// Copyright 2013 The Closure Library Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS-IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/**
* @fileoverview The SafeHtml type and its builders.
*
* TODO(xtof): Link to document stating type contract.
*/
goog.provide('goog.html.SafeHtml');
goog.require('goog.array');
goog.require('goog.asserts');
goog.require('goog.dom.TagName');
goog.require('goog.dom.tags');
goog.require('goog.html.SafeStyle');
goog.require('goog.html.SafeStyleSheet');
goog.require('goog.html.SafeUrl');
goog.require('goog.html.TrustedResourceUrl');
goog.require('goog.i18n.bidi.Dir');
goog.require('goog.i18n.bidi.DirectionalString');
goog.require('goog.object');
goog.require('goog.string');
goog.require('goog.string.Const');
goog.require('goog.string.TypedString');
/**
* A string that is safe to use in HTML context in DOM APIs and HTML documents.
*
* A SafeHtml is a string-like object that carries the security type contract
* that its value as a string will not cause untrusted script execution when
* evaluated as HTML in a browser.
*
* Values of this type are guaranteed to be safe to use in HTML contexts,
* such as, assignment to the innerHTML DOM property, or interpolation into
* a HTML template in HTML PC_DATA context, in the sense that the use will not
* result in a Cross-Site-Scripting vulnerability.
*
* Instances of this type must be created via the factory methods
* ({@code goog.html.SafeHtml.create}, {@code goog.html.SafeHtml.htmlEscape}),
* etc and not by invoking its constructor. The constructor intentionally
* takes no parameters and the type is immutable; hence only a default instance
* corresponding to the empty string can be obtained via constructor invocation.
*
* @see goog.html.SafeHtml#create
* @see goog.html.SafeHtml#htmlEscape
* @constructor
* @final
* @struct
* @implements {goog.i18n.bidi.DirectionalString}
* @implements {goog.string.TypedString}
*/
goog.html.SafeHtml = function() {
/**
* The contained value of this SafeHtml. The field has a purposely ugly
* name to make (non-compiled) code that attempts to directly access this
* field stand out.
* @private {string}
*/
this.privateDoNotAccessOrElseSafeHtmlWrappedValue_ = '';
/**
* A type marker used to implement additional run-time type checking.
* @see goog.html.SafeHtml#unwrap
* @const
* @private
*/
this.SAFE_HTML_TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ =
goog.html.SafeHtml.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_;
/**
* This SafeHtml's directionality, or null if unknown.
* @private {?goog.i18n.bidi.Dir}
*/
this.dir_ = null;
};
/**
* @override
* @const
*/
goog.html.SafeHtml.prototype.implementsGoogI18nBidiDirectionalString = true;
/** @override */
goog.html.SafeHtml.prototype.getDirection = function() {
return this.dir_;
};
/**
* @override
* @const
*/
goog.html.SafeHtml.prototype.implementsGoogStringTypedString = true;
/**
* Returns this SafeHtml's value a string.
*
* IMPORTANT: In code where it is security relevant that an object's type is
* indeed {@code SafeHtml}, use {@code goog.html.SafeHtml.unwrap} instead of
* this method. If in doubt, assume that it's security relevant. In particular,
* note that goog.html functions which return a goog.html type do not guarantee
* that the returned instance is of the right type. For example:
*
* <pre>
* var fakeSafeHtml = new String('fake');
* fakeSafeHtml.__proto__ = goog.html.SafeHtml.prototype;
* var newSafeHtml = goog.html.SafeHtml.htmlEscape(fakeSafeHtml);
* // newSafeHtml is just an alias for fakeSafeHtml, it's passed through by
* // goog.html.SafeHtml.htmlEscape() as fakeSafeHtml
* // instanceof goog.html.SafeHtml.
* </pre>
*
* @see goog.html.SafeHtml#unwrap
* @override
*/
goog.html.SafeHtml.prototype.getTypedStringValue = function() {
return this.privateDoNotAccessOrElseSafeHtmlWrappedValue_;
};
if (goog.DEBUG) {
/**
* Returns a debug string-representation of this value.
