Refactor message format codes handling (#45)

copy-to.js

@@ -4,6 +4,7 @@ module.exports = function(txt, options) {
 
 var Transform = require('stream').Transform
 var util = require('util')
+var code = require('./message-formats')
 
 var CopyStreamQuery = function(text, options) {
   Transform.call(this, options)
@@ -23,13 +24,6 @@ CopyStreamQuery.prototype.submit = function(connection) {
   connection.stream.pipe(this)
 }
 
-var code = {
-  E: 69, //Error
-  H: 72, //CopyOutResponse
-  d: 0x64, //CopyData
-  c: 0x63 //CopyDone
-}
-
 CopyStreamQuery.prototype._detach = function() {
   this.connection.stream.unpipe(this)
   // Unpipe can drop us out of flowing mode
@@ -44,13 +38,13 @@ CopyStreamQuery.prototype._transform = function(chunk, enc, cb) {
   }
   if(!this._copyOutResponse) {
     this._copyOutResponse = true
-    if(chunk[0] == code.E) {
+    if(chunk[0] == code.ErrorResponse) {
       this._detach()
       this.push(null)
       return cb();
     }
-    if(chunk[0] != code.H) {
-      this.emit('error', new Error('Expected copy out response'))
+    if(chunk[0] != code.CopyOutResponse) {
+      this.emit('error', new Error('Expected CopyOutResponse code (H)'))
     }
     var length = chunk.readUInt32BE(1)
     offset = 1
@@ -59,14 +53,14 @@ CopyStreamQuery.prototype._transform = function(chunk, enc, cb) {
   while((chunk.length - offset) > 5) {
     var messageCode = chunk[offset]
     //complete or error
-    if(messageCode == code.c || messageCode == code.E) {
+    if(messageCode == code.CopyDone || messageCode == code.ErrorResponse) {
       this._detach()
       this.push(null)
       return cb();
     }
     //something bad happened
-    if(messageCode != code.d) {
-      return this.emit('error', new Error('expected "d" (copydata message)'))
+    if(messageCode != code.CopyData) {
+      return this.emit('error', new Error('Expected CopyData code (d)'))
     }
     var length = chunk.readUInt32BE(offset + 1) - 4 //subtract length of UInt32
     //can we read the next row?