Red Hat Developer Hub 1.4

Customizing

Customizing Red Hat Developer Hub

Red Hat Customer Content Services

Abstract

Learn to customize Red Hat Developer Hub, such as templates, learning paths, tech docs, tech radar, home page, quick access cards, and appearance.

1. Customizing your Red Hat Developer Hub title
2. Customizing your Red Hat Developer Hub base URL
3. Customizing Red Hat Developer Hub backend secret
4. Configuring templates
5. Customizing the Learning Paths in Red Hat Developer Hub
- 5.1. Using hosted JSON files to provide data to the Learning Paths
- 5.2. Using a dedicated service to provide data to the Learning Paths
6. Configuring TechDocs
- 6.1. Configuring storage for TechDocs files
- 6.2. Configuring CI/CD to generate and publish TechDocs sites
7. Customizing the Tech Radar page in Red Hat Developer Hub
- 7.1. Using hosted JSON files to provide data to the Tech Radar page
- 7.2. Using a dedicated service to provide data to the Tech Radar page
8. Customizing Red Hat Developer Hub appearance
9. Customizing the Home page
- 9.1. Customizing the Home page cards
- 9.2. Defining the layout of the Red Hat Developer Hub Home page
10. Customizing the Quick access card
- 10.1. Using hosted JSON files to provide data to the Quick access card
- 10.2. Using a dedicated service to provide data to the Quick access card

Learn to customize Red Hat Developer Hub, such as templates, learning paths, tech docs, tech radar, home page, quick access cards, and appearance.

1. Customizing your Red Hat Developer Hub title

You can change the default Red Hat Developer Hub display name.

Prerequisites

Custom Developer Hub configuration.

Procedure

In your custom app-config.yaml file, enter your Developer Hub instance display name, such as <Red Hat Developer Hub>.
app-config.yaml excerpt
```
app:
  title: My custom Red Hat Developer Hub title
```

2. Customizing your Red Hat Developer Hub base URL

You can change the default Red Hat Developer Hub base URL.

Prerequisites

You know your desired Developer Hub external URL: https://<my_developer_hub_url>, and have configured DNS to point to your Red Hat OpenShift Container Platform cluster.
Custom Developer Hub configuration.

Procedure

In your custom app-config.yaml file, enter your Developer Hub external URL, such as https://<my_developer_hub_url>.

app-config.yaml excerpt

app:
  baseUrl: https://<my_developer_hub_url>
backend:
  baseUrl: https://<my_developer_hub_url>
  cors:
    origin: https://<my_developer_hub_url>

3. Customizing Red Hat Developer Hub backend secret

The default Red Hat Developer Hub configuration defines the Developer Hub backend secret for service to service authentication.

You can define your custom Developer Hub backend secret.

Prerequisites

You added a custom Developer Hub application configuration, and have sufficient permissions to modify it.

Procedure

To define the Developer Hub backend secret, add to your custom my-rhdh-secrets.txt file the BACKEND_SECRET environment variable with a base64 encoded string. Use a unique value for each Developer Hub instance.
```
$ echo > my-rhdh-secrets.txt "BACKEND_SECRET=$(node -p 'require("crypto").randomBytes(24).toString("base64")')"
```
my-rhdh-secrets.txt example
```
BACKEND_SECRET=3E2/rIPuZNFCtYHoxVP8wjriffnN1q/z
```

Add your backend secret to your custom app-config.yaml file.

app-config.yaml excerpt defining the backend secret

backend:
  auth:
    externalAccess:
      - type: legacy
        options:
          subject: legacy-default-config
          secret: "${BACKEND_SECRET}"

4. Configuring templates

Configure templates to create software components, and publish these components to different locations, such as the Red Hat Developer Hub software catalog, or Git repositories.

A template is a form composed of different UI fields that is defined in a YAML file. Templates include actions, which are steps that are executed in sequential order and can be executed conditionally.

4.1. Creating a template by using the Template Editor

You can create a template by using the Template Editor.

Procedure

Access the Template Editor by using one of the following options:
- Open the URL https://<rhdh_url>/create/edit for your Red Hat Developer Hub instance.
- Click Create… in the navigation menu of the Red Hat Developer Hub console, then click the overflow menu button and select Template editor.
Click Edit Template Form.
Optional: Modify the YAML definition for the parameters of your template. For more information about these parameters, see Section 4.2, “Creating a template as a YAML file”.
In the Name * field, enter a unique name for your template.
From the Owner drop-down menu, choose an owner for the template.
Click Next.
In the Repository Location view, enter the following information about the hosted repository that you want to publish the template to:
1. Select an available Host from the drop-down menu.
  Note
  Available hosts are defined in the YAML parameters by the allowedHosts field:
  Example YAML
  
  # ... ui:options: allowedHosts: - github.com # ...
2. In the Owner * field, enter an organization, user or project that the hosted repository belongs to.
3. In the Repository * field, enter the name of the hosted repository.
4. Click Review.
Review the information for accuracy, then click Create.

Verification

Click the Catalog tab in the navigation panel.
In the Kind drop-down menu, select Template.
Confirm that your template is shown in the list of existing templates.

4.2. Creating a template as a YAML file

You can create a template by defining a Template object as a YAML file.

The Template object describes the template and its metadata. It also contains required input variables and a list of actions that are executed by the scaffolding service.

Template object example

apiVersion: scaffolder.backstage.io/v1beta3
kind: Template
metadata:
  name: template-name 1
  title: Example template 2
  description: An example template for v1beta3 scaffolder. 3
spec:
  owner: backstage/techdocs-core 4
  type: service 5
  parameters: 6
    - title: Fill in some steps
      required:
        - name
      properties:
        name:
          title: Name
          type: string
          description: Unique name of the component
        owner:
          title: Owner
          type: string
          description: Owner of the component
    - title: Choose a location
      required:
        - repoUrl
      properties:
        repoUrl:
          title: Repository Location
          type: string
  steps: 7
    - id: fetch-base
      name: Fetch Base
      action: fetch:template
      # ...
  output: 8
    links:
      - title: Repository 9
        url: ${{ steps['publish'].output.remoteUrl }}
      - title: Open in catalog 10
        icon: catalog
        entityRef: ${{ steps['register'].output.entityRef }}
# ...

1

Specify a name for the template.

2

Specify a title for the template. This is the title that is visible on the template tile in the Create… view.

3

Specify a description for the template. This is the description that is visible on the template tile in the Create… view.

4

Specify the ownership of the template. The owner field provides information about who is responsible for maintaining or overseeing the template within the system or organization. In the provided example, the owner field is set to backstage/techdocs-core. This means that this template belongs to the techdocs-core project in the backstage namespace.

5

Specify the component type. Any string value is accepted for this required field, but your organization should establish a proper taxonomy for these. Red Hat Developer Hub instances may read this field and behave differently depending on its value. For example, a website type component may present tooling in the Red Hat Developer Hub interface that is specific to just websites.

The following values are common for this field:

service: A backend service, typically exposing an API.
website: A website.
library: A software library, such as an npm module or a Java library.

6

Use the parameters section to specify parameters for user input that are shown in a form view when a user creates a component by using the template in the Red Hat Developer Hub console. Each parameters subsection, defined by a title and properties, creates a new form page with that definition.

7

Use the steps section to specify steps that are executed in the backend. These steps must be defined by using a unique step ID, a name, and an action. You can view actions that are available on your Red Hat Developer Hub instance by visiting the URL https://<rhdh_url>/create/actions.

8

Use the output section to specify the structure of output data that is created when the template is used. The output section, particularly the links subsection, provides valuable references and URLs that users can utilize to access and interact with components that are created from the template.

9

Provides a reference or URL to the repository associated with the generated component.

10

Provides a reference or URL that allows users to open the generated component in a catalog or directory where various components are listed.

Additional resources

4.3. Importing an existing template to Red Hat Developer Hub

You can add an existing template to your Red Hat Developer Hub instance by using the Catalog Processor.

Prerequisites

You have created a directory or repository that contains at least one template YAML file.
If you want to use a template that is stored in a repository such as GitHub or GitLab, you must configure a Red Hat Developer Hub integration for your provider.

Procedure

In the app-config.yaml configuration file, modify the catalog.rules section to include a rule for templates, and configure the catalog.locations section to point to the template that you want to add, as shown in the following example:
```
# ...
catalog:
  rules:
    - allow: [Template] 1
  locations:
    - type: url 2
      target: https://<repository_url>/example-template.yaml 3
# ...
```
1
To allow new templates to be added to the catalog, you must add a Template rule.
2
If you are importing templates from a repository, such as GitHub or GitLab, use the url type.
3
Specify the URL for the template.

