feat: serialize and de-serialize CID instances

BREAKING CHANGE: return values from de-serializer are now CID instances.
Serializer still supports old link objects.

Author: mikeal

src/resolver.js

@@ -2,6 +2,7 @@
 
 const util = require('./util')
 const traverse = require('traverse')
+const CID = require('cids')
 
 exports = module.exports
 
@@ -80,7 +81,7 @@ function flattenObject (obj, delimiter) {
   }
 
   return traverse(obj).reduce(function (acc, x) {
-    if (typeof x === 'object' && x['/']) {
+    if (CID.isCID(x)) {
       this.update(undefined)
     }
     const path = this.path.join(delimiter)
@@ -125,7 +126,7 @@ exports.isLink = (binaryBlob, path, callback) => {
       return callback(new Error('path out of scope'))
     }
 
-    if (typeof result.value === 'object' && result.value['/']) {
+    if (CID.isCID(result.value)) {
       callback(null, result.value)
     } else {
       callback(null, false)

src/util.js

@@ -15,6 +15,8 @@ const CID_CBOR_TAG = 42
 function tagCID (cid) {
   if (typeof cid === 'string') {
     cid = new CID(cid).buffer
+  } else if (CID.isCID(cid)) {
+    cid = cid.buffer
   }
 
   return new cbor.Tagged(CID_CBOR_TAG, Buffer.concat([
@@ -28,7 +30,7 @@ const decoder = new cbor.Decoder({
     [CID_CBOR_TAG]: (val) => {
       // remove that 0
       val = val.slice(1)
-      return {'/': val}
+      return new CID(val)
     }
   }
 })
@@ -53,9 +55,12 @@ function replaceCIDbyTAG (dagNode) {
       return obj.map(transform)
     }
 
+    if (CID.isCID(obj)) {
+      return tagCID(obj)
+    }
+
     const keys = Object.keys(obj)
 
-    // only `{'/': 'link'}` are valid
     if (keys.length === 1 && keys[0] === '/') {
       // Multiaddr encoding
       // if (typeof link === 'string' && isMultiaddr(link)) {

test/interop.spec.js

@@ -11,9 +11,11 @@ const dagCBOR = require('../src')
 const loadFixture = require('aegir/fixtures')
 const bs58 = require('bs58')
 const isNode = require('detect-node')
+const CID = require('cids')
 
 const arrayLinkCBOR = loadFixture('test/fixtures/array-link.cbor')
 const arrayLinkJSON = require('./fixtures/array-link.json')
+const arrayLink = arrayLinkJSON.map(x => new CID(x['/']))
 
 const emptyArrayCBOR = loadFixture('test/fixtures/empty-array.cbor')
 const emptyArrayJSON = require('./fixtures/empty-array.json')
@@ -41,13 +43,9 @@ describe('dag-cbor interop tests', () => {
       dagCBOR.util.deserialize(arrayLinkCBOR, (err, node) => {
         expect(err).to.not.exist()
         // the JSON version that gets out of go-ipfs stringifies the CID
-        const bs58Str = bs58.encode(node[0]['/'])
+        const bs58Str = node[0].toBaseEncodedString()
 
-        node[0]['/'] = bs58Str
-        expect(node).to.eql(arrayLinkJSON)
-
-        // put it back to bytes
-        node[0]['/'] = bs58.decode(arrayLinkJSON[0]['/'])
+        expect(bs58Str).to.eql(arrayLink[0].toBaseEncodedString())
 
         dagCBOR.util.cid(node, (err, cid) => {
           expect(err).to.not.exist()
@@ -94,7 +92,7 @@ describe('dag-cbor interop tests', () => {
         dagCBOR.util.cid(node, (err, cid) => {
           expect(err).to.not.exist()
           const cidStr = cid.toBaseEncodedString()
-          expect(cidStr).to.eql(expectedCIDs['foo']['/'])
+          expect(cidStr).to.eql(expectedCIDs.foo['/'])
           done()
         })
       })

test/resolver.spec.js

@@ -102,8 +102,7 @@ describe('IPLD format resolver (local)', () => {
     it('resolver.isLink with valid Link', (done) => {
       resolver.isLink(nodeBlob, 'someLink', (err, link) => {
         expect(err).to.not.exist()
-        const linkCID = new CID(link['/'])
-        expect(CID.isCID(linkCID)).to.equal(true)
+        expect(CID.isCID(link)).to.equal(true)
         done()
       })
     })
@@ -157,9 +156,7 @@ describe('IPLD format resolver (local)', () => {
       it('path out of scope', (done) => {
         resolver.resolve(nodeBlob, 'someLink/a/b/c', (err, result) => {
           expect(err).to.not.exist()
-          expect(result.value).to.eql({
-            '/': new CID('QmaNh5d3hFiqJAGjHmvxihSnWDGqYZCn7H2XHpbttYjCNE').buffer
-          })
+          expect(result.value).to.eql(new CID('QmaNh5d3hFiqJAGjHmvxihSnWDGqYZCn7H2XHpbttYjCNE'))
           expect(result.remainderPath).to.equal('a/b/c')
           done()
         })

test/util.spec.js

@@ -9,18 +9,19 @@ const garbage = require('garbage')
 const map = require('async/map')
 const dagCBOR = require('../src')
 const multihash = require('multihashes')
+const CID = require('cids')
 
 describe('util', () => {
   const obj = {
     someKey: 'someValue',
-    link: { '/': Buffer.from('aaaaa') },
+    link: new CID('QmRgutAxd8t7oGkSm4wmeuByG6M51wcTso6cubDdQtuEfL'),
     links: [
-      { '/': Buffer.from('1a') },
-      { '/': Buffer.from('2b') }
+      new CID('QmRgutAxd8t7oGkSm4wmeuByG6M51wcTso6cubDdQtuEfL'),
+      new CID('QmRgutAxd8t7oGkSm4wmeuByG6M51wcTso6cubDdQtuEfL')
     ],
     nested: {
       hello: 'world',
-      link: { '/': Buffer.from('mylink') }
+      link: new CID('QmRgutAxd8t7oGkSm4wmeuByG6M51wcTso6cubDdQtuEfL')
     }
   }