module react-helmet
1. boolean react-helmet.__esModule
2. function react-helmet.Helmet ()
3. function react-helmet.default ()
4. object react-helmet.Helmet.propTypes
5. object react-helmet.Helmet.prototype
6. object react-helmet.HelmetUtils
module react-helmet.Helmet
1. function react-helmet.Helmet ()
2. function react-helmet.Helmet.peek ()
3. function react-helmet.Helmet.renderStatic ()
4. function react-helmet.Helmet.rewind ()
5. object react-helmet.Helmet.defaultProps
6. object react-helmet.Helmet.propTypes
module react-helmet.Helmet.propTypes
module react-helmet.Helmet.prototype
module react-helmet.HelmetUtils

module react-helmet

function react-helmet.Helmet ()

description and source-code

function HelmetWrapper() {
    _classCallCheck(this, HelmetWrapper);

    return _possibleConstructorReturn(this, _React$Component.apply(this, arguments));
}

example usage
```
n/a
```

function react-helmet.default ()

description and source-code

function HelmetWrapper() {
    _classCallCheck(this, HelmetWrapper);

    return _possibleConstructorReturn(this, _React$Component.apply(this, arguments));
}

example usage
```
n/a
```

module react-helmet.Helmet

function react-helmet.Helmet ()

description and source-code

function HelmetWrapper() {
    _classCallCheck(this, HelmetWrapper);

    return _possibleConstructorReturn(this, _React$Component.apply(this, arguments));
}

example usage
```
n/a
```

function react-helmet.Helmet.peek ()

description and source-code
```
function peek() {
  return state;
}
```

example usage

...
        <Helmet>
            <title>Fancy title</title>
        </Helmet>,
        container
    );

    requestIdleCallback(() => {
        expect(Helmet.peek().title).to.be.equal("Fancy title");
        Helmet.canUseDOM = false;
        expect(Helmet.peek().title).to.be.equal("Fancy title");
        Helmet.canUseDOM = true;

        done();
    });
});
...

function react-helmet.Helmet.renderStatic ()

description and source-code

renderStatic = function () {
    var mappedState = Component.rewind();
    if (!mappedState) {
        // provide fallback if mappedState is undefined
        mappedState = (0, _HelmetUtils.mapStateOnServer)({
            baseTag: [],
            bodyAttributes: {},
            encodeSpecialCharacters: true,
            htmlAttributes: {},
            linkTags: [],
            metaTags: [],
            noscriptTags: [],
            scriptTags: [],
            styleTags: [],
            title: "",
            titleAttributes: {}
        });
    }

    return mappedState;
}

example usage

...
<a name="5.0.0"></a>
# [5.0.0](https://github.com/nfl/react-helmet/compare/4.0.0...v5.0.0) (2017-03-21)

### Features

- New Simplified API (fully backward-compatible) - Helmet now takes plain HTML tags for the majority of the API with just a few
remaining props for Helmet - retaining `titleTemplate`, `defaultTitle`, `onChangeClientState`, and one new - `encodeSpecialCharacters
` - refer to README for details. Directly passing Helmet props will be deprecated in the future. [(#246)](https://github.com/nfl
/react-helmet/pull/246)
- `requestIdleCallback` utilized to consolidate DOM changes and makes these non-blocking for things like animations.  Fixes first
 client-side render not matching server-side render.  Maintains one DOM change between route changes on the client-side as well. [(#
248)](https://github.com/nfl/react-helmet/pull/248)
- On server-side, `Helmet.renderStatic()` aliased to `Helmet.rewind()` for more clarity
. `rewind` will be deprecated in the future.
- Yarn support

# 4.0.0

### Features

- Replacing PlainComponent with stateless functional component `NullComponent`, with a hard requirement to use React 15 or higher
.
...

