Lazy load commands

src/bin/cli.ts

@@ -2,7 +2,7 @@
 import * as clc from "colorette";
 import { markedTerminal } from "marked-terminal";
 import { marked } from "marked";
 marked.use(markedTerminal() as any);
 
 import { CommanderStatic } from "commander";
 import * as fs from "node:fs";
@@ -18,8 +18,8 @@
 import { enableExperimentsFromCliEnvVariable } from "../experiments";
 import { fetchMOTD } from "../fetchMOTD";
 
 export function cli(pkg: any) {
   const updateNotifier = updateNotifierPkg({ pkg });
 
   const args = process.argv.slice(2);
   let cmd: CommanderStatic;
@@ -34,7 +34,7 @@
 
   logger.debug("-".repeat(70));
   logger.debug("Command:      ", process.argv.join(" "));
   logger.debug("CLI Version:  ", pkg.version);
   logger.debug("Platform:     ", process.platform);
   logger.debug("Node Version: ", process.version);
   logger.debug("Time:         ", new Date().toString());
@@ -54,7 +54,7 @@
     }
 
     if (code > 0 && process.stdout.isTTY) {
       const lastError = configstore.get("lastError") || 0;
       const timestamp = Date.now();
       if (lastError > timestamp - 120000) {
         let help;
@@ -84,7 +84,7 @@
       const updateMessage =
         `Update available ${clc.gray("{currentVersion}")} → ${clc.green("{latestVersion}")}\n` +
         `To update to the latest version using ${installMethod}, run\n${clc.cyan(updateCommand)}\n` +
         `For other CLI management options, visit the ${marked(
           "[CLI documentation](https://firebase.google.com/docs/cli#update-cli)",
         )}`;
       // `defer: true` would interfere with commands that perform tasks (emulators etc.)
@@ -109,7 +109,20 @@
 
   if (!handlePreviewToggles(args)) {
     // determine if there are any arguments. if not, display help
-    if (!args.length) {
+    if (!args.length || args[0] === "help") {
+      const seen = new Set();
+      const loadAll = (obj: any) => {
+        if (seen.has(obj)) return;
+        seen.add(obj);
+        for (const [key, value] of Object.entries(obj)) {
+          if (typeof value === "function" && (value as any).load) {
+            (value as any).load();
+          } else if (typeof value === "object" && value !== null && !Array.isArray(value) && key !== "cli") {
+             loadAll(value);
+          }
+        }
+      };
+      loadAll(client);
       client.cli.help();
     } else {
       cmd = client.cli.parse(process.argv);

src/commands/index.ts

@@ -1,20 +1,36 @@
 import * as experiments from "../experiments";
+import { Command } from "../command";
+
 /**
  * Loads all commands for our parser.
  */
 export function load(client: any): any {
   function loadCommand(name: string) {
     const t0 = process.hrtime.bigint();
-    const { command: cmd } = require(`./${name}`);
-    cmd.register(client);
-    const t1 = process.hrtime.bigint();
-    const diffMS = (t1 - t0) / BigInt(1e6);
-    if (diffMS > 75) {
-      // NOTE: logger.debug doesn't work since it's not loaded yet. Comment out below to debug.
-      // console.error(`Loading ${name} took ${diffMS}ms`);
-    }
 
-    return cmd.runner();
+    const load = () => {
+      const { command: cmd } = require(`./${name}`);
+      cmd.register(client);
+      return cmd.runner();
+    };
+
+    const runner = async (...args: any[]) => {
+      const run = load();
+      return run(...args);
+    };
+
+    // Store the load function on the runner so we can trigger it without running.
+    (runner as any).load = () => {
+      const tStart = process.hrtime.bigint();
+      require(`./${name}`).command.register(client);
+      const tEnd = process.hrtime.bigint();
+      const diff = (tEnd - tStart) / BigInt(1e6);
+      if (diff > 75) {
+         // console.error(`Loading ${name} took ${diff}ms`);
+      }
+    };
+
+    return runner;
   }
 
   const t0 = process.hrtime.bigint();

src/index.ts

@@ -75,9 +75,32 @@ const RENAMED_COMMANDS: Record<string, string> = {
 
 // Default handler, this is called when no other command action matches.
 program.action((_, args) => {
+  const cmd = args[0];
+  const keys = cmd.split(":");
+  let obj = client;
+  let hit = true;
+  for (const key of keys) {
+    if (!obj || typeof obj !== "object") {
+      hit = false;
+      break;
+    }
+    const nextKey = Object.keys(obj).find((k) => k.toLowerCase() === key.toLowerCase());
+    if (!nextKey) {
+      hit = false;
+      break;
+    }
+    obj = (obj as any)[nextKey];
+  }
+
+  if (hit && typeof obj === "function" && (obj as any).load) {
+    (obj as any).load();
+    // eslint-disable-next-line @typescript-eslint/no-explicit-any
+    (client.cli as any).parse(process.argv);
+    return;
+  }
+
   useConsoleLoggers();
 
-  const cmd = args[0];
   logger.error(clc.bold(clc.red("Error:")), clc.bold(cmd), "is not a Firebase command");
 
   if (RENAMED_COMMANDS[cmd]) {