*
* To obtain the actual string value wrapped in a SafeHtml, use
* {@code goog.html.SafeHtml.unwrap}.
*
* @see goog.html.SafeHtml#unwrap
* @override
*/
goog.html.SafeHtml.prototype.toString = function() {
return 'SafeHtml{' + this.privateDoNotAccessOrElseSafeHtmlWrappedValue_ +
'}';
};
}
/**
* Performs a runtime check that the provided object is indeed a SafeHtml
* object, and returns its value.
* @param {!goog.html.SafeHtml} safeHtml The object to extract from.
* @return {string} The SafeHtml object's contained string, unless the run-time
* type check fails. In that case, {@code unwrap} returns an innocuous
* string, or, if assertions are enabled, throws
* {@code goog.asserts.AssertionError}.
*/
goog.html.SafeHtml.unwrap = function(safeHtml) {
// Perform additional run-time type-checking to ensure that safeHtml is indeed
// an instance of the expected type. This provides some additional protection
// against security bugs due to application code that disables type checks.
// Specifically, the following checks are performed:
// 1. The object is an instance of the expected type.
// 2. The object is not an instance of a subclass.
// 3. The object carries a type marker for the expected type. "Faking" an
// object requires a reference to the type marker, which has names intended
// to stand out in code reviews.
if (safeHtml instanceof goog.html.SafeHtml &&
safeHtml.constructor === goog.html.SafeHtml &&
safeHtml.SAFE_HTML_TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ ===
goog.html.SafeHtml.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_) {
return safeHtml.privateDoNotAccessOrElseSafeHtmlWrappedValue_;
} else {
goog.asserts.fail('expected object of type SafeHtml, got \'' +
safeHtml + '\'');
return 'type_error:SafeHtml';
}
};
/**
* Shorthand for union of types that can sensibly be converted to strings
* or might already be SafeHtml (as SafeHtml is a goog.string.TypedString).
* @private
* @typedef {string|number|boolean|!goog.string.TypedString|
* !goog.i18n.bidi.DirectionalString}
*/
goog.html.SafeHtml.TextOrHtml_;
/**
* Returns HTML-escaped text as a SafeHtml object.
*
* If text is of a type that implements
* {@code goog.i18n.bidi.DirectionalString}, the directionality of the new
* {@code SafeHtml} object is set to {@code text}'s directionality, if known.
* Otherwise, the directionality of the resulting SafeHtml is unknown (i.e.,
* {@code null}).
*
* @param {!goog.html.SafeHtml.TextOrHtml_} textOrHtml The text to escape. If
* the parameter is of type SafeHtml it is returned directly (no escaping
* is done).
* @return {!goog.html.SafeHtml} The escaped text, wrapped as a SafeHtml.
*/
goog.html.SafeHtml.htmlEscape = function(textOrHtml) {
if (textOrHtml instanceof goog.html.SafeHtml) {
return textOrHtml;
}
var dir = null;
if (textOrHtml.implementsGoogI18nBidiDirectionalString) {
dir = textOrHtml.getDirection();
}
var textAsString;
if (textOrHtml.implementsGoogStringTypedString) {
textAsString = textOrHtml.getTypedStringValue();
} else {
textAsString = String(textOrHtml);
}
return goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
goog.string.htmlEscape(textAsString), dir);
};
/**
* Returns HTML-escaped text as a SafeHtml object, with newlines changed to
* <br>.
* @param {!goog.html.SafeHtml.TextOrHtml_} textOrHtml The text to escape. If
* the parameter is of type SafeHtml it is returned directly (no escaping
* is done).
* @return {!goog.html.SafeHtml} The escaped text, wrapped as a SafeHtml.
