Add a new service to Phalanx¶

Once you have a chart and a Docker image (see Create a new service) and you have added your static service secrets to 1Password (see Add a secret with 1Password and VaultSecret), you need to integrate your service into Phalanx. This is done by creating an Argo CD application that manages your service. This consists of an Application resource that’s used by Argo CD and a small wrapper chart in the Phalanx repository that holds the values-*.yaml files to configure your service for each environment in which it’s deployed.

Add the wrapper chart¶

Create a directory in /services named for the service (which should almost always be the same as the name of its chart).
Create a Chart.yaml file in that directory for the wrapper chart. This should look something like this:
```
apiVersion: v2
name: example
version: 1.0.0
dependencies:
  - name: example
    version: 1.3.2
    repository: https://lsst-sqre.github.io/charts/
  - name: pull-secret
    version: 0.1.2
    repository: https://lsst-sqre.github.io/charts/
```
The name field should be the same as the name of the directory, which again should be the same as the name of your chart. The version field should always be 1.0.0 (see Chart versioning for an explanation). The first entry in dependencies should point to your chart and pin its current version. (Yes, this means you will need to make a PR against Phalanx for each new version of your chart.) If you are directly referencing an external chart, the repository property may be different. Finally, include the pull-secret dependency as-is. This is used to configure a Docker pull secret that you will reference later.
For each environment in which your service will run, create a values-<environment>.yaml file in this directory. This should hold only the customization per Rubin Science Platform deployment. Any shared configuration should go into the defaults of your chart. (An exception is if you are using an external chart directly, in which case you will need to add all configuration required for that chart. See Configure the external chart for more discussion.)

Some common things to need to configure per-environment:
- The ingress hostname (usually ingress.host)
- The vaultSecretsPath for a secret
Always tell any pods deployed by your service to use a pull secret named pull-secret. If you are using the default Helm template, this will mean a block like:
```
imagePullSecrets:
  - name: "pull-secret"
```
under the section for your chart. If you are using an external chart, see its documentation for how to configure pull secrets. Configuring a pull secret is important to avoid running into Docker pull rate limits, which could otherwise prevent a pod from starting.

All configuration for your chart must be under a key named for your chart. For example, for a service named example, a typical configuration may look like:
```
example:
  imagePullSecrets:
    - name: "pull-secret"

  ingress:
    host: "data.lsst.cloud"

  vaultSecretsPath: "secret/k8s_operator/data.lsst.cloud/example"
```
That example: on the top line and the indentation is important. If you omit it, all of your configuration will be silently ignored.

Finally, every values-*.yaml file (at least for now, until we find a better approach) must have, at the bottom, a stanza like:
```
pull-secret:
  enabled: true
  path: "secret/k8s_operator/<url-for-environment>/pull-secret"
```
See all the other directories under /services for examples. You may want to copy and paste the basic setup including the pull-secret configuration from another service to save effort.

Add the Argo CD application¶

Create the Argo CD application resource. This is a new file in /science-platform/templates named <service>-application.yaml where <service> must match the name of the directory created above. The contents of this file should look like:

{{- if .Values.<service>.enabled -}}
apiVersion: v1
kind: Namespace
metadata:
  name: <service>
spec:
  finalizers:
    - kubernetes
---
apiVersion: argoproj.io/v1alpha1
kind: Application
metadata:
  name: <service>
  namespace: argocd
  finalizers:
    - resources-finalizer.argocd.argoproj.io
spec:
  destination:
    namespace: <service>
    server: https://kubernetes.default.svc
  project: default
  source:
    path: services/<service>
    repoURL: {{ .Values.repoURL }}
    targetRevision: {{ .Values.revision }}
    helm:
      valueFiles:
        - values-{{ .Values.environment }}.yaml
{{- end -}}

replacing every instance of <service> with the name of your service. This creates the namespace and Argo CD application for your service.

Finally, edit each of the values-*.yaml files in /science-platform and add a stanza for your service. The stanza in values.yaml should always say:
```
<service>:
  enabled: false
```
replacing <service> with the name of your service. For the other environments, set enabled to true if your service should be deployed there. You may want to start in a dev or int environment and enable it in production environments later.

Navigation

Add a new service to Phalanx¶

Add the wrapper chart¶

Add the Argo CD application¶