Static websites with GatsbyJS and Enonic XP

Contents

This guide takes you through the basics of building Gatsby sites using data from Enonic XP.

This guide assumes you are already familiar with Gatsby and Enonic XP, and have both Gatsby CLI and Enonic CLI installed in your system. If not, we recommend looking into these tutorials before commencing:

Introduction

Gatsby sites are created from various data sources. Throughout this guide we will use Enonic XP’s headless API, also known as project Guillotine.

The headless CMS API is based on graphQL, which is a natural companion for Gatsby. Throughout this guide we will be using a dataset called the Headless Move Database.

We have also developed a Gatsby plugin that simplifies the integration between Gatsby and Enonic XP even further.

tl;dr

To skip to the end of the tutorial and run a pre-assembled version, follow these simple steps:

  1. Launch Enonic XP, create and deploy an Enonic project based on Headless Movie DB in a clean sandbox

    enonic project create -r app-hmdb
    cd myproject
    enonic project deploy
    Accept default values for project name (com.example.myproject) and version suggested by CLI while creating the project
  2. Verify that the API is available on http://localhost:8080/site/hmdb/draft/hmdb/_graphql

  3. Create a new Gatsby project as follows:

    gatsby new tldr https://github.com/enonic/guide-gatsby-starter
    ...
    cd tldr
    gatsby develop
  4. The generated site should now be available on http://localhost:8000

Headless Movie Database

Let’s start by setting up an XP project with a suitable dataset and the headless API. The Headless Movie Database is a set of sample data about Movies and Persons (actors and directors).

Let’s get going:

  1. Create a new project using the headless starter

    The following command creates a project based on the headless starter:

    enonic project create -r app-hmdb
    Stick with the standard values and use the project name com.example.myproject for the tutorial examples to work properly.
  2. Deploy the application

    enonic project deploy

    The application will now be installed, and the content imported.

    From Content Studio, the site will look something like this:

    Headless Movie Database site in Content Studio
  3. Access the API

    The API and the draft content should now be accessible on http://localhost:8080/site/hmdb/draft/hmdb/_graphql

    GraphQL playground

    The interface served when we access the endpoint lets us browse the API directly. Use the tabs on the far right to discover. Use the left hand field to run queries, and the result will be presented in the right hand field.

    New to GraphQL? Check out the GraphQL documentation.

Running queries

One of the objectives with this tutorial is listing and presenting movies. Using the Headless API interface, lets run a simple query that retrieve movies:

Query to fetch movies from Headless API
{
  guillotine {
    query(contentTypes: "com.example.myproject:movie", query: "valid='true'", sort: "displayName") {
      id: _id
      displayName
    }
  }
}
GraphQL query to retrieve movies

The GraphQL query interestingly has a field called query. Interestingly, this actually exposes XP’s content API query function. We pass the following parameters to the function:

contentTypes

Fetch only content of the specific type com.example.myproject:movie.

com.example.myproject represents your application name (the one you used when creating the XP project).
query: "valid='true'"

Filter out items that don’t have all of the mandatory fields filled out. This is only relevant for draft items, as only valid items can be published.

sort: "displayName"

To sort the list by name

Additionally, the query specifies to get the fiels id and displayName.

Content type specific fields can be accessed through introspection …​ on com_example_myproject_Movie where you again use the application name.

Static Movie Database project

The following steps assume you have already installed the Gatsby developer environment, including Node.js, Git and the Gatsby CLI
  1. Create a new Gatsby project

    We’ll call it the "Static Movie DataBase" or SMDB for short. Simply run this command in your terminal:

    gatsby new smdb https://github.com/gatsbyjs/gatsby-starter-default
    When the site wizard asks you which package manager you would like to use for your new site, choose NPM

    The command creates the following project file structure:

    Gatsby movie datbase project structure:
    SMDB
    src/
      components/
      images/
      pages/
    gatsby-config.js
    package-lock.json
    package.json
  2. Start the Gatsby development server

    To start your local Gatsby build server, run the following command:

    gatsby develop

    You should now have a Gatsby development server running on http://localhost:8000/.

    Gatsby Default Starter

Enonic Gatsby plugin

Gatsby can fetch content directly from Enonic’s GraphQL API, and then programmatically use the content to create pages. However, to simplify the process we’ll use Enonic’s Gatsby plugin instead.