Verification

Click the Catalog tab in the navigation panel.
In the Kind drop-down menu, select Template.
Confirm that your template is shown in the list of existing templates.

Additional resources

Enabling the GitHub authentication provider

5. Customizing the Learning Paths in Red Hat Developer Hub

In Red Hat Developer Hub, you can configure Learning Paths by passing the data into the app-config.yaml file as a proxy. The base URL must include the /developer-hub/learning-paths proxy.

Note

Due to the use of overlapping pathRewrites for both the learning-path and homepage quick access proxies, you must create the learning-paths configuration (^api/proxy/developer-hub/learning-paths) before you create the homepage configuration (^/api/proxy/developer-hub).

For more information about customizing the Home page in Red Hat Developer Hub, see Customizing the Home page in Red Hat Developer Hub.

You can provide data to the Learning Path from the following sources:

JSON files hosted on GitHub or GitLab.
A dedicated service that provides the Learning Path data in JSON format using an API.

5.1. Using hosted JSON files to provide data to the Learning Paths

Prerequisites

You have installed Red Hat Developer Hub by using either the Operator or Helm chart. For more information, see Installing Red Hat Developer Hub on OpenShift Container Platform.

Procedure

To access the data from the JSON files, complete the following step:

Add the following code to the app-config.yaml file:

proxy:
  endpoints:
    '/developer-hub':
      target: https://raw.githubusercontent.com/
      pathRewrite:
        '^/api/proxy/developer-hub/learning-paths': '/janus-idp/backstage-showcase/main/packages/app/public/learning-paths/data.json'
        '^/api/proxy/developer-hub/tech-radar': '/janus-idp/backstage-showcase/main/packages/app/public/tech-radar/data-default.json'
        '^/api/proxy/developer-hub': '/janus-idp/backstage-showcase/main/packages/app/public/homepage/data.json'
      changeOrigin: true
      secure: true

5.2. Using a dedicated service to provide data to the Learning Paths

When using a dedicated service, you can do the following:

Use the same service to provide the data to all configurable Developer Hub pages or use a different service for each page.
Use the red-hat-developer-hub-customization-provider as an example service, which provides data for both the Home and Tech Radar pages. The red-hat-developer-hub-customization-provider service provides the same data as default Developer Hub data. You can fork the red-hat-developer-hub-customization-provider service repository from GitHub and modify it with your own data, if required.
Deploy the red-hat-developer-hub-customization-provider service and the Developer Hub Helm chart on the same cluster.

Prerequisites

You have installed the Red Hat Developer Hub using Helm chart. For more information, see Installing Red Hat Developer Hub on OpenShift Container Platform.

Procedure

To use a dedicated service to provide the Learning Path data, complete the following steps:

Add the following code to the app-config-rhdh.yaml file:
```
   proxy:
      endpoints:
        # Other Proxies
        '/developer-hub/learning-paths':
          target: ${LEARNING_PATH_DATA_URL}
          changeOrigin: true
          # Change to "false" in case of using self hosted cluster with a self-signed certificate
          secure: true
```
where the LEARNING_PATH_DATA_URL is defined as http://<SERVICE_NAME>/learning-paths, for example, http://rhdh-customization-provider/learning-paths.
Note
You can define the LEARNING_PATH_DATA_URL by adding it to rhdh-secrets or by directly replacing it with its value in your custom ConfigMap.
Delete the Developer Hub pod to ensure that the new configurations are loaded correctly.

6. Configuring TechDocs

Configure the Red Hat Developer Hub TechDocs plugin to create, find, and use documentation in a central location and in a standardized way. For example:

Docs-like-code approach: Write your technical documentation in Markdown files that are stored inside your project repository along with your code.
Documentation site generation: Use MkDocs to create a full-featured, Markdown-based, static HTML site for your documentation that is rendered centrally in Developer Hub.
Documentation site metadata and integrations: See additional metadata about the documentation site alongside the static documentation, such as the date of the last update, the site owner, top contributors, open GitHub issues, Slack support channels, and Stack Overflow Enterprise tags.
Built-in navigation and search: Find the information that you want from a document more quickly and easily.
Add-ons: Customize your TechDocs experience with Add-ons to address higher-order documentation needs.

The TechDocs plugin is preinstalled and enabled on a Developer Hub instance by default. You can disable or enable the TechDocs plugin, and change other parameters, by configuring the Red Hat Developer Hub Helm chart or the Red Hat Developer Hub Operator config map.

Important

Red Hat Developer Hub includes a built-in TechDocs builder that generates static HTML documentation from your codebase. However, the default basic setup of the local builder is not intended for production.

You can use a CI/CD pipeline with the repository that has a dedicated job to generate docs for TechDocs. The generated static files are stored in OpenShift Data Foundation or in a cloud storage solution of your choice and published to a static HTML documentation site.

After you configure OpenShift Data Foundation to store the files that TechDocs generates, you can configure the TechDocs plugin to use the OpenShift Data Foundation for cloud storage.

Additional resources

For more information, see Configuring plugins in Red Hat Developer Hub.

6.1. Configuring storage for TechDocs files

The TechDocs publisher stores generated files in local storage or in cloud storage, such as OpenShift Data Foundation, Google GCS, AWS S3, or Azure Blob Storage.

6.1.1. Using OpenShift Data Foundation for file storage

You can configure OpenShift Data Foundation to store the files that TechDocs generates instead of relying on other cloud storage solutions.

OpenShift Data Foundation provides an ObjectBucketClaim custom resource (CR) that you can use to request an S3 compatible bucket backend. You must install the OpenShift Data Foundation Operator to use this feature.

Prerequisites

An OpenShift Container Platform administrator has installed the OpenShift Data Foundation Operator in Red Hat OpenShift Container Platform. For more information, see OpenShift Container Platform - Installing Red Hat OpenShift Data Foundation Operator.
An OpenShift Container Platform administrator has created an OpenShift Data Foundation cluster and configured the StorageSystem schema. For more information, see OpenShift Container Platform - Creating an OpenShift Data Foundation cluster.

Procedure

Create an ObjectBucketClaim CR where the generated TechDocs files are stored. For example:
```
apiVersion: objectbucket.io/v1alpha1
kind: ObjectBucketClaim
metadata:
  name: <rhdh_bucket_claim_name>
spec:
  generateBucketName: <rhdh_bucket_claim_name>
  storageClassName: openshift-storage.noobaa.io
```
Note
Creating the Developer Hub ObjectBucketClaim CR automatically creates both the Developer Hub ObjectBucketClaim config map and secret. The config map and secret have the same name as the ObjetBucketClaim CR.

After you create the ObjectBucketClaim CR, you can use the information stored in the config map and secret to make the information accessible to the Developer Hub container as environment variables. Depending on the method that you used to install Developer Hub, you add the access information to either the Red Hat Developer Hub Helm chart or Operator configuration.

Additional resources

For more information about the Object Bucket Claim, see OpenShift Container Platform - Object Bucket Claim.

6.1.2. Making object storage accessible to containers by using the Helm chart

Creating a ObjectBucketClaim custom resource (CR) automatically generates both the Developer Hub ObjectBucketClaim config map and secret. The config map and secret contain ObjectBucket access information. Adding the access information to the Helm chart configuration makes it accessible to the Developer Hub container by adding the following environment variables to the container:

BUCKET_NAME
BUCKET_HOST
BUCKET_PORT
BUCKET_REGION
BUCKET_SUBREGION
AWS_ACCESS_KEY_ID
AWS_SECRET_ACCESS_KEY

These variables are then used in the TechDocs plugin configuration.

