Subprocess Spawning: running other files using subprocesses
An example of a subprocess being spawned to run specified files using CLI flags.
import { parseArgs } from "jsr:@std/cli";Grab the file name using the parseArgs function from the standard library. If no file is provided, exit with an error.
import { expandGlob } from "jsr:@std/fs"; const flags = parseArgs(Deno.args, { string: ["file"], default: { file: "", }, }); if (!flags.file) { console.error("No file provided"); Deno.exit(1); }Use expandGlob to find all files matching the provided filename.
const FilesList = await Array.fromAsync( expandGlob(`**/*${flags.file}*`, { root: "." }), ); const files = FilesList.filter((files) => files.name.includes(flags.file));If no files are found, exit with an error.
if (files.length === 0) { console.error("No files found"); Deno.exit(1); }If multiple files are found, exit with an error.
if (files.length > 1) { console.error("Multiple files found"); Deno.exit(1); } const file = files[0];Use the Deno.Command class to create a new command that will run the specified file.
const command = new Deno.Command(Deno.execPath(), { args: [file?.path], });Try to spawn the command and catch any errors that may occur. Wait for the subprocess to finish and log the exit code.
try { const child = command.spawn(); child.ref(); } catch (error) { console.error("Error while running the file: ", error); Deno.exit(4); }Run this example locally using the Deno CLI:
deno run -N --allow-run -R https://docs.deno.com/examples/scripts/subprocess_running_files.ts