refactor: move to pull-streams

Author: dignifiedquire

.travis.yml

@@ -2,7 +2,7 @@ sudo: false
 language: node_js
 node_js:
   - 4
-  - 5
+  - stable
 
 # Make sure we have new NPM.
 before_install:

package.json

@@ -2,14 +2,14 @@
   "name": "ipfs-unixfs-engine",
   "version": "0.10.2",
   "description": "JavaScript implementation of the unixfs Engine used by IPFS",
-  "main": "src/index.js",
+  "main": "lib/index.js",
   "jsnext:main": "src/index.js",
   "scripts": {
     "lint": "aegir-lint",
     "build": "aegir-build",
     "test": "aegir-test",
-    "test:node": "aegir-test node",
-    "test:browser": "aegir-test browser",
+    "test:node": "aegir-test --env node",
+    "test:browser": "aegir-test --env browser",
     "release": "aegir-release",
     "release-minor": "aegir-release --type minor",
     "release-major": "aegir-release --type major",
@@ -22,7 +22,7 @@
   ],
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/ipfs/js-ipfs-data-importing.git"
+    "url": "git+https://github.com/ipfs/js-ipfs-unixfs-engine.git"
   },
   "keywords": [
     "IPFS"
@@ -34,37 +34,31 @@
   },
   "homepage": "https://github.com/ipfs/js-ipfs-unixfs-engineg#readme",
   "devDependencies": {
-    "aegir": "^6.0.1",
-    "async": "^2.0.1",
-    "block-stream2": "^1.1.0",
+    "aegir": "^8.0.0",
     "buffer-loader": "0.0.1",
     "chai": "^3.5.0",
-    "concat-stream": "^1.5.1",
-    "fs-blob-store": "^5.2.1",
-    "idb-plus-blob-store": "^1.1.2",
-    "ipfs-repo": "^0.7.5",
+    "fs-pull-blob-store": "^0.3.0",
+    "idb-pull-blob-store": "^0.4.0",
+    "ipfs-block-service": "^0.5.0",
+    "ipfs-repo": "^0.9.0",
     "ncp": "^2.0.0",
-    "pre-commit": "^1.1.2",
+    "pre-commit": "^1.1.3",
+    "pull-zip": "^2.0.0",
     "raw-loader": "^0.5.1",
-    "rimraf": "^2.5.1",
-    "streamifier": "^0.1.1",
-    "ipfs-block-service": "^0.3.0",
-    "string-to-stream": "^1.0.1"
+    "rimraf": "^2.5.4",
+    "run-series": "^1.1.4"
   },
   "dependencies": {
-    "block-stream2": "^1.1.0",
-    "bs58": "^3.0.0",
-    "debug": "^2.2.0",
-    "field-trip": "0.0.3",
-    "ipfs-merkle-dag": "^0.6.1",
-    "ipfs-unixfs": "^0.1.0",
+    "ipfs-merkle-dag": "^0.7.0",
+    "ipfs-unixfs": "^0.1.4",
     "is-ipfs": "^0.2.0",
-    "isstream": "^0.1.2",
     "multihashes": "^0.2.2",
-    "readable-stream": "^1.1.13",
-    "run-series": "^1.1.4",
-    "streamifier": "^0.1.1",
-    "through2": "^2.0.0"
+    "pull-block": "^1.0.2",
+    "pull-pushable": "^2.0.1",
+    "pull-stream": "^3.4.5",
+    "pull-traverse": "^1.0.3",
+    "pull-write": "^1.1.0",
+    "run-parallel": "^1.1.6"
   },
   "contributors": [
     "David Dias <[email protected]>",
@@ -75,4 +69,4 @@
     "greenkeeperio-bot <[email protected]>",
     "nginnever <[email protected]>"
   ]
-}
+}

src/chunker-fixed-size.js

@@ -1,7 +1,7 @@
 'use strict'
 
-const chunker = require('block-stream2')
+const block = require('pull-block')
 
 exports = module.exports = function (size) {
-  return chunker({ size: size, zeroPadding: false })
+  return block(size, {zeroPadding: false})
 }

src/clean-multihash.js

@@ -1,124 +1,40 @@
 'use strict'
 
-const debug = require('debug')
-const log = debug('unixfs')
-log.err = debug('unixfs:error')
 const isIPFS = require('is-ipfs')
-const UnixFS = require('ipfs-unixfs')
-const series = require('run-series')
-const Readable = require('readable-stream').Readable
-const pathj = require('path')
-const util = require('util')
-const fieldtrip = require('field-trip')
-const cleanMultihash = require('./clean-multihash')
+const traverse = require('pull-traverse')
+const pull = require('pull-stream')
 
-exports = module.exports = Exporter
+const util = require('./util')
+const switchType = util.switchType
+const cleanMultihash = util.cleanMultihash
 
-util.inherits(Exporter, Readable)
+const dirExporter = require('./exporters/dir')
+const fileExporter = require('./exporters/file')
 