Prerequisites

You have installed Red Hat Developer Hub on OpenShift Container Platform using the Helm chart.
You have created an ObjectBucketClaim CR for storing files generated by TechDocs. For more information see Using OpenShift Data Foundation for file storage

Procedure

In the upstream.backstage key in the Helm chart values, enter the name of the Developer Hub ObjectBucketClaim secret as the value for the extraEnvVarsSecrets field and the extraEnvVarsCM field. For example:
```
upstream:
  backstage:
    extraEnvVarsSecrets:
      - <rhdh_bucket_claim_name>
    extraEnvVarsCM:
      - <rhdh_bucket_claim_name>
```

6.1.2.1. Example TechDocs Plugin configuration for the Helm chart

The following example shows a Developer Hub Helm chart configuration for the TechDocs plugin:

global:
  dynamic:
    includes:
      - 'dynamic-plugins.default.yaml'
  plugins:
    - disabled: false
      package: ./dynamic-plugins/dist/backstage-plugin-techdocs-backend-dynamic
      pluginConfig:
        techdocs:
          builder: external
          generator:
            runIn: local
          publisher:
            awsS3:
              bucketName: '${BUCKET_NAME}'
              credentials:
                accessKeyId: '${AWS_ACCESS_KEY_ID}'
                secretAccessKey: '${AWS_SECRET_ACCESS_KEY}'
              endpoint: 'https://${BUCKET_HOST}'
              region: '${BUCKET_REGION}'
              s3ForcePathStyle: true
            type: awsS3

6.1.3. Making object storage accessible to containers by using the Operator

Creating a ObjectBucketClaim Custom Resource (CR) automatically generates both the Developer Hub ObjectBucketClaim config map and secret. The config map and secret contain ObjectBucket access information. Adding the access information to the Operator configuration makes it accessible to the Developer Hub container by adding the following environment variables to the container:

BUCKET_NAME
BUCKET_HOST
BUCKET_PORT
BUCKET_REGION
BUCKET_SUBREGION
AWS_ACCESS_KEY_ID
AWS_SECRET_ACCESS_KEY

These variables are then used in the TechDocs plugin configuration.

Prerequisites

You have installed Red Hat Developer Hub on OpenShift Container Platform using the Operator.
You have created an ObjectBucketClaim CR for storing files generated by TechDocs.

Procedure

In the Developer Hub Backstage CR, enter the name of the Developer Hub ObjectBucketClaim config map as the value for the spec.application.extraEnvs.configMaps field and enter the Developer Hub ObjectBucketClaim secret name as the value for the spec.application.extraEnvs.secrets field. For example:
```
apiVersion: objectbucket.io/v1alpha1
kind: Backstage
metadata:
 name: <name>
spec:
  application:
    extraEnvs:
      configMaps:
        - name: <rhdh_bucket_claim_name>
      secrets:
        - name: <rhdh_bucket_claim_name>
```

6.1.3.1. Example TechDocs Plugin configuration for the Operator

The following example shows a Red Hat Developer Hub Operator config map configuration for the TechDocs plugin:

kind: ConfigMap
apiVersion: v1
metadata:
  name: dynamic-plugins-rhdh
data:
  dynamic-plugins.yaml: |
    includes:
      - dynamic-plugins.default.yaml
    plugins:
      - disabled: false
        package: ./dynamic-plugins/dist/backstage-plugin-techdocs-backend-dynamic
        pluginConfig:
          techdocs:
            builder: external
            generator:
              runIn: local
            publisher:
              awsS3:
                bucketName: '${BUCKET_NAME}'
                credentials:
                  accessKeyId: '${AWS_ACCESS_KEY_ID}'
                  secretAccessKey: '${AWS_SECRET_ACCESS_KEY}'
                endpoint: 'https://${BUCKET_HOST}'
                region: '${BUCKET_REGION}'
                s3ForcePathStyle: true
              type: awsS3

6.2. Configuring CI/CD to generate and publish TechDocs sites

TechDocs reads the static generated documentation files from a cloud storage bucket, such as OpenShift Data Foundation. The documentation site is generated on the CI/CD workflow associated with the repository containing the documentation files. You can generate docs on CI and publish to a cloud storage using the techdocs-cli CLI tool.

You can use the following example to create a script for TechDocs publication:

# Prepare
REPOSITORY_URL='https://github.com/org/repo'
git clone $REPOSITORY_URL
cd repo

# Install @techdocs/cli, mkdocs and mkdocs plugins
npm install -g @techdocs/cli
pip install "mkdocs-techdocs-core==1.*"

# Generate
techdocs-cli generate --no-docker

# Publish
techdocs-cli publish --publisher-type awsS3 --storage-name <bucket/container> --entity <Namespace/Kind/Name>

The TechDocs workflow starts the CI when a user makes changes in the repository containing the documentation files. You can configure the workflow to start only when files inside the docs/ directory or mkdocs.yml are changed.

6.2.1. Preparing your repository for CI

The first step on the CI is to clone your documentation source repository in a working directory.

Procedure

To clone your documentation source repository in a working directory, enter the following command:
```
git clone <https://path/to/docs-repository/>
```

6.2.2. Generating the TechDocs site

Procedure

To configure CI/CD to generate your techdocs, complete the following steps:

Install the npx package to run techdocs-cli using the following command:
```
npm install -g npx
```
Install the techdocs-cli tool using the following command:
```
npm install -g @techdocs/cli
```
Install the mkdocs plugins using the following command:
```
pip install "mkdocs-techdocs-core==1.*"
```
Generate your techdocs site using the following command:
```
npx @techdocs/cli generate --no-docker --source-dir <path_to_repo> --output-dir ./site
```
Where <path_to_repo> is the location in the file path that you used to clone your repository.

6.2.3. Publishing the TechDocs site

Procedure

To publish your techdocs site, complete the following steps:

Set the necessary authentication environment variables for your cloud storage provider.

Publish your techdocs using the following command:

npx @techdocs/cli publish --publisher-type <awsS3|googleGcs> --storage-name <bucket/container> --entity <namespace/kind/name> --directory ./site

Add a .github/workflows/techdocs.yml file in your Software Template(s). For example:

name: Publish TechDocs Site

on:
 push:
   branches: [main]
   # You can even set it to run only when TechDocs related files are updated.
   # paths:
   #   - "docs/**"
   #   - "mkdocs.yml"

jobs:
 publish-techdocs-site:
   runs-on: ubuntu-latest

   # The following secrets are required in your CI environment for publishing files to AWS S3.
   # e.g. You can use GitHub Organization secrets to set them for all existing and new repositories.
   env:
     TECHDOCS_S3_BUCKET_NAME: ${{ secrets.TECHDOCS_S3_BUCKET_NAME }}
     AWS_ACCESS_KEY_ID: ${{ secrets.AWS_ACCESS_KEY_ID }}
     AWS_SECRET_ACCESS_KEY: ${{ secrets.AWS_SECRET_ACCESS_KEY }}
     AWS_REGION: ${{ secrets.AWS_REGION }}
     ENTITY_NAMESPACE: 'default'
     ENTITY_KIND: 'Component'
     ENTITY_NAME: 'my-doc-entity'
     # In a Software template, Scaffolder will replace {{cookiecutter.component_id | jsonify}}
     # with the correct entity name. This is same as metadata.name in the entity's catalog-info.yaml
     # ENTITY_NAME: '{{ cookiecutter.component_id | jsonify }}'

   steps:
     - name: Checkout code
       uses: actions/checkout@v3

     - uses: actions/setup-node@v3
     - uses: actions/setup-python@v4
       with:
         python-version: '3.9'

     - name: Install techdocs-cli
       run: sudo npm install -g @techdocs/cli

     - name: Install mkdocs and mkdocs plugins
       run: python -m pip install mkdocs-techdocs-core==1.*

     - name: Generate docs site
       run: techdocs-cli generate --no-docker --verbose

     - name: Publish docs site
       run: techdocs-cli publish --publisher-type awsS3 --storage-name $TECHDOCS_S3_BUCKET_NAME --entity $ENTITY_NAMESPACE/$ENTITY_KIND/$ENTITY_NAME

7. Customizing the Tech Radar page in Red Hat Developer Hub

In Red Hat Developer Hub, the Tech Radar page is provided by the tech-radar dynamic plugin, which is disabled by default. For information about enabling dynamic plugins in Red Hat Developer Hub see Configuring plugins in Red Hat Developer Hub.

In Red Hat Developer Hub, you can configure Learning Paths by passing the data into the app-config.yaml file as a proxy. The base Tech Radar URL must include the /developer-hub/tech-radar proxy.

Note

Due to the use of overlapping pathRewrites for both the tech-radar and homepage quick access proxies, you must create the tech-radar configuration (^api/proxy/developer-hub/tech-radar) before you create the homepage configuration (^/api/proxy/developer-hub).

For more information about customizing the Home page in Red Hat Developer Hub, see Customizing the Home page in Red Hat Developer Hub.

You can provide data to the Tech Radar page from the following sources:

JSON files hosted on GitHub or GitLab.
A dedicated service that provides the Tech Radar data in JSON format using an API.

7.1. Using hosted JSON files to provide data to the Tech Radar page

Prerequisites

You have installed Red Hat Developer Hub by using either the Operator or Helm chart. For more information, see Installing Red Hat Developer Hub on OpenShift Container Platform.
You have specified the data sources for the Tech Radar plugin in the integrations section of the app-config.yaml file. For example, to configure GitHub as an integration, see Authenticating with GitHub.

