Merge pull request #4 from beyerleinf/dev

Merge development branch

README.md

@@ -2,26 +2,36 @@
 
 > A builder for Azure Function powered by esbuild.
 
-[![Continuous Integration Workflow](https://github.com/beyerleinf/esbuild-azure-functions/actions/workflows/ci.yml/badge.svg)](https://github.com/beyerleinf/esbuild-azure-functions/actions/workflows/ci.yml) [![Codecov](https://img.shields.io/codecov/c/github/beyerleinf/esbuild-azure-functions)](https://app.codecov.io/gh/beyerleinf/esbuild-azure-functions) [![npm](https://img.shields.io/npm/v/esbuild-azue-functions)](https://www.npmjs.com/package/esbuild-azure-functions) [![npm](https://img.shields.io/npm/dm/esbuild-azure-functions)](https://www.npmjs.com/package/esbuild-azure-functions) [![GitHub](https://img.shields.io/github/license/beyerleinf/esbuild-azure-functions)](https://github.com/beyerleinf/esbuild-azure-functions/blob/main/LICENSE)
+[![Continuous Integration Workflow](https://github.com/beyerleinf/esbuild-azure-functions/actions/workflows/ci.yml/badge.svg)](https://github.com/beyerleinf/esbuild-azure-functions/actions/workflows/ci.yml) [![Snyk Vulnerabilities for GitHub Repo](https://img.shields.io/snyk/vulnerabilities/github/beyerleinf/esbuild-azure-functions)](https://github.com/beyerleinf/esbuild-azure-functions) [![Codecov](https://img.shields.io/codecov/c/github/beyerleinf/esbuild-azure-functions)](https://app.codecov.io/gh/beyerleinf/esbuild-azure-functions) [![npm](https://img.shields.io/npm/v/esbuild-azure-functions)](https://www.npmjs.com/package/esbuild-azure-functions) [![npm](https://img.shields.io/npm/dm/esbuild-azure-functions)](https://www.npmjs.com/package/esbuild-azure-functions) [![GitHub](https://img.shields.io/github/license/beyerleinf/esbuild-azure-functions)](https://github.com/beyerleinf/esbuild-azure-functions/blob/main/LICENSE)
 
 This tool is designed to work with Azure Functions written in TypeScript. It uses [esbuild](https://esbuild.github.io/) to create crazy small bundles. This is especially helpful with cold starts and deployment duration.
 
+***Please read this readme to get started. It contains important information.***
+
 # Table of Contents <!-- omit in toc -->
-- [Usage](#usage)
+- [Build](#build)
   - [From the CLI](#from-the-cli)
-- [Programmatically](#programmatically)
+  - [Programmatically](#programmatically)
+- [Watch mode](#watch-mode)
+  - [From the CLI](#from-the-cli-1)
+  - [Programmatically](#programmatically-1)
 - [Config](#config)
   - [`project`](#project)
   - [`entryPoints`](#entrypoints)
   - [`exclude`](#exclude)
   - [`clean`](#clean)
   - [`logLevel`](#loglevel)
   - [`esbuildOptions`](#esbuildoptions)
+  - [`advancedOptions`](#advancedoptions)
+    - [`enableDirnameShim`](#enabledirnameshim)
+- [Common errors](#common-errors)
+  - [`ReferenceError: [__dirname|__filename] is not defined in ES module scope`](#referenceerror-__dirname__filename-is-not-defined-in-es-module-scope)
+  - [`Error: Dynamic require of "xyz" is not supported`](#error-dynamic-require-of-xyz-is-not-supported)
 - [Benchmark](#benchmark)
   - [Package size](#package-size)
   - [Build time](#build-time)
 
-## Usage
+## Build
 
 ### From the CLI
 
@@ -31,7 +41,7 @@ By default, *esbuild-azure-functions* expects a config file called `esbuild-azur
 npx esbuild-azure-functions [-c <config location>]
 ```
 
-## Programmatically
+### Programmatically
 
 Install *esbuild-azure-functions* into your project
 
@@ -57,8 +67,46 @@ main();
 
 ```
 
+## Watch mode
+
+### From the CLI
+
+By default, *esbuild-azure-functions* expects a config file called `esbuild-azure-functions.config.json` in the directory you are running it from. You can specify a different config location with the `-c | --config` flag. Refer to the [Config section](#config) for config options.
+
+```
+npx esbuild-azure-functions --watch [-c <config location>]
+```
+
+### Programmatically
+
+Install *esbuild-azure-functions* into your project
+
+```
+npm i --save-dev esbuild-azure-functions
+```
+
+```ts
+import { watch, BuilderConfigType } from 'esbuild-azure-functions';
+
+const config: BuilderConfigType = {
+  project: process.cwd(),
+  esbuildOptions: {
+    outdir: 'MyCustomOutDir'
+  }
+};
+
+const main = async () => {
+  await watch(config);
+}
+
+main();
+
+```
+
 ## Config
 