  1. Install plugin

    Stop your Gatsby instance. And run the following command:

    npm install gatsby-plugin-enonic

    The gatsby-plugin-enonic is now downloaded from NPM and adds a dependency to the package.json file inside your project folder.

    Once completed, start the Gatsby development environment again, this time the plugin should be automatically loaded as well.

  2. Configure the plugin

    Open the file gatsby-config.js, it is located in your project root folder. This file is where you configure plugins used by the project.

    Add this config inside the plugins [] array of your config, like this:

    Base config for gatsby-config.js
    // First parts of config file
    plugins [
    {
      resolve: `gatsby-plugin-enonic`,
      options: {
        api: 'http://localhost:8080/site/hmdb/draft/hmdb/_graphql',
        refetchInterval: 10,
      }
    },
    // other plugins go here
    ]
    // Last parts of config file

    Details on the plugins configuration options:

    api

    URL to the specific headless API.

    refetchInterval (optional)

    How frequently you want Gatsby to pull XP for new content (in seconds). You don’t want this to be too often since a new request will be sent to server every time to fetch the data.

    With both XP and Gatsby setup, we’re ready to start buildig the site.

Movies page

The plugin supports two types of pages: list and details. Let’s start by setting up a page for listing Movies.

Create query

We will start by setting up a query to fetch movies from Enonic XP.

  1. Create a new folder src/queries/ in your Gatsby project.

  2. In src/queries create a file called getMovies.js

    Add the following code to the file. If you look closely, you will recognise the query used to fetch movies. However, this time it is wrapped in JavaScript.

    src/queries/getMovies.js
    const query = `{
      guillotine {
        query(contentTypes: "com.enonic.myproject:movie", query: "valid='true'", sort: "displayName") {
          id: _id
          displayName
        }
      }
    }
    `
    module.exports = query;
    This query is the same query as we used when testing the headless API earlier.

Create template

To present the list of movies we will need a template.

  1. Create a new folder /src/templates in your Gatsby project.

  2. Create the file /src/templates/list.js with the following content:

    src/templates/list.js
    import React from "react"
    import Layout from "../components/layout"
    import Seo from "../components/seo"
    
    const ListPage = (args) => {
        const { pageContext } = args
        return (
          <Layout>
            <Seo title={pageContext.title || `List`} />
            <h1>{pageContext.title}</h1>
              {
                  pageContext.nodes.map(node => (
                    <div key={node.id}>
                        <span>{node.displayName}</span>
                    </div>
              ))
              }<br/>
          </Layout>
        )
    }
    
    export default ListPage

    Gatsby operates with React components. Our listing page const ListPage is also a React component. It takes a pageContext argument which contains the list of nodes generated from our query. The component iterates through the array of nodes and for every node it outputs a <div> with unique key (node.id) and an item’s display name (node.displayName).

    <Seo> is another React component that comes with the Gatsby starter. It generates various Seo tags. By passing the title argument to it (like we do above) it will use the page title in Seo tags and display the specified title in the browser tab.

Create page

We now need to instruct the plugin to generate the movies page, by combining the query and template created earlier.

  1. Update the plugin configuration with instructions for creating the movies page

    Update for gatsby-config.js
    {
      resolve: `gatsby-plugin-enonic`,
      options: {
        api: 'http://localhost:8080/site/hmdb/draft/hmdb/_graphql',
        refetchInterval: 10,
        pages: [{
          query: require.resolve('./src/queries/getMovies'),
          list: {
            url: '/movies',
            template: require.resolve('./src/templates/list'),
            title: 'Movies'
          }
        }]
      }
    },

    The new pages entry gives instructions on how to generate the movies page by combining a query and a template.

  2. Generate page

    When making changes to a query, or plugin configuration, the Gatsby development server must be restarted. (press Ctrl + C to stop, then run gatsby develop once again)

    If everything was configured properly, you will see logs indicating that the site is built and that the Gatsby development server is ready to serve the content.

  3. Open the Gatsby site at http://localhost:8000/movies, and you should see the following:

    Movies listing

    Congratulations! You just created your first Gatsby page with content from Enonic XP.

    Getting errors? Double-check the previous steps to make sure you didn’t miss anything, and verify that Enonic XP is running on port 8080.

