react-datocms

react-datocms

A set of components and utilities to work faster with DatoCMS in React environments. Integrates seamlessy with DatoCMS's GraphQL Content Delivery API.

• TypeScript ready;
• Compatible with IE11;
• CSS-in-JS ready;
• Compatible with any GraphQL library (Apollo, graphql-hooks, graphql-request, etc.);
• Usable both client and server side;
• Compatible with vanilla React, Next.js and pretty much any other React-based solution;

Table of Contents

• Demos
• Installation
• Live real-time updates
  • Reference
  • Usage
  • Initialization options
  • Connection status
  • Error object
  • Example
• Progressive/responsive image
  • Out-of-the-box features
  • Usage
  • Example
  • Props
    • The ResponsiveImage object
• Social share, SEO and Favicon meta tags
  • Usage
  • Example

Demos

For fully working examples take a look at our examples directory.

Live demo: https://react-datocms-example.netlify.com/

Installation

npm install react-datocms

Live real-time updates

useQuerySubscription is a React hook that you can use to implement client-side updates of the page as soon as the content changes. It uses DatoCMS's GraphQL server-sent events (SSE) protocol to receive the updated query results in real-time, and is able to reconnect in case of network failures.

Live updates are great both to get instant previews of your content while editing it inside DatoCMS, or to offer real-time updates of content to your visitors (ie. news site).

Reference

const {
  data: QueryResult | undefined,
  error: ChannelErrorData | null,
  status: ConnectionStatus,
} = useQuerySubscription(options: Options);

Usage

1. Import useQuerySubscription from react-datocms and use it inside your components
2. Important: Remember to set the enabled property, or the hook will simply return the initialData you pass!

Initialization options

prop	type	required	description	default
enabled	boolean	:x:	Whether the subscription has to be performed or not	true
query	string	:white_check_mark:	The GraphQL query to subscribe
token	string	:white_check_mark:	DatoCMS API token to use
variables	Object	:x:	GraphQL variables for the query
preview	boolean	:x:	If true, the Content Delivery API with draft content will be used	false
environment	string	:x:	The name of the DatoCMS environment where to perform the query	defaults to primary environment
initialData	Object	:x:	The initial data to use on the first render
reconnectionPeriod	number	:x:	In case of network errors, the period to wait to reconnect
fetch	a fetch-like function	:x:	The fetch function to use to perform the registration query	window.fetch
baseUrl	string	:x:	The base URL to use to perform the query	https://graphql-listen.datocms.com

Connection status

The status property represents the state of the server-sent events connection. It can be one of the following:

• connecting: the subscription channel is trying to connect
• connected: the channel is open, we're receiving live updates
• closed: the channel has been permanently closed due to a fatal error (ie. an invalid query)

Error object

prop	type	description
code	string	The code of the error (ie. INVALID_QUERY)
message	string	An human friendly message explaining the error
response	Object	The raw response returned by the endpoint, if available

Example

import React from "react";
import { useQuerySubscription } from "react-datocms";

const App: React.FC = () => {
  const { status, error, data } = useQuerySubscription({
    enabled: true,
    query: `
      query AppQuery($first: IntType) {
        allBlogPosts {
          slug
          title
        }
      }`,
    variables: { first: 10 },
    token: "YOUR_API_TOKEN",
  });

  const statusMessage = {
    connecting: "Connecting to DatoCMS...",
    connected: "Connected to DatoCMS, receiving live updates!",
    closed: "Connection closed",
  };

  return (
    <div>
      <p>Connection status: {statusMessage[status]}</p>
      {error && (
        <div>
          <h1>Error: {error.code}</h1>
          <div>{error.message}</div>
          {error.response && (
            <pre>{JSON.stringify(error.response, null, 2)}</pre>
          )}
        </div>
      )}
      {data && (
        <ul>
          {data.allBlogPosts.map((blogPost) => (
            <li key={blogPost.slug}>{blogPost.title}</li>
          ))}
        </ul>
      )}
    </div>
  );
};

Progressive/responsive image

<Image /> is a React component specially designed to work seamlessly with DatoCMS’s responsiveImage GraphQL query that optimizes image loading for your sites.

Out-of-the-box features

• Offer WebP version of images for browsers that support the format
• Generate multiple smaller images so smartphones and tablets don’t download desktop-sized images
• Efficiently lazy load images to speed initial page load and save bandwidth
• Use either blur-up or background color techniques to show a preview of the image while it loads
• Hold the image position so your page doesn’t jump while images load

Usage

1. Import Image from react-datocms and use it in place of the regular <img /> tag
2. Write a GraphQL query to your DatoCMS project using the responsiveImage query

The GraphQL query returns multiple thumbnails with optimized compression. The Image component automatically sets up the “blur-up” effect as well as lazy loading of images further down the screen.

