src/vom/type-encoder.js - release.js.core - Git at Google

 // Copyright 2015 The Vanadium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style
 // license that can be found in the LICENSE file.

 /**
  * @fileoverview Type encoder maintains a mapping of types to type ids and
  * assists in encoding types on the VOM stream.
  * @private
  */

 module.exports = TypeEncoder;

 var kind = require('../vdl/kind.js');
 var stringify = require('../vdl/stringify.js');
 var canonicalize = require('../vdl/canonicalize.js');
 var util = require('../vdl/util.js');
 var BootstrapTypes = require('./bootstrap-types.js');
 var RawVomWriter = require('./raw-vom-writer.js');
 var unwrap = require('../vdl/type-util').unwrap;
 var wiretype = require('../gen-vdl/v.io/v23/vom');

 var endByte = unwrap(wiretype.WireCtrlEnd);

 /**
  * Create a type encoder to help encode types and associate already sent types
  * to their type ids.
  * @constructor
  * @param {module:vanadium.vom.ByteMessageWriter} messageWriter The message
  * writer to write to.
  * @param {function} flush A function that will be called every time a type
  * message has been written.  An example is to write copy the bytes in
  * messageWriter to the wire every time a type message is written.
  * @memberof module:vanadium.vom
  */
 function TypeEncoder(messageWriter, flush) {
   this._typeIds = {};
   // TODO(bjornick): Use the vdl output after we fix:
   // https://github.com/veyron/release-issues/issues/1109
   this._nextId = unwrap(wiretype.WireIdFirstUserType);
   this._messageWriter = messageWriter;
   this._flush = flush;
 }

 /**
  * Encode a type on the specified message writer.
  * @param {module:vanadium.vom.Type} type The type to encode.
  * @return {number} The type id of the encoded type.
  */
 TypeEncoder.prototype.encodeType = function(type) {
   var pending = {};
   return this._encodeType(type, pending);
 };

 TypeEncoder.prototype._encodeType = function(type, pending) {
   if (typeof type !== 'object') {
     throw new Error('Type must be an object, but instead had value ' + type);
   }

   // This isn't a bootstrap type, so it needs to be canonicalized.
   if (!Object.isFrozen(type)) {
     type = canonicalize.type(type);
   }

   var stringifiedType = stringify(type);

   var id = BootstrapTypes.typeStringToId(stringifiedType);
   if (id !== undefined) {
     return id;
   }

   // Check the cache of types that have been encoded already.
   id = this._typeIds[stringifiedType];
   if (id !== undefined) {
     return id;
   }

   // This type wasn't in the cache. Update it, and encode the type.
   var typeId = this._nextId++;
   this._typeIds[stringifiedType] = typeId;
   this._encodeWireType(type, typeId, pending);
   if (this._flush) {
     this._flush();
   }
   return typeId;
 };

 var kindToBootstrapType = function(k) {
   switch (k) {
     case kind.ANY:
       return BootstrapTypes.definitions.ANY;
     case kind.BOOL:
       return BootstrapTypes.definitions.BOOL;
     case kind.BYTE:
       return BootstrapTypes.definitions.BYTE;
     case kind.UINT16:
       return BootstrapTypes.definitions.UINT16;
     case kind.UINT32:
       return BootstrapTypes.definitions.UINT32;
     case kind.UINT64:
       return BootstrapTypes.definitions.UINT64;
     case kind.INT8:
       return BootstrapTypes.definitions.INT8;
     case kind.INT16:
       return BootstrapTypes.definitions.INT16;
     case kind.INT32:
       return BootstrapTypes.definitions.INT32;
     case kind.INT64:
       return BootstrapTypes.definitions.INT64;
     case kind.FLOAT32:
       return BootstrapTypes.definitions.FLOAT32;
     case kind.FLOAT64:
       return BootstrapTypes.definitions.FLOAT64;
     case kind.COMPLEX64:
       return BootstrapTypes.definitions.COMPLEX64;
     case kind.COMPLEX128:
       return BootstrapTypes.definitions.COMPLEX128;
     case kind.STRING:
       return BootstrapTypes.definitions.STRING;
     case kind.TYPEOBJECT:
       return BootstrapTypes.definitions.TYPEOBJECT;
     default:
       throw new Error('expected primitive kind ' + kind);
   }
 };

