added checks for correct multihash key

package.json

@@ -23,8 +23,8 @@
     "url": "https://github.com/vijayee/js-ipfs-merkle-dag.git"
   },
   "dependencies": {
-    "bl": "^1.0.0",
     "ipfs-blocks": "^0.1.0",
+    "is-ipfs": "^0.1.0",
     "multihashing": "^0.2.0",
     "protocol-buffers": "^3.1.4",
     "stable": "^0.1.5"

src/dag-service.js

@@ -1,5 +1,7 @@
-var DAGNode = require('./dag-node').DAGNode
-var Block = require('ipfs-blocks').Block
+const DAGNode = require('./dag-node').DAGNode
+const Block = require('ipfs-blocks').Block
+const isIPFS = require('is-ipfs')
+const base58 = require('bs58')
 
 exports = module.exports = DAGService
 
@@ -23,10 +25,30 @@ function DAGService (blockService) {
   // this.addRecursive
 
   // get retrieves a DAGNode, using the Block Service
-  this.get = (multihash, callback) => {
-    if (!multihash) { return callback(new Error('Invalid Key')) }
+  this.get = function (multihash, callback) {
+    if (Buffer.isBuffer(multihash)) {
+      var mhString = base58.encode(multihash)
+      if (!isIPFS.multihash(mhString)) { return callback(new Error('Invalid Key')) }
+      this.getWith(multihash, callback)
+    }
+
+    if (typeof multihash === 'string') {
+      if (!isIPFS.multihash(multihash) && !isIPFS.path(multihash)) {
+        return callback(new Error('Invalid Key'))
+      }
+      if (isIPFS.multihash(multihash)) {
+        var mhBuffer = new Buffer(base58.decode(multihash))
+        this.getWith(mhBuffer, callback)
+      }
+      if (isIPFS.path(multihash)) {
+        var ipfsKey = new Buffer(base58.decode(multihash.replace('/ipfs/', '')))
+        this.getWith(ipfsKey, callback)
+      }
+    }
+  }
 
-    this.bs.getBlock(multihash, (err, block) => {
+  this.getWith = function (key, callback) {
+    this.bs.getBlock(key, (err, block) => {
       if (err) { return callback(err) }
       var node = new DAGNode()
       node.unMarshal(block.data)

tests/merkle-dag-tests.js

@@ -154,7 +154,22 @@ module.exports = function (repo) {
       })
     })
 
-    it('get a mdag node', (done) => {
+    it('get a mdag node from base58 encoded string', (done) => {
+      const node = new DAGNode(new Buffer('more data data data'))
+      dagService.add(node, (err) => {
+        expect(err).to.not.exist
+        var mh = node.multihash()
+        var encodedMh = bs58.encode(mh)
+        dagService.get(encodedMh, (err, fetchedNode) => {
+          expect(err).to.not.exist
+          expect(node.data).to.deep.equal(fetchedNode.data)
+          expect(node.links).to.deep.equal(fetchedNode.links)
+          done()
+        })
+      })
+    })
+
+    it('get a mdag node from a multihash buffer', (done) => {
       const node = new DAGNode(new Buffer('more data data data'))
       dagService.add(node, (err) => {
         expect(err).to.not.exist
@@ -168,6 +183,41 @@ module.exports = function (repo) {
       })
     })
 
+    it('get a mdag node from a /ipfs/ path', (done) => {
+      const node = new DAGNode(new Buffer('more data data data'))
+      dagService.add(node, (err) => {
+        expect(err).to.not.exist
+        var mh = node.multihash()
+        var encodedMh = bs58.encode(mh)
+        var ipfsPath = '/ipfs/' + encodedMh
+        dagService.get(ipfsPath, (err, fetchedNode) => {
+          expect(err).to.not.exist
+          expect(node.data).to.deep.equal(fetchedNode.data)
+          expect(node.links).to.deep.equal(fetchedNode.links)
+          done()
+        })
+      })
+    })
+
+    it('supply an improperly formatted string path', (done) => {
+      var mh = 'bad path'
+      var ipfsPath = '/ipfs/' + mh
+      dagService.get(ipfsPath, (err, fetchedNode) => {
+        var error = 'Error: Invalid Key'
+        expect(err.toString()).to.eql(error)
+        done()
+      })
+    })
+
+    it('supply improperly formatted multihash buffer', (done) => {
+      var mh = new Buffer('more data data data')
+      dagService.get(mh, (err, fetchedNode) => {
+        var error = 'Error: Invalid Key'
+        expect(err.toString()).to.eql(error)
+        done()
+      })
+    })
+
     it('get a dag recursively', (done) => {
       // 1 -> 2 -> 3
       const node1 = new DAGNode(new Buffer('1'))