google-closure-library
Version:
Google's common JavaScript library
267 lines (232 loc) • 8.57 kB
JavaScript
/**
* @license
* Copyright The Closure Library Authors.
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @fileoverview Protocol Buffer 2 Serializer which serializes messages
* into anonymous, simplified JSON objects.
*/
goog.provide('goog.proto2.ObjectSerializer');
goog.require('goog.asserts');
goog.require('goog.proto2.FieldDescriptor');
goog.require('goog.proto2.Serializer');
goog.require('goog.string');
goog.requireType('goog.proto2.Message');
/**
* ObjectSerializer, a serializer which turns Messages into simplified
* ECMAScript objects.
*
* @param {goog.proto2.ObjectSerializer.KeyOption=} opt_keyOption If specified,
* which key option to use when serializing/deserializing.
* @param {boolean=} opt_serializeBooleanAsNumber If specified and true, the
* serializer will convert boolean values to 0/1 representation.
* @param {boolean=} opt_ignoreUnknownFields If specified and true, the
* serializer will ignore unknown fields in the JSON payload instead of
* returning an error.
* @constructor
* @extends {goog.proto2.Serializer}
*/
goog.proto2.ObjectSerializer = function(
opt_keyOption, opt_serializeBooleanAsNumber, opt_ignoreUnknownFields) {
'use strict';
/** @const */
this.keyOption_ = opt_keyOption;
/** @const */
this.serializeBooleanAsNumber_ = opt_serializeBooleanAsNumber;
/** @const */
this.ignoreUnknownFields_ = opt_ignoreUnknownFields;
};
goog.inherits(goog.proto2.ObjectSerializer, goog.proto2.Serializer);
/**
* An enumeration of the options for how to emit the keys in
* the generated simplified object.
*
* For serialization, the option specifies the keys to use in the serialized
* object.
*
* For deserialization, the option specifies which keys are allowed; an object
* serialized by TAG may be deserialized by TAG or by NAME or by
* CAMEL_CASE_NAME, but an object serialized by NAME cannot be deserialized by
* TAG. An object serialized with any option can be deserialized by
* CAMEL_CASE_NAME.
*
* @enum {number}
*/
goog.proto2.ObjectSerializer.KeyOption = {
/**
* Use the tag of the field as the key (default)
*/
TAG: 0,
/**
* Use the name of the field as the key. Unknown fields
* will still use their tags as keys.
*/
NAME: 1,
/**
* Use the camel cased name of the field as the key.
* Unknown fields will still use their tags as keys.
*/
CAMEL_CASE_NAME: 2
};
/**
* Serializes a message to an object.
*
* @param {goog.proto2.Message} message The message to be serialized.
* @return {!Object} The serialized form of the message.
* @override
*/
goog.proto2.ObjectSerializer.prototype.serialize = function(message) {
'use strict';
var descriptor = message.getDescriptor();
var fields = descriptor.getFields();
var objectValue = {};
// Add the defined fields, recursively.
for (var i = 0; i < fields.length; i++) {
var field = fields[i];
var key = field.getTag();
switch (this.keyOption_) {
case goog.proto2.ObjectSerializer.KeyOption.TAG:
// no action necessary, key already has the correct value.
break;
case goog.proto2.ObjectSerializer.KeyOption.NAME:
key = field.getName();
break;
case goog.proto2.ObjectSerializer.KeyOption.CAMEL_CASE_NAME:
key = goog.string.toCamelCase(
field
.getName()
// goog.string.toCamelCase expects a hyphen delimited string but
// proto fields are usually underscore delimited
// (go/proto-style-guide); the following regex converts from
// underscore delimited form to hyphen delimited form.
