storyblok-image-upload-function.js

methods: {
  ...
  storyblokImageUpload(fileblob, filename, success, failure) {
    this.api.client.post(
      `/spaces/${this.spaceId}/assets`,
      { filename: filename },
      { headers: { Authorization: this.options.oauthToken } }, // uses the option with the name `oauthToken` which needs to be configured in the schema definition of the field you're using the plugin in.
    ).then((response) => {
      
      let request = new XMLHttpRequest()
      request.withCredentials = false
      request.open('POST', response.data.post_url)

      request.onreadystatechange = () => {
        const allowedStatuses = [200, 201, 204];

        if (request.readyState === 4) {
          if (allowedStatuses.includes(request.status)) {
            // eslint-disable-next-line
            console.log('Image uploaded: ' + response.data.pretty_url)
            success({ location: response.data.pretty_url })
          } else {
            failure(new Error(`Error during upload with status: ${request.status}`));
          }
        }
      }

      let formData = new FormData()
      for (let key in response.data.fields) {
        formData.append(key, response.data.fields[key])
      }
      formData.append('file', fileblob)
      request.send(formData)
    }).catch((error) => {
      failure(error)
    })
  },
}