CLI

[Colelyman]

This is a CLI that is heavily based on the CLI from bionode-fasta.

This PR is in response to #8.

I'm not sure if test cases are necessary for a CLI, but I can make them if needed.

[thejmazz]

thanks @Colelyman!

In addition to my comments, I would also suggest switching usage of var to const and let; if we are going to include package-lock.json which is an npm v5 feature, I think it makes sense to use recent syntax as well (at least for new code).

[thejmazz]

include .js extension

[thejmazz]

style: blank line after #!/usr/bin/env node

[Colelyman]

👍 these are fixed, thanks for pointing them out!

[thejmazz]

one line console.log('There was an error:\n', err)

@bmpvieira @tiagofilipe12 do we have an issue for standardized error messages across modules?

[Colelyman]

👍 fixed

[thejmazz]

using .on('data') puts a stream into streams 1 mode - it is preferred to use a pipe instead. It would look something like

const through = require('through2')

fq.pipe(through.obj(function (data, enc, next) {
  this.push(JSON.stringify(data) + '\n')
  next()
  // alternatively, next(null, JSON.stringify(data) + '\n')
})
  .pipe(writeStream)

There is also ndjson.stringify which I believe does the same thing. (and it handles linux vs windows EOL)

So: use ndjson module.

[Colelyman]

@thejmazz I am very new to nodejs streams, so I probably just don't understand the concept behind pipes. But, would using the code that you referenced above require the parser to be refactored? From what I understand, fastq.read(argv._[0]) returns an events.EventEmitter() object, so can an events.EventEmitter() be piped?

Perhaps this is the function of the ndjson module and I just don't know it.

[Colelyman]

From what I can see it looks like the Refactoring branch might be a solution?

[tiagofilipe12]

@thejmazz This is related with the Refactoring branch I made. Check the lib here. I also added checks for if lines are corrupt or malformed but this branch has no CLI and needs to be finished. I think it just needs to export module instead of running it as I did for test purposes (check this line).

[thejmazz]

Ahh yes @Colelyman my bad - I thought this module was a stream. It does not make sense to pipe an event emitter. The CLI from this PR looks like it will work with the changes in refactoring branch - I suggest we merge this in now, finish refactoring (which I think is just some cleaning up and making sure tests pass), and as part of that can implement fs.createReadStream(input).pipe(fastq) in the CLI - which is what it looks like @tiagofilipe12 was using to test refactoring branch.

[tiagofilipe12]

👍

[bmpvieira]

Thanks @Colelyman for the contribution! 🎉 Since this has been reviewed and approved you can go ahead and click the merge button yourself if you want. ;-)

[Colelyman]

Awesome, thanks @bmpvieira!