*/
goog.html.SafeHtml.htmlEscapePreservingNewlines = function(textOrHtml) {
if (textOrHtml instanceof goog.html.SafeHtml) {
return textOrHtml;
}
var html = goog.html.SafeHtml.htmlEscape(textOrHtml);
return goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
goog.string.newLineToBr(goog.html.SafeHtml.unwrap(html)),
html.getDirection());
};
/**
* Returns HTML-escaped text as a SafeHtml object, with newlines changed to
* <br> and escaping whitespace to preserve spatial formatting. Character
* entity #160 is used to make it safer for XML.
* @param {!goog.html.SafeHtml.TextOrHtml_} textOrHtml The text to escape. If
* the parameter is of type SafeHtml it is returned directly (no escaping
* is done).
* @return {!goog.html.SafeHtml} The escaped text, wrapped as a SafeHtml.
*/
goog.html.SafeHtml.htmlEscapePreservingNewlinesAndSpaces = function(
textOrHtml) {
if (textOrHtml instanceof goog.html.SafeHtml) {
return textOrHtml;
}
var html = goog.html.SafeHtml.htmlEscape(textOrHtml);
return goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
goog.string.whitespaceEscape(goog.html.SafeHtml.unwrap(html)),
html.getDirection());
};
/**
* Coerces an arbitrary object into a SafeHtml object.
*
* If {@code textOrHtml} is already of type {@code goog.html.SafeHtml}, the same
* object is returned. Otherwise, {@code textOrHtml} is coerced to string, and
* HTML-escaped. If {@code textOrHtml} is of a type that implements
* {@code goog.i18n.bidi.DirectionalString}, its directionality, if known, is
* preserved.
*
* @param {!goog.html.SafeHtml.TextOrHtml_} textOrHtml The text or SafeHtml to
* coerce.
* @return {!goog.html.SafeHtml} The resulting SafeHtml object.
* @deprecated Use goog.html.SafeHtml.htmlEscape.
*/
goog.html.SafeHtml.from = goog.html.SafeHtml.htmlEscape;
/**
* @const
* @private
*/
goog.html.SafeHtml.VALID_NAMES_IN_TAG_ = /^[a-zA-Z0-9-]+$/;
/**
* Set of attributes containing URL as defined at
* http://www.w3.org/TR/html5/index.html#attributes-1.
* @private @const {!Object<string,boolean>}
*/
goog.html.SafeHtml.URL_ATTRIBUTES_ = goog.object.createSet('action', 'cite',
'data', 'formaction', 'href', 'manifest', 'poster', 'src');
/**
* Tags which are unsupported via create(). They might be supported via a
* tag-specific create method. These are tags which might require a
* TrustedResourceUrl in one of their attributes or a restricted type for
* their content.
* @private @const {!Object<string,boolean>}
*/
goog.html.SafeHtml.NOT_ALLOWED_TAG_NAMES_ = goog.object.createSet(
goog.dom.TagName.EMBED, goog.dom.TagName.IFRAME, goog.dom.TagName.LINK,
goog.dom.TagName.OBJECT, goog.dom.TagName.SCRIPT, goog.dom.TagName.STYLE,
goog.dom.TagName.TEMPLATE);
/**
* @typedef {string|number|goog.string.TypedString|
* goog.html.SafeStyle.PropertyMap}
* @private
*/
goog.html.SafeHtml.AttributeValue_;
/**
* Creates a SafeHtml content consisting of a tag with optional attributes and
* optional content.
*
* For convenience tag names and attribute names are accepted as regular
* strings, instead of goog.string.Const. Nevertheless, you should not pass
* user-controlled values to these parameters. Note that these parameters are
* syntactically validated at runtime, and invalid values will result in
* an exception.
*
* Example usage:
*
* goog.html.SafeHtml.create('br');
* goog.html.SafeHtml.create('div', {'class': 'a'});
* goog.html.SafeHtml.create('p', {}, 'a');
* goog.html.SafeHtml.create('p', {}, goog.html.SafeHtml.create('br'));
*
* goog.html.SafeHtml.create('span', {
* 'style': {'margin': '0'}
* });
*
* To guarantee SafeHtml's type contract is upheld there are restrictions on
* attribute values and tag names.