-function Exporter (hash, dagService, options) {
-  if (!(this instanceof Exporter)) {
-    return new Exporter(hash, dagService, options)
-  }
-
-  // Sanitize hash
-  if (!isIPFS.multihash(hash)) {
-    throw new Error('not valid multihash')
-  }
+module.exports = (hash, dagService, options) => {
   hash = cleanMultihash(hash)
-
-  Readable.call(this, { objectMode: true })
-
-  this.options = options || {}
-
-  this._read = (n) => {}
-
-  let fileExporter = (node, name, done) => {
-    if (!done) {
-      throw new Error('done must be set')
-    }
-
-    const contentRS = new Readable()
-    contentRS._read = () => {}
-
-    // Logic to export a single (possibly chunked) unixfs file.
-    if (node.links.length === 0) {
-      const unmarshaledData = UnixFS.unmarshal(node.data)
-      contentRS.push(unmarshaledData.data)
-      contentRS.push(null)
-      this.push({ content: contentRS, path: name })
-      done()
-    } else {
-      const array = node.links.map((link) => {
-        return (cb) => {
-          dagService.get(link.hash, (err, res) => {
-            if (err) {
-              return cb(err)
-            }
-            var unmarshaledData = UnixFS.unmarshal(res.data)
-            contentRS.push(unmarshaledData.data)
-            cb()
-          })
-        }
-      })
-      series(array, (err) => {
-        if (err) {
-          return contentRS.emit('error', err)
-        }
-        contentRS.push(null)
-      })
-      this.push({ content: contentRS, path: name })
-      done()
-    }
-  }
-
-  // Logic to export a unixfs directory.
-  let dirExporter = (node, name, add, done) => {
-    if (!add) {
-      throw new Error('add must be set')
-    }
-    if (!done) {
-      throw new Error('done must be set')
-    }
-
-    this.push({content: null, path: name})
-
-    // Directory has links
-    if (node.links.length > 0) {
-      node.links.forEach((link) => {
-        add({ path: pathj.join(name, link.name), hash: link.hash })
-      })
-    }
-    done()
-  }
-
-  // Traverse the DAG asynchronously
-  fieldtrip([{path: hash, hash: hash}], visit.bind(this), (err) => {
-    if (err) {
-      return this.emit('error', err)
-    }
-    this.push(null)
-  })
-
-  // Visit function: called once per node in the exported graph
-  function visit (item, add, done) {
-    dagService.get(item.hash, (err, node) => {
-      if (err) {
-        return this.emit('error', err)
-      }
-
-      const data = UnixFS.unmarshal(node.data)
-      const type = data.type
-
-      if (type === 'directory') {
-        dirExporter(node, item.path, add, done)
-      }
-
-      if (type === 'file') {
-        fileExporter(node, item.path, done)
-      }
-    })
+  options = options || {}
+
+  function visitor (item) {
+    return pull(
+      dagService.getStream(item.hash),
+      pull.map((node) => switchType(
+        node,
+        () => dirExporter(node, item.path, dagService),
+        () => fileExporter(node, item.path, dagService)
+      )),
+      pull.flatten()
+    )
   }
 
-  return this
+  // Traverse the DAG
+  return pull(
+    dagService.getStream(hash),
+    pull.map((node) => switchType(
+      node,
+      () => traverse.widthFirst({path: hash, hash}, visitor),
+      () => fileExporter(node, hash, dagService)
+    )),
+    pull.flatten()
+  )
 }

src/exporter.js

@@ -0,0 +1,28 @@
+'use strict'
+
+const path = require('path')
+const pull = require('pull-stream')
+
+const fileExporter = require('./file')
+const switchType = require('../util').switchType
+
+// Logic to export a unixfs directory.
+module.exports = (node, name, dagService) => {
+  return pull(
+    pull.values(node.links),
+    pull.map((link) => ({
+      path: path.join(name, link.name),
+      hash: link.hash
+    })),
+    pull.map((item) => pull(
+      dagService.getStream(item.hash),
+      pull.map((n) => switchType(
+        n,
+        () => pull.values([item]),
+        () => fileExporter(n, item.path, dagService)
+      )),
+      pull.flatten()
+    )),
+    pull.flatten()
+  )
+}

src/exporters/dir.js

@@ -0,0 +1,31 @@
+'use strict'
+
+const UnixFS = require('ipfs-unixfs')
+const pull = require('pull-stream')
+
+function extractContent (node) {
+  const raw = UnixFS.unmarshal(node.data)
+  return pull.values([raw.data])
+}
+
+// Logic to export a single (possibly chunked) unixfs file.
+module.exports = (node, name, ds) => {
+  let content
+
+  if (node.links.length === 0) {
+    content = extractContent(node)
+  } else {
+    content = pull(
+      pull.values(node.links),
+      pull.map((link) => ds.getStream(link.hash)),
+      pull.flatten(),
+      pull.map(extractContent),
+      pull.flatten()
+    )
+  }
+
+  return pull.values([{
+    content: content,
+    path: name
+  }])
+}