feat: Expose extraTemplateSpec, fix api extraSpec location

[DelineaMosher]

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• I have filled in the "How did you test this code" section below?

Changes

Add extraTemplateSpec to be added to spec.template.spec in 5 templates. Allows specifying additional fields like priorityClassName. Addresses #446

1. deployment-api.yaml
2. deployment-frontend.yaml
3. deployment-pgbouncer.yaml
4. deployment-sse.yaml
5. deployment-task-processor.yaml

In values.yaml move extraSpec outside of bootstrap and directly under api. Template reads from .Values.api.extraSpec, not .Values.api.bootsrap.extraSpec.

How did you test this code?

1. Compare baseline

helm template flagsmith ./charts/flagsmith > /tmp/default.yaml
helm template flagsmith ./charts/flagsmith > /tmp/baseline.yaml
diff /tmp/baseline.yaml /tmp/default.yaml

2. priorityClassName renders at correct YAML level

helm template flagsmith ./charts/flagsmith \
  --set api.extraTemplateSpec.priorityClassName=high-priority \
  --show-only templates/deployment-api.yaml \
  | yq '.spec.template.spec.priorityClassName'

3. Verify arbitrary field renders

helm template flagsmith ./charts/flagsmith \
  --set api.extraTemplateSpec.runtimeClassName=gvisor \
  --set api.extraTemplateSpec.hostNetwork=false \
  --show-only templates/deployment-api.yaml \
  | yq '.spec.template.spec'

4. Verify all 5 deployments

for tpl in deployment-api deployment-frontend deployment-task-processor deployment-sse deployment-pgbouncer; do
  case $tpl in
    deployment-frontend)     extra="--set api.separateApiAndFrontend=true --set frontend.enabled=true --set frontend.extraTemplateSpec.priorityClassName=test" ;;
    deployment-task-processor) extra="--set taskProcessor.enabled=true --set taskProcessor.extraTemplateSpec.priorityClassName=test" ;;
    deployment-sse)          extra="--set sse.enabled=true --set sse.extraTemplateSpec.priorityClassName=test" ;;
    deployment-pgbouncer)    extra="--set pgbouncer.enabled=true --set pgbouncer.extraTemplateSpec.priorityClassName=test" ;;
    deployment-api)          extra="--set api.extraTemplateSpec.priorityClassName=test" ;;
  esac
                                                                                                                                                                  
  result=$(eval helm template flagsmith ./charts/flagsmith $extra \
    --show-only templates/${tpl}.yaml 2>&1 \
    | yq '.spec.template.spec.priorityClassName')
                                                                                                                                                                  
  echo "$tpl: $result"
done

5. Verify api.extraSpec fix

helm template flagsmith ./charts/flagsmith \
  --set api.extraSpec.strategy.type=Recreate \
  --show-only templates/deployment-api.yaml \
  | yq '.spec.strategy.type'

6 Verify volumes: included only if extraVolumes is specified.

helm template flagsmith ./charts/flagsmith \
    --show-only templates/deployment-api.yaml 2>&1 | yq '.spec.template.spec.volumes'

helm template flagsmith ./charts/flagsmith \
    --set 'api.extraVolumes[0].name=test-vol' \
    --set 'api.extraVolumes[0].emptyDir.medium=Memory' \
    --show-only templates/deployment-api.yaml 2>&1 | yq '.spec.template.spec.volumes'

# etc for other charts.

[gemini-code-assist]

Code Review

This pull request adds the extraTemplateSpec field to several deployment templates (api, frontend, pgbouncer, sse, and task-processor) to allow custom configuration of spec.template.spec. The reviewer identified a critical issue across all these templates: if extraVolumes is empty but extraTemplateSpec is provided, the templates will render an empty volumes: key, causing Kubernetes API validation to fail. The reviewer suggests conditionally rendering the volumes: block only when volumes are actually defined.

[germangarces]

Thanks for the contrib @DelineaMosher
👍 LGTM