@frontity/html2react
API reference of `@frontity/html2react` package
This package is in charge of converting HTML to React. It works with processors that match HTML portions and replaces them with React components.
Add the
html2react
package to your project:npm i @frontity/html2react
This package needs to be included in your
frontity.settings.js
file as one of the packages that will be part of the Frontity project:frontity.settings.js
module.exports = {
packages: ["@frontity/html2react"],
};
If you use an already created theme this package will already be configured so you don't need to do anything else.
If you're creating a custom theme you'll have to define the processors you want to use in the configuration of the package.
This is how you need to include the Component that will render the parsed content. The only prop it takes is
html
, and you'll usually pass post.content.rendered
to it:import React from "react";
const Post = ({ state, libraries }) => {
const data = state.source.get(state.router.link);
const post = state.source[data.type][data.id];
// Component exposed by html2react.
const Html2React = libraries.html2react.Component;
return (
<div>
<Title />
<AuthorAndDate />
<FeaturedImage />
{/* Use Html2React to render the post HTML content */}
<Html2React html={post.content.rendered} />
</div>
);
};
Processors are the blocks of logic used by
html2react
to detect specific portions of HTML and return custom HTML or React components.The
processors
field is an array where you can push all the processors you want to use with html2react
. You can check the default processors here.You can add your processors directly in
libraries.html2react.processors
. Here you can see as an example how this is done in mars-theme
:import image from "@frontity/html2react/processors/image";
import customProcessor from "./processors/custom";
const myPackage = {
roots: { ... },
state: { ... },
actions: { ... },
libraries: {
html2react: {
processors: [image, customProcessor]
}
}
};
export default myPackage;
A processor is an object with four properties:
name
, priority
, test
,and processor
.Name | Type | Required | Description |
name | string | yes | the name of your processor |
priority | number | yes | A number that lets the package know in which order processors should be evaluated. The processors are evaluated in numeric order. For example, a processor with priority of 10 will be applied before a processor with a priority of 20 |
test | function | yes | A function that evaluate each node, and if it returns true , this node will be passed down to the processor function |
processor | function | yes | A function to apply some logic to the node that we want to modify. It could be substituting HTML tags for React component with some logic, as adding lazy-loading to images, or just modifying some attributes, like adding target="_blank" to the links. |
Both the
test
and the processor
functions receive the same arguments ({ node, root, state, libraries })
Name | Type | Description |
node | object | The HTML node tag the processor is evaluating |
root | object | The top node of the node tree |
state | object | Access to Frontity's state . This could be useful to use some parts of the state inside your processor. For example, using your state.theme.colors |
libraries | object | Access to Frontity's libraries . As it happens with the state , sometimes could be useful to access your libraries as well |
The
test
function returns a boolean to indicate processor
function should be executed (the node matches the pattern).The
processor
function returns a node
object.This is how the
image
processor is implemented in html2react
:import Image from "@frontity/components/image";
const image = {
// We can add a name to identify it later.
name: "image",
// We can add a priority so it executes before or after other processors.
priority: 10,
// Only process the node it if it's an image.
test: ({ node }) => node.component === "img",
processor: ({ node }) => {
// If the image is inside a <noscript> tag, we don't want to process it.
if (node.parent.component === "noscript") return null;
// Many WP lazy load plugins move the real "src" to "data-src", so we move it back.
if (node.props["data-src"]) node.props.src = node.props["data-src"];
if (node.props["data-srcset"])
node.props.srcSet = node.props["data-srcset"];
// We tell Html2React that it should use the <Image /> component
// from @frontity/components, which includes lazy loading support.
node.component = Image;
return node;
},
};
export default image;
You don't need to return a React component, you can also modify the attributes (props) of the node. For example, this processor adds
target="_blank"
to the <a>
tags with href starting with http
:const extAnchors = {
name: "external anchors",
priority: 10,
// Only process the node it if it's an anchor and href starts with http.
test: ({ node }) =>
node.component === "a" && node.props.href.startsWith("http"),
// Add the target attribute.
processor: ({ node }) => {
node.props.target = "_blank";
return node;
},
};
The object
node
received by both test
and processor
can be an Element
, a Text
or a Comment
. You can distinguish between them using node.type
.- An
Element
is an HTML tag or a React component. - A
Text
is a text content. For example, the text inside a<p>
tag. - A
Comment
is just an HTML comment. Like this<!-- comment -->
.
The common properties are:
Name | Type | Description | | |
type | string | The Node type. </br> Possible values: `"element" | "text" | "comment"` |
parent | Element | The parent of this node, which is always an element (text or comment can't have children) | | |
ignore | boolean | If you set ignore to true for a node, it won't pass any test . This is useful in some situations when you don't want additional processors applied to this node. | | |
Besides common properties,
Element
nodes are also defined by the following properties:Name | Type | Description |
component | string or function (React component) | If it's a string, it's an HTML tag and if it's a function is a React component. You can change it at will and it is what you would usually do when you want to convert HTML tags to React components |
props | object | An object containing all the HTML attributes of that node or props of that React component. You can also change them at will. All the attributes are converted to the React equivalents, even for HTML tags. |
children | array (of nodes) | An array containing other nodes, children to this one. If you want to get rid of the children, just overwrite it with null or an empty array |
Examples of
props
values (and their equivalent React props):class
->className
style
->css
srcset
->srcSet
onclick
->onClick
- ..
Besides common properties,
Text
and Comment
nodes will also have the following property:Name | Type | Description |
content | string | Content of the Node |
React doesn’t execute the code inside a
<script>
tags. For that reason, html2react doesn’t execute the script tags included in the contents.The script processor, with a priority of
20
, processes <script>
tags found in the HTML for execution. <script>
type must either be application/javascript
, text/javascript
or application/ecmascript
to pass the test of the processor.The script processor is included by default in html2react. Therefore, no extra procedure is required to use the processor.
Iframes can impact the loading time and performance of a site. The iframe processor adds lazy-loading to the
<iframe>
tags found in the HTML.Add
iframe
to the processors
array in your package index.js
file.import iframe from "@frontity/html2react/processors/iframe";
const themeName = {
name: "theme-name",
...
libraries: {
html2react: {
processors: [iframe]
}
}
}
An array of the processors that will be used by
html2react
.You can add, remove or mutate any processor from the array:
// Add a processor.
libraries.html2react.processors.push(image);
// Remove a processor.
const index = libraries.html2react.processors.findIndex(
(pr) => pr.name === "image"
);
libraries.html2react.processors.splice(index, 1);
// Change a processor priority.
const processor = libraries.html2react.processors.find(
(pr) => pr.name === "image"
);
processor.priority = 20;
The React component used to render the parsed HTML.
Props
Name | Type | Required | Description |
html | string | yes | The HTML that needs to be rendered |
import React from "react";
const Post = ({ libraries }) => {
// Get the component exposed by html2react.
const Html2React = libraries.html2react.Component;
return (
<>
{/* Use it to render the HTML. */}
<Html2React html={html} />
</>
);
};
Last modified 2yr ago