Added limts.js

[mocanew]

Requests are now throttled so that we won't get 429 errors (Too Many Requests) from TMDB.

[impronunciable]

Pretty cool! @rontav I'll take a look during the weekend

[mocanew]

Also, I would recommend that we should use an object instead of multiple arguments for passing settings, but that would require a new dependency to do it easily.

[daviestar]

just to add my 2 cents.. i have an app that uses multiple api's to grab metadata, and have implemented node-rate-limiter to these api's (including this one). if you decide to add this functionality, can there be a way to disable it for users who implement limiting externally?

[daviestar]

Lately my tests have been failing with node-rate-limiter, so this morning I played around with limits.js as I hadn't heard of it before seeing it here. It's a great little utility that seems more fit-for-purpose than node-rate-limiter which is designed primarily for the API owner rather than the API-consumer.

Maybe this kind of thing is more suited to the docs than inside the lib?

Here's a simple wrapper:

const _tmdb = require('moviedb')('your-key')
const limits = require('limits.js')

const throttle = limits().within(1000, 3)

const tmdb = (m, q, cb) => {
  throttle.push(() => _tmdb[m](q, cb))
}

tmdb('searchMovie', {query: 'The Martian', year: 2015}, (err, response) => {
  if(err) return console.error(err)
  console.log(response)
})

Using promises:

const tmdbPromise = (m, q) => new Promise((res, rej) => {
  throttle.push(() => _tmdb[m](q, (err, data) => err ? rej(err) : res(data)))
})

tmdbPromise('searchMovie', {query: 'The Martian', year: 2015})
  .then(console.log)
  .catch(console.error)

[daviestar]

More complex promise example which will only call requestToken once as you spam the function, which allows for more accurate throttling (similar to PR #38):

const _tmdb = require('moviedb')('your-key')
const limits = require('limits.js')

const throttle = limits().within(10 * 1000, 39)

const queue = []
let waitingForToken = false
let haveToken = false

const getToken = () => new Promise((res, rej) => {
  if(haveToken) return res()
  if(waitingForToken) return queue.push(res)

  waitingForToken = true
  _tmdb.requestToken((err) => {
    throttle.push(() => {})
    if(err) return rej(err)
    haveToken = true
    waitingForToken = false
    res()
    queue.map(cb => cb())
    queue.length = 0
  })
})

const tmdb = (m, q) => getToken().then(() => (
  new Promise((res, rej) => {
    throttle.push(() => _tmdb[m](q, (err, data) => err ? rej(err) : res(data)))
  }))
)

tmdb('searchMovie', {query: 'The Martian', year: 2015})
  .then(console.log)
  .catch(console.error)

[impronunciable]

Sorry, I've been busy. I'll try to see this asap

[mocanew]

@daviestar I think that the limiter should be in the lib (and on by default) since it is a limit imposed by TheMovieDB

Also, I don't really understand how the requests sequence works with TMDB. I only implemented what worked for me.

[mocanew]

I would like to change the arguments to an object argument, but that would imply changes to the browser versions too and I don't really understand how those are concatenated.

If @impronunciable would to tell me how he made the current versions, I could make a npm task to automate it (when I will have some free time). (#75)