You can send a Webhook notification when media is changed (created/updated/deleted).
This can be configured from "Media Management" → "Media Settings".

Webhook Timing

You can set the timing for issuing Webhooks when configuring each Webhook.

When Creating Media

Notifications will be sent when new media is created (uploaded) in the management screen.

When Updating Media

Notifications will be sent when media is re-uploaded in the management screen or when the file name is changed.

When Deleting Media

Notifications will be sent when media is deleted from the management screen.

About Webhook Notifications

The media webhook notifications send POST requests to a specified URL. The receiving end can perform custom processing upon receiving the request.

Request Details

Header

The request header includes Content-Type: application/json.

Body

The request body contains information about the affected content and API.

{
  "service": "someId",
  "type": "edit",
  "old": {
    "url": "https://images.microcms-assets.io/assets/xxxx/yyyy/zzzz.jpg",
    "width": 100,
    "height": 100,
    "alt": "Some sample alt text."
  },
  "new": {
    "url": "https://images.microcms-assets.io/assets/xxxx/yyyy/zzzz.jpg",
    "width": 100,
    "height": 100,
    "alt": "Some sample alt text."
  },
}

service

This contains the subdomain of the service to which the modified media belongs.

type 

This indicates the type of change. For new additions, it will be new; for edits, edit; and for deletions, delete.

old

This contains the content before the media was edited or deleted. It will be null when a new media is created.

new

This contains the content after the media has been created or edited. It will be null when the media is deleted.

Common to old / new

url

This contains the URL of the media.

width

This contains the width of the media. It will be null for non-image files.

height

This contains the height of the media. It will be null for non-image files.

alt

This contains the alternative text set from the media management screen. If there is no setting or for non-image files, the key itself will not be included.

Security

The server receiving notifications from microCMS must be publicly accessible.
Therefore, depending on the processing, it is necessary to consider measures that account for the possibility of receiving POST requests from third parties.

Specifically, when setting the URL, you can configure a value known only to microCMS and the receiving server, such as ?auth=XXX, and verify whether this value is correct on the receiving server (i.e., whether the request is from microCMS).

Webhook Detailed Specifications

Retry

Retry processing will not be performed even if the webhook notification fails due to network errors or 4xx, 5xx errors.

Duplicate Sending

Webhook notifications will be sentonly once for each configured timing.

Order Guarantee

In principle, webhook notifications are sent in the order of operations executed.
However, since strict control is not implemented, the order is not guaranteed.

Source IP Address

The source IP address of the webhook is a dynamic IP address.
Additionally, the range of IP addresses is not publicly disclosed.