 /**
  * Write a wiretype description to the message writer.
  * @private
  * @param {MessageWriter} messageWriter the message writer.
  * @param {Type} type the type of the message.
  * @param {number} typeId the type id for the type.
  * @param {Set} pending set of types that have been referenced but not sent.
  */
 TypeEncoder.prototype._encodeWireType = function(type, typeId, pending) {
   var stringifiedType = stringify(type);
   pending[stringifiedType] = true;

   var rawWriter = new RawVomWriter();
   var i;
   var elemId;
   var keyId;
   switch (type.kind) {
     case kind.ANY:
     case kind.BOOL:
     case kind.BYTE:
     case kind.UINT16:
     case kind.UINT32:
     case kind.UINT64:
     case kind.INT8:
     case kind.INT16:
     case kind.INT32:
     case kind.INT64:
     case kind.FLOAT32:
     case kind.FLOAT64:
     case kind.COMPLEX64:
     case kind.COMPLEX128:
     case kind.STRING:
     case kind.TYPEOBJECT:
       rawWriter.writeUint(BootstrapTypes.unionIds.NAMED_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(kindToBootstrapType(type.kind).id);
       rawWriter.writeByte(endByte);
       break;
     case kind.OPTIONAL:
       elemId = this._encodeType(type.elem, pending);
       rawWriter.writeUint(BootstrapTypes.unionIds.OPTIONAL_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(elemId);
       rawWriter.writeByte(endByte);
       break;
     case kind.ENUM:
       rawWriter.writeUint(BootstrapTypes.unionIds.ENUM_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(type.labels.length);
       for (i = 0; i < type.labels.length; i++) {
         rawWriter.writeString(type.labels[i]);
       }
       rawWriter.writeByte(endByte);
       break;
     case kind.ARRAY:
       elemId = this._encodeType(type.elem, pending);
       rawWriter.writeUint(BootstrapTypes.unionIds.ARRAY_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(elemId);
       rawWriter.writeUint(2);
       rawWriter.writeUint(type.len);
       rawWriter.writeByte(endByte);
       break;
     case kind.LIST:
       elemId = this._encodeType(type.elem, pending);
       rawWriter.writeUint(BootstrapTypes.unionIds.LIST_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(elemId);
       rawWriter.writeByte(endByte);
       break;
     case kind.SET:
       keyId = this._encodeType(type.key, pending);
       rawWriter.writeUint(BootstrapTypes.unionIds.SET_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(keyId);
       rawWriter.writeByte(endByte);
       break;
     case kind.MAP:
       keyId = this._encodeType(type.key, pending);
       elemId = this._encodeType(type.elem, pending);
       rawWriter.writeUint(BootstrapTypes.unionIds.MAP_TYPE);
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }
       rawWriter.writeUint(1);
       rawWriter.writeUint(keyId);
       rawWriter.writeUint(2);
       rawWriter.writeUint(elemId);
       rawWriter.writeByte(endByte);
       break;
     case kind.STRUCT:
     case kind.UNION:
       var fieldInfo = [];
       for (i = 0; i < type.fields.length; i++) {
         fieldInfo.push({
           name: util.capitalize(type.fields[i].name),
           id: this._encodeType(type.fields[i].type, pending)
         });
       }
       if (type.kind === kind.STRUCT) {
         rawWriter.writeUint(BootstrapTypes.unionIds.STRUCT_TYPE);
       } else {
         rawWriter.writeUint(BootstrapTypes.unionIds.UNION_TYPE);
       }
       if (type.name !== '') {
         rawWriter.writeUint(0);
         rawWriter.writeString(type.name);
       }

       rawWriter.writeUint(1);
       rawWriter.writeUint(fieldInfo.length);
       for (i = 0; i < fieldInfo.length; i++) {
         var field = fieldInfo[i];
         rawWriter.writeUint(0);
         rawWriter.writeString(field.name);
         rawWriter.writeUint(1);
         rawWriter.writeUint(field.id);
         rawWriter.writeByte(endByte);
       }
       rawWriter.writeByte(endByte);
       break;
     default:
       throw new Error('encodeWireType with unknown kind: ' + type.kind);
   }

   delete pending[stringifiedType];
   var seen = {};
   var isIncomplete = _typeIncomplete(type, pending, seen);
   this._messageWriter.writeTypeMessage(typeId, rawWriter.getBytes(),
     isIncomplete);
 };

 function _typeIncomplete(type, pending, seen) {
   var stringifiedType = stringify(type);
   if (seen.hasOwnProperty(stringifiedType)) {
     return false;
   }
   seen[stringifiedType] = true;
   if (pending.hasOwnProperty(stringifiedType)) {
     return true;
   }
   switch (type.kind) {
     case kind.OPTIONAL:
     case kind.ARRAY:
     case kind.LIST:
       return _typeIncomplete(type.elem, pending, seen);
     case kind.SET:
     return _typeIncomplete(type.key, pending, seen);
     case kind.MAP:
     return _typeIncomplete(type.key, pending, seen) ||
       _typeIncomplete(type.elem, pending, seen);
     case kind.STRUCT:
     case kind.UNION:
       for (var i = 0; i < type.fields.length; i++) {
         if (_typeIncomplete(type.fields[i].type, pending, seen)) {
           return true;
         }
       }
       return false;
     default:
       return false;
   }
 }
	// Copyright 2015 The Vanadium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style
	// license that can be found in the LICENSE file.

