fix: tolerate optional fields from external pepr module definitions (#…

…1732)

## Description

This PR relates to an issue where customLabels were not being applied to
a Helm chart after running `pepr build`.

## Related Issue

Relates to #1713

## Type of change

- [x] Bug fix (non-breaking change which fixes an issue)
- [ ] New feature (non-breaking change which adds functionality)
- [ ] Other (security config, docs update, etc)

## Checklist before merging
- [ ] Unit,
[Journey](https://github.com/defenseunicorns/pepr/tree/main/journey),
[E2E Tests](https://github.com/defenseunicorns/pepr-excellent-examples),
[docs](https://github.com/defenseunicorns/pepr/tree/main/docs),
[adr](https://github.com/defenseunicorns/pepr/tree/main/adr) added or
updated as needed
- [x] [Contributor Guide
Steps](https://docs.pepr.dev/main/contribute/#submitting-a-pull-request)
followed

src/cli/init/templates.ts

@@ -6,16 +6,17 @@ import { inspect } from "util";
 import { v4 as uuidv4, v5 as uuidv5 } from "uuid";
 
 import eslintJSON from "../../templates/.eslintrc.template.json";
+import peprSnippetsJSON from "../../templates/pepr.code-snippets.json";
 import prettierJSON from "../../templates/.prettierrc.json";
 import samplesJSON from "../../templates/capabilities/hello-pepr.samples.json";
-import { gitIgnore, helloPeprTS, packageJSON, peprTS, readmeMd } from "../../templates/data.json";
-import peprSnippetsJSON from "../../templates/pepr.code-snippets.json";
 import settingsJSON from "../../templates/settings.json";
 import tsConfigJSON from "../../templates/tsconfig.module.json";
-import { sanitizeName } from "./utils";
+import { CustomLabels } from "../../lib/core/module";
 import { InitOptions } from "../types";
-import { V1PolicyRule as PolicyRule } from "@kubernetes/client-node";
 import { OnError, RbacMode } from "./enums";
+import { V1PolicyRule as PolicyRule } from "@kubernetes/client-node";
+import { gitIgnore, helloPeprTS, packageJSON, peprTS, readmeMd } from "../../templates/data.json";
+import { sanitizeName } from "./utils";
 
 export const { dependencies, devDependencies, peerDependencies, scripts, version } = packageJSON;
 
@@ -30,7 +31,7 @@ type peprPackageJSON = {
       uuid: string;
       onError: OnError;
       webhookTimeout: number;
-      customLabels: { namespace: Record<string, string> };
+      customLabels: CustomLabels;
       alwaysIgnore: { namespaces: string[] };
       includedFiles: string[];
       env: object;

src/lib/assets/index.test.ts

@@ -3,6 +3,7 @@
 import { it, describe, expect } from "@jest/globals";
 import { createWebhookYaml } from "./index";
 import { kind } from "kubernetes-fluent-client";
+import { ModuleConfig } from "../core/module";
 
 describe("createWebhookYaml", () => {
   const webhookConfiguration = new kind.MutatingWebhookConfiguration();
@@ -37,13 +38,14 @@ describe("createWebhookYaml", () => {
     },
   ];
 
-  const moduleConfig = {
+  const moduleConfig: ModuleConfig = {
     onError: "reject",
     webhookTimeout: 15,
     uuid: "some-uuid",
     alwaysIgnore: {
       namespaces: ["kube-system", "pepr-system"],
     },
+    customLabels: { namespace: { "pepr.dev": "" } },
   };
 
   it("replaces placeholders in the YAML correctly", () => {

src/lib/core/module.ts

@@ -12,37 +12,41 @@ import { V1PolicyRule as PolicyRule } from "@kubernetes/client-node";
 import { resolveIgnoreNamespaces } from "../assets/webhooks";
 
 /** Custom Labels Type for package.json */
-export interface CustomLabels {
-  namespace?: Record<string, string>;
-}
-/** Global configuration for the Pepr runtime. */
-export type ModuleConfig = {
+
+export type CustomLabels = { namespace: Record<string, string> } | Record<string, never>;
+
+/** Configuration that MAY be set a Pepr module's package.json. */
+export type ModuleConfigOptions = {
   /** The Pepr version this module uses */
-  peprVersion?: string;
+  peprVersion: string;
   /** The user-defined version of the module */
-  appVersion?: string;
-  /** A unique identifier for this Pepr module. This is automatically generated by Pepr. */
-  uuid: string;
+  appVersion: string;
   /** A description of the Pepr module and what it does. */
-  description?: string;
+  description: string;
   /** The webhookTimeout */
-  webhookTimeout?: number;
+  webhookTimeout: number;
   /** Reject K8s resource AdmissionRequests on error. */
-  onError?: string;
-  /** Configure global exclusions that will never be processed by Pepr. */
-  alwaysIgnore: WebhookIgnore;
+  onError: string;
   /** Define the log level for the in-cluster controllers */
-  logLevel?: string;
+  logLevel: string;
   /** Propagate env variables to in-cluster controllers */
-  env?: Record<string, string>;
-  /** Custom Labels for Kubernetes Objects */
-  customLabels?: CustomLabels;
+  env: Record<string, string>;
   /** Custom RBAC rules */
-  rbac?: PolicyRule[];
+  rbac: PolicyRule[];
   /** The RBAC mode; if "scoped", generates scoped rules, otherwise uses wildcard rules. */
-  rbacMode?: string;
+  rbacMode: string;
+  /** Custom Labels for Kubernetes Objects */
+  customLabels: CustomLabels;
 };
 
+/** Global configuration for the Pepr runtime. */
+export type ModuleConfig = {
+  /** A unique identifier for this Pepr module. This is automatically generated by Pepr. */
+  uuid: string;
+  /** Configure global exclusions that will never be processed by Pepr. */
+  alwaysIgnore: WebhookIgnore;
+} & Partial<ModuleConfigOptions>;
+
 export type PackageJSON = {
   description: string;
   pepr: ModuleConfig;