function react-helmet.Helmet.rewind ()

description and source-code

rewind = function () {
    var mappedState = Component.rewind();
    if (!mappedState) {
        // provide fallback if mappedState is undefined
        mappedState = (0, _HelmetUtils.mapStateOnServer)({
            baseTag: [],
            bodyAttributes: {},
            encodeSpecialCharacters: true,
            htmlAttributes: {},
            linkTags: [],
            metaTags: [],
            noscriptTags: [],
            scriptTags: [],
            styleTags: [],
            title: "",
            titleAttributes: {}
        });
    }

    return mappedState;
}

example usage

...
<a name="5.0.0"></a>
# [5.0.0](https://github.com/nfl/react-helmet/compare/4.0.0...v5.0.0) (2017-03-21)

### Features

- New Simplified API (fully backward-compatible) - Helmet now takes plain HTML tags for the majority of the API with just a few
remaining props for Helmet - retaining `titleTemplate`, `defaultTitle`, `onChangeClientState`, and one new - `encodeSpecialCharacters
` - refer to README for details. Directly passing Helmet props will be deprecated in the future. [(#246)](https://github.com/nfl
/react-helmet/pull/246)
- `requestIdleCallback` utilized to consolidate DOM changes and makes these non-blocking for things like animations.  Fixes first
 client-side render not matching server-side render.  Maintains one DOM change between route changes on the client-side as well. [(#
248)](https://github.com/nfl/react-helmet/pull/248)
- On server-side, `Helmet.renderStatic()` aliased to `Helmet.rewind()` for more clarity
. `rewind` will be deprecated in the future.
- Yarn support

# 4.0.0

### Features

- Replacing PlainComponent with stateless functional component `NullComponent`, with a hard requirement to use React 15 or higher
.
...

module react-helmet.Helmet.propTypes

function react-helmet.Helmet.propTypes.base ()

description and source-code
```
base = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.bodyAttributes ()

description and source-code

bodyAttributes = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.children ()

description and source-code

children = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.defaultTitle ()

description and source-code

defaultTitle = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.encodeSpecialCharacters ()

description and source-code

encodeSpecialCharacters = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.htmlAttributes ()

description and source-code

htmlAttributes = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.link ()

description and source-code
```
link = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.meta ()

description and source-code
```
meta = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.noscript ()

description and source-code

noscript = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.onChangeClientState ()

description and source-code

onChangeClientState = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.script ()

description and source-code
```
script = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.style ()

