I have a GatsbyJS site that I am working on where the main content source is a Wordpress install. One of the things I like to add to my sites is the ability to have placeholder areas in the site where I can control the content via the CMS. Usually I have a header_scripts area that goes at the bottom of the <head> tag, a body_scripts area that goes at the start of the <body> tag, and a footer_scripts area that goes at the bottom of the page <body>. With these three, I can usually integrate third-party add-ins pretty easily without having to do code deployments.
Sometimes I need to embed stylesheets, sometimes I need to embed script tags, and sometimes I need to throw in <meta> tags. Really the content could be anything. This data comes back as a raw string from my Wordpress GraphQL endpoint.
So now my question is, how do I get this content injected into my Gatsby site in the following places:
<html>
<head>
...
{header_scripts}
</head>
<body>
{body_scripts}
...
{footer_scripts}
</body>
</html>
I've found so far that I can just include the body_scripts and footer_scripts in a fairly regular manner in my Gatsby page template. In gatsby-node.js, I pass in the property values using the pageContext. It's kind of a bummer that they need to be wrapped in a <div /> tag, but they seem to work just fine.
import React from 'react'
export default class PageTemplate extends React.Component {
render = () => {
return (
<React.Fragment>
{this.props.pageContext.bodyScripts && (
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.bodyScripts}} />
)}
{/* my page content here */}
{this.props.pageContext.footerScripts && (
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.footerScripts}} />
)}
</React.Fragment>
)
}
}
Now for the real question. I am stumped on how to get the dynamic content from the header_scripts into the Gatsby server-side-rendering <head> tag. The closest thing I have found to being able to inject content into the head is to leverage the gatsby-ssr.js onRenderBody function. However, this seems to require pre-determined React component instances in order to function. I can't just pass it in plain raw string content and see the output in the page source:
export const onRenderBody = async ({
pathname,
setHeadComponents,
setHtmlAttributes,
setBodyAttributes,
setPreBodyComponents,
setPostBodyComponents,
setBodyProps
}, pluginOptions) => {
setHeadComponents(['<script>alert("hello");</script>'])
}
This results in an escaped string getting inserted into the <head> tag:
<html>
<head>
...
<script>alert("hello");</script>
</head>
<body>
...
</body>
</html>
I'm at a loss as to how to proceed. I can't just wrap my string in a <div /> tag like in the body because div tags can't go inside the head tag. I can't think of any head-capable HTML tags that would accept this kind of content.
The only idea I've had is to actually parse the string content into full React components. This seems daunting given the number of possible tags & formatting that I would need to support.
Am I going about this the wrong way? How can I get my arbitrary content into my Gatsby site's head tag?
It's a broad question and it will need some trials and errors to ensure that it's fully working without caveats in all scenarios but, among the things you've tried, you can add a few more options to the list to check which ones fit better.
Regarding the body_scripts and footer_scripts both can be inserted using the:
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.footerScripts}} />
In any desired page or template. For the header_scripts and the meta tags (SEO), you can use the <Helmet> component. Basically, using this component, everything that is wrapped inside, it's becomes transpiled inside the <head> tag once compiled.
export default class PageTemplate extends React.Component {
render = () => {
return (
<React.Fragment>
<Helmet>
{this.props.pageContext.headerScripts && (
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.headScripts}} />
)}
</Helmet>
{this.props.pageContext.bodyScripts && (
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.bodyScripts}} />
)}
{/* my page content here */}
{this.props.pageContext.footerScripts && (
<div dangerouslySetInnerHTML={{__html:this.props.pageContext.footerScripts}} />
)}
</React.Fragment>
)
}
}
However, if the data comes from a CMS, it won't be available in the SSR yet, so, one easy thing you can do is to customize the outputted HTML (html.js) that Gatsby generates in each compilation. From the docs:
Customizing html.js is a workaround solution for when the use of the
appropriate APIs is not available in gatsby-ssr.js. Consider using
onRenderBody or onPreRenderHTML instead of the method above. As a
further consideration, customizing html.js is not supported within a
Gatsby Theme. Use the API methods mentioned instead.