.replace(/_/g, '-'));
break;
default:
// Default should never be reached unless keyOption is outside the valid
// domain.
goog.asserts.assert(
this.keyOption_ !== goog.proto2.ObjectSerializer.KeyOption.TAG &&
this.keyOption_ !==
goog.proto2.ObjectSerializer.KeyOption.NAME &&
this.keyOption_ !==
goog.proto2.ObjectSerializer.KeyOption.CAMEL_CASE_NAME,
'keyOption should be one of TAG, NAME, or CAMEL_CASE_NAME');
}
if (message.has(field)) {
if (field.isRepeated()) {
var array = [];
objectValue[key] = array;
for (var j = 0; j < message.countOf(field); j++) {
array.push(this.getSerializedValue(field, message.get(field, j)));
}
} else {
objectValue[key] = this.getSerializedValue(field, message.get(field));
}
}
}
// Add the unknown fields, if any.
message.forEachUnknown(function(tag, value) {
'use strict';
// Do not set null values. This is possible when using pbliteserializer to
// convert jsbp to closure object and then passed to this method.
if (value !== null) {
objectValue[tag] = value;
}
});
return objectValue;
};
/** @override */
goog.proto2.ObjectSerializer.prototype.getSerializedValue = function(
field, value) {
'use strict';
// Handle the case where a boolean should be serialized as 0/1.
// Some deserialization libraries, such as GWT, can use this notation.
if (this.serializeBooleanAsNumber_ &&
field.getFieldType() == goog.proto2.FieldDescriptor.FieldType.BOOL &&
typeof value === 'boolean') {
return value ? 1 : 0;
}
return goog.proto2.ObjectSerializer.base(
this, 'getSerializedValue', field, value);
};
/** @override */
goog.proto2.ObjectSerializer.prototype.getDeserializedValue = function(
field, value) {
'use strict';
// Gracefully handle the case where a boolean is represented by 0/1.
// Some serialization libraries, such as GWT, can use this notation.
if (field.getFieldType() == goog.proto2.FieldDescriptor.FieldType.BOOL &&
typeof value === 'number') {
return Boolean(value);
}
return goog.proto2.ObjectSerializer.base(
this, 'getDeserializedValue', field, value);
};
/**
* Deserializes a message from an object and places the
* data in the message.
*
* @param {goog.proto2.Message} message The message in which to
* place the information.
* @param {*} data The data of the message.
* @override
*/
goog.proto2.ObjectSerializer.prototype.deserializeTo = function(message, data) {
'use strict';
var descriptor = message.getDescriptor();
for (var key in data) {
var field;
var value = data[key];
var isNumeric = goog.string.isNumeric(key);
if (isNumeric) {
field = descriptor.findFieldByTag(key);
} else {
// We must not be in Key == TAG mode to lookup by name.
goog.asserts.assert(
this.keyOption_ == goog.proto2.ObjectSerializer.KeyOption.NAME ||
this.keyOption_ ==
goog.proto2.ObjectSerializer.KeyOption.CAMEL_CASE_NAME,
'Key mode ' + this.keyOption_ + 'for key ' + key + ' is not ' +
goog.proto2.ObjectSerializer.KeyOption.NAME + ' nor ' +
goog.proto2.ObjectSerializer.KeyOption.CAMEL_CASE_NAME);
if (this.keyOption_ ==
goog.proto2.ObjectSerializer.KeyOption.CAMEL_CASE_NAME) {
key = goog.string
.toSelectorCase(key)
// goog.string.toSelectorCase returns a hyphen delimited form
// of the name but protos usually use an underscore delimited
// form (go/proto-style-guide); the following regex converts
// from hyphens to underscores.
.replace(/\-/g, '_');
}
field = descriptor.findFieldByName(key);
}
if (field) {
if (field.isRepeated()) {
goog.asserts.assert(
Array.isArray(value),
'Value for repeated field ' + field + ' must be an array.');
for (var j = 0; j < value.length; j++) {
message.add(field, this.getDeserializedValue(field, value[j]));
}
} else {
goog.asserts.assert(
!Array.isArray(value),
'Value for non-repeated field ' + field + ' must not be an array.');
message.set(field, this.getDeserializedValue(field, value));
}
} else {
if (isNumeric) {
// We have an unknown field (with a numeric tag).
message.setUnknown(Number(key), value);
} else {
// Handle unknown non-numeric tag.
if (!this.ignoreUnknownFields_) {
// Named fields must be present.
goog.asserts.fail('Failed to find field: ' + key);
}
}
}
}
};