Persons page

This time, we repeat the steps from the movies listing page, but with a few adjustments:

  1. Create the persons query file

    This time we’re fetching some more data for persons, such as person images, as we will need this later.
    src/queries/getPersons.js
    const query = `{
      guillotine {
        query(contentTypes: "com.example.myproject:person", query: "valid='true'", sort: "displayName", first: 100) {
          id: _id
          displayName
          name: _name
          ... on com_example_myproject_Person {
            data {
              bio
              photos {
                ... on media_Image {
                  imageUrl: imageUrl(type: absolute, scale: "width(300)")
                  attachments {
                    altName: name
                  }
                }
              }
            }
          }
      }
      }
    }`
    
    module.exports = query;
  2. Add the persons page to your plugin configuration.

    Update for gatsby-config.js
    {
      resolve: `gatsby-plugin-enonic`,
      options: {
        api: 'http://localhost:8080/site/hmdb/draft/hmdb/_graphql',
        refetchInterval: 10,
        pages: [{
          query: require.resolve('./src/queries/getMovies'),
          list: {
            url: '/movies',
            template: require.resolve('./src/templates/list'),
            title: 'Movies'
          }
        },
        {
          query: require.resolve('./src/queries/getPersons'),
          list: {
            url: '/persons',
            template: require.resolve('./src/templates/list'),
            title: 'Persons'
          }
        }]
      }
    },
    We simply reuse the template we used for listing movies.
  3. Open the persons page to verify that it works: http://localhost:8000/persons

    It should look somethinglike this:

    Persons list page

The page only lists 10 persons, but there are more in XP. To list more, you can increase this limit by adding first: N parameter to the query.

query(contentTypes: "com.example.myproject:person", query: "valid='true'", sort: "displayName", first: 100)

Now, lets add a link from the main page to the movies and persons pages.

  1. Load the site front page in your browser: http://localhost:8000

  2. Open the main page file /src/pages/index.js, and update it with the following content:

    /src/pages/index.js
    import React from "react"
    import { Link } from "gatsby"
    import Layout from "../components/layout"
    import { XpLogo } from "../components/xpLogo"
    import Seo from "../components/seo"
    
    const IndexPage = () => (
      <Layout>
        <Seo title="Home" />
        <h1>Hi people</h1>
        <p>Welcome to your new Gatsby site.</p>
        <p>Now go build something great.</p>
        <div style={{ maxWidth: `300px`, marginBottom: `1.45rem` }}>
          <XpLogo />
        </div>
        <div style={{ marginBottom: `1rem` }}>
          <Link to="/movies/">Open movies</Link><br/>
          <Link to="/persons/">Open persons</Link>
        </div>
    
      </Layout>
    )
    
    export default IndexPage

    The page should refresh automatically in your browser, and you will see this:

    Main page with links
  3. Click the links to verify that they work!

Movie details page

Next we want to create pages that represent each specific movie.

We’ll use the plugin to generate a page for every movie retrieved from the storage.

Each movie will also need a unique URL. By default the plugin uses the id field, which is alway unique. However XP always provides a URL-friendly name field (AKA slug) as well. This field is unique within it’s location of the content structure, and fits perfectly for our use case.

Fields from the Movie content type

Update movie query

For every movie we want to show an abstract, release date, and a movie image. This means we need to modify our query as well.

  1. Update the movie query to fetch more fields.

    src/queries/getMovies.js
    const query = `{
      guillotine {
        query(contentTypes: "com.example.myproject:movie", query: "valid='true'", sort: "displayName") {
          id: _id
          displayName
          name: _name
          ... on com_example_myproject_Movie {
            data {
              subtitle
              abstract
              photos {
                ... on media_Image {
                  imageUrl: imageUrl(type: absolute, scale: "width(300)")
                  attachments {
                    imageText: name
                  }
                }
              }
            }
          }
        }
      }
    }
    `
    
    module.exports = query;
    Lines with colons are for aliases - field names that you want to use instead of original names. For example, if you want to use name instead of original _name then you do name: _name
  2. Verify query:

    By running the above query directly in XP, we get the following result:

    Query result for movie details

    Notice how the result now includes a lot of new data, including links to images.

Movie details template

Next we need a new template to display all the movie details.