Run:
cp .cache/default-html.js src/html.js
Or manually, copy the .cache/default-html.js file and paste it /src folder. There you can customize the final HTML.
Related
I am trying to embed a public FB post into the main page of my application. I am following FB guide and it's pretty simple. It works when I do it in .html file, but doesn't with Next JS.
Basically, instructions are that you need to insert this right after the body opening tag
<div id="fb-root"></div>
<script async defer crossorigin="anonymous"
src="https://connect.facebook.net/en_US/sdk.js#xfbml=1&autoLogAppEvents=1&version=v9.0&appId={appId}" nonce={someNonce}"></script>
and then you put the other part wherever you want.
I even created a custom _document.js file and included this script, I can also see it in the browser. But the post does not get loaded.
Anyone had this kind of issue?
Assuming you already have the JS SDK loaded in your document, like you mentioned (you might also load the script on-demand via JavaScript if preferred).
// pages/_document
class MyDocument extends Document {
render() {
return (
<Html lang="en">
<!-- additional code -->
<body>
<!-- additional code -->
<script
async
defer
src="https://connect.facebook.net/en_US/sdk.js#xfbml=1&version=v3.2"
/>
</body>
</Html>
);
}
}
You can then render a Facebook post inside one of your components with:
<div
className="fb-post"
data-href="https://www.facebook.com/20531316728/posts/10154009990506729/"
/>
For further details refer to the official Embedded Posts documentation.
I have a simple React site up and when I go to "View Source" in Chrome, It doesnt show much of the markup.Mostly JS imports. But if I click on an element with Dev tools up, it shows me the html as I would normally see it.
Can someone explain this to me?
Thanks
View source will have the the content what you have in build/index.html or public/index.html
index.html will have some <script> tags. Browser executes these JavaScript files in script tag and renders the page. We can say this as dynamic code or runtime generated html, css and other code.
So View Source will show only static contents, that is what you have in index.html. Its same as if you open index.html in any editor like notepad.
Where as when using dev tools you will see all runtime generated code. That is what dev tools indend to do.
And if you need to see the React components, state, props and other details, you need to use React dev tools for chrome
A simple example would be:
index.html
<html>
<body>
<div id="app"></div>
<script>
document.getElementById("app").innerHTML = "Hello World";
</script>
</body>
</html>
You will see the above code in View Source.
You will see below code in dev tools
<html>
<body>
<div id="app">Hello World</div>
<script>
document.getElementById("app").innerHTML = "Hello World";
</script>
</body>
</html>
Hope this is clear.
The actual source is mostly JS, between libraries that react uses, libraries you've imported, and the JS you've written.
When you write a view, typically in .jsx format, it is JS that is translated into HTML. So after the dom has populated by using the combination of the libraries and what you have written it is then available to view the html in the DOM, but the source will still only display the JS.
Sudo example
example.jsx
...
render() {
const example = ['a', 'b', 'c'];
return ( <div> { example.map((val) => (<p>{val}</p>)) } </div> }
}
...
Source
...
require('example.js')
...
DOM
...
<div>
<p>a</p>
<p>b</p>
<p>c</p>
</div>
...
Just wondering what the procedure is loading an external script into a component which renders HTML?
I call a script, which returns me an unordered list which i want to use for an image carousel it looks something like this but currently isn't working
this is what i have inside my render
return(
<Slick {...settings}>
<script
type="text/javascript"
src="https://some.external.script.js"
/>
<div
class="render-html-here-from-script"
/>
<script>
SomeScript.require(['xxx'], function(arg)
{arg.loadAll().done(function(embed) {
// code here gets list and binds above in div
})}
)
</script>
</Slick>
)
the above code works fine if I just copy/paste straight into a standard HTML page
Thanks
I am using a headless CMS(Strapi) and React on the frontend. I would like to render code blocks with highlighting using PrismJS (or anything).
In my render():
<div>
<pre>
<code className="language-css">{`p { color: red }`}</code>
</pre>
<h2>{this.state.title}</h2>
<div dangerouslySetInnerHTML={{ __html: `${content}` }} />
</div>
The code wrapped with <pre> tags serves as an example of what I'm trying to do.
