Banner X previewer
This document outlines the process for retailers to integrate a banner X previewer into their workflow. This allows for complete control over the preview rendering, ensuring it matches the live website experience.
Benefits of a previewer
A previewer offers several advantages:
Advertisers can preview their banner’s appearance before launching and managing their campaign to ensure it meets expectations and standards..
Retailers can review and approve banners before they appear live on their website, ensuring consistency and quality control.
Any changes to your live site (that do not impact creative dimensions) can be made with no dependency on Epsilon Retail Media.
How it works
To give advertisers a real-time preview of how banners will appear on your site, we connect directly to your hosted previewer. This ensures banners render exactly as they would on your site. As you update your site, the previewer updates automatically, eliminating reliance on Epsilon and keeping banner rendering fully aligned with your latest changes.
Retailer-hosted integration
You can integrate your banner previewer into our platform by hosting it on your site. This ensures that the previewer is embedded in the platform window using an iframe.
Host requirements: You must host the previewer on a URL or link that you own and manage. This approach provides full flexibility to update and manage it as your site and design evolve, eliminating any dependency on our platform for changes.
Hosting recommendation: We recommend hosting the previewer at a hidden URL, such as retailer.com/banner-previewer. However, you have the discretion to choose an appropriate location.
This location may be an externalised hosted location that is not under your main domain if necessary, such as an externally accessible storage bucket or hosted solution (that is still under your maintenance).
Live site updates: You can update how images and text are rendered on your live site. Any changes you make to banners on the live site should automatically reflect in the platform via your external previewer.

How to integrate the preview specification
To display content from our platform on your external previewer, host an isolated banner previewer on a separate page you own and manage. We suggest using a URL like https://www.<retailer.com>/banner-preview/bannerx.
OpenAPI specification
Below is the OpenAPI 3.0.3 specification for implementing the BannerX preview:
Banners must remain within the capabilities of the Banner X API response.
When a user loads the previewer in the platform, a GET request is made with a set of defined parameters that are rendered on your previewer. This is then iframed within the platform.
The request will look similar to the example below:
Additional fields
The content standard supports additionalFields as a set of key value pairs. This is encoded in a custom way in the query string for the previewer. Supported field types are:
label: string value
color: A hex color value (e.g. #0a0a0a)
select: an enumerate list of strings
The fields are encoded using the following format: <key1>~<value1>_<key2>~<value2> Where:
~: key and value separator_: key/value pair separator
Reserved characters
The following characters are treated as reserved, and if they appear within either the key or value they will be encoded using the value: !<hex-code>
-
!2D
.
!2E
_
!5F
~
!7E
The remainder special characters will be URL encoded. For example, if we have the following field structure:
field-one
Has special chars: ".~_-"
field_two
# ffffff
This would be encoded in the additionalFields query parameter as: additionalFields=field!2Done~Has%20special%20chars%20%3A%20%22!2E!7E!5F!2D%22_field!5Ftwo~%23ffffff