Example

For a fully working example take a look at our examples directory.

import React from "react";
import { Image } from "react-datocms";

const Page = ({ data }) => (
  <div>
    <h1>{data.blogPost.title}</h1>
    <Image data={data.blogPost.cover.responsiveImage} />
  </div>
);

const query = gql`
  query {
    blogPost {
      title
      cover {
        responsiveImage(
          imgixParams: { fit: crop, w: 300, h: 300, auto: format }
        ) {
          # HTML5 src/srcset/sizes attributes
          srcSet
          webpSrcSet
          sizes
          src

          # size information (post-transformations)
          width
          height
          aspectRatio

          # SEO attributes
          alt
          title

          # background color placeholder or...
          bgColor

          # blur-up placeholder, JPEG format, base64-encoded
          base64
        }
      }
    }
  }
`;

export default withQuery(query)(Page);

Props

prop	type	required	description	default
data	ResponsiveImage object	:white_check_mark:	The actual response you get from a DatoCMS responsiveImage GraphQL query.
className	string	:x:	Additional CSS className for root node	null
style	CSS properties	:x:	Additional CSS rules to add to the root node	null
pictureClassName	string	:x:	Additional CSS class for the inner <picture /> tag	null
pictureStyle	CSS properties	:x:	Additional CSS rules to add to the inner <picture /> tag	null
fadeInDuration	integer	:x:	Duration (in ms) of the fade-in transition effect upoad image loading	500
intersectionTreshold	float	:x:	Indicate at what percentage of the placeholder visibility the loading of the image should be triggered. A value of 0 means that as soon as even one pixel is visible, the callback will be run. A value of 1.0 means that the threshold isn't considered passed until every pixel is visible.	0
intersectionMargin	string	:x:	Margin around the placeholder. Can have values similar to the CSS margin property (top, right, bottom, left). The values can be percentages. This set of values serves to grow or shrink each side of the placeholder element's bounding box before computing intersections.	"0px 0px 0px 0px"
lazyLoad	Boolean	:x:	Wheter enable lazy loading or not	true
explicitWidth	Boolean	:x:	Wheter the image wrapper should explicitely declare the width of the image or keep it fluid	false

The ResponsiveImage object

The data prop expects an object with the same shape as the one returned by responsiveImage GraphQL call. It's up to you to make a GraphQL query that will return the properties you need for a specific use of the <Image> component.

• The minimum required properties for data are: aspectRatio, width, sizes, srcSet and src;
• alt and title, while not mandatory, are all highly suggested, so remember to use them!
• You either want to add the webpSrcSet field or specify { auto: format } in your imgixParams, to automatically use WebP images in browsers that support the format;
• If you provide both the bgColor and base64 property, the latter will take precedence, so just avoiding querying both fields at the same time, it will only make the response bigger :wink:

Here's a complete recap of what responsiveImage offers:

property	type	required	description
aspectRatio	float	:white_check_mark:	The aspect ratio (width/height) of the image
width	integer	:white_check_mark:	The width of the image
height	integer	:white_check_mark:	The height of the image
sizes	string	:white_check_mark:	The HTML5 sizes attribute for the image
srcSet	string	:white_check_mark:	The HTML5 srcSet attribute for the image
src	string	:white_check_mark:	The fallback src attribute for the image
webpSrcSet	string	:x:	The HTML5 srcSet attribute for the image in WebP format, for browsers that support the format
alt	string	:x:	Alternate text (alt) for the image
title	string	:x:	Title attribute (title) for the image
bgColor	string	:x:	The background color for the image placeholder
base64	string	:x:	A base64-encoded thumbnail to offer during image loading

Social share, SEO and Favicon meta tags

Just like the image component, renderMetaTags() is a helper specially designed to work seamlessly with DatoCMS’s _seoMetaTags and faviconMetaTags GraphQL queries so that you can handle proper SEO in your pages with a simple one-liner.

Usage

renderMetaTags() takes an array of Tags in the exact form they're returned by the following DatoCMS GraphQL API queries:

• _seoMetaTags query on any record, or
• faviconMetaTags on the global _site object.

You can concat multiple array of Tags together and pass them to a single renderMetaTags() call.

Example

For a working example take a look at our examples directory.

import React from "react";
import { renderMetaTags } from "react-datocms";

const Page = ({ data }) => (
  <div>
    <Helmet>{renderMetaTags(data.page.seo.concat(data.site.favicon))}</Helmet>
    <h1>{data.page.title}</h1>
  </div>
);

const query = gql`
  query {
    page: homepage {
      title
      seo: _seoMetaTags {
        attributes
        content
        tag
      }
    }

    site: _site {
      favicon: faviconMetaTags {
        attributes
        content
        tag
      }
    }
  }
`;

export default withQuery(query)(Page);