Added File.toJSON method

[Marak]

• Serializes vinyl File object into JSON
• First pass. Seems to be working
• No new tests. Old tests passing.

Hello. Did a quick PR to resolve issue #83

Let me know what you think. I'm still testing this locally, but it seems OK.

Accidentally did two PRs ( missed a project LINT rule ). Sorry.

[yocontra]

LGTM, @phated ?

[phated]

this doesn't seem to handle streaming or null contents

[phated]

Just 1 problem and then I need to run it against gulp-debug

[Marak]

I'm open to suggestion on how to address the null / streaming problem.

[yocontra]

@Marak The same logic from clone can be used in toJSON - clone also handles custom attributes, streaming contents, null stats, etc.

[phated]

I think toJSON is supposed to result in a serializable object

[yocontra]

Yeah idk you can't really serialize a stream synchronously so I guess it'll have to exclude contents if it isn't null or a buffer

[Marak]

Serialization of stream would require entire stream processed into buffer.

So I think maybe method should have option to accept optional callback?

I think in most cases the user would want the actual contents of the file.

[phated]

An optional callback wouldn't work because the toJSON method is called when JSON.stringify is used on the object. Maybe we need to use placeholders (something like <Stream> and <Buffer>)?

[Marak]

Where is JSON.stringify being called? Why would File.toJSON get called via JSON.stringify?

You've lost me. Place holders seem okay, but I'd still need a way to serialize the File instance ( including the streaming file data put into a buffer ).

The goal here is to be able to ship a single File instance over the wire as single buffered JSON message.

[phated]

@Marak Sorry, what I meant is that doing JSON.stringify(new Vinyl()) will call into toJSON

[Marak]

So I think an optional callback would still work?

In the case of JSON.stringify(new Vinyl()), no callback would be provided, which could result in placeholders such as <Stream> or <buffer>?

[Marak]

I'm also wondering, is anyone actually doing JSON.stringify(new Vinyl()) anywhere already? Seems like it wouldn't work right to begin with.

[phated]

I think the best way to handle buffering and serializing would be to use https://www.npmjs.com/package/vinyl-buffer like:

var buffer = require('vinyl-buffer');
var through = require('through2');
vfs.src('**/*.txt', { buffer: false }) // totally contrived
  .pipe(buffer())
  .pipe(through.obj(function(file, enc, cb){
    cb(null, JSON.stringify(file));
  });

I think it makes a lot of sense to just throw on a stream type (or anything non-serializable) which is similar to how JSON.stringify handles circular objects.

[phated]

Currently, calling JSON.stringify on a vinyl object causes the stream object to be serialized, which is terrible!

[Marak]

I see. I'll take a look at bl and vinyl-buffer library a bit.

I've got my fork working here, so I'll continue to push on the use-case I require.

I'll keep a watch on this issue and will post any more code changes I have to make on my fork.

Cheers.

[phated]

After discussions and reading the spec, throwing a TypeError seems wrong/bad. As per @terinjokes, it's looking like nulling contents if it is a stream is the best behavior.

[terinjokes]

Let's make sure to document this, and how a user can convert (and why they shouldn't if necessary)

[Marak]

@phated @terinjokes -

If you null the contents of a stream on serialization, how will you know if the contents were actually null to begin with versus a Stream which got converted to null?

Is that information important to track?

[coveralls]

Coverage decreased (-4.08%) to 95.918% when pulling f5d33ef on Marak:master into 896f68d on gulpjs:master.

[Marak]

More commits will follow. Still working on my integration over here.

[phated]

@Marak cool, really interested to see what behavior you need when you get to streaming contents (if you are using vinyl-fs: vfs.src(glob, { buffer: false })).