Files
meteor/tools/fs
Ben Newman 7227f64ea8 Don't assume <10sec build times in watch.isUpToDate.
If you have a lot of packages and you change something in a package that
is used by lots of other packages, such as "meteor" or "modules", then the
rebuild can take a lot longer than ten seconds.
2016-03-14 19:35:52 -04:00
..
2016-02-05 01:46:47 -08:00
2015-08-03 22:09:28 -07:00
2015-08-07 11:18:29 -07:00

This folder contains modules that help communicating with the file-system.

files vs fs and files.path* vs path

Since the Meteor tool was originally written to work on Mac OS X and Linux but now is also required to work on Windows, there has been a decision to abstract the file-system calls to fs and path modules and make them go through the files.js lib.

All path and files manipulations in the tools code assumes it is running in a unixy environment, where the path separator is / and the default line-break symbol is \n; calls like rename and unlink are atomic and the file-system always works as you expect.

The files.js file tries its best to simulate this behavior on Windows, converting slashes, file contents and running FS operations in a "try/sleep/repeat" loop when an EBUSY error is returned. Operations on Windows happen to be slower, especially moving folders and symlinking (which is done by copying the directory instead).

It is advised to use files.readFile and others instead of fs.readFileSync. The methods are Fiberized and are converted on Windows.

Also files.pathJoin instead of path.join and others to properly preserve the unixy feel of paths: /C/Users/IEUser/AppData/Local instead of C:\Users\IEUser\AppData\Local.

mini-files

Some code is shared between the tool libs (this folder) and the code that gets copied to a built bundle (boot.js). The shared code is stored in mini-files.js.

File watching

Since node.js doesn't ship a stable library to watch a folder on all file-systems, a wrapper is used. The wrapper checks if the native functionality works, if not (while on Windows, or a virtualized shared file-system like in VirtualBox), a 5s long-polling is used.

The polling and its numbers are tweakable with the environment variables METEOR_WATCH_POLLING_INTERVAL_MS and METEOR_WATCH_FORCE_POLLING.

Watchset

A specific data-structure that is a set of files and directories paths observed by the file-watcher.