@Gavinok one note worth mentioning (thanks @loneil for reminding me): the QR page is served via a get endpoint as it needs to be processed by the server using a Jinja template to inject the values relevant for the transaction (namely the URL that the QR code will link to). We need to ensure this step is retained so that all variables exposed by the vc-authn service can be referenced and correctly resolved when rendering a template, even if it is a custom one.

Here are some general plans for this ticket

We want to make the directory and template file into env vars and use a helm volume replacing the templates directory for user defined static element.

Location that needs to be made into a env var https://github.com/bcgov/vc-authn-oidc/blob/main/oidc-controller/api/main.py#L51

How we currently import user_variable_substitution.py here https://github.com/bcgov/vc-authn-oidc/blob/main/charts/vc-authn-oidc/templates/configmap.yaml#L9

Make the directory configurable here https://github.com/bcgov/vc-authn-oidc/blob/main/charts/vc-authn-oidc/values.yaml

Add a new volume here https://github.com/bcgov/vc-authn-oidc/blob/main/charts/vc-authn-oidc/templates/deployment.yaml#L39

The mount this new volume here https://github.com/bcgov/vc-authn-oidc/blob/main/charts/vc-authn-oidc/templates/deployment.yaml#L132

volumes:
  - name: jwt-token
    secret:
      secretName: {{ include "vc-authn-oidc.token.secretName" . }}
      defaultMode: 256
  - name: controller-config
    configMap:
      name: {{ include "global.fullname" . }}-controller-config
  - name: template
    emptyDir: {}

containers:
  - name: {{ include "global.fullname" . }}
    image: "{{ .Values.image.repository }}:{{ .Values.image.tag }}"
    imagePullPolicy: {{ .Values.image.pullPolicy }}
    volumeMounts:
      - name: template
        mountPath: /path/to/template

As far as the handling of passing values into templates a formal api will be outlined on the exposed variables

Users will be responsible for making use of these exposed variables in their templates.

@esune Since these exposed values are compiled at runtime these templates can be replaced at any time as long as the assets needed are configured https://github.com/bcgov/vc-authn-oidc/blob/main/charts/vc-authn-oidc/values.yaml so that all the templates can access the associated js/css/etc

I have decided that the best mode of action would be to now extract the QR code functionality into separate files to allow for the core styling to be modified by users.