  1. Create a new templates file

    src/templates/movie.js
    import React from "react"
    import Layout from "../components/layout"
    import Seo from "../components/seo"
    
    const getPageTitle = (pageContext) => {
      const node = pageContext.node;
    
      if (!!node && pageContext.title && (node[pageContext.title] || node.data[pageContext.title])) {
        return node[pageContext.title] || node.data[pageContext.title];
      }
    
      return pageContext.title || 'Person';
    };
    
    const MoviePage = (args) => {
        const { pageContext } = args;
        const movie = pageContext.node;
        const movieMeta = movie.data;
    
        return (
          <Layout>
            <Seo title={getPageTitle(pageContext)} />
            <div>
              <div style={{
                  display: 'flex',
                  alignItems: 'baseline'
                }}>
                <h2>{movie.displayName}
                {movieMeta.release && (
                  <i style={{
                    fontStyle: 'normal',
                    fontWeight: 'normal',
                    fontSize: '24px',
                    marginLeft: '10px',
                    opacity: '0.7'
                  }}>({new Date(movieMeta.release).getFullYear()})</i>
                )}
                </h2>
              </div>
              <div style={{
                  display: `flex`
                }}>
                <img
                  style={{
                    maxWidth: '400px',
                    width: '50%'
                  }}
                  src={movieMeta.photos[0].imageUrl} title={movieMeta.subtitle} alt={movieMeta.photos[0].attachments[0].imageText} />
                <p style={{
                    margin: `0 20px`
                }}><i>{movieMeta.abstract}</i></p>
              </div>
            </div>
          </Layout>
        )
    }
    
    export default MoviePage

    This template is of course just an example, using inline styling and other dirty tricks. Feel free to customize it later :-).

Update plugin

Lets configure the plugin to generate the movie detail pages.

  1. Update your Gatsby configuration

    Update for gatsby-config.js
    {
      resolve: `gatsby-plugin-enonic`,
      options: {
        api: 'http://localhost:8080/site/hmdb/draft/hmdb/_graphql',
        refetchInterval: 10,
        pages: [{
          query: require.resolve('./src/queries/getMovies'),
          list: {
            url: '/movies',
            template: require.resolve('./src/templates/list'),
            title: 'Movies'
          },
          details: {
            template: require.resolve('./src/templates/movie'),
            key: 'name',
            title: 'displayName'
          }
        },
        {
          query: require.resolve('./src/queries/getPersons'),
          list: {
            url: '/persons',
            template: require.resolve('./src/templates/list'),
            title: 'Persons'
          }
        }]
      }
    },

    Notice how the new details section is placed into the same page configuration as the list page. This basically means we re-use the query to also generate the details page.

    The new config options for detail pages are:

    url (optional)

    Base url of the details page. If omitted, value from pages.list.url will be used. In our case, the pages will be created as /movies/{key}.

    key (optional)

    Specify the field in the query whose value will be used as key for the details page url. Default is _id. In our case, we are using the name field.

  2. Visit one of the movie pages to see the glorious result: http://localhost:8000/movies/pulp-fiction

    Movie details page

    Simple but pretty good looking huh?

Generating pages is fine, but we also need to configure our list to link to the actual movies.

  1. Update the list template to make use of Gatsby’s Link component:

    src/templates/list.js
    import React from "react"
    import Layout from "../components/layout"
    import Seo from "../components/seo"
    import {Link} from "gatsby";
    
    const ListPage = (args) => {
        const { pageContext } = args
        return (
          <Layout>
            <Seo title={pageContext.title || `List`} />
            <h1>{pageContext.title}</h1>
              {
                  pageContext.nodes.map(node => (
                    <div key={node.id}>
                        {pageContext.detailsPageUrl &&
                            <Link to={`${pageContext.detailsPageUrl}/${node[pageContext.detailsPageKey]}`}>
                                {node.displayName}
                            </Link>
                        }
                        {!pageContext.detailsPageUrl && <span>{node.displayName}</span>}
                    </div>
              ))
              }<br/>
          </Layout>
        )
    }
    
    export default ListPage
  2. The list page should refresh automatically, and you will see that the movie list has now turned into a list of links.

    Movie list with link to the details pages

    Click any link in the list to open our new movie details page:

Person details

By repeating some of the steps above, we can create detail pages for persons as well.