description and source-code
```
style = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.title ()

description and source-code
```
title = function () { [native code] }
```
example usage
```
n/a
```

function react-helmet.Helmet.propTypes.titleAttributes ()

description and source-code

titleAttributes = function () { [native code] }

example usage
```
n/a
```

function react-helmet.Helmet.propTypes.titleTemplate ()

description and source-code

titleTemplate = function () { [native code] }

example usage
```
n/a
```

module react-helmet.Helmet.prototype

function react-helmet.Helmet.prototype.flattenArrayTypeChildren (_ref)

description and source-code

function flattenArrayTypeChildren(_ref) {
    var _extends2;

    var child = _ref.child,
        arrayTypeChildren = _ref.arrayTypeChildren,
        newChildProps = _ref.newChildProps,
        nestedChildren = _ref.nestedChildren;

    return _extends({}, arrayTypeChildren, (_extends2 = {}, _extends2[child.type] = [].concat(arrayTypeChildren[child.type] || [], [
_extends({}, newChildProps, this.mapNestedChildrenToProps(child, nestedChildren))]), _extends2));
}

example usage

...

                switch (child.type) {
case TAG_NAMES.LINK:
case TAG_NAMES.META:
case TAG_NAMES.NOSCRIPT:
case TAG_NAMES.SCRIPT:
case TAG_NAMES.STYLE:
    arrayTypeChildren = _this2.flattenArrayTypeChildren({
        child: child,
        arrayTypeChildren: arrayTypeChildren,
        newChildProps: newChildProps,
        nestedChildren: nestedChildren
    });
    break;
...

function react-helmet.Helmet.prototype.mapArrayTypeChildrenToProps (arrayTypeChildren, newProps)

description and source-code

function mapArrayTypeChildrenToProps(arrayTypeChildren, newProps) {
    var newFlattenedProps = _extends({}, newProps);

    Object.keys(arrayTypeChildren).forEach(function (arrayChildName) {
        var _extends5;

        newFlattenedProps = _extends({}, newFlattenedProps, (_extends5 = {}, _extends5[arrayChildName] = arrayTypeChildren[arrayChildName
], _extends5));
    });

    return newFlattenedProps;
}

example usage

...
                    newChildProps: newChildProps,
                    nestedChildren: nestedChildren
                });
                break;
        }
    });

    newProps = this.mapArrayTypeChildrenToProps(arrayTypeChildren, newProps);
    return newProps;
};

HelmetWrapper.prototype.render = function render() {
    var _props = this.props,
        children = _props.children,
        props = _objectWithoutProperties(_props, ["children"]);
...

function react-helmet.Helmet.prototype.mapChildrenToProps (children, newProps)

description and source-code

function mapChildrenToProps(children, newProps) {
    var _this2 = this;

    var arrayTypeChildren = {};

    _react2.default.Children.forEach(children, function (child) {
        if (!child || !child.props) {
            return;
        }

        var _child$props = child.props,
            nestedChildren = _child$props.children,
            childProps = _objectWithoutProperties(_child$props, ["children"]);

        var newChildProps = (0, _HelmetUtils.convertReactPropstoHtmlAttributes)(childProps);

        _this2.warnOnInvalidChildren(child, nestedChildren);

        switch (child.type) {
            case _HelmetConstants.TAG_NAMES.LINK:
            case _HelmetConstants.TAG_NAMES.META:
            case _HelmetConstants.TAG_NAMES.NOSCRIPT:
            case _HelmetConstants.TAG_NAMES.SCRIPT:
            case _HelmetConstants.TAG_NAMES.STYLE:
                arrayTypeChildren = _this2.flattenArrayTypeChildren({
                    child: child,
                    arrayTypeChildren: arrayTypeChildren,
                    newChildProps: newChildProps,
                    nestedChildren: nestedChildren
                });
                break;

            default:
                newProps = _this2.mapObjectTypeChildren({
                    child: child,
                    newProps: newProps,
                    newChildProps: newChildProps,
                    nestedChildren: nestedChildren
                });
                break;
        }
    });

    newProps = this.mapArrayTypeChildrenToProps(arrayTypeChildren, newProps);
    return newProps;
}

example usage

...
