feat: support same allowList options as webpack-node-externals (#50)

Co-authored-by: Andrew Sprouse <[email protected]>

esbuild-node-externals/README.md

@@ -80,7 +80,7 @@ Make package.json `optionalDependencies` external.
 
 #### `options.allowList` (default to `[]`)
 
-Specify packages which are not marked as external. They will be included in the bundle.
+An array for the externals to allow, so they will be included in the bundle. Can accept exact strings ('module_name'), regex patterns (/^module_name/), or a function that accepts the module name and returns whether it should be included.
 
 #### `options.allowWorkspaces` (default to `false`)
 

esbuild-node-externals/src/index.ts

@@ -1,14 +1,19 @@
 import type { Plugin } from 'esbuild';
 
-import { findPackagePaths, findDependencies } from './utils';
+import {
+  findPackagePaths,
+  findDependencies,
+  AllowList,
+  createAllowPredicate,
+} from './utils';
 
 export interface Options {
   packagePath?: string | string[];
   dependencies?: boolean;
   devDependencies?: boolean;
   peerDependencies?: boolean;
   optionalDependencies?: boolean;
-  allowList?: string[];
+  allowList?: AllowList;
   allowWorkspaces?: boolean;
 }
 
@@ -18,7 +23,6 @@ export const nodeExternalsPlugin = (paramsOptions: Options = {}): Plugin => {
     devDependencies: true,
     peerDependencies: true,
     optionalDependencies: true,
-    allowList: [] as string[],
     allowWorkspaces: false,
     ...paramsOptions,
     packagePath:
@@ -27,6 +31,9 @@ export const nodeExternalsPlugin = (paramsOptions: Options = {}): Plugin => {
         : (paramsOptions.packagePath as string[] | undefined),
   };
 
+  const allowPredicate =
+    options.allowList && createAllowPredicate(options.allowList);
+
   const nodeModules = findDependencies({
     packagePaths: options.packagePath
       ? options.packagePath
@@ -35,7 +42,7 @@ export const nodeExternalsPlugin = (paramsOptions: Options = {}): Plugin => {
     devDependencies: options.devDependencies,
     peerDependencies: options.peerDependencies,
     optionalDependencies: options.optionalDependencies,
-    allowList: options.allowList,
+    allowPredicate,
     allowWorkspaces: options.allowWorkspaces,
   });
 
@@ -45,7 +52,7 @@ export const nodeExternalsPlugin = (paramsOptions: Options = {}): Plugin => {
       // On every module resolved, we check if the module name should be an external
       build.onResolve({ namespace: 'file', filter: /.*/ }, (args) => {
         // To allow allowList to target sub imports
-        if (options.allowList.includes(args.path)) {
+        if (allowPredicate?.(args.path)) {
           return null;
         }
 

esbuild-node-externals/src/utils.ts

@@ -2,6 +2,20 @@ import path from 'path';
 import fs from 'fs';
 import findUp from 'find-up';
 
+export type AllowPredicate = (path: string) => boolean;
+export type AllowList = (string | RegExp)[] | AllowPredicate;
+
+export const createAllowPredicate = (allowList: AllowList): AllowPredicate => {
+  return typeof allowList === 'function'
+    ? allowList
+    : (path: string) =>
+        Boolean(
+          allowList.find((pattern) =>
+            typeof pattern === 'string' ? path === pattern : pattern.test(path)
+          )
+        );
+};
+
 /**
  * Determines if the `child` path is under the `parent` path.
  */
@@ -43,7 +57,10 @@ export const findPackagePaths = (): string[] => {
   return packagePaths;
 };
 
-function getDependencyKeys(map: Record<string, string> = {}, allowWorkspaces: boolean = false): string[] {
+function getDependencyKeys(
+  map: Record<string, string> = {},
+  allowWorkspaces: boolean = false
+): string[] {
   if (!map) {
     return [];
   }
@@ -63,7 +80,7 @@ export const findDependencies = (options: {
   devDependencies: boolean;
   peerDependencies: boolean;
   optionalDependencies: boolean;
-  allowList: string[];
+  allowPredicate?: AllowPredicate | undefined;
   allowWorkspaces: boolean;
 }): string[] => {
   const packageJsonKeys = [
@@ -85,11 +102,15 @@ export const findDependencies = (options: {
       );
     }
 
-    return packageJsonKeys
-      // Automatically exclude keys for interconnected yarn workspaces.
-      .map((key) => getDependencyKeys(packageJson[key], options.allowWorkspaces))
-      .flat(1)
-      .filter((packageName) => !options.allowList.includes(packageName));
+    const packageNames = packageJsonKeys
+      .map((key) =>
+        getDependencyKeys(packageJson[key], options.allowWorkspaces)
+      )
+      .flat(1);
+    const { allowPredicate } = options;
+    return allowPredicate
+      ? packageNames.filter((packageName) => !allowPredicate(packageName))
+      : packageNames;
   });
 
   return data.flat(1);