Image Field


The image field is used for content values that point to an image used on the page. This field allows you to upload new images by via dragging or selection in Finder. Note this field does not handle any images included in the Markdown body, those would be handled by the markdown component.

tinacms-image-field

Definition

interface ImageConfig {
  component: 'image'
  name: string
  label?: string
  description?: string
  parse(media: Media): string
  previewSrc(formValues: any)?: string
  uploadDir(formValues: any)?: string
}

KeyDescription
componentThe name of the plugin component. Always 'image'.
nameThe path to some value in the data being edited.
labelA human readable label for the field. Defaults to the name. (Optional)
descriptionDescription that expands on the purpose of the field or prompts a specific action. (Optional)
parseDefines how the actual front matter or data value gets populated. The media object gets passed as an argument, and one can set the path this image as defined by the uploadDir property.
previewSrcDefines the path for the src attribute on the image preview. If using gatsby-image, the path to the childImageSharp.fluid.src needs to be provided. _(Optional)
uploadDirDefines the upload directory for the image. All of the form data is passed in, fileRelativePath is most useful in defining the upload directory, but you can also statically define the upload directory. _(Optional)

This interfaces only shows the keys unique to the image field.

Visit the Field Config docs for a complete list of options.

Examples

Next.js

Below is an example of an image field defined in a Next.js project.

const formOptions = {
  fields: [
    {
      label: 'Hero Image',
      name: 'frontmatter.hero_image',
      component: 'image',
      // Generate the frontmatter value based on the filename
      parse: media => `/static/${media.filename}`,

      // Decide the file upload directory for the post
      uploadDir: () => '/public/static/',

      // Generate the src attribute for the preview image.
      previewSrc: fullSrc => fullSrc.replace('/public', ''),
    },
  ],
  //...
}

Gatsby

Below is an example of how a image field could be defined in a Gatsby Remark form. Read more on passing in form field options in the Gatsby Markdown Docs.

const BlogPostForm = {
  fields: [
    {
      label: 'Hero Image',
      name: 'rawFrontmatter.hero.image',
      component: 'image',
      parse: media => {
        if (!media) return ''
        return `../images/${media.filename}`
      },
      uploadDir: () => `/content/images/`,
      previewSrc: (src, path, formValues) => {
        if (!formValues.frontmatter.hero || !formValues.frontmatter.hero.image)
          return ''

        return formValues.frontmatter.hero.image.childImageSharp.fluid.src
      },
    },
    // ...
  ],
}

Proper Image Paths in Gatsby

In order for image paths to be properly sourced into GraphQL, it's best if a relative path to the image is saved to the content file's front matter. Constructing this relative path will depend on where the image is uploaded to as well as the location of the content file. The following example uses a co-location strategy, where a blog post is stored in content/blog/$slug/index.md and its images will be uploaded to content/blog/$slug/$image.png:

import get from 'lodash.get'
const path = require('path').posix

const BlogPostForm = {
  fields: [
    {
      name: 'rawFrontmatter.thumbnail',
      label: 'Thumbnail',
      component: 'image',
      previewSrc: (src, path, formValues) => {
        if (!formValues.frontmatter.thumbnail) return ''

        return formValues.frontmatter.thumbnail.childImageSharp.fluid.src
      },

      // upload images to same directory as content file
      uploadDir: formValues => path.dirname(formValues.fileRelativePath),

      // image file is sibling of content file
      parse: filename => `./${filename}`,
    },
    // ...
  ],
}