Summary:
Buck (our build system) currently starts multiple packager instances for each target and may build multiple targets in parallel. This means we're paying startup costs and are duplicating the work. This enables us to start one instance of the packager and connect to it via socket to do all the work that needs to be done.
The way this is structured:
1. SocketServer: A server that listens on a socket path that is generated based on the server options
2. SocketClient: Interfaces with the server and exposes the operations that we support as methods
3. SocketInterface: Integration point and responsible for forking off the server
Summary:
The transform step in currently the longest one in the bundling process. This adds a progress bar to track the transform progress.
{F23096660}
Summary:
There are two fs steps and it wasn't clear why. This now puts the right label:
```
[9:38:25 PM] <START> Building in-memory fs for JavaScript
[9:38:27 PM] <END> Building in-memory fs for JavaScript (2030ms)
[9:38:27 PM] <START> Building in-memory fs for Assets
[9:38:27 PM] <END> Building in-memory fs for Assets (615ms)
```
Summary:
The `BundlesLayout` will be used as a persistent index. As such, it would be easier to avoid having dependencies to `Module`, `Package`, `Asset`, etc. We're not using that information for now and if we happen to need to use it we could always fetch it using the `ModuleCache`.
Summary:
We've decided to move the syntax for asynchronously requiring async dependencies. The new syntax works better with promises and therefore withe async/await as well. The new syntax looks like this: `System.import('moduleA').then(moduleA => {...});` or if you're using async/await you could simply do:
let moduleA = await System.import('moduleA');
new moduleA().someFunction();
If you need to require multiple dependencies just do:
Promise
.all([System.import('moduleA'), System.import('moduleB')])
.then((moduleA, moduleB) => {...})
or the equivalent using async/await
Summary:
Fix error in the template string (no plus, thinks it's a function).
And bump the timeout to 30 seconds because a file is taking more than 10 seconds `js/RKJSModules/Libraries/FBComponents/FBFed/FeedStoryFragments.js`
Summary:
Since JS doesn't have the guarantee that once a bundle is loaded it will stay in memory (and this is something we actually don't want to enforce to keep memmory usage low), we need to keep track of parent/child relationships on the packager to pass it down to native. As part of this diff, we also introduced an ID for each bundle. The ID for a child bundle is shynthetized as the bundleID of the parent module + an index which gets incremented every time a new bundle is created. For instance given this tree:
a,b
c f
d e g
the ID for `d` will be `bundle.0.1.2`, the one for e will be `bundle.0.1.3` and the one for `g` will be `bundle.0.5.6`. This information will be useful to figure out which bundles need to be loaded when a `require.ensure` is re-written.
Summary:
There's been a case where Babel can hang indefinitely on a file parse/transform. Possibly related to https://github.com/babel/babel/issues/2211
This adds a timeout to transform jobs and throws an error informing the user of the offending file. The timeout interval defaults to 10 seconds, but can be changed via an option.
Summary:
D2319999 introduced a regression where we stopped waiting for the "build haste map" step to finish before we accept any requests. This makes sure that we block on that.
Need to unbreak with this, but will follow up with a test to catch this in the future.
Summary:
Currently the platform selection is controlled by the blacklist. However, since we want to use the same server instance for cross-platform development, we need this to be controlled per request.
One outstanding issue, is that the DependencyGraph class wasn't designed that way and it doesn't have a per-request state. This means that with the current design race conditions is possible. If we got a request for a different platfrom while processing the previous request, we may change the outcome of the previous request.
To fix this a larger refactor is needed. I'll follow up a diff to do that.
Finally, so I don't break the universe like last time, I'll leave it up to the RN guys to update the call sites.
Summary:
This sets NODE_ENV based on the value of the `dev` option when bundling the apps. This would then be inlined by the node-env-inline babel plugin. And finally -- if unreachable -- will be dead-code-eliminated by uglify.
This is not used in development because we set NODE_ENV to the value of __DEV__, which can be switched via a query param. However, the plugin has minimal overhead and to avoid complexity in the transformers I just enabled it by default.
Summary:
Not that at the moment a module can be present in multiple bundles, so the new API will return only one of them. In the near future we'll impose the invariant that a module can only be present in a single bundle so this API will return the exact bundle in which it is.
Summary:
Instead of using plain objects and having to convert to and from them we just use the `Module` class across the codebase.
This seems cleaner and can enforce the type as opposed to fuzzy objects.
Summary:
Introduce a Bundler capable of generating the layout of modules for a given entry point. The current algorithm is the most trivial we could come up with: (1)it puts all the sync dependencies into the same bundle and (2) each group of async dependencies with all their dependencies into a separate bundle. For async dependencies we do this recursivelly, meaning that async dependencies could have async dependencies which will end up on separate bundles as well.
The output of of the layout is an array of bundles. Each bundle is just an array for now with the dependencies in the order the requires where processed. Using this information we should be able to generate the actual bundles by using the `/path/to/entry/point.bundle` endpoint. We might change the structure of this json in the future, for instance to account for parent/child bundles relationships.
The next step will be to improve this algorithm to avoid repeating quite a bit dependencies across bundles.
Summary:
This is the first step to add support for splitting the JS bundle into multiple ones. This diff adds support for keeping track of the async dependencies each module has. To do so we introduce the following syntax:
require.ensure(['dep1', 'dep2, ..., 'depN'], callback);
Where the callback function is asynchronously invoked once all the indicated modules are loaded.
Internally, the packager keeps track of every set of async dependencies a module has. So for instance if a module looks like this:
require.ensure(['dep1'], () => {...});
require.ensure(['dep2'], () => {...});
the `Module` object will keep track of each set of dependencies separately (because we might want to put them on separate bundles).
Summary:
The word Package is overloaded, it may mean npm package, or may mean a collection of bundles. Neither is what we mean. We mean `bundle`.
This renames it and modernize some of the Bundler code.
Summary:
The cache is only used for JSTransformer at the moment. We're doing IO and some computation to get each module's name, whether is a haste or node module and it's dependencies. This work happens on startup so by caching this value we shouldbe able to reduce the start up time. Lets promote the Cache to the Packager level to be able to use it by any of the components of the packager. For now, on this diff we'll start using it to cache the mentioned fields.
Also we had to introduce the concept of fields in the cache as manually merging the date we had for each path is not possible as we're using promisses all around. With the new API, each field is a promise.
@amasad and I did some manual testing to measure the impact of this change and looks like it's saves 1 second when building the haste map (which represents 50% of the time). Overall this reduces 1 second of start up time which was currently about 8s on my mac book pro.
Natansh Verma
Amjad Masad
Martin Konicek
Krzysztof Magiera
Jing Chen
Martín Bigio
Christopher Chedeau
Alex Kotliarskyi
Harrison Harnisch
Tim Yung
Ben Alpert
Felix Oghină
Ludo Fardel
Felix Oghină
Evan Solomon
