yapm/node_modules/fstream/examples/filter-pipe.js

package manager for io.js (npm fork)

var fstream = require("../fstream.js")
var path = require("path")

var r = fstream.Reader({ path: path.dirname(__dirname)
                       , filter: function () {
                           return !this.basename.match(/^\./) &&
                                  !this.basename.match(/^node_modules$/) &&
                                  !this.basename.match(/^deep-copy$/) &&
                                  !this.basename.match(/^filter-copy$/)
                         }
                       })

// this writer will only write directories
var w = fstream.Writer({ path: path.resolve(__dirname, "filter-copy")
                       , type: "Directory"
                       , filter: function () {
                           return this.type === "Directory"
                         }
                       })

var indent = ""
var escape = {}

r.on("entry", appears)
r.on("ready", function () {
  console.error("ready to begin!", r.path)
})

function appears (entry) {
  console.error(indent + "a %s appears!", entry.type, entry.basename, typeof entry.basename)
  if (foggy) {
    console.error("FOGGY!")
    var p = entry
    do {
      console.error(p.depth, p.path, p._paused)
    } while (p = p.parent)

    throw new Error("\033[mshould not have entries while foggy")
  }
  indent += "\t"
  entry.on("data", missile(entry))
  entry.on("end", runaway(entry))
  entry.on("entry", appears)
}

var foggy
function missile (entry) {
  if (entry.type === "Directory") {
    var ended = false
    entry.once("end", function () { ended = true })
    return function (c) {
      // throw in some pathological pause()/resume() behavior
      // just for extra fun.
      process.nextTick(function () {
        if (!foggy && !ended) { // && Math.random() < 0.3) {
          console.error(indent +"%s casts a spell", entry.basename)
          console.error("\na slowing fog comes over the battlefield...\n\033[32m")
          entry.pause()
          entry.once("resume", liftFog)
          foggy = setTimeout(liftFog, 1000)

          function liftFog (who) {
            if (!foggy) return
            if (who) {
              console.error("%s breaks the spell!", who && who.path)
            } else {
              console.error("the spell expires!")
            }
            console.error("\033[mthe fog lifts!\n")
            clearTimeout(foggy)
            foggy = null
            if (entry._paused) entry.resume()
          }

        }
      })
    }
  }

  return function (c) {
    var e = Math.random() < 0.5
    console.error(indent + "%s %s for %d damage!",
                entry.basename,
                e ? "is struck" : "fires a chunk",
                c.length)
  }
}

function runaway (entry) { return function () {
  var e = Math.random() < 0.5
  console.error(indent + "%s %s",
                entry.basename,
                e ? "turns to flee" : "is vanquished!")
  indent = indent.slice(0, -1)
}}


w.on("entry", attacks)
//w.on("ready", function () { attacks(w) })
function attacks (entry) {
  console.error(indent + "%s %s!", entry.basename,
              entry.type === "Directory" ? "calls for backup" : "attacks")
  entry.on("entry", attacks)
}

ended = false
var i = 1
r.on("end", function () {
  if (foggy) clearTimeout(foggy)
  console.error("\033[mIT'S OVER!!")
  console.error("A WINNAR IS YOU!")

  console.log("ok " + (i ++) + " A WINNAR IS YOU")
  ended = true
  // now go through and verify that everything in there is a dir.
  var p = path.resolve(__dirname, "filter-copy")
  var checker = fstream.Reader({ path: p })
  checker.checker = true
  checker.on("child", function (e) {
    var ok = e.type === "Directory"
    console.log((ok ? "" : "not ") + "ok " + (i ++) +
                " should be a dir: " +
                e.path.substr(checker.path.length + 1))
  })
})

process.on("exit", function () {
  console.log((ended ? "" : "not ") + "ok " + (i ++) + " ended")
})

r.pipe(w)