+**Important: By default, the file extension of output files is set to `.mjs`. This is because the Azure Functions runtime requires this [see Microsoft Docs](https://docs.microsoft.com/en-us/azure/azure-functions/functions-reference-node?tabs=v2-v3-v4-export%2Cv2-v3-v4-done%2Cv2%2Cv2-log-custom-telemetry%2Cv2-accessing-request-and-response%2Cwindows-setting-the-node-version#ecmascript-modules). You need to change the `scriptFile` property of your *function.json* files accordingly.**
+
 A simple starting config could look like this
 ```json
 {
@@ -75,36 +123,36 @@ A simple starting config could look like this
 **Type:** `string`  
 **Description:** The root folder of the Azure Functions project you want to build.  
 **Example:** `.`  
-**Default:**: `undefined`
+**Default:** `undefined`
 
 ### `entryPoints`
 
 **Required:** no  
 **Type:** `string[]`  
 **Description:** Specify custom entry points if you don't want *esbuild-azure-functions* to search for **index.ts** files in the `project` folder.  
-**Example:**: `[ "my-functions/entry.ts" ]`  
-**Default:**: `undefined`
+**Example:** `[ "my-functions/entry.ts" ]`  
+**Default:** `undefined`
 
 ### `exclude`
 
 **Required:** no  
 **Type:** `string[]`  
 **Description:** Specify directories as glob patterns to exclude when searching for **index.ts** files.  
-**Example:**: `[ "**/utils/**" ]`  
-**Default:**: `undefined`
+**Example:** `[ "**/utils/**" ]`  
+**Default:** `undefined`
 
 ### `clean`
 
 **Required:** no  
 **Type:** `boolean`  
 **Description:** Specify whether *esbuild-azure-functions* should the delete the output directory before building.  
-**Default:**: `false`
+**Default:** `false`
 
 ### `logLevel`
 **Required:** no  
 **Type:** `"off" | "error" | "warn" | "info" | "verbose"`  
 **Description:** Specify the verbosity of log messages.  
-**Default:**: `"error"`
+**Default:** `"error"`
 
 ### `esbuildOptions`
 
@@ -121,10 +169,71 @@ A simple starting config could look like this
   platform: 'node',
   splitting: true,
   format: 'esm',
-  outdir: 'build',
+  outdir: 'dist',
+  outExtension: { '.js': '.mjs' },
 }
 ```
 
+### `advancedOptions`
+**Required:** no  
+**Type:** `object`  
+**Description:** Enable some advanced options depending on your environment
+
+#### `enableDirnameShim`
+**Required:** no  
+**Type:** `boolean`  
+**Description:** Enables a plugin that patches `__dirname` and `__filename` using `import.meta.url` ([see official Node.js docs](https://nodejs.org/docs/latest/api/esm.html#no-__filename-or-__dirname)) at the top of every output file because they are not available in ESM and esbuild doesn't shim them itself.
+
+## Common errors
+
+### `ReferenceError: [__dirname|__filename] is not defined in ES module scope`
+
+This error stems from the fact that `__dirname` and `__filename` are not present in an ESM environment. To fix this, simply set `advancedOptions.enableDirnameShim` to `true` [see config](#enabledirnameshim)
+
+### `Error: Dynamic require of "xyz" is not supported`
+
+This error stems from esbuild not being able to convert CJS requires to ESM imports. This happens mostly (from what I've seen) with Node.js internals (like http, crypto and so on). To fix this issue you have two options:
+1. Turn code splitting of and change the format to `cjs` **(not recommended because it increases the bundle size exponentially)** 
+
+```js
+// build.mjs
+
+await build({
+  project: '.',
+  clean: true,
+  esbuildOptions: {
+    splitting: false,
+    format: 'cjs',
+    outExtension: {}
+  },
+});
+```
+
+2. Use `@esbuild-plugins/esm-externals` with the following setup:
+
+```js
+// build.mjs
+
+import { EsmExternalsPlugin } from '@esbuild-plugins/esm-externals';
+import { build } from 'esbuild-azure-functions';
+import repl from 'repl';
+
+await build({
+  project: '.',
+  exclude: ['**/utils/**'],
+  clean: true,
+  logLevel: 'verbose',
+  esbuildOptions: {
+    target: 'node12',
+    plugins: [
+      EsmExternalsPlugin({ externals: [...repl._builtinLibs] })
+    ],
+  },
+});
+```
+
+If there are other modules causing issues for you, just add them to the `externals` options of `EsmExternalsPlugin`.
+
 ## Benchmark
 
 ### Package size

package.json

@@ -55,12 +55,13 @@
     "@types/glob": "^7.2.0",
     "@types/mocha": "^9.1.0",
     "@types/mock-fs": "^4.13.1",
-    "@types/node": "^14.11.2",
+    "@types/node": "^14.18.12",
     "@types/rimraf": "^3.0.2",
     "@types/sinon": "^10.0.11",
     "c8": "^7.11.0",
     "chai": "^4.3.6",
     "chai-as-promised": "^7.1.1",
+    "chai-exclude": "^2.1.0",
     "gts": "^3.1.0",
     "mocha": "^9.2.0",
     "mocha-multi-reporters": "^1.5.1",

src/cli.ts

@@ -1,13 +1,17 @@
 import { program } from 'commander';
 import { loadConfig, parseConfig } from './lib/config-loader';
-import { build } from './lib/builder';
+import { build, watch } from './lib/builder';
 import { promises as fs } from 'fs';
 
 const main = async () => {
   const { name, version, description } = JSON.parse(await fs.readFile(`${__dirname}/../../package.json`, 'utf8'));
 
   program.name(name).description(description).version(version, '-v, --version');
-  program.requiredOption('-c, --config <file>', 'the config file to use', './esbuild-azure-functions.config.json');
+
+  program
+    .requiredOption('-c, --config <file>', 'the config file to use', './esbuild-azure-functions.config.json')
+    .option('-w, --watch', 'enable watch mode', false);
+
   program.showSuggestionAfterError();
   program.parse();
 
@@ -16,7 +20,11 @@ const main = async () => {
   const file = await loadConfig(options.config);
   const config = parseConfig(file);
 
-  await build(config);
+  if (!options.watch) {
+    await build(config);
+  } else {
+    await watch(config);
+  }
 };
 
 main();

src/index.ts

@@ -1,4 +1,2 @@
-/* c8 ignore start */
 export * from './lib/builder';
 export { BuilderConfigType } from './lib/models';
-/* c8 ignore stop */