npm start fails with `FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)`

[benkomalo]

Running OS X 10.10.1
The npm install worked fine, but I can't seem to get npm start to work. It fails with a long stream of identical errors:

2015-02-02 10:56 node[24294] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)
2015-02-02 10:56 node[24294] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)
2015-02-02 10:56 node[24294] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)
2015-02-02 10:56 node[24294] (FSEvents.framework) FSEventStreamStart: register_with_server: ERROR: f2d_register_rpc() => (null) (-21)

More info on environment:

$ npm --version
1.3.14

$ node --version
v0.10.22

Seems like it might be a lower level node issue (nodejs/node-v0.x-archive#5463) though a cursory search indicates that there may be workarounds it in the app (e.g. maybe there are ways to reduce the number of files being watched?).

[mfikes]

@benkomalo I can reproduce this if I don't have watchman installed.

[benkomalo]

Ah, interesting. Thanks, @mfikes. If I manually install watchman that gets around that issue (though I'm now seeing Watcher took too long to load, but I can debug that a little more before filing a separate issue for it).

Is there a reason watchman isn't listed in packages.json?

[mfikes]

@benkomalo I had Watcher took too long to load and for me the root cause was a botched pcre installation. See #20

I can't answer the question regarding packages.son (I'm not with Facebook.) The only reason I knew to install it is the recommendation in the main README.md.

[benkomalo]

Cool. Thanks, again @mfikes. I'll assume there's a good reason for keeping it separate from packages.json then. Will close out for now.

[sophiebits]

I don't think we can install watchman automatically via npm.

[mfikes]

I was wondering if this is actually the "node file watching bug" referenced in Step 5 of the Requirements section in README.md. If so, perhaps a future README.md could give a sample line from the endless stream, making it a little easier for devs to know when watchman is needed.

[amasad]

I think we should make it a mandatory dependency. We check for it and exit with a useful error message on how to install it if it's not available. Thoughts?

[mfikes]

My view: While Ben's environment had a few items that are a little older, mine is completely up-to-date (OS X 10.10.2, Node v0.10.36 via brew, and npm version 2.3.0 via brew). So If a lot of users are like me, and if my ability to reproduce this is deterministic (it appears to be), then perhaps watchman should be required instead of recommended.

[amasad]

We can have brew install watchman in the npm postinstall script.

[amasad]

OK, after chatting with @ericvicenti I think the ideal thing to do here is to have a log message with a link to installation directions, because brew is 1) OS X specific and we'll soon have other platforms 2) it feels weird to install native binaries with brew via npm install.