*
* - For attributes which contain script code (on*), a goog.string.Const is
* required.
* - For attributes which contain style (style), a goog.html.SafeStyle or a
* goog.html.SafeStyle.PropertyMap is required.
* - For attributes which are interpreted as URLs (e.g. src, href) a
* goog.html.SafeUrl, goog.string.Const or string is required. If a string
* is passed, it will be sanitized with SafeUrl.sanitize().
* - For tags which can load code, more specific goog.html.SafeHtml.create*()
* functions must be used. Tags which can load code and are not supported by
* this function are embed, iframe, link, object, script, style, and template.
*
* @param {string} tagName The name of the tag. Only tag names consisting of
* [a-zA-Z0-9-] are allowed. Tag names documented above are disallowed.
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=}
* opt_attributes Mapping from attribute names to their values. Only
* attribute names consisting of [a-zA-Z0-9-] are allowed. Value of null or
* undefined causes the attribute to be omitted.
* @param {!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>=} opt_content Content to
* HTML-escape and put inside the tag. This must be empty for void tags
* like <br>. Array elements are concatenated.
* @return {!goog.html.SafeHtml} The SafeHtml content with the tag.
* @throws {Error} If invalid tag name, attribute name, or attribute value is
* provided.
* @throws {goog.asserts.AssertionError} If content for void tag is provided.
*/
goog.html.SafeHtml.create = function(tagName, opt_attributes, opt_content) {
if (!goog.html.SafeHtml.VALID_NAMES_IN_TAG_.test(tagName)) {
throw Error('Invalid tag name <' + tagName + '>.');
}
if (tagName.toUpperCase() in goog.html.SafeHtml.NOT_ALLOWED_TAG_NAMES_) {
throw Error('Tag name <' + tagName + '> is not allowed for SafeHtml.');
}
return goog.html.SafeHtml.createSafeHtmlTagSecurityPrivateDoNotAccessOrElse(
tagName, opt_attributes, opt_content);
};
/**
* Creates a SafeHtml representing an iframe tag.
*
* By default the sandbox attribute is set to an empty value, which is the most
* secure option, as it confers the iframe the least privileges. If this
* is too restrictive then granting individual privileges is the preferable
* option. Unsetting the attribute entirely is the least secure option and
* should never be done unless it's stricly necessary.
*
* @param {goog.html.TrustedResourceUrl=} opt_src The value of the src
* attribute. If null or undefined src will not be set.
* @param {goog.html.SafeHtml=} opt_srcdoc The value of the srcdoc attribute.
* If null or undefined srcdoc will not be set.
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=}
* opt_attributes Mapping from attribute names to their values. Only
* attribute names consisting of [a-zA-Z0-9-] are allowed. Value of null or
* undefined causes the attribute to be omitted.
* @param {!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>=} opt_content Content to
* HTML-escape and put inside the tag. Array elements are concatenated.
* @return {!goog.html.SafeHtml} The SafeHtml content with the tag.
* @throws {Error} If invalid tag name, attribute name, or attribute value is
* provided. If opt_attributes contains the src or srcdoc attributes.
*/
goog.html.SafeHtml.createIframe = function(
opt_src, opt_srcdoc, opt_attributes, opt_content) {
var fixedAttributes = {};
fixedAttributes['src'] = opt_src || null;
fixedAttributes['srcdoc'] = opt_srcdoc || null;
var defaultAttributes = {'sandbox': ''};
var attributes = goog.html.SafeHtml.combineAttributes(
fixedAttributes, defaultAttributes, opt_attributes);
return goog.html.SafeHtml.createSafeHtmlTagSecurityPrivateDoNotAccessOrElse(
'iframe', attributes, opt_content);
};
/**
* Creates a SafeHtml representing a style tag. The type attribute is set
* to "text/css".