	/**
	* @fileoverview Type encoder maintains a mapping of types to type ids and
	* assists in encoding types on the VOM stream.
	* @private
	*/

	module.exports = TypeEncoder;

	var kind = require('../vdl/kind.js');
	var stringify = require('../vdl/stringify.js');
	var canonicalize = require('../vdl/canonicalize.js');
	var util = require('../vdl/util.js');
	var BootstrapTypes = require('./bootstrap-types.js');
	var RawVomWriter = require('./raw-vom-writer.js');
	var unwrap = require('../vdl/type-util').unwrap;
	var wiretype = require('../gen-vdl/v.io/v23/vom');

	var endByte = unwrap(wiretype.WireCtrlEnd);

	/**
	* Create a type encoder to help encode types and associate already sent types
	* to their type ids.
	* @constructor
	* @param {module:vanadium.vom.ByteMessageWriter} messageWriter The message
	* writer to write to.
	* @param {function} flush A function that will be called every time a type
	* message has been written. An example is to write copy the bytes in
	* messageWriter to the wire every time a type message is written.
	* @memberof module:vanadium.vom
	*/
	function TypeEncoder(messageWriter, flush) {
	this._typeIds = {};
	// TODO(bjornick): Use the vdl output after we fix:
	// https://github.com/veyron/release-issues/issues/1109
	this._nextId = unwrap(wiretype.WireIdFirstUserType);
	this._messageWriter = messageWriter;
	this._flush = flush;
	}

	/**
	* Encode a type on the specified message writer.
	* @param {module:vanadium.vom.Type} type The type to encode.
	* @return {number} The type id of the encoded type.
	*/
	TypeEncoder.prototype.encodeType = function(type) {
	var pending = {};
	return this._encodeType(type, pending);
	};

	TypeEncoder.prototype._encodeType = function(type, pending) {
	if (typeof type !== 'object') {
	throw new Error('Type must be an object, but instead had value ' + type);
	}

	// This isn't a bootstrap type, so it needs to be canonicalized.
	if (!Object.isFrozen(type)) {
	type = canonicalize.type(type);
	}

	var stringifiedType = stringify(type);

	var id = BootstrapTypes.typeStringToId(stringifiedType);
	if (id !== undefined) {
	return id;
	}

	// Check the cache of types that have been encoded already.
	id = this._typeIds[stringifiedType];
	if (id !== undefined) {
	return id;
	}

	// This type wasn't in the cache. Update it, and encode the type.
	var typeId = this._nextId++;
	this._typeIds[stringifiedType] = typeId;
	this._encodeWireType(type, typeId, pending);
	if (this._flush) {
	this._flush();
	}
	return typeId;
	};

	var kindToBootstrapType = function(k) {
	switch (k) {
	case kind.ANY:
	return BootstrapTypes.definitions.ANY;
	case kind.BOOL:
	return BootstrapTypes.definitions.BOOL;
	case kind.BYTE:
	return BootstrapTypes.definitions.BYTE;
	case kind.UINT16:
	return BootstrapTypes.definitions.UINT16;
	case kind.UINT32:
	return BootstrapTypes.definitions.UINT32;
	case kind.UINT64:
	return BootstrapTypes.definitions.UINT64;
	case kind.INT8:
	return BootstrapTypes.definitions.INT8;
	case kind.INT16:
	return BootstrapTypes.definitions.INT16;
	case kind.INT32:
	return BootstrapTypes.definitions.INT32;
	case kind.INT64:
	return BootstrapTypes.definitions.INT64;
	case kind.FLOAT32:
	return BootstrapTypes.definitions.FLOAT32;
	case kind.FLOAT64:
	return BootstrapTypes.definitions.FLOAT64;
	case kind.COMPLEX64:
	return BootstrapTypes.definitions.COMPLEX64;
	case kind.COMPLEX128:
	return BootstrapTypes.definitions.COMPLEX128;
	case kind.STRING:
	return BootstrapTypes.definitions.STRING;
	case kind.TYPEOBJECT:
	return BootstrapTypes.definitions.TYPEOBJECT;
	default:
	throw new Error('expected primitive kind ' + kind);
	}
	};