Procedure

To access the data from the JSON files, complete the following step:

Enable the ./dynamic-plugins/dist/backstage-community-plugin-tech-radar and /dynamic-plugins/dist/backstage-community-plugin-tech-radar-backend-dynamic plugins.
Add the following code to the app-config.yaml file:
```
techRadar:
    url: ${TECH_RADAR_DATA_URL} 1
```
1
TECH_RADAR_DATA_URL is the URL from which the JSON data is loaded.

7.2. Using a dedicated service to provide data to the Tech Radar page

When using a dedicated service, you can do the following:

Use the same service to provide the data to all configurable Developer Hub pages or use a different service for each page.
Use the red-hat-developer-hub-customization-provider as an example service, which provides data for both the Home and Tech Radar pages. The red-hat-developer-hub-customization-provider service provides the same data as default Developer Hub data. You can fork the red-hat-developer-hub-customization-provider service repository from GitHub and modify it with your own data, if required.
Deploy the red-hat-developer-hub-customization-provider service and the Developer Hub Helm chart on the same cluster.

Prerequisites

You have installed the Red Hat Developer Hub using Helm Chart. For more information, see Installing Red Hat Developer Hub on OpenShift Container Platform with the Helm chart.

Procedure

To use a separate service to provide the Tech Radar data, complete the following steps:

Add the dedicated service as an allowed host by adding the following code to the app-config.yaml file:
```
backend:
   reading:
        allow:
          - host: 'hostname'
```
Add the following to the app-config.yaml file:
```
techRadar:
    url: ${TECH_RADAR_DATA_URL} 1
```
1
TECH_RADAR_DATA_URL is the URL from which the JSON data is loaded.

8. Customizing Red Hat Developer Hub appearance

The following default theme configurations are available for Red Hat Developer Hub:

The Red Hat Developer Hub theme: Default theme configurations to make your developer portal look like a standard Red Hat Developer Hub instance. For more information, see Section 8.7, “Default Red Hat Developer Hub theme”
The Backstage theme: Default theme configurations to make your developer portal look like a standard Backstage instance. For more information, see Section 8.8, “Default Backstage theme”

You can change or disable particular parameters in a default theme or create a fully customized theme by modifying the app-config-rhdh.yaml file. From the app-config-rhdh.yaml file, you can customize common theme components, including the following:

Company name and logo
Font color, size, and style of text in paragraphs, headings, headers, and buttons
Header color, gradient, and shape
Button color
Navigation indicator color

You can also customize some components from the Developer Hub GUI, such as the theme mode (Light Theme, Dark Theme, or Auto).

8.1. Customizing the theme mode for your Developer Hub instance

Note

In Developer Hub, theme configurations are used to change the look and feel of different UI components. So, you might notice changes in different UI components, such as buttons, tabs, sidebars, cards, and tables along with some changes in background color and font used on the RHDH pages.

You can choose one of the following theme modes for your Developer Hub instance:

Light theme
Dark theme
Auto

The default theme mode is Auto, which automatically sets the light or dark theme based on your system preferences.

Prerequisites

You are logged in to the Developer Hub web console.

Procedure

From the Developer Hub web console, click Settings.
From the Appearance panel, click LIGHT THEME, DARK THEME, or AUTO to change the theme mode.

8.2. Customizing the branding logo of your Developer Hub instance

You can customize the branding logo of your Developer Hub instance by configuring the branding section the app-config-rhdh.yaml file, as shown in the following example:

app:
  branding:
    fullLogo: ${BASE64_EMBEDDED_FULL_LOGO} 1
    iconLogo: ${BASE64_EMBEDDED_ICON_LOGO} 2

where:

1: fullLogo is the logo on the expanded (pinned) sidebar and expects a base64 encoded image.
2: iconLogo is the logo on the collapsed (unpinned) sidebar and expects a base64 encoded image.

You can also customize the width of the branding logo by setting a value for the fullLogoWidth field in the branding section, as shown in the following example:

app:
  branding:
    fullLogoWidth: 110px 1
# ...

1: The default value for the logo width is 110px. The following units are supported: integer, px, em, rem, percentage.

8.3. Customizing the sidebar menu items for your Developer Hub instance

The sidebar menu in Red Hat Developer Hub consists of two main parts:

Main menu items: These items are the static menu items that form the core navigation structure of sidebar. These menu items remain consistent and are predefined.
Dynamic plugin menu items: These items are displayed beneath the main menu and can be customized based on the plugins installed. The main menu items section is dynamic and can change based on your preferences and installed plugins.

Procedure

Customize the main menu items using the following steps:
1. Open the app-config-rhdh.yaml file.
2. To customize the order and parent-child relationships for the main menu items, use the dynamicPlugins.frontend.default.main-menu-items.menuItems field.
3. For dynamic plugin menu items, use the dynamicPlugins.frontend.<package_name>.menuItems field.
Example app-config-rhdh.yaml file
```
dynamicPlugins:
  frontend:
    <package_name>: # same as `scalprum.name` key in plugin's `package.json`
      menuItems: # optional, allows you to configure plugin menu items in the main sidebar navigation
        <menu_item_name>: # unique name in the plugin menu items list 1
          icon: home | group | category | extension | school | _<your_icon>_  2
          title: My Plugin Page # optional, same as `menuItem.text` in `dynamicRoutes` 3
          priority: 10 # optional, defines the order of menu items in the sidebar 4
          parent: favorites # optional, defines parent-child relationships for nested menu items 5
```
You can modify the fields in the previous example to configure the desired order and parent-child relationships of the sidebar menu items.
1
This attribute represents a unique name in the main sidebar navigation. It can denote either a standalone menu item or a parent menu item. If this attribute represents a plugin menu item, the name of the attribute must match with the corresponding path in dynamicRoutes. For example, if dynamicRoutes defines path: /my-plugin, then menu_item_name must be defined as my-plugin.
For more complex, multi-segment paths such as path: /metrics/users/info, the menu_item_name must use dot notation to represent the full path, for example, metrics.users.info. Trailing and leading slashes in paths are ignored. For example, path: /docs results in menu_item_name: docs, and path: /metrics/users results in menu_item_name: metrics.users.
2
This optional attribute specifies the icon for the menu item. You can use default icons or extend the icon set with dynamic plugins. Developer Hub also provides additional icons in its internal library, such as:
Home Icon in the internal library

dynamicPlugins: frontend: <package_name>: menuItems: <menu_item_name>: icon: home
Similarly, the internal library includes icons for group, category, extension, and school. If the icon is already defined in the dynamicRoutes configuration under menuItem.icon, it can be removed from the in the menuItems configuration. Also, both SVG and HTML image icons are supported. For example:
Example SVG icon

icon: <svg width="20px" height="20px" viewBox="0 0 512 512" xmlns="http://www.w3.org/2000/svg" fill="#ffffff">...</svg>
Example image icon

icon: https://img.icons8.com/ios-glyphs/20/FFFFFF/shop.png
3
This optional attribute specifies the title of the menu item. It can be removed if the title is already specified in the dynamicRoutes configuration under menuItem.text.
4
This optional attribute sets the order in which menu items appear in the sidebar. The default priority is 0, which places the item at the bottom of the list. A higher priority value places the item higher in the sidebar. You can define this attribute for each section.
5
This optional attribute specifies the parent menu item under which the current item is nested. If this attribute is used, the parent menu item must be defined elsewhere in the menuItems configuration of any enabled plugin. You can define this attribute for each section.
Example menuItems configuration
```
dynamicPlugins:
  frontend:
    <package_name>:
      dynamicRoutes:
        - path: /my-plugin
          module: CustomModule
          importName: FooPluginPage
          menuItem:
            icon: fooIcon
            text: Foo Plugin Page
      menuItems:
        my-plugin: # matches `path` in `dynamicRoutes`
          priority: 10 # controls order of plugins under the parent menu item
          parent: favorites # nests this plugin under the `favorites` parent menu item
        favorites: # configuration for the parent menu item
          icon: favorite # icon from RHDH system icons
          title: Favorites # title for the parent menu item
          priority: 100 # controls the order of this top-level menu item
```

To ensure that a menu item is identified as a main menu item, you must add the default. prefix to its key. For example:

Example configuration of main menu items in sidebar navigation

dynamicPlugins:
  frontend:
    default.main-menu-items: # key for configuring static main menu items
      menuItems:
        default.<menu_item_name>: # key of the menu item configuration. `default.` prefix is required for a main menu item key 1
          parent: my_menu_group # optional, specifies the parent menu item for this item
          priority: 10 # optional, specifies the order of this menu item within its menu level
        default.<menu_group_parent_item_name>: # must be configured if it is specified as the parent of any menu items. `default.` prefix is required for a main group parent item key 2
          icon: my_menu_group_icon # required for parent menu items, defines the icon for the menu group
          title: my_menu_group_title # required for parent menu items, defines the icon for the menu group
          priority: 100 # optional, specifies the order of the parent menu item in the sidebar

1 2: The default. prefix identifes an item as a main menu item. You can add the default. prefix to both individual menu items or parent menu group configuration, such as default.<menu_group_parent_item_name> in the previous example.