  1. Add a person template

    src/templates/person.js
    import React from "react"
    import Layout from "../components/layout"
    import Seo from "../components/seo"
    import {Link} from "gatsby";
    
    const getPageTitle = (pageContext) => {
      const node = pageContext.node;
    
      if (!!node && pageContext.title && (node[pageContext.title] || node.data[pageContext.title])) {
        return node[pageContext.title] || node.data[pageContext.title];
      }
    
      return pageContext.title || 'Person';
    };
    
    const PersonPage = (args) => {
      const { pageContext } = args;
      const person = pageContext.node;
      const personMeta = person.data;
    
        return (
          <Layout>
            <Seo title={getPageTitle(pageContext)} />
            <div>
              <div style={{
                display: 'flex',
                alignItems: 'baseline'
              }}>
                <h2>{person.displayName}</h2>
              </div>
              <div style={{
                display: `flex`
              }}>
                <img
                  style={{
                    maxWidth: '400px',
                    width: '50%'
                  }}
                  src={personMeta.photos[0].imageUrl} title={person.displayName} alt={personMeta.photos[0].attachments[0].altImageText} />
                <p style={{
                  margin: `0 20px`
                }}><i>{personMeta.bio}</i></p>
              </div>
            </div>
            <p>
              <Link to={`${pageContext.listPageUrl}`}>Back to Persons</Link>
            </p>
          </Layout>
        )
    }
    
    export default PersonPage
    You could later try to move the getPageTitle() function to a separate helper class since it’s exactly the same as the one in the Movie details page.
  2. Update plugin config to generate person detail pages

    Update for gatsby-config.js
        {
          resolve: `gatsby-plugin-enonic`,
          options: {
            api: 'http://localhost:8080/site/hmdb/draft/hmdb/_graphql',
            refetchInterval: 10,
            pages: [{
              query: require.resolve('./src/queries/getMovies'),
              list: {
                url: '/movies',
                template: require.resolve('./src/templates/list'),
                title: 'Movies'
              },
              details: {
                template: require.resolve('./src/templates/movie'),
                key: 'name',
                title: 'displayName'
              }
            },
            {
              query: require.resolve('./src/queries/getPersons'),
              list: {
                url: '/persons',
                template: require.resolve('./src/templates/list'),
                title: 'Persons'
              },
              details: {
                template: require.resolve('./src/templates/person'),
                key: 'name',
                title: 'displayName'
              }
            }]
          }
        },
  3. Restart your Gatsby development server and check out the new pages:

    Person list with links to the details pages
    Person details page

Cross-referencing

To enliven our movie page further. Let’s display cast for each movie on the movie’s details page. We’ll add movie characters, including name, actor, actor’s photo, and link to the actor’s detail page.

  1. Update the movie query to also extract the cast.

    src/queries/getMovies.js
    const query = `{
      guillotine {
        query(contentTypes: "com.example.myproject:movie", query: "valid='true'", sort: "displayName") {
          id: _id
          displayName
          name: _name
          ... on com_example_myproject_Movie {
            data {
              subtitle
              abstract
              photos {
                ... on media_Image {
                  imageUrl: imageUrl(type: absolute, scale: "width(300)")
                  attachments {
                    imageText: name
                  }
                }
              }
              cast {
                character
                actor {
                  id: _id
                  name: _name
                  displayName
                  ... on com_example_myproject_Person {
                    data {
                      photos {
                        ... on media_Image {
                          imageUrl: imageUrl(type: absolute, scale: "block(100,100)")
                        }
                      }
                    }
                  }
                }
              }
            }
          }
        }
      }
    }`
    
    module.exports = query;
    We include the name field of the persons, as we will use use it to link back to the actor’s detail page.
  2. Update the movie template to list the cast

    src/templates/movie.js
    import React from "react"
    import Layout from "../components/layout"
    import Seo from "../components/seo"
    import {Link} from "gatsby"
    
    const getPageTitle = (pageContext) => {
      const node = pageContext.node;
    
      if (!!node && pageContext.title && (node[pageContext.title] || node.data[pageContext.title])) {
        return node[pageContext.title] || node.data[pageContext.title];
      }
    
      return pageContext.title || 'Person';
    };
    
    const MoviePage = (args) => {
      const { pageContext } = args;
      const movie = pageContext.node;
      const movieMeta = movie.data;
    
