build(docs-infra): add a tool to create new examples (#39283)

This tool can be run from anywhere in the aio folder as: ```sh yarn create-example <example-name> ``` It will create some basic scaffold files to get the example started. After creation the developer should then use `yarn boilerplate:add` or similar to ensure that the example can be run and tested. You can optionally provide an absolute path to a pre-existing CLI project and it will copy over appropriate files (ignoring boilerplate) to the newly created example. ```sh yarn create-example <example-name> /path/to/other/cli/project ``` Fixes #39275 PR Close #39283
2020-10-15 12:05:14 +01:00
parent 81aa119739
commit 34b74cecb6
19 changed files with 440 additions and 120 deletions
@@ -0,0 +1,140 @@
+const fs = require('fs-extra');
+const glob = require('glob');
+const ignore = require('ignore');
+const path = require('canonical-path');
+const shelljs = require('shelljs');
+const yargs = require('yargs');
+
+const {EXAMPLES_BASE_PATH, EXAMPLE_CONFIG_FILENAME, SHARED_PATH, STACKBLITZ_CONFIG_FILENAME} =
+    require('./constants');
+const BASIC_SOURCE_PATH = path.resolve(SHARED_PATH, 'example-scaffold');
+
+shelljs.set('-e');
+
+if (require.main === module) {
+  const options =
+      yargs(process.argv.slice(2))
+          .command(
+              '$0 <name> [source]',
+              [
+                'Create a new <name> example.',
+                '',
+                'If [source] is provided then the relevant files from the CLI project at that path are copied into the example.',
+              ].join('\n'))
+          .strict()
+          .version(false)
+          .argv;
+
+  const exampleName = options.name;
+  const examplePath = path.resolve(EXAMPLES_BASE_PATH, exampleName);
+
+  console.log('Creating new example at', examplePath);
+  createEmptyExample(exampleName, examplePath);
+
+  const sourcePath =
+      options.source !== undefined ? path.resolve(options.source) : BASIC_SOURCE_PATH;
+  console.log('Copying files from', sourcePath);
+  copyExampleFiles(sourcePath, examplePath, exampleName);
+
+  console.log(`The new "${exampleName}" example has been created.`);
+  console.log('Now run "yarn boilerplate:add" to set it up for development.');
+  console.log(
+      'You can find more info on working with docs examples in aio/tools/examples/README.md.')
+}
+
+/**
+ * Create the directory and marker files for the new example.
+ */
+function createEmptyExample(exampleName, examplePath) {
+  ensureExamplePath(examplePath);
+  writeExampleConfigFile(examplePath);
+  writeStackBlitzFile(exampleName, examplePath);
+}
+
+/**
+ * Ensure that the new example directory exists.
+ */
+function ensureExamplePath(examplePath) {
+  if (fs.existsSync(examplePath)) {
+    throw new Error(
+        `Unable to create example. The path to the new example already exists: ${examplePath}`);
+  }
+  fs.ensureDirSync(examplePath);
+}
+
+/**
+ * Write the `example-config.json` file to the new example.
+ */
+function writeExampleConfigFile(examplePath) {
+  fs.writeFileSync(path.resolve(examplePath, EXAMPLE_CONFIG_FILENAME), '');
+}
+
+/**
+ * Write the `stackblitz.json` file into the new example.
+ */
+function writeStackBlitzFile(exampleName, examplePath) {
+  const config = {
+    description: titleize(exampleName),
+    files: ['!**/*.d.ts', '!**/*.js', '!**/*.[1,2].*'],
+    tags: [exampleName.split('-')]
+  };
+  fs.writeFileSync(
+      path.resolve(examplePath, STACKBLITZ_CONFIG_FILENAME),
+      JSON.stringify(config, null, 2) + '\n');
+}
+
+/**
+ * Copy all the files from the `sourcePath`, which are not ignored by the `.gitignore` file in the
+ * `EXAMPLES_BASE_PATH`, to the `examplePath`.
+ */
+function copyExampleFiles(sourcePath, examplePath, exampleName) {
+  const gitIgnoreSource = getGitIgnore(sourcePath);
+  const gitIgnoreExamples = getGitIgnore(EXAMPLES_BASE_PATH);
+
+  // Grab the files in the source folder and filter them based on the gitignore rules.
+  const sourceFiles =
+      glob.sync('**/*', {
+            cwd: sourcePath,
+            dot: true,
+            ignore: ['**/node_modules/**', '.git/**', '.gitignore'],
+            mark: true
+          })
+          // Filter out the directories, leaving only files
+          .filter(filePath => !/\/$/.test(filePath))
+          // Filter out files that match the source directory .gitignore rules
+          .filter(filePath => !gitIgnoreSource.ignores(filePath))
+          // Filter out files that match the examples directory .gitignore rules
+          .filter(filePath => !gitIgnoreExamples.ignores(path.join(exampleName, filePath)));
+
+  for (const sourceFile of sourceFiles) {
+    console.log(' - ', sourceFile);
+    const destPath = path.resolve(examplePath, sourceFile)
+    fs.ensureDirSync(path.dirname(destPath));
+    fs.copySync(path.resolve(sourcePath, sourceFile), destPath);
+  }
+}
+
+function getGitIgnore(directory) {
+  const gitIgnoreMatcher = ignore();
+  const gitignoreFilePath = path.resolve(directory, '.gitignore');
+  if (fs.existsSync(gitignoreFilePath)) {
+    const gitignoreFile = fs.readFileSync(gitignoreFilePath, 'utf8');
+    gitIgnoreMatcher.add(gitignoreFile);
+  }
+  return gitIgnoreMatcher;
+}
+
+/**
+ * Convert a kebab-case string to space separated Title Case string.
+ */
+function titleize(input) {
+  return input.replace(
+      /(-|^)(.)/g, (_, pre, char) => `${pre === '-' ? ' ' : ''}${char.toUpperCase()}`);
+}
+
+exports.createEmptyExample = createEmptyExample;
+exports.ensureExamplePath = ensureExamplePath;
+exports.writeExampleConfigFile = writeExampleConfigFile;
+exports.writeStackBlitzFile = writeStackBlitzFile;
+exports.copyExampleFiles = copyExampleFiles;
+exports.titleize = titleize;