Note

The default priority of main menu items determines their order in the sidebar. You can customize the order of the static main menu items by adjusting their priority values. Ensure that the priority and title of each item is clear to facilitate easy reordering.

8.4. Customizing the theme mode color palettes for your Developer Hub instance

You can customize the color palettes of the light and dark theme modes in your Developer Hub instance by configuring the light.palette and dark.palette parameters in the branding.theme section of the app-config-rhdh.yaml file, as shown in the following example:

app:
  branding:
    theme:
      light:
        palette:
          primary:
            main: <light_primary_color> 1
          navigation:
            indicator: <light_indicator_color> 2
        pageTheme:
          default:
            backgroundColor: [<light_background_color_1>, <light_background_color_2>] 3
      dark:
        palette:
          primary:
            main: <dark_primary_color> 4
          navigation:
            indicator: <dark_indicator_color> 5
        pageTheme:
          default:
            backgroundColor: [<dark_background_color_1>, <dark_background_color_2>] 6
# ...

1: The main primary color for the light color palette, for example, #ffffff or white
2: The color of the navigation indicator for the light color palette, which is a vertical bar that indicates the selected tab in the navigation panel, for example, #FF0000 or red
3: The background color for the default page theme for the light color palette, for example, #ffffff or white
4: The main primary color for the dark color palette, for example, #000000 or black
5: The color of the navigation indicator for the dark color palette, which is a vertical bar that indicates the selected tab in the navigation panel, for example, #FF0000 or red
6: The background color for the default page theme for the dark color palette, for example, #000000 or black

Additional resources

Section 8.1, “Customizing the theme mode for your Developer Hub instance”

8.5. Customizing the page theme header for your Developer Hub instance

You can customize the header color for the light and dark theme modes in your Developer Hub instance by modifying the branding.theme section of the app-config-rhdh.yaml file. You can also customize the page headers for additional Developer Hub pages, such as the Home, Catalog, and APIs pages.

app:
  branding:
    theme:
      light: 1
        palette: {}
        pageTheme:
          default: 2
            backgroundColor: "<default_light_background_color>" 3
            fontColor: "<default_light_font_color>" 4
            shape: none 5
          apis: 6
            backgroundColor: "<apis_light_background_color>"
            fontColor: "<apis_light_font_color>"
            shape: none
      dark:
        palette: {}
        pageTheme:
          default:
            backgroundColor: "<default_dark_background_color>"
            fontColor: "<default_dark_font_color>"
            shape: none
# ...

1: The theme mode, for example, light or dark
2: The yaml header for the default page theme configuration
3: The color of the page header background, for example, #ffffff or white
4: The color of the text in the page header, for example, #000000 or black
5: The pattern on the page header, for example, wave, round, or none
6: The yaml header for a specific page theme configuration, for example, apis, home

8.6. Customizing the font for your Developer Hub instance

You can configure the typography section of the app-config-rhdh.yaml file to change the default font family and size of the page text, as well as the font family and size of each heading level, as shown in the following example:

app:
  branding:
    theme:
      light:
        typography:
          fontFamily: "Times New Roman"
          htmlFontSize: 11 # smaller is bigger
          h1:
            fontFamily: "Times New Roman"
            fontSize: 40
          h2:
            fontFamily: "Times New Roman"
            fontSize: 30
          h3:
            fontFamily: "Times New Roman"
            fontSize: 30
          h4:
            fontFamily: "Times New Roman"
            fontSize: 30
          h5:
            fontFamily: "Times New Roman"
            fontSize: 30
          h6:
            fontFamily: "Times New Roman"
            fontSize: 30
      dark:
        typography:
          fontFamily: "Times New Roman"
          htmlFontSize: 11 # smaller is bigger
          h1:
            fontFamily: "Times New Roman"
            fontSize: 40
          h2:
            fontFamily: "Times New Roman"
            fontSize: 30
          h3:
            fontFamily: "Times New Roman"
            fontSize: 30
          h4:
            fontFamily: "Times New Roman"
            fontSize: 30
          h5:
            fontFamily: "Times New Roman"
            fontSize: 30
          h6:
            fontFamily: "Times New Roman"
            fontSize: 30
# ...

8.7. Default Red Hat Developer Hub theme

You can use the default Red Hat Developer Hub theme configurations to make your Developer Hub instance look like a standard Red Hat Developer Hub instance. You can also modify the app-config-rhdh.yaml file to customize or disable particular parameters.

8.7.1. Default Red Hat Developer Hub theme color palette

The app-config-rhdh.yaml file uses the following configurations for the default Red Hat Developer Hub color palette:

app:
  branding:
    theme:
      light:
        variant: "rhdh"
        mode: "light"
        palette:
          background:
            default: "#F8F8F8"
            paper: "#FFFFFF"
          banner:
            closeButtonColor: "#FFFFFF"
            error: "#E22134"
            info: "#2E77D0"
            link: "#000000"
            text: "#FFFFFF"
            warning: "#FF9800"
          border: "#E6E6E6"
          bursts:
            backgroundColor:
              default: "#7C3699"
            fontColor: "#FEFEFE"
            gradient:
              linear: "linear-gradient(-137deg, #4BB8A5 0%, #187656 100%)"
            slackChannelText: "#ddd"
          errorBackground: "#FFEBEE"
          errorText: "#CA001B"
          gold: "#FFD600"
          highlight: "#FFFBCC"
          infoBackground: "#ebf5ff"
          infoText: "#004e8a"
          link: "#0A6EBE"
          linkHover: "#2196F3"
          mode: "light"
          navigation:
            background: "#222427"
            indicator: "#0066CC"
            color: "#ffffff"
            selectedColor: "#ffffff"
            navItem:
              hoverBackground: "#3c3f42"
            submenu:
              background: "#222427"
          pinSidebarButton:
            background: "#BDBDBD"
            icon: "#181818"
          primary:
            main: "#0066CC"
          secondary:
            main: "#8476D1"
          status:
            aborted: "#757575"
            error: "#E22134"
            ok: "#1DB954"
            pending: "#FFED51"
            running: "#1F5493"
            warning: "#FF9800"
          tabbar:
            indicator: "#9BF0E1"
          textContrast: "#000000"
          textSubtle: "#6E6E6E"
          textVerySubtle: "#DDD"
          warningBackground: "#F59B23"
          warningText: "#000000"
          text:
            primary: "#151515"
            secondary: "#757575"
          rhdh:
            general:
              disabledBackground: "#D2D2D2"
              disabled: "#6A6E73"
              searchBarBorderColor: "#E4E4E4"
              formControlBackgroundColor: "#FFF"
              mainSectionBackgroundColor: "#FFF"
              headerBottomBorderColor: "#C7C7C7"
              cardBackgroundColor: "#FFF"
              sideBarBackgroundColor: "#212427"
              cardBorderColor: "#C7C7C7"
              tableTitleColor: "#181818"
              tableSubtitleColor: "#616161"
              tableColumnTitleColor: "#151515"
              tableRowHover: "#F5F5F5"
              tableBorderColor: "#E0E0E0"
              tableBackgroundColor: "#FFF"
              tabsBottomBorderColor: "#D2D2D2"
              contrastText: "#FFF"
            primary:
              main: "#0066CC"
              focusVisibleBorder: "#0066CC"
            secondary:
              main: "#8476D1"
              focusVisibleBorder: "#8476D1"
            cards:
              headerTextColor: "#151515"
              headerBackgroundColor: "#FFF"
              headerBackgroundImage: "none"

