Backwards compatible pure data model API

package.json

@@ -76,6 +76,7 @@
     "aegir": "^22.0.0",
     "chai": "^4.2.0",
     "dirty-chai": "^2.0.1",
+    "chai-subset": "1.6.0",
     "fs-extra": "^9.0.0",
     "ipfs-block-service": "~0.17.0",
     "ipfs-repo": "^3.0.0",
@@ -84,4 +85,4 @@
     "multibase": "^0.7.0",
     "multihashes": "~0.4.19"
   }
-}
+}

src/dag-link/dagLink.js

@@ -15,14 +15,16 @@ class DAGLink {
     //  note - links should include size, but this assert is disabled
     //  for now to maintain consistency with go-ipfs pinset
 
-    this._name = name || ''
-    this._nameBuf = null
-    this._size = size
-    this._cid = new CID(cid)
+    Object.defineProperties(this, {
+      Name: { value: name || '', writable: false, enumerable: true },
+      Tsize: { value: size, writable: false, enumerable: true },
+      Hash: { value: new CID(cid), writable: false, enumerable: true },
+      _nameBuf: { value: null, writable: true, enumerable: false }
+    })
   }
 
   toString () {
-    return `DAGLink <${this._cid.toBaseEncodedString()} - name: "${this.Name}", size: ${this.Tsize}>`
+    return `DAGLink <${this.Hash.toBaseEncodedString()} - name: "${this.Name}", size: ${this.Tsize}>`
   }
 
   toJSON () {
@@ -37,10 +39,6 @@ class DAGLink {
     return Object.assign({}, this._json)
   }
 
-  get Name () {
-    return this._name
-  }
-
   // Memoize the Buffer representation of name
   // We need this to sort the links, otherwise
   // we will reallocate new buffers every time
@@ -49,29 +47,9 @@ class DAGLink {
       return this._nameBuf
     }
 
-    this._nameBuf = Buffer.from(this._name)
+    this._nameBuf = Buffer.from(this.Name)
     return this._nameBuf
   }
-
-  set Name (name) {
-    throw new Error("Can't set property: 'name' is immutable")
-  }
-
-  get Tsize () {
-    return this._size
-  }
-
-  set Tsize (size) {
-    throw new Error("Can't set property: 'size' is immutable")
-  }
-
-  get Hash () {
-    return this._cid
-  }
-
-  set Hash (cid) {
-    throw new Error("Can't set property: 'cid' is immutable")
-  }
 }
 
 exports = module.exports = withIs(DAGLink, { className: 'DAGLink', symbolName: '@ipld/js-ipld-dag-pb/daglink' })

src/dag-node/addLink.js

@@ -26,8 +26,8 @@ const asDAGLink = (link) => {
 
 const addLink = (node, link) => {
   const dagLink = asDAGLink(link)
-  node._links.push(dagLink)
-  node._links = sortLinks(node._links)
+  node.Links.push(dagLink)
+  sortLinks.inplace(node.Links)
 }
 
 module.exports = addLink

src/dag-node/dagNode.js

@@ -25,24 +25,26 @@ class DAGNode {
       throw new Error('Passed \'serializedSize\' must be a number!')
     }
 
-    links = links.map((link) => {
+    links = links.map(link => {
       return DAGLink.isDAGLink(link)
         ? link
         : DAGLink.util.createDagLinkFromB58EncodedHash(link)
     })
-    links = sortLinks(links)
+    sortLinks.inplace(links)
 
-    this._data = data
-    this._links = links
-    this._serializedSize = serializedSize
-    this._size = null
+    Object.defineProperties(this, {
+      Data: { value: data, writable: false, enumerable: true },
+      Links: { value: links, writable: false, enumerable: true },
+      _serializedSize: { value: serializedSize, writable: true, enumerable: false },
+      _size: { value: null, writable: true, enumerable: false }
+    })
   }
 
   toJSON () {
     if (!this._json) {
       this._json = Object.freeze({
         data: this.Data,
-        links: this._links.map((l) => l.toJSON()),
+        links: this.Links.map((l) => l.toJSON()),
         size: this.size
       })
     }
@@ -75,18 +77,15 @@ class DAGNode {
   }
 
   serialize () {
-    return serializeDAGNode({
-      Data: this._data,
-      Links: this._links
-    })
+    return serializeDAGNode(this)
   }
 
   get size () {
     if (this._size === null) {
       if (this._serializedSize === null) {
         this._serializedSize = this.serialize().length
       }
-      this._size = this._links.reduce((sum, l) => sum + l.Tsize, this._serializedSize)
+      this._size = this.Links.reduce((sum, l) => sum + l.Tsize, this._serializedSize)
     }
 
     return this._size
@@ -95,29 +94,6 @@ class DAGNode {
   set size (size) {
     throw new Error("Can't set property: 'size' is immutable")
   }
-
-  // Getters for backwards compatible path resolving
-  get Data () {
-    return this._data
-  }
-
-  set Data (_) {
-    throw new Error("Can't set property: 'Data' is immutable")
-  }
-
-  get Links () {
-    return this._links.map((link) => {
-      return {
-        Name: link.Name,
-        Tsize: link.Tsize,
-        Hash: link.Hash
-      }
-    })
-  }
-
-  set Links (_) {
-    throw new Error("Can't set property: 'Links' is immutable")
-  }
 }
 
