SOLUTION.md

Generate a update-scope-schema workspace generator:

nx generate @nrwl/workspace:workspace-generator update-scope-schema

Change default project

import { Tree, formatFiles, updateJson } from '@nrwl/devkit';

export default async function (host: Tree) {
  await updateJson(host, 'workspace.json', (workspaceJson) => {
    workspaceJson.defaultProject = 'api';
    return workspaceJson;
  });
  await formatFiles(host);
}

Update schema with formatter

import { Tree, updateJson, formatFiles, readJson } from '@nrwl/devkit';

function getScopes(nxJson: any) {
  const projects: any[] = Object.values(nxJson.projects);
  const allScopes = projects
    .map((project) =>
      project.tags.filter((tag: string) => tag.startsWith('scope:'))
    )
    .reduce((acc, tags) => [...acc, ...tags], [])
    .map((scope: string) => scope.slice(6));
  return [...new Set(allScopes)];
}

export default async function (host: Tree) {
  const scopes = getScopes(readJson(host, 'nx.json'));
  updateJson(host, 'tools/generators/util-lib/schema.json', (schemaJson) => {
    schemaJson.properties.directory['x-prompt'].items = scopes.map((scope) => ({
      value: scope,
      label: scope,
    }));
    return schemaJson;
  });
  await formatFiles(host);
}

Final generator code

import { Tree, updateJson, formatFiles, readJson } from '@nrwl/devkit';

function getScopes(nxJson: any) {
  const projects: any[] = Object.values(nxJson.projects);
  const allScopes: string[] = projects
    .map((project) =>
      project.tags.filter((tag: string) => tag.startsWith('scope:'))
    )
    .reduce((acc, tags) => [...acc, ...tags], [])
    .map((scope: string) => scope.slice(6));
  return [...new Set(allScopes)];
}

function replaceScopes(content: string, scopes: string[]): string {
  const joinScopes = scopes.map((s) => `'${s}'`).join(' | ');
  const PATTERN = /interface Schema \{\n.*\n.*\n\}/gm;
  return content.replace(
    PATTERN,
    `interface Schema {
  name: string;
  directory: ${joinScopes};
}`
  );
}

export default async function (host: Tree) {
  const scopes = getScopes(readJson(host, 'nx.json'));
  updateJson(host, 'tools/generators/util-lib/schema.json', (schemaJson) => {
    schemaJson.properties.directory['x-prompt'].items = scopes.map((scope) => ({
      value: scope,
      label: scope,
    }));
    return schemaJson;
  });
  const content = host.read('tools/generators/util-lib/index.ts', 'utf-8');
  const newContent = replaceScopes(content, scopes);
  host.write('tools/generators/util-lib/index.ts', newContent);
  await formatFiles(host);
}

BONUS 1 SOLUTION

function addScopeIfMissing(host: Tree) {
  updateJson(host, 'nx.json', (json) => {
    Object.keys(json.projects).forEach((projectName) => {
      if (
        !json.projects[projectName].tags.some((tag) => tag.startsWith('scope:'))
      ) {
        const scope = projectName.split('-')[0];
        json.projects[projectName].tags.push(`scope:${scope}`);
      }
    });
    return json;
  });
}

BONUS 2 SOLUTION

{
  "scripts": {
    "postinstall": "husky install",
    "pre-commit": "run run nx workspace-generator update-scope-schema"
  }
}