run a single javascript file

[dominictarr]

How do I run a single javascript file? with browserify it's really easy to take a lot of javascript and run it on any javascript platform, however nucleus seems to insist on running directories that is constraining as often I just want to run, say, a test script.

I did get this to work, https://github.com/dominictarr/nucleus-run

and I understand that it is ment to be possible to create a new nucleus command by just appending a zip of the code? I tried this but was not able to find any documentation.

zip n ../nucleus-run/
cat ./target/debug/nucleus n.zip > nr

but that didn't seem to work.

bundling the zip file is a pretty great idea, but a single js file is still the lowest common denomenator of javascript, so it seems reasonable that works out of the box.

[Fishrock123]

@dominictarr does -N --no-bundle work for what you want? (for single files or "node like")

It does not currently work with zips though.

I had this same problem with the original version of nucleus which is pretty much why I've added this.

See also nucleus-js/design#22 -- @creationix seems to think people will get confused and have problems with programs that were accessing files during testing but can't when zipped up. Not sure I agree though.

and I understand that it is ment to be possible to create a new nucleus command by just appending a zip of the code? I tried this but was not able to find any documentation.

Right, if you append a zip that has a main.js in it, it will execute starting with that file from within the zip.

This is documented in my PR for CLI options to the spec in https://github.com/nucleus-js/design/pull/30/files#diff-7becf02ad489c02e98feeccea97f1ad4R7, but should also be stated elsewhere.

(It should also be configurable ala #8)

[Fishrock123]

(the fact that both you and I have had to ask this question means it is definitely a problem lol)

[dominictarr]

oh, thanks!
-N, --no-bundle do not execute as a bundle
did not sound like what i was looking for
-f FILE execute a single file
would have been more obvious.

[Fishrock123]

Makes sense, we can totally change it to that!

[dominictarr]

hmm, okay so I recalled that zip files have an index at the end, and for that reason I thought maybe you could just append the zip. If you have to frame the zip, could you also have a framing that just appends a single file? also, would it be possible to have multiple files or zips that each bootstrap a layer?

[Fishrock123]

hmm, okay so I recalled that zip files have an index at the end, and for that reason I thought maybe you could just append the zip. If you have to frame the zip, could you also have a framing that just appends a single file?

If what you are asking is like this example from the design repo, then that would be correct:

# Manually build a standalone binary with nucleus embedded.
cat /usr/local/bin/nucleus app.zip > app
chmod +x app
./app args...

also, would it be possible to have multiple files or zips that each bootstrap a layer?

I have literally no idea, maybe @creationix knows

[dominictarr]

I remembered @creationix describing how luvit worked, and structure of zip files make this easy:
https://en.wikipedia.org/wiki/Zip_(file_format)#Structure

It seems like a neat idea, but I can just imagine needing to have multiple layers of bootstrapping.

hmm, I guess you can jump to the directory, and that tells you the length of the file, and then you can just work backwards. you could apply this same idea to a file, by just appending a length as the last line..

cat $(which nucleus) app.js $(stat -c %s log.js)  > nukeapp

okay that might need a empty line at the end of app.js
but then you could read back, and then execute forward, and nukeapp could even be extended this way, it would be composable.

[creationix]

There is no explicit framing in the design outside of the zip format itself.

Is it really that hard to make a zip file containing a single file? The nucleus CLI tool should make the zip for you even. I guess we just need a mode where you pass it a file instead of a directory and it creates a zip containing only that file as main.js. I would think that would work well as long as your single file doesn't expect ant other files to be present in the bundle.

[dominictarr]

@creationix sure that would work!