this.

Wildcard support

Hello, can this script support wildcard character like

when-change *.tex -c pdflatex main.tex

My main.tex include multiple sub tex file, how can I make main.tex compile when any tex file in the directory get changed.

Thanks

get the last X lines the added to the file

is it possible to get the changes made to the file as an argument to the command?

Add minimum delay option for accepting new events

Using vim as text editor makes saving (:w) text files trigger two events in a row (almost simultaneously), causing the command to be executed twice. It might be complicated to avoid this, and the file might be actually being written twice, so a suggestion would be to have an option to set a minimum delay to accept a new event after just triggering one.
One example of this is watching .css and .js files then running gulp when one of the files change, but gulp gets executed twice in a row after a single change in one of the files. I tested this in a single text file and it has the same behaviour, two events fired in a row. This happens when using vim, doesn't happen with Sublime Text or nano.

To test this:

touch myfile
# this prints the current system time in milliseconds when myfile is changed
when-changed myfile "echo $(($(date +%s%N)/1000000))"

# in another terminal
vim myfile
[do some change and save it by using :w]
[check the events, you'll see two events triggered in the same millisecond]

An idea is to have a flag to set a minimal delay for accepting a new event. So for example, if the delay is set to 1ms and the above case happens, we got two events being triggered but the second one is ignored because it triggered too fast (before first event + delay).

Again, this happens when saving a file in vim. Doesn't happen in Sublime Text and nano. Other editors have to be tested.

This delay could also useful in many other scenarios, in which you don't want to run the command two times in a row just because the file changed too fast.
Or maybe have support for something like an event queue (and avoid ignoring events triggered) with a minimal delay between each trigger.

-r argument unnecessary?

While trying to figure out what -r does, I found that when-changed behaves recursively, even if you specify a directory without using -r.

As long as this is the case, can we get rid of -r and just make it the default?

WhenChanged.__init__ will automatically pass the recursive argument to watchdog.observers.Observer. However, -r will still matter in WhenChanged.is_interested, which is used by WhenChanged.on_change.

So either the setting is not exactly necessary, or I am misunderstanding its purpose.

Allow wildcards/patterns as FILE argument

Example: when-changed *.tex xelatex %f

Hide any output of given command/s

Hello,

I cannot stop it making prints to stdout or stderr.
Could there be an option for that, please?

Thanks.

On created event not correctly handled on linux

Hi,
the following code taken from the on_created event handler:

if self.observer.__class__.__name__ == 'InotifyObserver':
            # inotify also generates modified events for created files
            return

prevents the on_change method to be called on on_created events.

This appears more as a semantic issue as the on_modified handler seems to do the job for now.
But just partially in fact, because this is the source of the issue #68.
And it would take more importance regarding the issue #58 which implies to distinguish event types.
I think being able to propose an alternative soon.
best regards

Deleted files do not trigger action when watching a directory.

creating of a new file triggers the action, so it makes sense that deleting a file would do that also.

specific file type?

Can I monitor specific file type like "*.py' in a directory?

When you monitor a folder and a file is moved in this folder , it will not trigger

I monitor a folder for new files . These files are not copied there , but moved from other places .

The tool cannot understand these moved files . I tried the -r option , tried to make a second folder inside the folder I monitor , but it doesn't work .
If I copy files it's OK . Problem is that the tools that produce the files are moving them , not copying them.

Runs twice

It runs command twice after my file has changed. In file test.js i have:
console.log('Hello world!');

and after setting when-changed like this:
when-changed test.js node test.js

I get node called twice. Maybe it's worth to mention that I have Python3 as my main Python interpreter.

Command runs twice

Hi!
Thank you for a good work so far!

I have an issue though... I'm running Ubuntu 16.04 and when-changed sometimes executes my command two times when run like so:

when-changed * -c ./pushGit.sh

pushGit.sh:
#!/bin/bash

git commit -am 'save'
git push

Thanks again and have a nice day!

Feature request: Continue watching when parent directory is deleted, or throw error

when-changed has the extremely user friendly behavior of continuing to watch when a file is deleted and replaced. However, this does not hold if the file's directory is deleted or replaced.

If this is not feasible, raising an error would also be helpful.

Upload to pypi

So that I can install when-changed with 'pip install whenchanged' :).

Add tests

Hi,
this refers to this message: #77 (comment)

As some behaviors may differ from a platform to another, it would be great to add a bunch of tests to guarantee that the when-changed behaviors are the expected ones.