	/**
	* Write a wiretype description to the message writer.
	* @private
	* @param {MessageWriter} messageWriter the message writer.
	* @param {Type} type the type of the message.
	* @param {number} typeId the type id for the type.
	* @param {Set} pending set of types that have been referenced but not sent.
	*/
	TypeEncoder.prototype._encodeWireType = function(type, typeId, pending) {
	var stringifiedType = stringify(type);
	pending[stringifiedType] = true;

	var rawWriter = new RawVomWriter();
	var i;
	var elemId;
	var keyId;
	switch (type.kind) {
	case kind.ANY:
	case kind.BOOL:
	case kind.BYTE:
	case kind.UINT16:
	case kind.UINT32:
	case kind.UINT64:
	case kind.INT8:
	case kind.INT16:
	case kind.INT32:
	case kind.INT64:
	case kind.FLOAT32:
	case kind.FLOAT64:
	case kind.COMPLEX64:
	case kind.COMPLEX128:
	case kind.STRING:
	case kind.TYPEOBJECT:
	rawWriter.writeUint(BootstrapTypes.unionIds.NAMED_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(kindToBootstrapType(type.kind).id);
	rawWriter.writeByte(endByte);
	break;
	case kind.OPTIONAL:
	elemId = this._encodeType(type.elem, pending);
	rawWriter.writeUint(BootstrapTypes.unionIds.OPTIONAL_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(elemId);
	rawWriter.writeByte(endByte);
	break;
	case kind.ENUM:
	rawWriter.writeUint(BootstrapTypes.unionIds.ENUM_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(type.labels.length);
	for (i = 0; i < type.labels.length; i++) {
	rawWriter.writeString(type.labels[i]);
	}
	rawWriter.writeByte(endByte);
	break;
	case kind.ARRAY:
	elemId = this._encodeType(type.elem, pending);
	rawWriter.writeUint(BootstrapTypes.unionIds.ARRAY_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(elemId);
	rawWriter.writeUint(2);
	rawWriter.writeUint(type.len);
	rawWriter.writeByte(endByte);
	break;
	case kind.LIST:
	elemId = this._encodeType(type.elem, pending);
	rawWriter.writeUint(BootstrapTypes.unionIds.LIST_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(elemId);
	rawWriter.writeByte(endByte);
	break;
	case kind.SET:
	keyId = this._encodeType(type.key, pending);
	rawWriter.writeUint(BootstrapTypes.unionIds.SET_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(keyId);
	rawWriter.writeByte(endByte);
	break;
	case kind.MAP:
	keyId = this._encodeType(type.key, pending);
	elemId = this._encodeType(type.elem, pending);
	rawWriter.writeUint(BootstrapTypes.unionIds.MAP_TYPE);
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}
	rawWriter.writeUint(1);
	rawWriter.writeUint(keyId);
	rawWriter.writeUint(2);
	rawWriter.writeUint(elemId);
	rawWriter.writeByte(endByte);
	break;
	case kind.STRUCT:
	case kind.UNION:
	var fieldInfo = [];
	for (i = 0; i < type.fields.length; i++) {
	fieldInfo.push({
	name: util.capitalize(type.fields[i].name),
	id: this._encodeType(type.fields[i].type, pending)
	});
	}
	if (type.kind === kind.STRUCT) {
	rawWriter.writeUint(BootstrapTypes.unionIds.STRUCT_TYPE);
	} else {
	rawWriter.writeUint(BootstrapTypes.unionIds.UNION_TYPE);
	}
	if (type.name !== '') {
	rawWriter.writeUint(0);
	rawWriter.writeString(type.name);
	}

	rawWriter.writeUint(1);
	rawWriter.writeUint(fieldInfo.length);
	for (i = 0; i < fieldInfo.length; i++) {
	var field = fieldInfo[i];
	rawWriter.writeUint(0);
	rawWriter.writeString(field.name);
	rawWriter.writeUint(1);
	rawWriter.writeUint(field.id);
	rawWriter.writeByte(endByte);
	}
	rawWriter.writeByte(endByte);
	break;
	default:
	throw new Error('encodeWireType with unknown kind: ' + type.kind);
	}

	delete pending[stringifiedType];
	var seen = {};
	var isIncomplete = _typeIncomplete(type, pending, seen);
	this._messageWriter.writeTypeMessage(typeId, rawWriter.getBytes(),
	isIncomplete);
	};

	function _typeIncomplete(type, pending, seen) {
	var stringifiedType = stringify(type);
	if (seen.hasOwnProperty(stringifiedType)) {
	return false;
	}
	seen[stringifiedType] = true;
	if (pending.hasOwnProperty(stringifiedType)) {
	return true;
	}
	switch (type.kind) {
	case kind.OPTIONAL:
	case kind.ARRAY:
	case kind.LIST:
	return _typeIncomplete(type.elem, pending, seen);
	case kind.SET:
	return _typeIncomplete(type.key, pending, seen);
	case kind.MAP:
	return _typeIncomplete(type.key, pending, seen) \|\|
	_typeIncomplete(type.elem, pending, seen);
	case kind.STRUCT:
	case kind.UNION:
	for (var i = 0; i < type.fields.length; i++) {
	if (_typeIncomplete(type.fields[i].type, pending, seen)) {
	return true;
	}
	}
	return false;
	default:
	return false;
	}
	}