The problem is that since I'm using the Strapi CMS, the code block not recognized by PrismJS. Here's how it's rendered:
The top part is the code directly written in my component while the bottom is returned from the CMS. In the WYSIWYG of the CMS I have the following <pre><code class="language-css">p { color: red }</code></pre>
Is there a way that I can write content with text and code and have the code highlighted properly?
This seems like a similar issue: React : Rendering a syntax highlighted code block
This solved my problem: https://github.com/akiran/react-highlight
Be sure to set your CSS in index.html and I added the following in my project:
<Highlight language="javascript" innerHTML={true}>
{content}
</Highlight>
Works perfectly! Hope this helps someone.
I need create a component to render like this:
<div class="row">
<div class="col">
<div class="some another class">
<h3>{{title}}</title>
</div>
</div>
<div class="col">
<p>{{contentA}}</p>
</div>
<div class="row">
<div class="some wrapper">
<p>{{contentB}}</p>
<div>
</div>
<div>
It will receive the following data:
title - a string
contentA - a large string (paragraph), may contain
links (a href)
contentB - a large string or a complex HTML code
Here are the following methods I found. However, I'm not sure about which one is the recommended way by React.
Method 1
<Component title="a" contentA="some large content" contentB="another large content"/>
Pros: Easy to access different props in different sections of the component
Cons: Too complex to handle if the content as large HTML content
Method 2
<Component>
<title>a</title
<content>some large content</content>
<content>another large content</content>
</Component>
Pros: Much simpler code
Cons: Need to filter props.children and find each element to put in correct place in the component
This is not really an accurate statement:
Cons: Too complex to handle if the content as HTML contents
If a value can be held in a variable as a string, it can be used as an argument passed into your component. If you don't want to be bothered trying to escape the quotes inside your prop values, I would encourage you to ditch the <Component attr="someValue"/> syntax and instead use <Component attr={'someValue'}/>. This allows you to pass variables into your props. This also allows you to use template literals to pass values, like so:
<Component
title="a"
contentA={`
<html>
<head></head>
<body>
<p>Here is my super-big</p>
<p>HTML-infused content</p>
<p>I can even inject ${variables} in here!</p>
</body>
</html>
`}
contentB="another large content"
/>
If you feel like that starts to clutter-up the declaration of your component, you can instead set those values in a variable and then pass them very cleanly into the component, as such:
render() {
const bigHtmlContent = (
<html>
<head></head>
<body>
<p>Here is my super-big</p>
<p>HTML-infused content</p>
<p>I can even inject {variables} in here!</p>
</body>
</html>
);
return (
<Component
title="a"
contentA={bigHtmlContent}
contentB="another large content"
/>
);
}
Of course, you can move the definition out of the render() function altogether if that suits you better:
getBigHtmlContent() {
return (
<html>
<head></head>
<body>
<p>Here is my super-big</p>
<p>HTML-infused content</p>
<p>I can even inject {variables} in here!</p>
</body>
</html>
);
}
render() {
return (
<Component
title="a"
contentA={() => this.getBigHtmlContent()}
contentB="another large content"
/>
);
}
When I'm creating components, I tend to pass everything as props (as shown in the examples above). I only use children if I'm creating a higher-order component which, by design, is supposed to act as a container for certain types of children.
For example, in Material UI there is a <List> component which requires one-or-more <ListItem>s. In that case, I don't think it would make much sense to pass the <ListItems>s as props. They are (and should be) children of the <List> component.
React is all about creating granular components, the more granular you component tree is, you are doing it the more React way.
You say you get 3 things text,contentA and ContentB
Title: it's already granular.
content A: You say its a "a large string (paragraph), may container links (a href)"
, if its a paragraph it is granular but if its a collection of paragraphs, I think you should take that to a different component. Ex: ContentA component
Content B: This is clearly said that its a complex HTML code, that is what is React for, you need to break this complex HTML code into granular components which will make it more maintainable and it is a React best practice too.
have patience while breaking this into components, it's definitely worth it.
hope that helps.