The expected behaviors are the following:

When watching directory:

• Existing file is modified
• File is created in the directory
• File is moved into the directory
• File is moved out of the directory
• File is deleted from the directory

When watching a file:

• File is modified
• The file is replaced with another file (overwritten)
• File is renamed
• File is deleted

Unable to install

I am new with this:

I am getting this error:

$ pip install https://github.com/joh/when-changed/archive/maste                                                                                        r.zip
Downloading/unpacking https://github.com/joh/when-changed/archive/master.zip
  Downloading master.zip (unknown size): 4.1kB downloaded
Cleaning up...
Exception:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 290, in                                                                                         run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundl                                                                                        e=self.bundle)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1198, in prepare_file                                                                                        s
    do_download,
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1376, in unpack_url
    self.session,
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 572, in unpack_h                                                                                        ttp_url
    download_hash = _download_url(resp, link, temp_location)
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 433, in _downloa                                                                                        d_url
    for chunk in resp_read(4096):
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 421, in resp_rea                                                                                        d
    chunk_size, decode_content=False):
  File "/usr/lib/python2.7/dist-packages/urllib3/response.py", line 256, in stre                                                                                        am
    data = self.read(amt=amt, decode_content=decode_content)
  File "/usr/lib/python2.7/dist-packages/urllib3/response.py", line 186, in read
    data = self._fp.read(amt)
  File "/usr/lib/python2.7/httplib.py", line 573, in read
    s = self.fp.read(amt)
  File "/usr/lib/python2.7/socket.py", line 380, in read
    data = self._sock.recv(left)
  File "/usr/lib/python2.7/dist-packages/urllib3/contrib/pyopenssl.py", line 188                                                                                        , in recv
    data = self.connection.recv(*args, **kwargs)
ZeroReturnError

Storing debug log for failure in /home/pi/.pip/pip.log

.pip/pip.log
(debug log)

------------------------------------------------------------
/usr/bin/pip run on Sat Jan 16 00:03:28 2016
Downloading/unpacking https://github.com/joh/when-changed/archive/master.zip
  Downloading from URL https://github.com/joh/when-changed/archive/master.zip
Cleaning up...
Exception:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/pip/basecommand.py", line 122, in main
    status = self.run(options, args)
  File "/usr/lib/python2.7/dist-packages/pip/commands/install.py", line 290, in run
    requirement_set.prepare_files(finder, force_root_egg_info=self.bundle, bundle=self.bundle)
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1198, in prepare_files
    do_download,
  File "/usr/lib/python2.7/dist-packages/pip/req.py", line 1376, in unpack_url
    self.session,
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 572, in unpack_http_url
    download_hash = _download_url(resp, link, temp_location)
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 433, in _download_url
    for chunk in resp_read(4096):
  File "/usr/lib/python2.7/dist-packages/pip/download.py", line 421, in resp_read
    chunk_size, decode_content=False):
  File "/usr/lib/python2.7/dist-packages/urllib3/response.py", line 256, in stream
    data = self.read(amt=amt, decode_content=decode_content)
  File "/usr/lib/python2.7/dist-packages/urllib3/response.py", line 186, in read
    data = self._fp.read(amt)
  File "/usr/lib/python2.7/httplib.py", line 573, in read
    s = self.fp.read(amt)
  File "/usr/lib/python2.7/socket.py", line 380, in read
    data = self._sock.recv(left)
  File "/usr/lib/python2.7/dist-packages/urllib3/contrib/pyopenssl.py", line 188, in recv
    data = self.connection.recv(*args, **kwargs)
ZeroReturnError

Force restart without restarting the 'when-changed'

Nodemon [https://github.com/remy/nodemon] has basically the same use case as when-changed, but dedicated for nodejs.
It has this feature that when it monitors a file, one can re-launch the app by typying in 'rs' and hitting return. I believe it is useful when one file depends on others but you don't need to explicitly monitor every each of them. Think of use cases like external config files, temporary changes in libs etc.

I tried my best, but I'm not familiar with Python and from my initial explorations I got this far:

    try:
        wc.run()
    except KeyboardInterrupt:
        print()
        exit(0)
    print('Press a key')
    inkey = _Getch()
    for i in xrange(sys.maxint):
       k=inkey()
       if k=='n':break
    print('you pressed ',k)

But I'm at a loss if this is the right track or if it should work at all. I'd appreciate any hints to complete this.

`watched` set is not modified

Is it intentionally that watched Set initialized at https://github.com/joh/when-changed/blob/master/whenchanged%2Fwhenchanged.py#L100 is then addressed twice to check presence of elements but is never modified?

Triggers twice

...

Use argparse to parse command line arguments

Argparse is a much more cleaner solution to parsing the command line arguments. It will make the code more pythonic 🍔

Ubuntu packaging

Hello,

First off, thanks a lot for your work! This script is super handy for latex. So handy, in fact, I'm considering packaging it for Ubuntu and making it available through a PPA.

Are you (Joh) at all interested in this? I can do the whole thing by myself, but I'm curious if, for example, you'd like to integrate the changes via pull request or if I should just maintain my own fork.

Not working with git log

Thank you so much for this project!