      dark:
        variant: "rhdh"
        mode: "dark"
        palette:
          background:
            default: "#333333"
            paper: "#424242"
          banner:
            closeButtonColor: "#FFFFFF"
            error: "#E22134"
            info: "#2E77D0"
            link: "#000000"
            text: "#FFFFFF"
            warning: "#FF9800"
          border: "#E6E6E6"
          bursts:
            backgroundColor:
              default: "#7C3699"
            fontColor: "#FEFEFE"
            gradient:
              linear: "linear-gradient(-137deg, #4BB8A5 0%, #187656 100%)"
            slackChannelText: "#ddd"
          errorBackground: "#FFEBEE"
          errorText: "#CA001B"
          gold: "#FFD600"
          highlight: "#FFFBCC"
          infoBackground: "#ebf5ff"
          infoText: "#004e8a"
          link: "#9CC9FF"
          linkHover: "#82BAFD"
          mode: "dark"
          navigation:
            background: "#0f1214"
            indicator: "#0066CC"
            color: "#ffffff"
            selectedColor: "#ffffff"
            navItem:
              hoverBackground: "#3c3f42"
            submenu:
              background: "#0f1214"
          pinSidebarButton:
            background: "#BDBDBD"
            icon: "#404040"
          primary:
            main: "#1FA7F8"
          secondary:
            main: "#B2A3FF"
          status:
            aborted: "#9E9E9E"
            error: "#F84C55"
            ok: "#71CF88"
            pending: "#FEF071"
            running: "#3488E3"
            warning: "#FFB84D"
          tabbar:
            indicator: "#9BF0E1"
          textContrast: "#FFFFFF"
          textSubtle: "#CCCCCC"
          textVerySubtle: "#727272"
          warningBackground: "#F59B23"
          warningText: "#000000"

          rhdh:
            general:
              disabledBackground: "#444548"
              disabled: "#AAABAC"
              searchBarBorderColor: "#57585a"
              formControlBackgroundColor: "#36373A"
              mainSectionBackgroundColor: "#0f1214"
              headerBottomBorderColor: "#A3A3A3"
              cardBackgroundColor: "#292929"
              sideBarBackgroundColor: "#1b1d21"
              cardBorderColor: "#A3A3A3"
              tableTitleColor: "#E0E0E0"
              tableSubtitleColor: "#E0E0E0"
              tableColumnTitleColor: "#E0E0E0"
              tableRowHover: "#0f1214"
              tableBorderColor: "#515151"
              tableBackgroundColor: "#1b1d21"
              tabsBottomBorderColor: "#444548"
              contrastText: "#FFF"
            primary:
              main: "#1FA7F8"
              focusVisibleBorder: "#ADD6FF"
            secondary:
              main: "#B2A3FF"
              focusVisibleBorder: "#D0C7FF"
            cards:
              headerTextColor: "#FFF"
              headerBackgroundColor: "#0f1214"
              headerBackgroundImage: "none"

Alternatively, you can use the following variant and mode values in the app-config-rhdh.yaml file to apply the previous default configuration:

app:
  branding:
    theme:
      light:
        variant: "rhdh"
        mode: "light"
      dark:
        variant: "rhdh"
        mode: "dark"

8.7.2. Default Red Hat Developer Hub page themes

The default Developer Hub header color is white in light mode and black in dark mode, as shown in the following app-config-rhdh.yaml file configuration:

app:
  branding:
    theme:
      light:
        palette: {}
        defaultPageTheme: default
        pageTheme:
          default:
            backgroundColor: "#ffffff"
      dark:
        palette: {}
        defaultPageTheme: default
        pageTheme:
          default:
            backgroundColor: "#0f1214"

8.8. Default Backstage theme

You can use the default Backstage theme configurations to make your Developer Hub instance look like a standard Backstage instance. You can also modify the app-config-rhdh.yaml file to customize or disable particular parameters.

8.8.1. Default Backstage theme color palette

The app-config-rhdh.yaml file uses the following configurations for the default Backstage color palette:

app:
  branding:
    theme:
      light:
        variant: "backstage"
        mode: "light"
        palette:
          background:
            default: "#F8F8F8"
            paper: "#FFFFFF"
          banner:
            closeButtonColor: "#FFFFFF"
            error: "#E22134"
            info: "#2E77D0"
            link: "#000000"
            text: "#FFFFFF"
            warning: "#FF9800"
          border: "#E6E6E6"
          bursts:
            backgroundColor:
              default: "#7C3699"
            fontColor: "#FEFEFE"
            gradient:
              linear: "linear-gradient(-137deg, #4BB8A5 0%, #187656 100%)"
            slackChannelText: "#ddd"
          errorBackground: "#FFEBEE"
          errorText: "#CA001B"
          gold: "#FFD600"
          highlight: "#FFFBCC"
          infoBackground: "#ebf5ff"
          infoText: "#004e8a"
          link: "#0A6EBE"
          linkHover: "#2196F3"
          navigation:
            background: "#171717"
            color: "#b5b5b5"
            indicator: "#9BF0E1"
            navItem:
              hoverBackground: "#404040"
            selectedColor: "#FFF"
            submenu:
              background: "#404040"
          pinSidebarButton:
            background: "#BDBDBD"
            icon: "#181818"
          primary:
            main: "#1F5493"
          status:
            aborted: "#757575"
            error: "#E22134"
            ok: "#1DB954"
            pending: "#FFED51"
            running: "#1F5493"
            warning: "#FF9800"
          tabbar:
            indicator: "#9BF0E1"
          textContrast: "#000000"
          textSubtle: "#6E6E6E"
          textVerySubtle: "#DDD"
          warningBackground: "#F59B23"
          warningText: "#000000"

      dark:
        variant: "backstage"
        mode: "dark"
        palette:
          background:
            default: "#333333"
            paper: "#424242"
          banner:
            closeButtonColor: "#FFFFFF"
            error: "#E22134"
            info: "#2E77D0"
            link: "#000000"
            text: "#FFFFFF"
            warning: "#FF9800"
          border: "#E6E6E6"
          bursts:
            backgroundColor:
              default: "#7C3699"
            fontColor: "#FEFEFE"
            gradient:
              linear: "linear-gradient(-137deg, #4BB8A5 0%, #187656 100%)"
            slackChannelText: "#ddd"
          errorBackground: "#FFEBEE"
          errorText: "#CA001B"
          gold: "#FFD600"
          highlight: "#FFFBCC"
          infoBackground: "#ebf5ff"
          infoText: "#004e8a"
          link: "#9CC9FF"
          linkHover: "#82BAFD"
          mode: "dark"
          navigation:
            background: "#424242"
            color: "#b5b5b5"
            indicator: "#9BF0E1"
            navItem:
              hoverBackground: "#404040"
            selectedColor: "#FFF"
            submenu:
              background: "#404040"
          pinSidebarButton:
            background: "#BDBDBD"
            icon: "#404040"
          primary:
            dark: "#82BAFD"
            main: "#9CC9FF"
          secondary:
            main: "#FF88B2"
          status:
            aborted: "#9E9E9E"
            error: "#F84C55"
            ok: "#71CF88"
            pending: "#FEF071"
            running: "#3488E3"
            warning: "#FFB84D"
          tabbar:
            indicator: "#9BF0E1"
          textContrast: "#FFFFFF"
          textSubtle: "#CCCCCC"
          textVerySubtle: "#727272"
          warningBackground: "#F59B23"
          warningText: "#000000"

Alternatively, you can use the following variant and mode values in the app-config-rhdh.yaml file to apply the previous default configuration:

app:
  branding:
    theme:
      light:
        variant: "backstage"
        mode: "light"
      dark:
        variant: "backstage"
        mode: "dark"

