fix(cli): "EACCES: Permission denied" on 'cdk init'

packages/aws-cdk/lib/init-hooks.ts

@@ -0,0 +1,90 @@
+import * as path from 'path';
+import { shell } from './os';
+
+export type SubstitutePlaceholders = (...fileNames: string[]) => Promise<void>;
+
+/**
+ * Helpers passed to hook functions
+ */
+export interface HookContext {
+  /**
+   * Callback function to replace placeholders on arbitrary files
+   *
+   * This makes token substitution available to non-`.template` files.
+   */
+  readonly substitutePlaceholdersIn: SubstitutePlaceholders;
+
+  /**
+   * Return a single placeholder
+   */
+  placeholder(name: string): string;
+}
+
+export type InvokeHook = (targetDirectory: string, context: HookContext) => Promise<void>;
+
+export interface HookTarget {
+  readonly targetDirectory: string;
+  readonly templateName: string;
+  readonly language: string;
+}
+
+/**
+ * Invoke hooks for the given init template
+ *
+ * Sometimes templates need more complex logic than just replacing tokens. A 'hook' can be
+ * used to do additional processing other than copying files.
+ *
+ * Hooks used to be defined externally to the CLI, by running arbitrarily
+ * substituted shell scripts in the target directory.
+ *
+ * In practice, they're all TypeScript files and all the same, and the dynamism
+ * that the original solution allowed wasn't used at all. Worse, since the CLI
+ * is now bundled the hooks can't even reuse code from the CLI libraries at all
+ * anymore, so all shared code would have to be copy/pasted.
+ *
+ * Bundle hooks as built-ins into the CLI, so they get bundled and can take advantage
+ * of all shared code.
+ */
+export async function invokeBuiltinHooks(target: HookTarget, context: HookContext) {
+  switch (target.language) {
+    case 'csharp':
+      if (['app', 'sample-app'].includes(target.templateName)) {
+        return dotnetAddProject(target.targetDirectory, context);
+      }
+      break;
+
+    case 'fsharp':
+      if (['app', 'sample-app'].includes(target.templateName)) {
+        return dotnetAddProject(target.targetDirectory, context, 'fsproj');
+      }
+      break;
+
+    case 'python':
+      // We can't call this file 'requirements.template.txt' because Dependabot needs to be able to find it.
+      // Therefore, keep the in-repo name but still substitute placeholders.
+      await context.substitutePlaceholdersIn('requirements.txt');
+      break;
+
+    case 'java':
+      // We can't call this file 'pom.template.xml'... for the same reason as Python above.
+      await context.substitutePlaceholdersIn('pom.xml');
+      break;
+
+    case 'javascript':
+    case 'typescript':
+      // See above, but for 'package.json'.
+      await context.substitutePlaceholdersIn('package.json');
+
+  }
+}
+
+async function dotnetAddProject(targetDirectory: string, context: HookContext, ext = 'csproj') {
+  const pname = context.placeholder('name.PascalCased');
+  const slnPath = path.join(targetDirectory, 'src', `${pname}.sln`);
+  const csprojPath = path.join(targetDirectory, 'src', pname, `${pname}.${ext}`);
+  try {
+    await shell(['dotnet', 'sln', slnPath, 'add', csprojPath]);
+  } catch (e) {
+    throw new Error(`Could not add project ${pname}.${ext} to solution ${pname}.sln. ${e.message}`);
+  }
+};