    var _props = this.props,
        children = _props.children,
        props = _objectWithoutProperties(_props, ["children"]);

    var newProps = _extends({}, props);

    if (children) {
        newProps = this.mapChildrenToProps(children, newProps);
    }

    return React.createElement(Component, newProps);
};

_createClass(HelmetWrapper, null, [{
    key: "canUseDOM",
...

function react-helmet.Helmet.prototype.mapNestedChildrenToProps (child, nestedChildren)

description and source-code

function mapNestedChildrenToProps(child, nestedChildren) {
    if (!nestedChildren) {
        return null;
    }

    switch (child.type) {
        case _HelmetConstants.TAG_NAMES.SCRIPT:
        case _HelmetConstants.TAG_NAMES.NOSCRIPT:
            return {
                innerHTML: nestedChildren
            };

        case _HelmetConstants.TAG_NAMES.STYLE:
            return {
                cssText: nestedChildren
            };
    }

    throw new Error("<" + child.type + " /> elements are self-closing and can not contain children. Refer to our API for more information
.");
}

example usage

...
var _extends2;

var child = _ref.child,
    arrayTypeChildren = _ref.arrayTypeChildren,
    newChildProps = _ref.newChildProps,
    nestedChildren = _ref.nestedChildren;

return _extends({}, arrayTypeChildren, (_extends2 = {}, _extends2[child.type] = [].concat(arrayTypeChildren[child.type] || [], [
_extends({}, newChildProps, this.mapNestedChildrenToProps(child, nestedChildren))]),
_extends2));
        };

        HelmetWrapper.prototype.mapObjectTypeChildren = function mapObjectTypeChildren(_ref2) {
var _extends3, _extends4;

var child = _ref2.child,
    newProps = _ref2.newProps,
...

function react-helmet.Helmet.prototype.mapObjectTypeChildren (_ref2)

description and source-code

function mapObjectTypeChildren(_ref2) {
    var _extends3, _extends4;

    var child = _ref2.child,
        newProps = _ref2.newProps,
        newChildProps = _ref2.newChildProps,
        nestedChildren = _ref2.nestedChildren;

    switch (child.type) {
        case _HelmetConstants.TAG_NAMES.TITLE:
            return _extends({}, newProps, (_extends3 = {}, _extends3[child.type] = nestedChildren, _extends3.titleAttributes = _extends
({}, newChildProps), _extends3));

        case _HelmetConstants.TAG_NAMES.BODY:
            return _extends({}, newProps, {
                bodyAttributes: _extends({}, newChildProps)
            });

        case _HelmetConstants.TAG_NAMES.HTML:
            return _extends({}, newProps, {
                htmlAttributes: _extends({}, newChildProps)
            });
    }

    return _extends({}, newProps, (_extends4 = {}, _extends4[child.type] = _extends({}, newChildProps), _extends4));
}

example usage

...
            arrayTypeChildren: arrayTypeChildren,
            newChildProps: newChildProps,
            nestedChildren: nestedChildren
        });
        break;

    default:
        newProps = _this2.mapObjectTypeChildren({
            child: child,
            newProps: newProps,
            newChildProps: newChildProps,
            nestedChildren: nestedChildren
        });
        break;
}
...

function react-helmet.Helmet.prototype.render ()

description and source-code

function render() {
    var _props = this.props,
        children = _props.children,
        props = _objectWithoutProperties(_props, ["children"]);

    var newProps = _extends({}, props);

    if (children) {
        newProps = this.mapChildrenToProps(children, newProps);
    }

    return _react2.default.createElement(Component, newProps);
}

example usage

...
afterEach(() => {
    ReactDOM.unmountComponentAtNode(container);
});

describe("api", () => {
    describe("title", () => {
        it("updates page title", (done) => {
            ReactDOM.render(
                <Helmet
                    defaultTitle={"Fallback"}
                >
                    <title>Test Title</title>
                </Helmet>,
                container
            );
...

function react-helmet.Helmet.prototype.shouldComponentUpdate (nextProps)

description and source-code

function shouldComponentUpdate(nextProps) {
    return !(0, _deepEqual2.default)(this.props, nextProps);
}

example usage
```
n/a
```