Anything I'm doing wrong?

The same command works with linux's built in watch:

Consider pulling a few commits

Hi. Have a look at my fork -- tremby/when-changed

I don't imagine you'll want to pull everything over (since I see you used to use argparse and then removed it -- I have added optparse which is more widely available but deprecated), but you may be interested in some of them.

Perhaps

• Quiet option
• Notify when command is being run (if not quiet)
• Run command only once per loop even if more than one file has changed
• Clean exit on KeyboardInterrupt

And in the commit which introduced optparse, the command is accepted on stdin rather than as one of the arguments when -c is not used.

Feature request: variable for what just changed

You have %f gets replaced with the file that changed: currently, but ideally I'd like a variable that contains what changed.

File deleted, quotes ignored, and executes in barren environment

I have a couple of issues, and I might try to work on fixes, but they'd be good here for starters.

• File gets deleted = screen full of "No such file or directory" errors
  • Quick solution would be to gracefully exit
  • Better solution would be to print an error and wait
• Quotes are ignored on the command line so you have to escape every one "like this"
  • Maybe use string functions instead of arrays for the command part
• Doesn't execute in your current environment like normal commands would
  • Workaround: use "bash -l"
  • but then you have to use -c to have bash execute the command
  • but then you also have to use -c with when-changed
  • but arguments are still being dropped so you have to also quote the command you're passing to bash
  • but since quotes get ignored normally, you have to also escape your quotes
  • result: when-changed.py file -c bash -l -c "command argument"

Feature request : support for environment variables

Hi,
as many issues #64, #58 refer to some problems that could be addressed partially or completely by environment variables, it should be great to add support for when_changed dedicated environment variables.

Add description of -r flag to the readme

I found it only in the stackoverflow answer

Watching multiple files

It could be nice to have the possibility of watching multiple files at once, either by specifying them as first arguments or by using a wildcard/global/regex syntax

when-changed "file1.cpp file2.cpp" make
when-changed "*.cpp" make
when-changed "file\d+.cpp" make

verbose mode not printing anything

I run when-changed -rv but I don't get any notiofications. What is the verbose mode supposed to print out?

Syntax error on line 27

I'm getting an error when attempting to use when-changed:

Traceback (most recent call last):
  File "/usr/local/bin/when-changed", line 3, in <module>
    from whenchanged.whenchanged import main
  File "/usr/local/lib/python2.6/dist-packages/whenchanged/whenchanged.py", line 27
    self.paths = {os.path.realpath(f): f for f in files}
                                           ^
SyntaxError: invalid syntax

I'm sure it's a simple fix but I don't have much experience with python.

Watch Multiple Directories.

if i'm in a and I have children b and c, and d how do i get this to only watch a/b and a/d?

`**` wildcards are not working inside a `sh` command

Maybe this issue is not related to when-changed, so excuse me if it's the case.

I found that the command when-changed src/**/*.java -c echo %f is working as expected.

But as soon as I use this one sh -c 'when-changed src/**/*.java -c echo %f' I get an error:

OSError: [Errno 2] No such file or directory: '/Users/me/project/src/**'

Unable to run via crontab

This is the command in my crontab

@reboot sh /home/pi/project2/mainfile.sh >> /home/pi/project2/mainfile.log 2>&1

mainfile.sh

#!/bin/sh
when-changed /media/SAIF16GB/shares/ytvideolist.txt -c sh /home/pi/yt-dl/videodl.sh & >> /home/pi/yt-dl/QQQQ.log
when-changed /media/SAIF16GB/shares/ytpllist.txt -c sh /home/pi/yt-dl/playlistdl.sh &

But its not working and log file says that command not found

/home/pi/project2/mainfile.sh: 2: /home/pi/project2/mainfile.sh: when-changed: not found

Syntax error

Hello, I cannot find any examples using this and I'm still getting syntax error. My code is
`
import watchdog
import whenchanged
import subprocess32

when-changed funcaptcha.png print("funcaptcha changed")
`

File is in the same folder as python script. Im using python 2.7

Suggestion : Clean up result to match "watch"

I find it cleaner to run "clear;date;echo;command" instead of command as the 2nd argument to your excellent utility. Perhaps you can make it the default?

[Solved] One hyphen per option

Hi

In case anyone trips over the same issue, I must use a hyphen per each option e.g. when-changed -v -1. Concenating the options doesn't work e.g. `when-changed -v1

How can I get process id of which process changed the file?

Can I get process id of which process changed the file?

Option to specify exclude patterns on the command line

I'd like to use when-changed to run blogofile whenever any of my website sources changes, but unfortunately blogofile writes the output into a subdirectory of the source directory, which triggers when-changed again. Infinite loop.

I'd love to be able to tell when-changed to please ignore changes to website/_site.

New Files

Does this monitor files that are added to the parent directory after the process is launched?