安装

npm install execa

使用

• Promise 接口

import {execa} from 'execa';

const {stdout} = await execa('echo', ['unicorns']);
console.log(stdout);
//=> 'unicorns'

• 基本

import {$} from 'execa';

const branch = await $`git branch --show-current`;
await $`dep deploy --branch=${branch}`;

• 多个参数

import {$} from 'execa';

const args = ['unicorns', '&', 'rainbows!'];
const {stdout} = await $`echo ${args}`;
console.log(stdout);
//=> 'unicorns & rainbows!'

• 有选项

import {$} from 'execa';

await $({stdio: 'inherit'})`echo unicorns`;
//=> 'unicorns'

• 共享选项

import {$} from 'execa';

const $$ = $({stdio: 'inherit'});

await $$`echo unicorns`;
//=> 'unicorns'

await $$`echo rainbows`;
//=> 'rainbows'

• 详细模式

> node file.js
unicorns
rainbows

> NODE_DEBUG=execa node file.js
[16:50:03.305] echo unicorns
unicorns
[16:50:03.308] echo rainbows
rainbows

• 将输出重定向到文件

import {execa} from 'execa';

// Similar to `echo unicorns > stdout.txt` in Bash
await execa('echo', ['unicorns']).pipeStdout('stdout.txt');

// Similar to `echo unicorns 2> stdout.txt` in Bash
await execa('echo', ['unicorns']).pipeStderr('stderr.txt');

// Similar to `echo unicorns &> stdout.txt` in Bash
await execa('echo', ['unicorns'], {all: true}).pipeAll('all.txt');

• 重定向文件中的输入

import {execa} from 'execa';

// Similar to `cat < stdin.txt` in Bash
const {stdout} = await execa('cat', {inputFile: 'stdin.txt'});
console.log(stdout);
//=> 'unicorns'

• 保存子进程的输出并通过管道传递

import {execa} from 'execa';

const {stdout} = await execa('echo', ['unicorns']).pipeStdout(process.stdout);
// Prints `unicorns`
console.log(stdout);
// Also returns 'unicorns'

• 管道多工序

import {execa} from 'execa';

// Similar to `echo unicorns | cat` in Bash
const {stdout} = await execa('echo', ['unicorns']).pipeStdout(execa('cat'));
console.log(stdout);
//=> 'unicorns'

• 处理错误

import {execa} from 'execa';

// Catching an error
try {
	await execa('unknown', ['command']);
} catch (error) {
	console.log(error);
	/*
	{
		message: 'Command failed with ENOENT: unknown command spawn unknown ENOENT',
		errno: -2,
		code: 'ENOENT',
		syscall: 'spawn unknown',
		path: 'unknown',
		spawnargs: ['command'],
		originalMessage: 'spawn unknown ENOENT',
		shortMessage: 'Command failed with ENOENT: unknown command spawn unknown ENOENT',
		command: 'unknown command',
		escapedCommand: 'unknown command',
		stdout: '',
		stderr: '',
		failed: true,
		timedOut: false,
		isCanceled: false,
		killed: false
	}
	*/
}

• 优雅终止，使用 SIGTERM，2 秒后，用 SIGKILL 杀死它。

const subprocess = execa('node');

setTimeout(() => {
	subprocess.kill('SIGTERM', {
		forceKillAfterTimeout: 2000
	});
}, 1000);