 exports = module.exports = withIs(DAGNode, { className: 'DAGNode', symbolName: '@ipld/js-ipld-dag-pb/dagnode' })

src/dag-node/rmLink.js

@@ -4,12 +4,26 @@ const CID = require('cids')
 const { Buffer } = require('buffer')
 
 const rmLink = (dagNode, nameOrCid) => {
+  let predicate = null
+
   // It's a name
   if (typeof nameOrCid === 'string') {
-    dagNode._links = dagNode._links.filter((link) => link.Name !== nameOrCid)
+    predicate = link => link.Name === nameOrCid
   } else if (Buffer.isBuffer(nameOrCid) || CID.isCID(nameOrCid)) {
-    dagNode._links = dagNode._links.filter(
-      (link) => !link.Hash.equals(nameOrCid))
+    predicate = link => link.Hash.equals(nameOrCid)
+  }
+
+  if (predicate) {
+    const links = dagNode.Links
+    let index = 0
+    while (index < links.length) {
+      const link = links[index]
+      if (predicate(link)) {
+        links.splice(index, 1)
+      } else {
+        index++
+      }
+    }
   } else {
     throw new Error('second arg needs to be a name or CID')
   }

src/dag-node/sortLinks.js

@@ -8,12 +8,23 @@ const linkSort = (a, b) => {
 }
 
 /**
- *
+ * Returns new sorted links array.
  * @param {Array} links
  * @returns {Array}
  */
 const sortLinks = (links) => {
   return sort(links, linkSort)
 }
 
+/**
+ * Sorts links in place (mutating given array)
+ * @param {Array} links
+ * @returns {void}
+ */
+const sortLinksInPlace = (links) => {
+  sort.inplace(links, linkSort)
+}
+
+sortLinks.inplace = sortLinksInPlace
+
 module.exports = sortLinks

src/serialize.js

@@ -9,8 +9,8 @@ exports = module.exports
 const toProtoBuf = (node) => {
   const pbn = {}
 
-  if (node.Data && node.Data.length > 0) {
-    pbn.Data = node.Data
+  if (node.Data && node.Data.byteLength > 0) {
+    pbn.Data = asBuffer(node.Data)
   } else {
     // NOTE: this has to be null in order to match go-ipfs serialization
     // `null !== new Buffer(0)`
@@ -20,7 +20,7 @@ const toProtoBuf = (node) => {
   if (node.Links && node.Links.length > 0) {
     pbn.Links = node.Links
       .map((link) => ({
-        Hash: link.Hash.buffer,
+        Hash: asBuffer(link.Hash.buffer),
         Name: link.Name,
         Tsize: link.Tsize
       }))
@@ -31,6 +31,24 @@ const toProtoBuf = (node) => {
   return pbn
 }
 
+/**
+ * Takes bytes in various representations and returns `Buffer`
+ * view of the underyling data without copying.
+ * @param {Buffer|ArrayBuffer|ArrayBufferView} bytes
+ * @returns {Buffer}
+ */
+const asBuffer = (bytes) => {
+  if (Buffer.isBuffer(bytes)) {
+    return bytes
+  } else if (bytes instanceof ArrayBuffer) {
+    return Buffer.from(bytes, 0, bytes.byteLength)
+  } else if (ArrayBuffer.isView(bytes)) {
+    return Buffer.from(bytes.buffer, bytes.byteOffset, bytes.byteLength)
+  } else {
+    return bytes
+  }
+}
+
 /**
  * Serialize internal representation into a binary PB block.
  *

test/dag-link-test.js

@@ -63,7 +63,7 @@ module.exports = (repo) => {
 
     it('has an immutable CID', () => {
       const link = new DAGLink('hello', 3, 'QmXg9Pp2ytZ14xgmQjYEiHjVjMFXzCVVEcRTWJBmLgR39U')
-      expect(() => { link.Hash = 'foo' }).to.throw(/property/)
+      expect(() => { link.Hash = 'foo' }).to.throw(/read.only/)
     })
   })
 }

test/dag-node-test.js

@@ -4,8 +4,10 @@
 const chai = require('chai')
 const { Buffer } = require('buffer')
 const dirtyChai = require('dirty-chai')
+const chaiSubset = require('chai-subset')
 const expect = chai.expect
 chai.use(dirtyChai)
+chai.use(chaiSubset)
 
 const dagPB = require('../src')
 const DAGLink = dagPB.DAGLink
@@ -80,7 +82,7 @@ module.exports = (repo) => {
       })
 
       const node2 = new DAGNode(someData, l2)
-      expect(node2.Links).to.eql([l1[1], l1[0]])
+      expect(node2.Links).to.containSubset([l1[1], l1[0]])
       expect(node1.toJSON()).to.eql(node2.toJSON())
 
       // check sorting