function react-helmet.Helmet.prototype.warnOnInvalidChildren (child, nestedChildren)

description and source-code

function warnOnInvalidChildren(child, nestedChildren) {
    if (process.env.NODE_ENV !== "production") {
        if (!_HelmetConstants.VALID_TAG_NAMES.some(function (name) {
            return child.type === name;
        })) {
            if (typeof child.type === "function") {
                return (0, _HelmetUtils.warn)("You may be attempting to nest <Helmet> components within each other, which is not
 allowed. Refer to our API for more information.");
            }

            return (0, _HelmetUtils.warn)("Only elements types " + _HelmetConstants.VALID_TAG_NAMES.join(", ") + " are allowed.
Helmet does not support rendering <" + child.type + "> elements. Refer to our API for more information.");
        }

        if (nestedChildren && typeof nestedChildren !== "string") {
            throw new Error("Helmet expects a string as a child of <" + child.type + ">. Did you forget to wrap your children in
 braces? ( <" + child.type + ">{``}</" + child.type + "> ) Refer to our API for more information.");
        }
    }

    return true;
}

example usage

...

var _child$props = child.props,
    nestedChildren = _child$props.children,
    childProps = _objectWithoutProperties(_child$props, ["children"]);

var newChildProps = convertReactPropstoHtmlAttributes(childProps);

_this2.warnOnInvalidChildren(child, nestedChildren);

switch (child.type) {
    case TAG_NAMES.LINK:
    case TAG_NAMES.META:
    case TAG_NAMES.NOSCRIPT:
    case TAG_NAMES.SCRIPT:
    case TAG_NAMES.STYLE:
...

module react-helmet.HelmetUtils

function react-helmet.HelmetUtils.convertReactPropstoHtmlAttributes (props)

description and source-code

function convertReactPropstoHtmlAttributes(props) {
    var initAttributes = arguments.length > 1 && arguments[1] !== undefined ? arguments[1] : {};

    return Object.keys(props).reduce(function (obj, key) {
        obj[_HelmetConstants.HTML_TAG_MAP[key] || key] = props[key];
        return obj;
    }, initAttributes);
}

example usage
```
n/a
```

function react-helmet.HelmetUtils.handleClientStateChange (newState)

description and source-code

function handleClientStateChange(newState) {
    var baseTag = newState.baseTag,
        bodyAttributes = newState.bodyAttributes,
        htmlAttributes = newState.htmlAttributes,
        linkTags = newState.linkTags,
        metaTags = newState.metaTags,
        noscriptTags = newState.noscriptTags,
        onChangeClientState = newState.onChangeClientState,
        scriptTags = newState.scriptTags,
        styleTags = newState.styleTags,
        title = newState.title,
        titleAttributes = newState.titleAttributes;


    if (_helmetIdleCallback) {
        cancelIdleCallback(_helmetIdleCallback);
    }

    _helmetIdleCallback = requestIdleCallback(function () {
        updateAttributes(_HelmetConstants.TAG_NAMES.BODY, bodyAttributes);
        updateAttributes(_HelmetConstants.TAG_NAMES.HTML, htmlAttributes);

        updateTitle(title, titleAttributes);

        var tagUpdates = {
            baseTag: updateTags(_HelmetConstants.TAG_NAMES.BASE, baseTag),
            linkTags: updateTags(_HelmetConstants.TAG_NAMES.LINK, linkTags),
            metaTags: updateTags(_HelmetConstants.TAG_NAMES.META, metaTags),
            noscriptTags: updateTags(_HelmetConstants.TAG_NAMES.NOSCRIPT, noscriptTags),
            scriptTags: updateTags(_HelmetConstants.TAG_NAMES.SCRIPT, scriptTags),
            styleTags: updateTags(_HelmetConstants.TAG_NAMES.STYLE, styleTags)
        };

        var addedTags = {};
        var removedTags = {};

        Object.keys(tagUpdates).forEach(function (tagType) {
            var _tagUpdates$tagType = tagUpdates[tagType],
                newTags = _tagUpdates$tagType.newTags,
                oldTags = _tagUpdates$tagType.oldTags;


            if (newTags.length) {
                addedTags[tagType] = newTags;
            }
            if (oldTags.length) {
                removedTags[tagType] = tagUpdates[tagType].oldTags;
            }
        });

        _helmetIdleCallback = null;
        onChangeClientState(newState, addedTags, removedTags);
    });
}

example usage
```
n/a
```