* @param {!goog.html.SafeStyleSheet|!Array<!goog.html.SafeStyleSheet>}
* styleSheet Content to put inside the tag. Array elements are
* concatenated.
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=}
* opt_attributes Mapping from attribute names to their values. Only
* attribute names consisting of [a-zA-Z0-9-] are allowed. Value of null or
* undefined causes the attribute to be omitted.
* @return {!goog.html.SafeHtml} The SafeHtml content with the tag.
* @throws {Error} If invalid attribute name or attribute value is provided. If
* opt_attributes contains the type attribute.
*/
goog.html.SafeHtml.createStyle = function(styleSheet, opt_attributes) {
var fixedAttributes = {'type': 'text/css'};
var defaultAttributes = {};
var attributes = goog.html.SafeHtml.combineAttributes(
fixedAttributes, defaultAttributes, opt_attributes);
var content = '';
styleSheet = goog.array.concat(styleSheet);
for (var i = 0; i < styleSheet.length; i++) {
content += goog.html.SafeStyleSheet.unwrap(styleSheet[i]);
}
// Convert to SafeHtml so that it's not HTML-escaped.
var htmlContent = goog.html.SafeHtml
.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
content, goog.i18n.bidi.Dir.NEUTRAL);
return goog.html.SafeHtml.createSafeHtmlTagSecurityPrivateDoNotAccessOrElse(
'style', attributes, htmlContent);
};
/**
* @param {string} tagName The tag name.
* @param {string} name The attribute name.
* @param {!goog.html.SafeHtml.AttributeValue_} value The attribute value.
* @return {string} A "name=value" string.
* @throws {Error} If attribute value is unsafe for the given tag and attribute.
* @private
*/
goog.html.SafeHtml.getAttrNameAndValue_ = function(tagName, name, value) {
// If it's goog.string.Const, allow any valid attribute name.
if (value instanceof goog.string.Const) {
value = goog.string.Const.unwrap(value);
} else if (name.toLowerCase() == 'style') {
value = goog.html.SafeHtml.getStyleValue_(value);
} else if (/^on/i.test(name)) {
// TODO(jakubvrana): Disallow more attributes with a special meaning.
throw Error('Attribute "' + name +
'" requires goog.string.Const value, "' + value + '" given.');
// URL attributes handled differently accroding to tag.
} else if (name.toLowerCase() in goog.html.SafeHtml.URL_ATTRIBUTES_) {
if (value instanceof goog.html.TrustedResourceUrl) {
value = goog.html.TrustedResourceUrl.unwrap(value);
} else if (value instanceof goog.html.SafeUrl) {
value = goog.html.SafeUrl.unwrap(value);
} else if (goog.isString(value)) {
value = goog.html.SafeUrl.sanitize(value).getTypedStringValue();
} else {
throw Error('Attribute "' + name + '" on tag "' + tagName +
'" requires goog.html.SafeUrl, goog.string.Const, or string,' +
' value "' + value + '" given.');
}
}
// Accept SafeUrl, TrustedResourceUrl, etc. for attributes which only require
// HTML-escaping.
if (value.implementsGoogStringTypedString) {
// Ok to call getTypedStringValue() since there's no reliance on the type
// contract for security here.
value = value.getTypedStringValue();
}
goog.asserts.assert(goog.isString(value) || goog.isNumber(value),
'String or number value expected, got ' +
(typeof value) + ' with value: ' + value);
return name + '="' + goog.string.htmlEscape(String(value)) + '"';
};
/**
* Gets value allowed in "style" attribute.
* @param {goog.html.SafeHtml.AttributeValue_} value It could be SafeStyle or a
* map which will be passed to goog.html.SafeStyle.create.
* @return {string} Unwrapped value.
* @throws {Error} If string value is given.
