feat: redirect URLs with duplicate or missing/extra trailing slashes

src/args.ts

@@ -1,6 +1,7 @@
 import { parseArgs, type ParseArgsConfig } from 'node:util';
 
 import { PORTS_CONFIG } from './constants.ts';
+import { isTrailingSlash } from './options.ts';
 import type { HttpHeaderRule, ServerOptions } from './types.d.ts';
 import { intRange, printValue } from './utils.ts';
 
@@ -9,11 +10,9 @@ const PARSE_ARGS_OPTIONS: ParseArgsConfig['options'] = {
 	version: { type: 'boolean' },
 	host: { type: 'string', short: 'h' },
 	port: { type: 'string', short: 'p' },
-	// allow plural as alias to 'ports'
-	ports: { type: 'string' },
+	ports: { type: 'string' }, // alias of 'port'
 	header: { type: 'string', multiple: true },
-	// allow plural as alias to 'header'
-	headers: { type: 'string', multiple: true },
+	headers: { type: 'string', multiple: true }, // alias of 'header'
 	cors: { type: 'boolean' },
 	'no-cors': { type: 'boolean' },
 	gzip: { type: 'boolean' },
@@ -26,6 +25,7 @@ const PARSE_ARGS_OPTIONS: ParseArgsConfig['options'] = {
 	'no-list': { type: 'boolean' },
 	exclude: { type: 'string', multiple: true },
 	'no-exclude': { type: 'boolean' },
+	'trailing-slash': { type: 'string' },
 };
 
 export class CLIArgs {
@@ -160,6 +160,12 @@ export class CLIArgs {
 			options.ext = ext.map((item) => normalizeExt(item));
 		}
 
+		const slash = this.str('trailing-slash');
+		if (slash != null) {
+			if (isTrailingSlash(slash)) options.trailingSlash = slash;
+			else invalid('--trailing-slash', slash);
+		}
+
 		for (const name of this.unknown()) {
 			onError?.(`unknown option '${name}'`);
 		}

src/cli.ts

@@ -202,43 +202,40 @@ export class CLIServer {
 }
 
 export function helpPage() {
-	const spaces = (count = 0) => ' '.repeat(count);
-	const indent = spaces(2);
-	const colGap = spaces(4);
+	const { style: _, brackets: br } = color;
+	const sp = (num = 1) => ' '.repeat(num);
 
 	const section = (heading: string = '', lines: string[] = []) => {
 		const result = [];
-		if (heading.length) result.push(indent + color.style(heading, 'bold'));
-		if (lines.length) result.push(lines.map((l) => indent.repeat(2) + l).join('\n'));
+		if (heading.length) result.push(sp(2) + _(heading, 'bold'));
+		if (lines.length) result.push(lines.map((l) => sp(4) + l).join('\n'));
 		return result.join('\n\n');
 	};
 
-	const optionCols = (options: [string, string][]) => {
-		const col1Width = clamp(Math.max(...options.map((opt) => opt[0].length)), 10, 20);
-		return options.flatMap(([name, help]) => {
-			const col1 = name.padEnd(col1Width) + colGap;
-			const [help1, help2] = help.split('\n');
+	const options = Object.entries(CLI_OPTIONS);
+	const optWidth = clamp(Math.max(...options.map((o) => o[0].length)), 10, 18) + 2;
+	const optionCols = (entries: [string, string][]) =>
+		entries.flatMap((opt) => {
+			const col1 = opt[0].padEnd(optWidth) + sp(2);
+			const [help1, help2] = opt[1].split('\n');
 			const line1 = `${col1}${help1}`;
 			if (help2) {
 				if (line1.length + help2.length <= 76) {
-					return [`${line1} ${color.style(help2, 'gray')}`];
+					return [`${line1} ${_(help2, 'gray')}`];
 				} else {
-					return [line1, spaces(col1.length) + color.style(help2, 'gray')];
+					return [line1, sp(col1.length) + _(help2, 'gray')];
 				}
 			}
 			return [line1];
 		});
-	};
 
 	return [
-		section(
-			`${color.style('servitsy', 'magentaBright bold')} — Local HTTP server for static files`,
-		),
+		section(`${_('servitsy', 'magentaBright bold')} — Local HTTP server for static files`),
 		section('USAGE', [
-			`${color.style('$', 'bold dim')} ${color.style('servitsy', 'magentaBright')} --help`,
-			`${color.style('$', 'bold dim')} ${color.style('servitsy', 'magentaBright')} ${color.brackets('directory')} ${color.brackets('options')}`,
+			`${_('$', 'bold dim')} ${_('servitsy', 'magentaBright')} --help`,
+			`${_('$', 'bold dim')} ${_('servitsy', 'magentaBright')} ${br('directory')} ${br('options')}`,
 		]),
-		section('OPTIONS', optionCols(Object.entries(CLI_OPTIONS))),
+		section('OPTIONS', optionCols(options)),
 	].join('\n\n');
 }
 

src/constants.ts

@@ -1,4 +1,5 @@
-import type { RuntimeOptions } from './types.d.ts';
+import type { RuntimeOptions, TrailingSlash } from './types.d.ts';
+import { getRuntime, intRange } from './utils.ts';
 
 export const HOSTS = {
 	local: ['localhost', '127.0.0.1', '::1'],
@@ -16,15 +17,16 @@ export const SUPPORTED_METHODS = ['GET', 'HEAD', 'OPTIONS', 'POST'];
 export const MAX_COMPRESS_SIZE = 50_000_000;
 
 export const DEFAULT_OPTIONS: Omit<RuntimeOptions, 'root'> = {
-	host: undefined,
-	ports: [8080, 8081, 8082, 8083, 8084, 8085, 8086, 8087, 8088, 8089],
-	gzip: true,
 	cors: false,
+	exclude: ['.*', '!.well-known'],
+	ext: ['.html'],
+	gzip: true,
 	headers: [],
-	list: true,
+	host: getRuntime() === 'webcontainer' ? 'localhost' : undefined,
 	index: ['index.html'],
-	ext: ['.html'],
-	exclude: ['.*', '!.well-known'],
+	list: true,
+	ports: intRange(8080, 8089),
+	trailingSlash: 'auto',
 };
 
 export const CLI_OPTIONS: Record<string, string> = {
@@ -37,6 +39,7 @@ export const CLI_OPTIONS: Record<string, string> = {
 	'--ext': `Set extension(s) used to resolve URLs\n(default: '${DEFAULT_OPTIONS.ext}')`,
 	'--header': `Add custom HTTP header(s) to responses`,
 	'--index': `Set directory index file name(s)\n(default: '${DEFAULT_OPTIONS.index}')`,
+	'--trailing-slash': `Enforce trailing slash in URL path\n('auto' (default) | 'never' | 'always' | 'ignore')`,
 	'--no-exclude': `Disable default file access patterns`,
 	'--no-ext': `Disable default file extensions`,
 	'--no-gzip': `Disable gzip compression of text responses`,

src/fs-utils.ts

@@ -86,3 +86,7 @@ function statsKind(stats: {
 	else if (stats.isFile?.()) return 'file';
 	return null;
 }
+
+export function targetKind({ kind, target }: FSLocation): FSKind {
+	return kind === 'link' && target ? target.kind : kind;
+}