Making FSSM gem (file watcher) do it's thing to all files when it boots

Question

I have a simple FSSM (File System State Monitor) script setup to watch some files and do some things with them when they are changed. It's woking great.

However, I want it to process any files it has an update handler for when I boot my script. As it is now, if I make edits to files before I start the script then my edits arent picked up until I save the file again. And in a project with dozens of files being watched, that is less than ideal.

So how make FSSM process every file it is configured to watch when my script launches?

A snippet of what I have now:

monitor = FSSM::Monitor.new
monitor.path '.' do
  glob '**/*.coffee'

  update do |base, relative|
    coffee base, relative
  end

  delete do |base, relative|
    remove base, relative
  end
end
monitor.run

I'd like it to run the update clause on launch so that any files edited while they were not being watched would get immediately processed.

You could use a log file or sqlite database to store the state of your files being watched (update it each time a file changes and the script is running), check for changes when the script starts via comparing the stored state to the actual. — jvatic, Feb 10 '11 at 17:49

codelahoma · Answer 1 · 2011-04-05T21:19:21.610

The simplest method would probably be to update the timestamp of a zero-byte file on each call of the update clause, then on launch process any files that are newer than that marker file. Since the update clause will need to be used in two places, store it as lambda.

# marker file
ts = ".timestamp"
File.open(ts,"w"){} unless File.exists? ts


# store the update block, so we're DRY
update_clause = lambda do |base, relative| 
       coffee base, relative
       atime = mtime = Time.now
       File.utime(atime, mtime, ts)
end

# run the update against any files newer than the timestamp file
Dir["**/*.coffee"].each do |f|
    if File.mtime(f) > File.mtime(ts)
       update_clause.call(File.dirname(f), File.basename(f))
    end
end

monitor = FSSM::Monitor.new
monitor.path '.' do
  glob '**/*.coffee'

  update &update_clause

  delete do |base, relative|
    remove base, relative
  end
end
monitor.run

I'm fairly new to Ruby, so there may be a cleaner or more idiomatic syntax for this, but the basic idea should take care of you.

Making FSSM gem (file watcher) do it's thing to all files when it boots

1 Answers1