function react-helmet.HelmetUtils.mapStateOnServer (_ref)

description and source-code

function mapStateOnServer(_ref) {
    var baseTag = _ref.baseTag,
        bodyAttributes = _ref.bodyAttributes,
        encode = _ref.encode,
        htmlAttributes = _ref.htmlAttributes,
        linkTags = _ref.linkTags,
        metaTags = _ref.metaTags,
        noscriptTags = _ref.noscriptTags,
        scriptTags = _ref.scriptTags,
        styleTags = _ref.styleTags,
        _ref$title = _ref.title,
        title = _ref$title === undefined ? "" : _ref$title,
        titleAttributes = _ref.titleAttributes;
    return {
        base: getMethodsForTag(_HelmetConstants.TAG_NAMES.BASE, baseTag, encode),
        bodyAttributes: getMethodsForTag(_HelmetConstants.ATTRIBUTE_NAMES.BODY, bodyAttributes, encode),
        htmlAttributes: getMethodsForTag(_HelmetConstants.ATTRIBUTE_NAMES.HTML, htmlAttributes, encode),
        link: getMethodsForTag(_HelmetConstants.TAG_NAMES.LINK, linkTags, encode),
        meta: getMethodsForTag(_HelmetConstants.TAG_NAMES.META, metaTags, encode),
        noscript: getMethodsForTag(_HelmetConstants.TAG_NAMES.NOSCRIPT, noscriptTags, encode),
        script: getMethodsForTag(_HelmetConstants.TAG_NAMES.SCRIPT, scriptTags, encode),
        style: getMethodsForTag(_HelmetConstants.TAG_NAMES.STYLE, styleTags, encode),
        title: getMethodsForTag(_HelmetConstants.TAG_NAMES.TITLE, { title: title, titleAttributes: titleAttributes }, encode)
    };
}

example usage
```
n/a
```

function react-helmet.HelmetUtils.reducePropsToState (propsList)

description and source-code

function reducePropsToState(propsList) {
    return {
        baseTag: getBaseTagFromPropsList([_HelmetConstants.TAG_PROPERTIES.HREF], propsList),
        bodyAttributes: getAttributesFromPropsList(_HelmetConstants.ATTRIBUTE_NAMES.BODY, propsList),
        encode: getInnermostProperty(propsList, _HelmetConstants.HELMET_PROPS.ENCODE_SPECIAL_CHARACTERS),
        htmlAttributes: getAttributesFromPropsList(_HelmetConstants.ATTRIBUTE_NAMES.HTML, propsList),
        linkTags: getTagsFromPropsList(_HelmetConstants.TAG_NAMES.LINK, [_HelmetConstants.TAG_PROPERTIES.REL, _HelmetConstants.TAG_PROPERTIES
.HREF], propsList),
        metaTags: getTagsFromPropsList(_HelmetConstants.TAG_NAMES.META, [_HelmetConstants.TAG_PROPERTIES.NAME, _HelmetConstants.
TAG_PROPERTIES.CHARSET, _HelmetConstants.TAG_PROPERTIES.HTTPEQUIV, _HelmetConstants.TAG_PROPERTIES.PROPERTY, _HelmetConstants.TAG_PROPERTIES
.ITEM_PROP], propsList),
        noscriptTags: getTagsFromPropsList(_HelmetConstants.TAG_NAMES.NOSCRIPT, [_HelmetConstants.TAG_PROPERTIES.INNER_HTML], propsList
),
        onChangeClientState: getOnChangeClientState(propsList),
        scriptTags: getTagsFromPropsList(_HelmetConstants.TAG_NAMES.SCRIPT, [_HelmetConstants.TAG_PROPERTIES.SRC, _HelmetConstants
.TAG_PROPERTIES.INNER_HTML], propsList),
        styleTags: getTagsFromPropsList(_HelmetConstants.TAG_NAMES.STYLE, [_HelmetConstants.TAG_PROPERTIES.CSS_TEXT], propsList),
        title: getTitleFromPropsList(propsList),
        titleAttributes: getAttributesFromPropsList(_HelmetConstants.ATTRIBUTE_NAMES.TITLE, propsList)
    };
}

example usage
```
n/a
```

function react-helmet.HelmetUtils.requestIdleCallback (cb)

description and source-code

requestIdleCallback = function (cb) {
    var start = Date.now();
    return setTimeout(function () {
        cb({
            didTimeout: false,
            timeRemaining: function timeRemaining() {
                return Math.max(0, 50 - (Date.now() - start));
            }
        });
    }, 1);
}

example usage
```
n/a
```

function react-helmet.HelmetUtils.warn (msg)

description and source-code

function warn(msg) {
    return console && typeof console.warn === "function" && console.warn(msg);
}

example usage

...

return function (id) {
    return clearTimeout(id);
};
}();

var warn = function warn(msg) {
return console && typeof console.warn === "function" && console.warn(msg);
};

var _helmetIdleCallback = null;

var handleClientStateChange = function handleClientStateChange(newState) {
var baseTag = newState.baseTag,
    bodyAttributes = newState.bodyAttributes,
...

api documentation for react-helmet (v5.0.3)

A document head manager for React

table of contents