BetterFileWatching.jl

watch_folder(f::Function, dir=".")

Watch a folder recursively for any changes. Includes changes to file contents. A FileEvent is passed to the callback function f.

watch_file(f::Function, filename=".")

Watch a file for changes. A FileEvent is passed to the callback function f.

FileEvent

The object passed to the callback function f is a FileEvent. This is a supertype, with the following subtypes:

julia> BetterFileWatching.FileEvent |> subtypes
7-element Vector{Any}:
 BetterFileWatching.Accessed
 BetterFileWatching.AnyEvent
 BetterFileWatching.Created
 BetterFileWatching.Modified
 BetterFileWatching.Other
 BetterFileWatching.Removed
 BetterFileWatching.Renamed

Each of these types as a .paths field, which is a vector of strings. This is the path of the file or folder that changed. In practice, the AnyEvent and Other occur only rarely, as a fallback when the specific event type is not known.

Example

watch_folder(".") do event
    @info "Something changed!" event
end

You can watch a folder asynchronously, and interrupt the task later:

watch_task = @async watch_folder(".") do event
    @info "Something changed!" event
end

sleep(5)

# stop watching the folder
schedule(watch_task, InterruptException(); error=true)

Differences with the FileWatching stdlib

BetterFileWatching.watch_file is an alternative to FileWatching.watch_file. The differences are:

• We offer an additional callback API (watch_file(::Function, ::String), like the examples above), which means that handling events does not block receiving new events: we keep listening to changes asynchronously while your callback runs.
• BetterFileWatching.jl is just a small wrapper around Deno.watchFs, made available through the Deno_jll package. Deno.watchFs is well-tested and widely used.

BetterFileWatching.watch_folder is an alternative to FileWatching.watch_folder. The differences are, in addition to those mentioned above for watch_file:

• BetterFileWatching.watch_folder works recursively, i.e. subfolders are also watched.
• BetterFileWatching.watch_folder also watches for changes to the contents of files contained in the folder.

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In fact, BetterFileWatching.watch_file and BetterFileWatching.watch_folder are actually just the same function! It handles both files and folders.