Added documentation on cli

toolbox/cli/command.ts

@@ -0,0 +1,40 @@
+import {
+  CLI,
+  CLIAsyncCommand,
+  CLICommand,
+  displayHelp,
+} from "$root/toolbox/cli/help.ts";
+
+/**
+ * Run the command given by arguments.
+ * @param commands The given arguments.
+ * @param cli The CLI (sub-)configuration object.
+ * @returns The command or the help if commands are not valid.
+ */
+export function runCommand(
+  commands: Array<string | number>,
+  cli: CLI,
+): never | {
+  command: CLICommand | CLIAsyncCommand;
+  args: Array<string | number>;
+} {
+  if (commands.length == 0) {
+    displayHelp(cli, `No command provided.`);
+  }
+
+  const command = commands.shift()!.toString();
+
+  if (cli[command] == undefined) {
+    displayHelp(cli, `Command "${command}" doesn't exist.`);
+  }
+
+  if (typeof cli[command] == "object") {
+    return runCommand(commands, cli[command]);
+  }
+
+  if (cli[command].length != commands.length) {
+    displayHelp(cli[command], `Wrong usage of command "${command}".`);
+  }
+
+  return { command: cli[command], args: commands };
+}

toolbox/cli/help.ts

@@ -0,0 +1,70 @@
+export type CLICommand = (...args: Array<string>) => void;
+export type CLIAsyncCommand = (...args: Array<string>) => Promise<void>;
+export interface CLI {
+  [command: string]: CLI | CLICommand | CLIAsyncCommand;
+}
+
+/**
+ * Display the help message for the CLI.
+ * @param cli The CLI (sub-)configuration object.
+ * @param errorMessage The error message to display.
+ */
+export function displayHelp(
+  cli: CLI | CLICommand | CLIAsyncCommand,
+  errorMessage?: string,
+): never {
+  const loggingFunction = errorMessage ? console.error : console.log;
+  if (errorMessage) {
+    console.error(errorMessage);
+  }
+
+  if (typeof cli == "function") {
+    loggingFunction("Usage:");
+    displayFunctionHelp(cli, loggingFunction);
+  } else {
+    loggingFunction("Commands:");
+    displayObjectHelp(cli, loggingFunction);
+  }
+
+  Deno.exit(errorMessage ? 1 : 0);
+}
+
+/**
+ * Display object help recursivelly.
+ * @param cli The CLI (sub-)configuration object.
+ * @param loggingFunction The logging function to use.
+ * @param level The tab level.
+ */
+function displayObjectHelp(
+  cli: CLI,
+  loggingFunction: typeof console.log,
+  level: number = 1,
+) {
+  for (const [key, value] of Object.entries(cli)) {
+    if (typeof value == "function") {
+      displayFunctionHelp(value, loggingFunction, level);
+    } else {
+      loggingFunction(`${" ".repeat(level * 2)}${key}`);
+      displayObjectHelp(value, loggingFunction, level + 1);
+    }
+  }
+}
+
+/**
+ * Display function help.
+ * @param cli The CLI function.
+ * @param loggingFunction The logging function to use.
+ * @param level The tab level.
+ */
+function displayFunctionHelp(
+  cli: CLICommand | CLIAsyncCommand,
+  loggingFunction: typeof console.log,
+  level: number = 1,
+) {
+  const command = cli.name;
+  const matched = cli.toString().match(/(?<=^\()[^\)]+(?=\))/);
+  const args = matched?.[0].split(",").map((arg) => `<${arg.trim()}>`);
+  loggingFunction(
+    `${" ".repeat(level * 2)}${command} ${args?.join(" ") ?? ""}`,
+  );
+}

toolbox/cli/main.ts

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+import { parseArgs, ParseOptions } from "@std/cli/parse-args";
+import { runCommand } from "$root/toolbox/cli/command.ts";
+import { CLI } from "$root/toolbox/cli/help.ts";
+
+/**
+ * Runs the CLI.
+ * @param cli The CLI configuration object.
+ * @param argSpec The Parse options for args.
+ */
+export function main(cli: CLI, argSpec: ParseOptions) {
+  const argv = parseArgs(Deno.args, argSpec);
+  const { command, args } = runCommand(argv._, cli);
+  command(...args.map((element) => element.toString()));
+}