fix(buffer): use safe-buffer polyfill to maintain compatibility

node.js < 4.5 and node.js < 5.9 doesn't support Buffer.alloc and Buffer.from

lib/gridfs-stream/upload.js

@@ -4,6 +4,7 @@ var core = require('mongodb-core');
 var crypto = require('crypto');
 var stream = require('stream');
 var util = require('util');
+var Buffer = require('safe-buffer').Buffer;
 
 var ERROR_NAMESPACE_NOT_FOUND = 26;
 

lib/gridfs/chunk.js

@@ -3,6 +3,8 @@
 var Binary = require('mongodb-core').BSON.Binary,
   ObjectID = require('mongodb-core').BSON.ObjectID;
 
+var Buffer = require('safe-buffer').Buffer;
+
 /**
  * Class for representing a single chunk in GridFS.
  *

lib/gridfs/grid_store.js

@@ -38,7 +38,7 @@
 const Chunk = require('./chunk');
 const ObjectID = require('mongodb-core').BSON.ObjectID;
 const ReadPreference = require('mongodb-core').ReadPreference;
-const Buffer = require('buffer').Buffer;
+const Buffer = require('safe-buffer').Buffer;
 const fs = require('fs');
 const f = require('util').format;
 const util = require('util');

package.json

@@ -13,7 +13,8 @@
     "official"
   ],
   "dependencies": {
-    "mongodb-core": "3.1.2"
+    "mongodb-core": "3.1.2",
+    "safe-buffer": "^5.1.2"
   },
   "devDependencies": {
     "bluebird": "3.5.0",

test/functional/cursor_tests.js

@@ -6,6 +6,7 @@ const expect = require('chai').expect;
 const Long = require('bson').Long;
 const sinon = require('sinon');
 const ReadPreference = require('mongodb-core').ReadPreference;
+const Buffer = require('safe-buffer').Buffer;
 
 describe('Cursor', function() {
   before(function() {

test/functional/cursorstream_tests.js

@@ -1,5 +1,6 @@
 'use strict';
 var expect = require('chai').expect;
+var Buffer = require('safe-buffer').Buffer;
 
 describe('Cursor Streams', function() {
   before(function() {

test/functional/find_tests.js

@@ -3,6 +3,7 @@ const test = require('./shared').assert;
 const setupDatabase = require('./shared').setupDatabase;
 const expect = require('chai').expect;
 const MongoClient = require('../../lib/mongo_client');
+const Buffer = require('safe-buffer').Buffer;
 
 describe('Find', function() {
   before(function() {

test/functional/gridfs_stream_tests.js

@@ -5,7 +5,8 @@ const crypto = require('crypto'),
   fs = require('fs'),
   test = require('./shared').assert,
   setupDatabase = require('./shared').setupDatabase,
-  expect = require('chai').expect;
+  expect = require('chai').expect,
+  Buffer = require('safe-buffer').Buffer;
 
 describe('GridFS Stream', function() {
   before(function() {

test/functional/gridfs_tests.js

@@ -5,7 +5,8 @@ const test = require('./shared').assert,
   fs = require('fs'),
   format = require('util').format,
   child_process = require('child_process'),
-  expect = require('chai').expect;
+  expect = require('chai').expect,
+  Buffer = require('safe-buffer').Buffer;
 
 describe('GridFS', function() {
   before(function() {

test/functional/insert_tests.js

@@ -3,7 +3,8 @@ const test = require('./shared').assert,
   setupDatabase = require('./shared').setupDatabase,
   Script = require('vm'),
   expect = require('chai').expect,
-  normalizedFunctionString = require('bson/lib/bson/parser/utils').normalizedFunctionString;
+  normalizedFunctionString = require('bson/lib/bson/parser/utils').normalizedFunctionString,
+  Buffer = require('safe-buffer').Buffer;
 
 /**
  * Module for parsing an ISO 8601 formatted string into a Date object.

test/functional/operation_example_tests.js

@@ -2,7 +2,8 @@
 const test = require('./shared').assert,
   setupDatabase = require('./shared').setupDatabase,
   f = require('util').format,
-  expect = require('chai').expect;
+  expect = require('chai').expect,
+  Buffer = require('safe-buffer').Buffer;
 
 describe('Operation Examples', function() {
   before(function() {

test/functional/operation_generators_example_tests.js

@@ -1,6 +1,7 @@
 'use strict';
 var test = require('./shared').assert;
 var setupDatabase = require('./shared').setupDatabase;
+var Buffer = require('safe-buffer').Buffer;
 
 /**************************************************************************
  *

test/functional/operation_promises_example_tests.js

@@ -3,6 +3,7 @@ var fs = require('fs');
 var f = require('util').format;
 var test = require('./shared').assert;
 var setupDatabase = require('./shared').setupDatabase;
+var Buffer = require('safe-buffer').Buffer;
 
 var delay = function(ms) {
   return new Promise(function(resolve) {

test/functional/promote_buffers_tests.js

@@ -1,7 +1,7 @@
 'use strict';
 var test = require('./shared').assert;
 var setupDatabase = require('./shared').setupDatabase;
-var Buffer = require('buffer').Buffer;
+var Buffer = require('safe-buffer').Buffer;
 
 describe('Promote Buffers', function() {
   before(function() {