Allow setting connection timezone and honor UTC For Date/DateTime

This resolves sidorares#262

if timezone is set, we change the timezone of the connection upon opening.

If timezone is set to utc and not using dateStrings, we create Date objects
using UTC mode instead.

Also discovered missing config keys that affect packet parsers not
being included in the cache key for packet parser cache, so added them.

lib/connection.js

@@ -124,6 +124,13 @@ function Connection(opts) {
       connection._notifyError(err);
     });
     this.addCommand(handshakeCommand);
+    if (this.config.timezone && this.config.timezone !== 'local') {
+      this.query("SET time_zone = ?", [this.config.timezone], function (err) {
+        if (err) {
+          connection._notifyError(err);
+        }
+      });
+    }
   }
 
   // in case there was no initiall handshake but we need to read sting, assume it utf-8

lib/connection_config.js

@@ -31,7 +31,7 @@ function ConnectionConfig(options) {
   this.debug = options.debug;
   this.trace = options.trace !== false;
   this.stringifyObjects = options.stringifyObjects || false;
-  this.timezone = options.timezone || 'local';
+  this.timezone = (options.timezone || 'local').toLowerCase();
   this.queryFormat = options.queryFormat;
   this.pool = options.pool || undefined;
   this.ssl = typeof options.ssl === 'string'

lib/packets/packet.js

@@ -258,6 +258,37 @@ Packet.prototype.readDateTime = function() {
   return new Date(y, m - 1, d, H, M, S, ms);
 };
 
+Packet.prototype.readUTCDateTime = function() {
+  var length = this.readInt8();
+  if (length == 0xfb) {
+    return null;
+  }
+  var y = 0;
+  var m = 0;
+  var d = 0;
+  var H = 0;
+  var M = 0;
+  var S = 0;
+  var ms = 0;
+  if (length > 3) {
+    y = this.readInt16();
+    m = this.readInt8();
+    d = this.readInt8();
+  }
+  if (length > 6) {
+    H = this.readInt8();
+    M = this.readInt8();
+    S = this.readInt8();
+  }
+  if (length > 10) {
+    ms = this.readInt32() / 1000;
+  }
+  if (y + m + d + H + M + S + ms === 0) {
+    return INVALID_DATE;
+  }
+  return new Date(Date.UTC(y, m - 1, d, H, M, S, ms));
+};
+
 // this is nearly duplicate of previous function so generated code is not slower
 // due to "if (dateStrings)" branching
 var pad = '000000000000';
@@ -613,6 +644,25 @@ Packet.prototype.parseDate = function() {
   return new Date(y, m - 1, d);
 };
 
+Packet.prototype.parseUTCDate = function() {
+  var strLen = this.readLengthCodedNumber();
+  if (strLen === null) {
+    return null;
+  }
+
+  if (strLen != 10) {
+    // we expect only YYYY-MM-DD here.
+    // if for some reason it's not the case return invalid date
+    return new Date(NaN);
+  }
+  var y = this.parseInt(4);
+  this.offset++; // -
+  var m = this.parseInt(2);
+  this.offset++; // -
+  var d = this.parseInt(2);
+  return new Date(Date.UTC(y, m - 1, d));
+};
+
 Packet.prototype.parseDateTime = function() {
   var str = this.readLengthCodedString('binary');
   if (str === null) {
@@ -621,6 +671,14 @@ Packet.prototype.parseDateTime = function() {
   return new Date(str);
 };
 
+Packet.prototype.parseUTCDateTime = function() {
+  var str = this.readLengthCodedString('binary');
+  if (str === null) {
+    return null;
+  }
+  return new Date(Date.UTC(str));
+};
+
 // TODO: handle E notation
 var dot = '.'.charCodeAt(0);
 var exponent = 'e'.charCodeAt(0);

lib/parsers/binary_parser.js

@@ -138,6 +138,9 @@ function readCodeFor(field, config, options, fieldNum) {
       if (config.dateStrings) {
         return 'packet.readDateTimeString(' + field.decimals + ');';
       }
+      if (config.timezone === 'utc') {
+        return 'packet.readUTCDateTime();';
+      }
       return 'packet.readDateTime();';
     case Types.TIME:
       return 'packet.readTimeString()';

lib/parsers/parser_cache.js

@@ -4,7 +4,7 @@ var parserCache = new LRU({
   max: 15000
 });
 
-function keyFromFields(type, fields, options) {
+function keyFromFields(type, fields, options, config) {
   var res =
     type +
     '/' +
@@ -13,20 +13,27 @@ function keyFromFields(type, fields, options) {
     options.nestTables +
     '/' +
     options.rowsAsArray +
-    options.supportBigNumbers +
+    (options.supportBigNumbers || config.supportBigNumbers) +
     '/' +
-    options.bigNumberStrings +
+    (options.bigNumberStrings || config.bigNumberStrings) +
     '/' +
-    typeof options.typeCast;
+    typeof options.typeCast +
+    '/' +
+    options.timezone +
+    '/' +
+    options.decimalNumbers +
+    '/' +
+    options.dateStrings;
   for (var i = 0; i < fields.length; ++i) {
+    var field = fields[i];
     res +=
-      '/' + fields[i].name + ':' + fields[i].columnType + ':' + fields[i].flags;
+      '/' + field.name + ':' + field.columnType + ':' + field.flags + ':' + field.characterSet;
   }
   return res;
 }
 
 function getParser(type, fields, options, config, compiler) {
-  var key = keyFromFields(type, fields, options);
+  var key = keyFromFields(type, fields, options, config);
   var parser = parserCache.get(key);
 
   if (parser) {

lib/parsers/text_parser.js

@@ -165,12 +165,18 @@ function readCodeFor(type, charset, encodingExpr, config, options) {
       if (config.dateStrings) {
         return 'packet.readLengthCodedString("ascii")';
       }
+      if (config.timezone === 'utc') {
+        return 'packet.parseUTCDate()';
+      }
       return 'packet.parseDate()';
     case Types.DATETIME:
     case Types.TIMESTAMP:
       if (config.dateStrings) {
         return 'packet.readLengthCodedString("ascii")';
       }
+      if (config.timezone === 'utc') {
+        return 'packet.parseUTCDateTime();';
+      }
       return 'packet.parseDateTime()';
     case Types.TIME:
       return 'packet.readLengthCodedString("ascii")';