      return (
        <Layout>
          <Seo title={getPageTitle(pageContext)} />
          <div>
            <div style={{
                display: 'flex',
                alignItems: 'baseline'
              }}>
              <h2>{movie.displayName}
              {movieMeta.release && (
                <i style={{
                  fontStyle: 'normal',
                  fontWeight: 'normal',
                  fontSize: '24px',
                  marginLeft: '10px',
                  opacity: '0.7'
                }}>({new Date(movieMeta.release).getFullYear()})</i>
              )}
              </h2>
            </div>
            <div style={{
                display: `flex`
              }}>
              <img
                style={{
                  maxWidth: '400px',
                  width: '50%'
                }}
                src={movieMeta.photos[0].imageUrl} title={movieMeta.subtitle} alt={movieMeta.photos[0].attachments[0].imageText} />
              <div style={{
                    margin: `0 20px`
                }}>
                <p><i>{movieMeta.abstract}</i></p>
                {movieMeta.cast && (
                  <>
                    <h4>Cast</h4>
                    <div style={{
                        display: `flex`,
                        padding: '0 15px'
                      }}>
                      {
                        movieMeta.cast.map(cast => (
                          <div
                            key={cast.actor.id}
                            style={{
                              flex: '1 1 0px',
                              display: `flex`,
                              flexDirection: `column`
                            }}
                          >
                            <img
                              style={{
                                width: '50%',
                                marginBottom: '0.5rem'
                              }}
                              src={cast.actor.data.photos[0].imageUrl} title={`${cast.actor.displayName} as ${cast.character}`} alt={cast.character} />
                              <div
                                style={{
                                  display: `flex`,
                                  flexDirection: `column`
                                }}>
                                <i
                                  style={{
                                    fontSize: '14px'
                                }}>{cast.character}</i>
                                <Link to={`/persons/${cast.actor.name}`}>
                                    <span
                                      style={{
                                        fontSize: '14px'
                                    }}>{cast.actor.displayName}</span>
                                </Link>
                              </div>
                          </div>
    
                        ))
                      }
                    </div>
                  </>
                )}
              </div>
            </div>
          </div>
          <p>
            <Link to={`${pageContext.listPageUrl}`}>Back to Movies</Link>
          </p>
        </Layout>
      )
    }
    
    export default MoviePage
  3. Restart the Gatsby dev server once more, open any movie page and embrace the result:

    Movie details page with cast

Going live

So far, we have been accessing draft content. This is indeed useful when developing, or setting up a preview environment. However, for production purposes we need to render the site using published content only.

  1. Publish the HMDB site

    Visit Content Studio, select the HMDB`site and choose `Publish tree from the top right workflow menu. From the dialog, click Publish Now to complete the action.

    Publish all items

    By publishing, your content is "merged" to the master branch. So far we have only been accessing the draft branch.

  2. Verify that both your API and content is live

    Visiting the following URL should open the API playground: http://localhost:8080/site/hmdb/draft/hmdb/_graphql

  3. Update your plugin configuration to read from master branch.

    Update for gatsby-config.js
    {
      resolve: `gatsby-plugin-enonic`,
      options: {
        api: 'http://localhost:8080/site/hmdb/master/hmdb/api',
        refetchInterval: 10,
        pages: [{
          query: require.resolve('./src/queries/getMovies'),
          list: {
            url: '/movies',
            template: require.resolve('./src/templates/list'),
            title: 'Movies'
          },
          details: {
            template: require.resolve('./src/templates/movie'),
            key: 'name',
            title: 'displayName'
          }
        },
        {
          query: require.resolve('./src/queries/getPersons'),
          list: {
            url: '/persons',
            template: require.resolve('./src/templates/list'),
            title: 'Persons'
          },
          details: {
            template: require.resolve('./src/templates/person'),
            key: 'name',
            title: 'displayName'
          }
        }]
      }
    }
  4. Verify the site

    Restart Gatsby once more to pickup the new site, and verify that everything is generated like before on http://localhost:8000

  5. Finally, test updating and publishing content

    Try editing an existing content (updating the draft branch), verify that nothing happes on the Gatsby server.

    Publish the content, and Gatsby will re-generate your site with the updated content within a couple of seconds.

    Gatsby will only generate new pages when restarted.

Congratulations! You have now built a simple Gatsby site rendering static pages based on content from Enonic XP.


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