Qhub Extension (Ready for Review) (nebari-dev#886)

* add support for helm_extensions in qhub-config.yaml file

* add helm_extensions documentation

Co-authored-by: Adam-D-Lewis <>

docs/source/admin_guide/custom-helm-charts.md

@@ -0,0 +1,18 @@
+# Other Helm Charts
+
+Arbitrary helm charts can be deployed and managed with the qhub-config.yaml file.
+
+As an example, deploying the redis helm chart with qhub might look like the below:
+
+```yaml
+helm_extensions:
+  - name: my-redis-deployment
+    repository: https://charts.bitnami.com/bitnami
+    chart: redis
+    version: 15.5.1
+    overrides:
+        diagnosticMode:
+            enabled: true
+```
+
+The `overrides` section is optional, but corresponds to the helm chart's [values.yaml](https://helm.sh/docs/chart_template_guide/values_files/) file, and allows you to override the default helm chart settings.

docs/source/admin_guide/index.md

@@ -13,5 +13,6 @@ system_maintenance.md
 monitoring.md
 clearml.md
 prefect.md
+custom-helm-charts.md
 faq.md
 ```

qhub/initialize.py

@@ -49,6 +49,7 @@
             "h2_color": "#652e8e",
         }
     },
+    "helm_extensions": [],
     "monitoring": {
         "enabled": True,
     },

qhub/schema.py

@@ -58,6 +58,15 @@ class CICD(Base):
     after_script: typing.Optional[typing.List[str]]
 
 
+# ======== Generic Helm Extensions ========
+class HelmExtension(Base):
+    name: str
+    repository: str
+    chart: str
+    version: str
+    overrides: typing.Optional[typing.Dict]
+
+
 # ============== Monitoring =============
 
 
@@ -419,6 +428,7 @@ class Main(Base):
         TerraformModules
     ]  # No longer used, so ignored, but could still be in qhub-config.yaml
     certificate: Certificate
+    helm_extensions: typing.Optional[typing.List[HelmExtension]]
     prefect: typing.Optional[Prefect]
     cdsdashboards: CDSDashboards
     security: Security

qhub/template/cookiecutter.json

@@ -13,6 +13,7 @@
     "certificate": {
       "type": "self-signed"
     },
+    "helm_extensions": [],
     "monitoring": {
         "enabled": null
     },

qhub/template/{{ cookiecutter.repo_directory }}/infrastructure/kubernetes.tf

@@ -312,6 +312,27 @@ module "qhub" {
 
 }
 
+{% for helm_extension in cookiecutter.helm_extensions -%}
+module "{{helm_extension['name'] }}-extension" {
+  source       = "./modules/kubernetes/services/helm-extensions"
+  name       = "{{ helm_extension['name'] }}"
+  namespace  = var.environment
+  repository = "{{ helm_extension['repository'] }}"
+  chart      = "{{ helm_extension['chart'] }}"
+  chart_version    = "{{ helm_extension['version'] }}"
+  {% if 'overrides' in helm_extension -%}
+  overrides = [<<EOT
+{{ helm_extension['overrides']|yamlify -}}
+    EOT
+    ]
+  {% endif -%}
+  depends_on = [
+    module.qhub
+  ]
+}
+
+{% endfor -%}
+
 {% if cookiecutter.prefect.enabled -%}
 module "prefect" {
   source = "./modules/kubernetes/services/prefect"

qhub/template/{{ cookiecutter.repo_directory }}/infrastructure/modules/kubernetes/services/helm-extensions/main.tf

@@ -0,0 +1,9 @@
+resource "helm_release" "custom-helm-deployment" {
+  name       = var.name
+  namespace  = var.namespace
+  repository = var.repository
+  chart      = var.chart
+  version    = var.chart_version
+
+  values = var.overrides
+}

qhub/template/{{ cookiecutter.repo_directory }}/infrastructure/modules/kubernetes/services/helm-extensions/variables.tf

@@ -0,0 +1,32 @@
+variable "name" {
+  description = "helm deployment name"
+  type        = string
+  default     = "dev"
+}
+
+variable "namespace" {
+  description = "deploy helm chart on this namespace"
+  type        = string
+  default     = "dev"
+}
+
+variable "repository" {
+  description = "helm chart repository"
+  type        = string
+}
+
+variable "chart" {
+  description = "helm chart name in helm chart repository"
+  type        = string
+}
+
+variable "chart_version" {
+  description = "Helm chart version"
+  type        = string
+}
+
+variable "overrides" {
+  description = "Overrides for the helm chart values"
+  type        = list
+  default     = []
+}