helm-service: Make public deployment URI configurable

[christian-kreuzberger-dtx]

With Keptn 0.7.x we introduced the option for continuous deployments to configure the ingress port, protocol, and suffix, e.g.:
https://keptn.sh/docs/0.7.x/continuous_delivery/expose_services/#create-configmap-with-ingress-information

This is already used here:

keptn/helm-service/controller/helm/generated_chart_handler.go

Line 139 in a8871e3

svc.Name + "." + c.getNamespace(project, stageName) + "." + mesh.GetIngressHostnameSuffix(), // service_name.dev.123.45.67.89.xip.io

and here

keptn/helm-service/controller/workflow_engine_replacer.go

Line 95 in a8871e3

publicDeploymentURI := protocol + "://" + keptnHandler.KeptnBase.Event.GetService() + "." + keptnHandler.KeptnBase.Event.GetProject() + "-" + keptnHandler.KeptnBase.Event.GetStage() + "." + ingressHostnameSuffix + ":" + port

This generates hostnames that look as follows:

${INGRESS_PROTOCOL}://${service}.${project}-${stage}.${INGRESS_HOSTNAME}:${INGRESS_PORT}

Example: https://carts.sockshop-dev.127.0.0.1.nip.io:443

Enhancement

I believe that we can go one step further and make the hostname generation fully configurable, by introducing a config with placeholders, e.g.:

HOSTNAME_TEMPLATE=${INGRESS_PROTOCOL}://${service}.${project}-${stage}.${INGRESS_HOSTNAME}:${INGRESS_PORT}

In addition, this allows users to change certain parts of the logic, e.g.,

• ...${service}-${stage}.${project}... (carts-dev.sockshop.127.0.0.1.nip.io)
• ...${service}-${stage}-${project}... (carts-dev-sockshop.127.0.0.1.nip.io)

The later has the benefit that you can use a wildcard certificate for ${INGRESS_HOSTNAME}, instead of having to generate wildcard certificates for each stage.

Definition of Done

• extend ingress_config.go with a function to read HOSTNAME_TEMPLATE
• Change the URL generation in helm-service such that it uses and processes the hostname template (please use a built-in templating syntax of GoLang)
• The default behaviour (service.project-stage....) must still work as it was

[lonerapier]

If anyone is not working on this, then I would like to take the issue. I may need some guidance on how to approach this.

[christian-kreuzberger-dtx]

Hi! Thanks for approaching us, I've assigned this ticket to you.

I may need some guidance on how to approach this.

For organizational questions and processes, please go through our Contribution Guide.

For coding, first thing I recommend is installing Keptn with continuous delivery enabled on a Kubernetes cluster (either in the Cloud or locally using K3s) - see https://keptn.sh/docs/0.7.x/operate/install/ for options.

Fork and clone this repo, branch away from master (e.g., git checkout -b feature/2362/helm_deployment_uri) and start coding in the helm-service directory ;)

I've linked two files and the respective lines of code in the issue above, this should be a good starting point. If you need any more guidance, please let us know.

[lonerapier]

@christian-kreuzberger-dtx I am not able to understand how are we going to define HOSTNAME_TEMPLATE and how would we use it? Is it going to be an env variable also? Or do we have to define a new struct for HOSTNAME_TEMPLATE?
Can you elaborate a bit more?

[christian-kreuzberger-dtx]

For now HOSTNAME_TEMPLATE is going to be an environment variable, same as here

[christian-kreuzberger-dtx]

Re-assigning this issue to @warber