8.8.2. Default Backstage page themes

The default Backstage header color is white in light mode and black in dark mode, as shown in the following app-config-rhdh.yaml file configuration:

app:
  branding:
    theme:
      light:
        palette: {}
        defaultPageTheme: default
        pageTheme:
          default:
            backgroundColor: ['#005B4B'] # teal
            fontColor: '#ffffff'
            shape: wave
          documentation:
            backgroundColor: ['#C8077A', '#C2297D'] # pinkSea
            fontColor: '#ffffff'
            shape: wave2
          tool:
            backgroundColor: ['#8912CA', '#3E00EA'] # purpleSky
            fontColor: '#ffffff'
            shape: round
          service:
            backgroundColor: ['#006D8F', '#0049A1'] # marineBlue
            fontColor: '#ffffff'
            shape: wave
          website:
            backgroundColor: ['#0027AF', '#270094'] # veryBlue
            fontColor: '#ffffff'
            shape: wave
          library:
            backgroundColor: ['#98002B', '#8D1134'] # rubyRed
            fontColor: '#ffffff'
            shape: wave
          other:
            backgroundColor: ['#171717', '#383838'] # darkGrey
            fontColor: '#ffffff'
            shape: wave
          app:
            backgroundColor: ['#BE2200', '#A41D00'] # toastyOrange
            fontColor: '#ffffff'
            shape: shapes.wave
          apis:
            backgroundColor: ['#005B4B'] # teal
            fontColor: '#ffffff'
            shape: wave2
          card:
            backgroundColor: ['#4BB8A5', '#187656'] # greens
            fontColor: '#ffffff'
            shape: wave

      dark:
        palette: {}
        defaultPageTheme: default
        pageTheme:
          default:
            backgroundColor: ['#005B4B'] # teal
            fontColor: '#ffffff'
            shape: wave
          documentation:
            backgroundColor: ['#C8077A', '#C2297D'] # pinkSea
            fontColor: '#ffffff'
            shape: wave2
          tool:
            backgroundColor: ['#8912CA', '#3E00EA'] # purpleSky
            fontColor: '#ffffff'
            shape: round
          service:
            backgroundColor: ['#006D8F', '#0049A1'] # marineBlue
            fontColor: '#ffffff'
            shape: wave
          website:
            backgroundColor: ['#0027AF', '#270094'] # veryBlue
            fontColor: '#ffffff'
            shape: wave
          library:
            backgroundColor: ['#98002B', '#8D1134'] # rubyRed
            fontColor: '#ffffff'
            shape: wave
          other:
            backgroundColor: ['#171717', '#383838'] # darkGrey
            fontColor: '#ffffff'
            shape: wave
          app:
            backgroundColor: ['#BE2200', '#A41D00'] # toastyOrange
            fontColor: '#ffffff'
            shape: shapes.wave
          apis:
            backgroundColor: ['#005B4B'] # teal
            fontColor: '#ffffff'
            shape: wave2
          card:
            backgroundColor: ['#4BB8A5', '#187656'] # greens
            fontColor: '#ffffff'
            shape: wave

8.9. Loading a custom Developer Hub theme by using a dynamic plugin

You can load a custom Developer Hub theme from a dynamic plugin.

Procedure

Export a theme provider function in your dynamic plugin, for example:

Sample myTheme.ts fragment

import { lightTheme } from './lightTheme'; // some custom theme
import { UnifiedThemeProvider } from '@backstage/theme';
export const lightThemeProvider = ({ children }: { children: ReactNode }) => (
  <UnifiedThemeProvider theme={lightTheme} children={children} />
);

For more information about creating a custom theme, see Backstage documentation - Creating a Custom Theme.

Configure Developer Hub to load the theme in the UI by using the themes configuration field:
app-config-rhdh.yaml fragment
```
dynamicPlugins:
  frontend:
    example.my-custom-theme-plugin:
      themes:
        - id: light 1
          title: Light
          variant: light
          icon: someIconReference
          importName: lightThemeProvider
```
1
Set your theme ID by specifying the desired value. Optionally, override the default Developer Hub themes by using the following ID values: light to replace the default light theme, or dark to replace the default dark theme.

Verification

The theme is available in the Developer Hub Settings page.

8.10. Custom component options for your Developer Hub instance

There are two component variants that you can use to customize various components of your Developer Hub theme:

Patternfly
MUI

In addition to assigning a component variant to each parameter in the light or dark theme mode configurations, you can toggle the rippleEffect on or off.

The following code shows the options that you can use in the app-config-rhdh.yaml file to configure the theme components for your Developer Hub instance:

app:
  branding:
    theme:
      light:
        options:
          rippleEffect: off / on
          paper: patternfly / mui
          buttons: patternfly / mui
          inputs: patternfly / mui
          accordions: patternfly / mui
          sidebars: patternfly / mui
          pages: patternfly / mui
          headers: patternfly / mui
          toolbars: patternfly / mui
          dialogs: patternfly / mui
          cards: patternfly / mui
          tables: patternfly / mui
          tabs: patternfly / mui
      dark:
        options:
          rippleEffect: off / on
          paper: patternfly / mui
          buttons: patternfly / mui
          inputs: patternfly / mui
          accordions: patternfly / mui
          sidebars: patternfly / mui
          pages: patternfly / mui
          headers: patternfly / mui
          toolbars: patternfly / mui
          dialogs: patternfly / mui
          cards: patternfly / mui
          tables: patternfly / mui
          tabs: patternfly / mui

9. Customizing the Home page

When using the app-config, you can do the following:

Customize and extend the default Home page layout with additional cards that appear based on the plugins you have installed and enabled.
Change quick access links.
Add, reorganize, and remove the following available cards:
- Search bar
- Quick access
- Headline
- Markdown
- Placeholder
- Catalog starred entities
- Featured docs

9.1. Customizing the Home page cards

Administrators can change the fixed height of cards that are in a 12-column grid.

The default Home page is as shown in the following app-config file configuration:

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      dynamicRoutes:
        - path: /
          importName: DynamicHomePage
      mountPoints:
        - mountPoint: home.page/cards
          importName: SearchBar
          config:
            layouts:
              xl: { w: 10, h: 1, x: 1 }
              lg: { w: 10, h: 1, x: 1 }
              md: { w: 10, h: 1, x: 1 }
              sm: { w: 10, h: 1, x: 1 }
              xs: { w: 12, h: 1 }
              xxs: { w: 12, h: 1 }
        - mountPoint: home.page/cards
          importName: QuickAccessCard
          config:
            layouts:
              xl: { w: 7, h: 8 }
              lg: { w: 7, h: 8 }
              md: { w: 7, h: 8 }
              sm: { w: 12, h: 8 }
              xs: { w: 12, h: 8 }
              xxs: { w: 12, h: 8 }
        - mountPoint: home.page/cards
          importName: CatalogStarredEntitiesCard
          config:
            layouts:
              xl: { w: 5, h: 4, x: 7 }
              lg: { w: 5, h: 4, x: 7 }
              md: { w: 5, h: 4, x: 7 }
              sm: { w: 12, h: 4 }
              xs: { w: 12, h: 4 }
              xxs: { w: 12, h: 4 }

Prerequisites

You have administrative access and can modify the app-config.yaml file for dynamic plugin configurations.

Procedure

Configure different cards for your Home page in Red Hat Developer Hub as follows:

Search

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: SearchBar
          config:
            layouts:
              xl: { w: 10, h: 1, x: 1 }
              lg: { w: 10, h: 1, x: 1 }
              md: { w: 10, h: 1, x: 1 }
              sm: { w: 10, h: 1, x: 1 }
              xs: { w: 12, h: 1 }
              xxs: { w: 12, h: 1 }

Table 1. Available props

Prop	Default	Description
`path`	`/search`	Override the linked search path if needed
`queryParam`	`query`	Override the search query parameter name if needed

Quick access

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: QuickAccessCard
          config:
            layouts:
              xl: { h: 8 }
              lg: { h: 8 }
              md: { h: 8 }
              sm: { h: 8 }
              xs: { h: 8 }
              xxs: { h: 8 }

Table 2. Available props

Prop	Default	Description
`title`	`Quick Access`	Override the linked search path if needed
`path`	none	Override the search query parameter name if needed

Headline

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: Headline
          config:
            layouts:
              xl: { h: 1 }
              lg: { h: 1 }
              md: { h: 1 }
              sm: { h: 1 }
              xs: { h: 1 }
              xxs: { h: 1 }
            props:
              title: Important info

Table 3. Available props

Prop	Default	Description
`title`	none	Title

Markdown

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: MarkdownCard
          config:
            layouts:
              xl: { w: 6, h: 4 }
              lg: { w: 6, h: 4 }
              md: { w: 6, h: 4 }
              sm: { w: 6, h: 4 }
              xs: { w: 6, h: 4 }
              xxs: { w: 6, h: 4 }
            props:
              title: Company links
              content: |
                ### RHDH
                * [Website](https://developers.redhat.com/rhdh/overview)
                * [Documentation](https://docs.redhat.com/en/documentation/red_hat_developer_hub/)
                * [GitHub Showcase](https://github.com/janus-idp/backstage-showcase)
                * [GitHub Plugins](https://github.com/janus-idp/backstage-plugins)
        - mountPoint: home.page/cards
          importName: Markdown
          config:
            layouts:
              xl: { w: 6, h: 4, x: 6 }
              lg: { w: 6, h: 4, x: 6 }
              md: { w: 6, h: 4, x: 6 }
              sm: { w: 6, h: 4, x: 6 }
              xs: { w: 6, h: 4, x: 6 }
              xxs: { w: 6, h: 4, x: 6 }
            props:
              title: Important company links
              content: |
                ### RHDH
                * [Website](https://developers.redhat.com/rhdh/overview)
                * [Documentation](https://docs.redhat.com/en/documentation/red_hat_developer_hub/)
                * [GitHub Showcase](https://github.com/janus-idp/backstage-showcase)
                * [GitHub Plugins](https://github.com/janus-idp/backstage-plugins)

