support node buffers less than 8192 bytes (#773)

lib/adapters/http.js

@@ -30,13 +30,15 @@ module.exports = function httpAdapter(config) {
     }
 
     if (data && !utils.isStream(data)) {
-      if (utils.isArrayBuffer(data)) {
+      if (utils.isBuffer(data)) {
+        // Nothing to do...
+      } else if (utils.isArrayBuffer(data)) {
         data = new Buffer(new Uint8Array(data));
       } else if (utils.isString(data)) {
         data = new Buffer(data, 'utf-8');
       } else {
         return reject(createError(
-          'Data after transformation must be a string, an ArrayBuffer, or a Stream',
+          'Data after transformation must be a string, an ArrayBuffer, a Buffer, or a Stream',
           config
         ));
       }

lib/defaults.js

@@ -32,6 +32,7 @@ var defaults = {
     normalizeHeaderName(headers, 'Content-Type');
     if (utils.isFormData(data) ||
       utils.isArrayBuffer(data) ||
+      utils.isBuffer(data) ||
       utils.isStream(data) ||
       utils.isFile(data) ||
       utils.isBlob(data)

lib/utils.js

@@ -18,6 +18,16 @@ function isArray(val) {
   return toString.call(val) === '[object Array]';
 }
 
+/**
+ * Determine if a value is a Node Buffer
+ *
+ * @param {Object} val The value to test
+ * @returns {boolean} True if value is a Node Buffer, otherwise false
+ */
+function isBuffer(val) {
+  return ((typeof Buffer !== 'undefined') && (Buffer.isBuffer) && (Buffer.isBuffer(val)));
+}
+
 /**
  * Determine if a value is an ArrayBuffer
  *
@@ -281,6 +291,7 @@ function extend(a, b, thisArg) {
 module.exports = {
   isArray: isArray,
   isArrayBuffer: isArrayBuffer,
+  isBuffer: isBuffer,
   isFormData: isFormData,
   isArrayBufferView: isArrayBufferView,
   isString: isString,

test/unit/adapters/http.js

@@ -248,6 +248,30 @@ module.exports = {
     });
   },
 
+  testBuffer: function(test) {
+    var buf = new Buffer(1024); // Unsafe buffer < Buffer.poolSize (8192 bytes)
+    buf.fill('x');
+    server = http.createServer(function (req, res) {
+      test.equal(req.headers['content-length'], buf.length.toString());
+      req.pipe(res);
+    }).listen(4444, function () {
+      axios.post('http://localhost:4444/',
+        buf, {
+        responseType: 'stream'
+      }).then(function (res) {
+        var stream = res.data;
+        var string = '';
+        stream.on('data', function (chunk) {
+          string += chunk.toString('utf8');
+        });
+        stream.on('end', function () {
+          test.equal(string, buf.toString());
+          test.done();
+        });
+      });
+    });
+  },
+
   testHTTPProxy: function(test) {
     server = http.createServer(function(req, res) {
       res.setHeader('Content-Type', 'text/html; charset=UTF-8');