Spy
===

Spy is a compact file system watcher for Mac OS X and Linux (Note: Should work
on Windows but is currently untested).


Usage
=====

Spy expects a single argument, the directory or a single file to watch. Spy
currently supports two different modes: watch and run mode.
Press `CTRL-D` to stop watching for file system changes.

Watch mode
-----------

In output mode Spy will print the path to a modified file to STDOUT (followed
by a newline) whenever a file modification (new file added, file modified, file
deleted) occurs.

    $> spy watch .
    path/to/modified/file

Because watch is the default mode you can omit the `watch` command if you want:

    $> spy .

It's possible to watch a single file (this obviously only shows changes to that
particular file):

    $> spy /path/to/file

The default format is the full path to the modified file followed by a newline.
To make it easier to parse the output, the `--format=json` changes the output
to be printed formatted as a JSON object (again followed by a newline).

    $> spy watch --format=json .
    {"path":"/path/to/modified.file","flag":"Added","time":"2012-12-20 11:26:56.859456 UTC"}

Flag is one of "Added", "Modified", "Removed".


For directories the following options apply:

An optional second argument can be used to filter the files in the given
directory using a glob pattern:

    $> spy watch /path/to/directory "*.md"


Run mode
--------

In run mode Spy will execute a given command whenever a file modification
occurs without printing modifications to stdout. The command will be executed
with the path to the modified file as the last argument.

    $> spy run "./run-build.sh"

In the example above the shell script `run-build.sh` would be executed with the
path to the modified file as the first argument.

If the command to be executed does not expect any (additional) arguments the
`--notify-only` flag can be used. This will cause spy to execute the command
without passing the path as an argument:

    $> spy run --notify-only "rake test" .
    
To compile Spy for example use:

    $> spy run -n "cabal build" src


Installation
============

Binary distribution
-------------------

The binary distribution contains a 64bit binary compiled for Mac OS X or Linux.

Download the tarball from https://bitbucket.org/ssaasen/spy/downloads and run "make install" to copy the binary and the man page into the correct target directories:

    $> curl -OL https://bitbucket.org/ssaasen/spy/downloads/spy-PLATFORM-ARCH-VERSION.tar.gz
    $> tar xfz spy-PLATFORM-ARCH-VERSION.tar.gz
    $> cd spy
    $> make install

The user manual should now be available via `man spy` and the `spy` executable should be on your `$PATH`.


Source distribution
-------------------

You need the Haskell platform installed and cabal-install available on your $PATH.

To install spy from hackage simply run:

    $> cabal install spy

Done!

To install spy from git you need the Haskell platform installed and cabal-install available on your $PATH:

    $> git@bitbucket.org:ssaasen/spy.git
    $> cd spy
    $> cabal install --only-dependencies
    $> cabal configure
    $> cabal build

This will create the spy binary in the ./dist/build/spy directory.

To copy the spy binary to the cabal bin directory (which should be available on your PATH) use:

    $> cabal copy