Placeholder

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 1, h: 1 }
              lg: { w: 1, h: 1 }
              md: { w: 1, h: 1 }
              sm: { w: 1, h: 1 }
              xs: { w: 1, h: 1 }
              xxs: { w: 1, h: 1 }
            props:
              showBorder: true
              debugContent: '1'

Catalog starred entities

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: CatalogStarredEntitiesCard

Featured docs

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: FeaturedDocsCard

9.2. Defining the layout of the Red Hat Developer Hub Home page

Prerequisites

Include the following optimal parameters in each of your breakpoints:
- width (w)
- height (h)
- position (x and y)

Procedure

Configure your Developer Hub app-config.yaml configuration file by choosing one of the following options:
- Use the full space on smaller windows and half of the space on larger windows as follows:

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 6, h: 2 }
              lg: { w: 6, h: 2 }
              md: { w: 6, h: 2 }
              sm: { w: 12, h: 2 }
              xs: { w: 12, h: 2 }
              xxs: { w: 12, h: 2 }
            props:
              showBorder: true
              debugContent: a placeholder

Show the cards side by side by defining the x parameter as follows:

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 6, h: 2 }
              lg: { w: 6, h: 2 }
              md: { w: 6, h: 2 }
              sm: { w: 12, h: 2 }
              xs: { w: 12, h: 2 }
              xxs: { w: 12, h: 2 }
            props:
              showBorder: true
              debugContent: left
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 6, h: 2, x: 6 }
              lg: { w: 6, h: 2, x: 6 }
              md: { w: 6, h: 2, x: 6 }
              sm: { w: 12, h: 2, x: 0 }
              xs: { w: 12, h: 2, x: 0 }
              xxs: { w: 12, h: 2, x: 0 }
            props:
              showBorder: true
              debugContent: right

However, you can see a second card below this card by default.

Show the cards in three columns by defining the x parameter as follows:

dynamicPlugins:
  frontend:
    janus-idp.backstage-plugin-dynamic-home-page:
      mountPoints:
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 4, h: 2 }
              lg: { w: 4, h: 2 }
              md: { w: 4, h: 2 }
              sm: { w: 6, h: 2 }
              xs: { w: 12, h: 2 }
              xxs: { w: 12, h: 2 }
            props:
              showBorder: true
              debugContent: left
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 4, h: 2, x: 4 }
              lg: { w: 4, h: 2, x: 4 }
              md: { w: 4, h: 2, x: 4 }
              sm: { w: 6, h: 2, x: 6 }
              xs: { w: 12, h: 2 }
              xxs: { w: 12, h: 2 }
            props:
              showBorder: true
              debugContent: center
        - mountPoint: home.page/cards
          importName: Placeholder
          config:
            layouts:
              xl: { w: 4, h: 2, x: 8 }
              lg: { w: 4, h: 2, x: 8 }
              md: { w: 4, h: 2, x: 8 }
              sm: { w: 6, h: 2 }
              xs: { w: 12, h: 2 }
              xxs: { w: 12, h: 2 }
            props:
              showBorder: true
              debugContent: right

10. Customizing the Quick access card

To access the Home page in Red Hat Developer Hub, the base URL must include the /developer-hub proxy. You can configure the Home page by passing the data into the app-config.yaml file as a proxy. You can provide data to the Home page from the following sources:

JSON files hosted on GitHub or GitLab.
A dedicated service that provides the Home page data in JSON format using an API.

10.1. Using hosted JSON files to provide data to the Quick access card

Prerequisites

You have installed Red Hat Developer Hub by using either the Operator or Helm chart. See Installing Red Hat Developer Hub on OpenShift Container Platform.

Procedure

To access the data from the JSON files, add the following code to the Developer Hub app-config.yaml configuration file:

Add the following code to the app-config.yaml file:

proxy:
  endpoints:
    # Other Proxies
    # customize developer hub instance
    '/developer-hub':
      target: <DOMAIN_URL> # i.e https://raw.githubusercontent.com/
      pathRewrite:
        '^/api/proxy/developer-hub': <path to json file> # i.e /janus-idp/backstage-showcase/main/packages/app/public/homepage/data.json
      changeOrigin: true
      secure: true
      # Change to "false" in case of using self hosted cluster with a self-signed certificate
      headers:
	<HEADER_KEY>: <HEADER_VALUE> # optional and can be passed as needed i.e Authorization can be passed for private GitHub repo and PRIVATE-TOKEN can be passed for private GitLab repo

10.2. Using a dedicated service to provide data to the Quick access card

When using a dedicated service, you can do the following:

Use the same service to provide the data to all configurable Developer Hub pages or use a different service for each page.
Use the red-hat-developer-hub-customization-provider as an example service, which provides data for both the Home and Tech Radar pages. The red-hat-developer-hub-customization-provider service provides the same data as default Developer Hub data. You can fork the red-hat-developer-hub-customization-provider service repository from GitHub and modify it with your own data, if required.
Deploy the red-hat-developer-hub-customization-provider service and the Developer Hub Helm chart on the same cluster.

Prerequisites

You have installed the Red Hat Developer Hub using Helm Chart. For more information, see Installing Red Hat Developer Hub on OpenShift Container Platform with the Helm chart.

Procedure

To use a separate service to provide the Home page data, complete the following steps:

From the Developer perspective in the Red Hat OpenShift Container Platform web console, click +Add > Import from Git.
Enter the URL of your Git repository into the Git Repo URL field.
To use the red-hat-developer-hub-customization-provider service, add the URL for the red-hat-developer-hub-customization-provider repository or your fork of the repository containing your customizations.
On the General tab, enter red-hat-developer-hub-customization-provider in the Name field and click Create.
On the Advanced Options tab, copy the value from the Target Port.
Note
The Target Port automatically generates a Kubernetes or OpenShift Container Platform service to communicate with.
Add the following code to the app-config-rhdh.yaml file:
```
proxy:
  endpoints:
    # Other Proxies
    # customize developer hub instance
    '/developer-hub':
      target: ${HOMEPAGE_DATA_URL}
      changeOrigin: true
      # Change to "false" in case of using self-hosted cluster with a self-signed certificate
      secure: true
```
where HOMEPAGE_DATA_URL is defined as http://<SERVICE_NAME>:8080, for example, http://rhdh-customization-provider:8080.
Note
The red-hat-developer-hub-customization-provider service contains the 8080 port by default. If you are using a custom port, you can specify it with the 'PORT' environmental variable in the app-config-rhdh.yaml file.
Replace the HOMEPAGE_DATA_URL by adding the URL to rhdh-secrets or by directly replacing it in your custom ConfigMap.
Delete the Developer Hub pod to ensure that the new configurations are loaded correctly.

Verification

To view the service, navigate to the Administrator perspective in the OpenShift Container Platform web console and click Networking > Service.
Note
You can also view the Service Resources in the Topology view.

Ensure that the provided API URL for the Home page returns the data in JSON format as shown in the following example:

[
  {
    "title": "Dropdown 1",
    "isExpanded": false,
    "links": [
      {
        "iconUrl": "https://imagehost.com/image.png",
        "label": "Dropdown 1 Item 1",
        "url": "https://example.com/"
      },
      {
        "iconUrl": "https://imagehost2.org/icon.png",
        "label": "Dropdown 1 Item 2",
        "url": ""
      }
    ]
  },
  {
    "title": "Dropdown 2",
    "isExpanded": true,
    "links": [
      {
        "iconUrl": "http://imagehost3.edu/img.jpg",
        "label": "Dropdown 2 Item 1",
        "url": "http://example.com"
      }
    ]
  }
]

Note

If the request call fails or is not configured, the Developer Hub instance falls back to the default local data.

If the images or icons do not load, then allowlist them by adding your image or icon host URLs to the content security policy’s (csp) img-src in your custom ConfigMap as follows:

kind: ConfigMap
apiVersion: v1
metadata:
  name: app-config-rhdh
data:
  app-config-rhdh.yaml: |
    app:
      title: Red Hat Developer Hub
    backend:
      csp:
        connect-src:
          - "'self'"
          - 'http:'
          - 'https:'
        img-src:
          - "'self'"
          - 'data:'
          - <image host url 1>
          - <image host url 2>
          - <image host url 3>
    # Other Configurations

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