* @private
*/
goog.html.SafeHtml.getStyleValue_ = function(value) {
if (!goog.isObject(value)) {
throw Error('The "style" attribute requires goog.html.SafeStyle or map ' +
'of style properties, ' + (typeof value) + ' given: ' + value);
}
if (!(value instanceof goog.html.SafeStyle)) {
// Process the property bag into a style object.
value = goog.html.SafeStyle.create(value);
}
return goog.html.SafeStyle.unwrap(value);
};
/**
* Creates a SafeHtml content with known directionality consisting of a tag with
* optional attributes and optional content.
* @param {!goog.i18n.bidi.Dir} dir Directionality.
* @param {string} tagName
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=} opt_attributes
* @param {!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>=} opt_content
* @return {!goog.html.SafeHtml} The SafeHtml content with the tag.
*/
goog.html.SafeHtml.createWithDir = function(dir, tagName, opt_attributes,
opt_content) {
var html = goog.html.SafeHtml.create(tagName, opt_attributes, opt_content);
html.dir_ = dir;
return html;
};
/**
* Creates a new SafeHtml object by concatenating values.
* @param {...(!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>)} var_args Values to concatenate.
* @return {!goog.html.SafeHtml}
*/
goog.html.SafeHtml.concat = function(var_args) {
var dir = goog.i18n.bidi.Dir.NEUTRAL;
var content = '';
/**
* @param {!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>} argument
*/
var addArgument = function(argument) {
if (goog.isArray(argument)) {
goog.array.forEach(argument, addArgument);
} else {
var html = goog.html.SafeHtml.htmlEscape(argument);
content += goog.html.SafeHtml.unwrap(html);
var htmlDir = html.getDirection();
if (dir == goog.i18n.bidi.Dir.NEUTRAL) {
dir = htmlDir;
} else if (htmlDir != goog.i18n.bidi.Dir.NEUTRAL && dir != htmlDir) {
dir = null;
}
}
};
goog.array.forEach(arguments, addArgument);
return goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
content, dir);
};
/**
* Creates a new SafeHtml object with known directionality by concatenating the
* values.
* @param {!goog.i18n.bidi.Dir} dir Directionality.
* @param {...(!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>)} var_args Elements of array
* arguments would be processed recursively.
* @return {!goog.html.SafeHtml}
*/
goog.html.SafeHtml.concatWithDir = function(dir, var_args) {
var html = goog.html.SafeHtml.concat(goog.array.slice(arguments, 1));
html.dir_ = dir;
return html;
};
/**
* Type marker for the SafeHtml type, used to implement additional run-time
* type checking.
* @const
* @private
*/
goog.html.SafeHtml.TYPE_MARKER_GOOG_HTML_SECURITY_PRIVATE_ = {};
/**
* Package-internal utility method to create SafeHtml instances.
*
* @param {string} html The string to initialize the SafeHtml object with.
* @param {?goog.i18n.bidi.Dir} dir The directionality of the SafeHtml to be
* constructed, or null if unknown.
* @return {!goog.html.SafeHtml} The initialized SafeHtml object.
* @package
*/
goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse = function(
html, dir) {
return new goog.html.SafeHtml().initSecurityPrivateDoNotAccessOrElse_(
html, dir);
};
/**
* Called from createSafeHtmlSecurityPrivateDoNotAccessOrElse(). This
* method exists only so that the compiler can dead code eliminate static
* fields (like EMPTY) when they're not accessed.
* @param {string} html
* @param {?goog.i18n.bidi.Dir} dir
* @return {!goog.html.SafeHtml}
* @private
*/
goog.html.SafeHtml.prototype.initSecurityPrivateDoNotAccessOrElse_ = function(
html, dir) {
this.privateDoNotAccessOrElseSafeHtmlWrappedValue_ = html;
this.dir_ = dir;
return this;
};
/**
* Like create() but does not restrict which tags can be constructed.
*
* @param {string} tagName Tag name. Set or validated by caller.
