watchify-ts

watch for browserify builds

Update any source file and your browserify bundle will be recompiled on the spot.

Install

With npm do:

$ npm install --save-dev watchify-ts

Usage

const { watchify } = require("watchify-ts");

watchify is a browserify plugin, so it can be applied like any other plugin. However, when creating the browserify instance b, you MUST set the cache and packageCache properties:

const b = browserify({
  cache: {},
  packageCache: {},
});
b.plugin(watchify);

const b = browserify({
  plugin: [watchify],
  cache: {},
  packageCache: {},
});

By default, watchify doesn't display any output, see events for more info.

b continues to behave like a browserify instance except that it caches file contents and emits an "update" event when a file changes. You should call b.bundle() after the "update" event fires to generate a new bundle. Calling b.bundle() extra times past the first time will be much faster due to caching.

Important: Watchify will not emit "update" events until you've called b.bundle() once and completely drained the stream it returns.

const browserify = require("browserify");
const { createWriteStream } = require("fs");
const { watchify } = require("watchify-ts");

const b = browserify("path/to/entry.js", {
  plugin: [watchify],
  cache: {},
  packageCache: {},
});

const bundle = () => {
  b.bundle().on("error", console.error).pipe(createWriteStream("output.js"));
};

b.on("update", bundle);
bundle();

Options

You can to pass an additional options object as a second parameter of watchify. Its properties are:

opts.delay is the amount of time in milliseconds to wait before emitting an "update" event after a change. Defaults to 100.

opts.ignoreWatch is one or more glob patterns to ignore monitoring files for changes. Defaults to **/node_modules/**.

opts.poll enables polling to monitor for changes. If set to true, then a polling interval of 100ms is used. If set to a number, then that amount of milliseconds will be the polling interval. For more info see Chokidar's documentation on "usePolling" and "interval". This option is useful if you're watching an NFS volume.

const b = browserify({
  cache: {},
  packageCache: {}
});
// watchify defaults:
b.plugin(watchify, {
  delay: 100,
  ignoreWatch: "**/node_modules/**",
  poll: undefined, // Use chokidar default
});

b.close()

Close all the open watch handles.

Events

b.on("update", (ids) => {})

When the bundle changes, emit the array of bundle ids that changed.

b.on("bytes", (bytes) => {})

When a bundle is generated, this event fires with the number of bytes.

b.on("time", (time) => {})

When a bundle is generated, this event fires with the time it took to create the bundle in milliseconds.

b.on("log", (message) => {})

This event fires after a bundle was created with messages of the form:

X bytes written (Y seconds)

with the number of bytes in the bundle X and the time in seconds Y.

Working With Browserify Transforms

If your custom transform for browserify adds new files to the bundle in a non-standard way without requiring. You can inform Watchify about these files by emiting a 'file' event.

module.exports = (file) => {
  return through(function (buf, enc, next) {
    // manipulating file content
    this.emit("file", absolutePathToFileThatHasToBeWatched);
    next();
  });
};

Troubleshooting

Rebuilds on OS X never trigger

It may be related to a bug in fsevents (see #250 and stackoverflow). Try the poll option and/or renaming the project's directory - that might help.

Watchify Swallows Errors

To ensure errors are reported you have to add a event listener to your bundle stream. For more information see (browserify/browserify#1487 (comment) and stackoverflow)

Example:

var b = browserify();
b.bundle().on("error", console.error);

See Also

• budo – a simple development server built on watchify
• errorify – a plugin to add error handling to watchify development
• watchify-request – wraps a watchify instance to avoid stale bundles in HTTP requests
• watchify-middleware – similar to watchify-request, but includes some higher-level features