Assets

The Asset model is included with every project, can be modified with custom Field Types, and are localized by default, but cannot be deleted.

While most commonly used for photos, can support any file type including audio files, zip files, and more.

The Asset type extends the system fields.

#Fetching assets

Hygraph automatically generates 4 query types for assets. These are:

• asset
• assets
• assetVersion
• assetsConnection

These queries work just like regular queries, and can be filtered by their fields.

#Referencing assets

While you can query for individuals assets, or fetch all and filter, order, and paginate, assets are best used when related to another model.

When extending the Hygraph schema with your own models, the Asset field type exposes all of the available transformations below.

For example, imagine you have a Product model with a one to many reference to assets, as images, you can query any of the system fields here also.

{
  product(where: { slug: "..." }) {
    images {
      url
      height
      width
    }
  }
}

#Transformations

When fetching assets, you can pass an optional transformation argument to the url field.

#Resize images

The image takes the following arguments:

The ImageFit takes one of the following values:

For example, we can query all assets, and resize images:

{
  assets {
    url(
      transformation: {
        image: { resize: { width: 50, height: 50, fit: clip } }
      }
    )
  }
}

#Convert file type

Depending on the asset type you're dealing with, it's possible to transform the output to another file type by passing a format value.

For example, let's transform all assets to PDFs:

{
  assets {
    url(transformation: { document: { output: { format: pdf } } })
  }
}

#Validating transforms

We provide a validation field you can enable to check the combination of transform arguments are valid.

For example, you may query a video, and request to change the file type to pdf. validateOptions: true will warn you that this is not permitted.

{
  assets {
    url(
      transformation: {
        document: { output: { format: pdf } }
        validateOptions: true
      }
    )
  }
}

#Combining transforms

It is possible to combine both transformation arguments:

{
  assets {
    url(
      transformation: {
        image: { resize: { width: 50, height: 50, fit: clip } }
        document: { output: { format: png } }
        validateOptions: true
      }
    )
  }
}

#Alias transforms

GraphQL aliases are great for querying the same asset url with multiple transformations.

For example, you could transform product images to include a thumbnail.

{
  products {
    images {
      thumbnail: url(
        transformation: {
          image: { resize: { width: 50, height: 50, fit: clip } }
          document: { output: { format: png } }
        }
      )
      url(transformation: { document: { output: { format: png } } })
    }
  }
}

#Uploading assets

Hygraph supports uploading assets via HTTP. You'll need a Permanement Auth Token with Mutations API access enabled to upload by file, or URL.

Assets are treated just like any other content entry, so they are automatically bound to the environment, and authorization settings of your project.

#Upload by file

Here's also a standard JavaScript example:

const HYGRAPH_URL = '';
const HYGRAPH_ASSET_TOKEN = '';

async function upload() {
  const input = document.getElementById('fileUpload');
  const file = input.files[0];

  const form = new FormData();

  form.append('fileUpload', file);

  // It is not recommended to use the HYGRAPH_ASSET_TOKEN in the Front-End.
  // In this example we're using it, but in a real application you should
  // use a backend to upload the file and use the HYGRAPH_ASSET_TOKEN there.
  const response = await fetch(`${HYGRAPH_URL}/upload`, {
    method: 'POST',
    headers: {
      Authorization: `Bearer ${HYGRAPH_ASSET_TOKEN}`,
    },
    body: form,
  });

  const data = await response.json();
  console.log(JSON.stringify(data, null, 2));
}

#Upload by remote URL

You can also upload files by providing a remote URL, instead of a file.

#Updating assets

Since assets are a system model, and automatically added to every project, you can extend them with your own custom fields.

These fields can be updated using GraphQL mutations. For example, some users add a caption field to assets:

mutation {
  updateAsset(where: { id: "..." }, data: { caption: "..." }) {
    id
  }
}

Learn more about Mutations.

#Deleting assets

Hygraph exposes a deleteAsset mutation that you can use to delete any unwanted assets.

Simply pass the id of the asset you want deleted:

mutation {
  deleteAsset(where: { id: "..." }) {
    id
  }
}

Learn more about Mutations.

#Publishing assets

Since Assets are a system model, they also come with publishing capabilities. You can use GraphQL mutations to publish or unpublish your assets, to and from content stages.

Learn more about publishing to content stages.

#Localized assets

Since assets are localized by default, you can upload a file for your project locales.

Learn more about mutating localized content.

#Embedded types

Assets can be embedded into the Rich Text Field Type via a configuration setting. On the API side, we create a union relation that references the selected model.