From dfb91373301a5a88b50bcb348207be9853668573 Mon Sep 17 00:00:00 2001
From: Brandon Westcott <brandonwestcott@gmail.com>
Date: Wed, 13 Feb 2019 10:01:51 -0500
Subject: [PATCH] fix: make cbor Decoder configurable (#90)

It's now possible to encode data bigger than the default size.
---
 src/util.js       | 28 ++++++++++++++++++----------
 test/util.spec.js | 21 +++++++++++++++++++++
 2 files changed, 39 insertions(+), 10 deletions(-)

diff --git a/src/util.js b/src/util.js
index 41d611a..9ce1093 100644
--- a/src/util.js
+++ b/src/util.js
@@ -23,16 +23,6 @@ function tagCID (cid) {
   ]))
 }
 
-const decoder = new cbor.Decoder({
-  tags: {
-    [CID_CBOR_TAG]: (val) => {
-      // remove that 0
-      val = val.slice(1)
-      return new CID(val)
-    }
-  }
-})
-
 function replaceCIDbyTAG (dagNode) {
   let circular
   try {
@@ -87,6 +77,24 @@ function replaceCIDbyTAG (dagNode) {
 
 exports = module.exports
 
+let decoder = null
+
+exports.configureDecoder = (opts) => {
+  opts = opts || {}
+  decoder = new cbor.Decoder({
+    tags: Object.assign({
+      [CID_CBOR_TAG]: (val) => {
+        // remove that 0
+        val = val.slice(1)
+        return new CID(val)
+      }
+    }, opts.tags || {}),
+    size: opts.size
+  })
+}
+
+exports.configureDecoder() // Setup default cbor.Decoder
+
 exports.serialize = (dagNode, callback) => {
   let serialized
 
diff --git a/test/util.spec.js b/test/util.spec.js
index ca5823e..e1ad08c 100644
--- a/test/util.spec.js
+++ b/test/util.spec.js
@@ -44,6 +44,27 @@ describe('util', () => {
     })
   })
 
+  it('.serialize and .deserialize large objects', (done) => {
+    const size = 65536 * 2
+    const largeObj = { someKey: [].slice.call(new Uint8Array(size)) }
+    // Configure decoder with custom size
+    dagCBOR.util.configureDecoder({ size: size + 1 })
+
+    dagCBOR.util.serialize(largeObj, (err, serialized) => {
+      expect(err).to.not.exist()
+      expect(Buffer.isBuffer(serialized)).to.equal(true)
+
+      dagCBOR.util.deserialize(serialized, (err, deserialized) => {
+        expect(err).to.not.exist()
+        expect(largeObj).to.eql(deserialized)
+
+        // Reset decoder back to default
+        dagCBOR.util.configureDecoder()
+        done()
+      })
+    })
+  })
+
   it('error catching', (done) => {
     const circlarObj = {}
     circlarObj.a = circlarObj