Adding READMEs and Icons to Apps in Happa

Your beautiful app deserves to look beautiful in Happa as well. Here are some tips and tricks on how to set the Chart.yaml values of your app so that the frontend can show relevant information in a pleasing way.

Sample of an App in Happa

It’s in the Chart.yaml

The metadata that Happa eventually sees starts in the Chart.yaml in the app’s repository.

Here is an example from jaeger-operator:

# Chart.yaml

apiVersion: v2
appVersion: 1.17.1
version: [[ .Version ]]
name: jaeger-operator
description: |
  Jaeger operator is a implementation of the operator pattern for installing
  and managing Jaeger deployments.  
kubeVersion: ^1.15.0-0
annotations:[[ .Version ]]/ team-cabbage

View Chart.yaml in Github

Happa is designed to work with 2 types of image assets for apps:

1. Icon

Every app should have an icon, and it must fit a square space.

A good example:

Good example of an app icon

A bad example:

Bad example of an app icon

While the icon in the second example also technically fits into a square space, it is not designed for it, as evidenced by the unused vertical space. The resulting icon is also difficult to discern when displayed in a space-constrained area.

Icons can be made available to happa by adding a URL to a PNG or SVG file in the Chart.yaml’s icon field.

An app may also have a logo for the catalog, to optimize its display in a rectangular space. Logos should only be provided if they have a different shape than the app’s icon. The ideal width:height ratio of logos is 2:1.

For example:

Example of an app logo displayed in the app catalog list in happa

Logos can be made available to happa using the annotation.

Providing app icons for light and dark backgrounds

We publish app icons through web-assets. Find them in the assets/app-icons folder.

Since our app catalog UI in happa (our web UI) shows app icons on a dark background, there is a chance that an icon/logo would end up invisible because it uses black on a dark blue background. To avoid this, you can provide two versions of the icon file and name the files following a specific pattern.


Here is how that works.

  1. Make two versions of the app icon. One that works on a light background, one that works on a dark background.
  2. Store the one that works on light background with a file name ending in light.svg or light.png.
  3. Store the one that works on dark background with a file name ending in dark.svg or dark.png.
  4. In the app metadata, reference the URL ending in light.svg or light.png.

Note: Please use either the SVG or PNG file format. Make sure to use lowercase file names. Make sure both file names only differ in the end at (light|dark).(svg|png) and the files reside in the same folder.


Happa will attempt to fetch the url in the value of annotation and display it when users visit the detail page of that app.

Apps packaged using CircleCI job push-to-app-catalog with executor: "app-build-suite" automatically include an annotation with key which points to a versioned copy of the apps README residing in the app catalog.

You can find more information about app metadata in spec Representation of apps and their metadata for app catalog entries.

In case you’re not using app-build-suite, it is possible to manually add an annotation called to Chart.yaml.

To make sure users see a README that matches the version of the app they are currently looking at, you can [ .Version ] to template it in.


annotations:[[ .Version ]]/

Adding a README really ties the whole thing together for people that are trying to use the app. Use it to help people understand what the app will actually do, and what values to supply in order to get a working deployment.

Sample readme outline:

  1. Installing
  2. Configuration
    1. Sample values files for the web interface and API
    2. Sample App CR and ConfigMap for the management cluster
    3. Configuration Options Reference (link to more information)
  3. Compatability
  4. Limitations
  5. For developers