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=} opt_attributes
* @param {(!goog.html.SafeHtml.TextOrHtml_|
* !Array<!goog.html.SafeHtml.TextOrHtml_>)=} opt_content
* @return {!goog.html.SafeHtml}
* @throws {Error} If invalid or unsafe attribute name or value is provided.
* @throws {goog.asserts.AssertionError} If content for void tag is provided.
* @package
*/
goog.html.SafeHtml.createSafeHtmlTagSecurityPrivateDoNotAccessOrElse =
function(tagName, opt_attributes, opt_content) {
var dir = null;
var result = '<' + tagName;
if (opt_attributes) {
for (var name in opt_attributes) {
if (!goog.html.SafeHtml.VALID_NAMES_IN_TAG_.test(name)) {
throw Error('Invalid attribute name "' + name + '".');
}
var value = opt_attributes[name];
if (!goog.isDefAndNotNull(value)) {
continue;
}
result += ' ' +
goog.html.SafeHtml.getAttrNameAndValue_(tagName, name, value);
}
}
var content = opt_content;
if (!goog.isDefAndNotNull(content)) {
content = [];
} else if (!goog.isArray(content)) {
content = [content];
}
if (goog.dom.tags.isVoidTag(tagName.toLowerCase())) {
goog.asserts.assert(!content.length,
'Void tag <' + tagName + '> does not allow content.');
result += '>';
} else {
var html = goog.html.SafeHtml.concat(content);
result += '>' + goog.html.SafeHtml.unwrap(html) + '</' + tagName + '>';
dir = html.getDirection();
}
var dirAttribute = opt_attributes && opt_attributes['dir'];
if (dirAttribute) {
if (/^(ltr|rtl|auto)$/i.test(dirAttribute)) {
// If the tag has the "dir" attribute specified then its direction is
// neutral because it can be safely used in any context.
dir = goog.i18n.bidi.Dir.NEUTRAL;
} else {
dir = null;
}
}
return goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
result, dir);
};
/**
* @param {!Object<string, string>} fixedAttributes
* @param {!Object<string, string>} defaultAttributes
* @param {!Object<string, goog.html.SafeHtml.AttributeValue_>=}
* opt_attributes Optional attributes passed to create*().
* @return {!Object<string, goog.html.SafeHtml.AttributeValue_>}
* @throws {Error} If opt_attributes contains an attribute with the same name
* as an attribute in fixedAttributes.
* @package
*/
goog.html.SafeHtml.combineAttributes = function(
fixedAttributes, defaultAttributes, opt_attributes) {
var combinedAttributes = {};
var name;
for (name in fixedAttributes) {
goog.asserts.assert(name.toLowerCase() == name, 'Must be lower case');
combinedAttributes[name] = fixedAttributes[name];
}
for (name in defaultAttributes) {
goog.asserts.assert(name.toLowerCase() == name, 'Must be lower case');
combinedAttributes[name] = defaultAttributes[name];
}
for (name in opt_attributes) {
var nameLower = name.toLowerCase();
if (nameLower in fixedAttributes) {
throw Error('Cannot override "' + nameLower + '" attribute, got "' +
name + '" with value "' + opt_attributes[name] + '"');
}
if (nameLower in defaultAttributes) {
delete combinedAttributes[nameLower];
}
combinedAttributes[name] = opt_attributes[name];
}
return combinedAttributes;
};
/**
* A SafeHtml instance corresponding to the HTML doctype: "<!DOCTYPE html>".
* @const {!goog.html.SafeHtml}
*/
goog.html.SafeHtml.DOCTYPE_HTML =
goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
'<!DOCTYPE html>', goog.i18n.bidi.Dir.NEUTRAL);
/**
* A SafeHtml instance corresponding to the empty string.
* @const {!goog.html.SafeHtml}
*/
goog.html.SafeHtml.EMPTY =
goog.html.SafeHtml.createSafeHtmlSecurityPrivateDoNotAccessOrElse(
'', goog.i18n.bidi.Dir.NEUTRAL);