NodeJS在readline中获得颜色

时间:2019-03-17 14:28:58

标签: node.js console readline

我有一个NodeJS应用程序,需要使用spawn执行一些命令,我​​正在读取输出以供以后使用readline正常处理。

但是我还需要获取文本的颜色,例如: 当执行另一个使用Node.js模块的chalk脚本时。

这怎么完成?

到目前为止,这是我的代码:

const spawn = require('child_process').spawn;
const readline = require('readline');

let myCommand = spawn(<command>, [<args...>], { cwd: dirPath });

readline.createInterface({
  input    : myCommand.stdout,
  terminal : true
}).on('line', (line) => handleOutput(myCommand.pid, line));

readline.createInterface({
  input    : myCommand.stderr,
  terminal : true
}).on('line', (line) => handleErrorOutput(myCommand.pid, line));

myCommand.on('exit', (code) => {
  // Do more stuff ..
});

更新

Amr K. Aly's answer确实可以工作,但是当执行外部NodeJS脚本时,它返回空色。

我的代码(index.js)

const spawn = require('child_process').spawn;
const readline = require('readline');

let myCommand = spawn('node', ['cmd.js']);

readline.createInterface({
  input: myCommand.stdout,
  terminal: true
}).on('line', (line) => handleOutput(myCommand.pid, line));

readline.createInterface({
  input: myCommand.stderr,
  terminal: true
}).on('line', (line) => handleErrorOutput(myCommand.pid, line));

myCommand.on('exit', (code) => {
  // Do more stuff ..
});

function handleErrorOutput(obj, obj2) {}

function handleOutput(obj, line, a, b, c) {
  //PRINT TEXT WITH ANSI FORMATING
  console.log(line);

  //REGEX PATTERN TO EXTRACT COLOR
  var options = Object.assign({
    onlyFirst: false
  });

  const pattern = [
    '[\\u001B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[-a-zA-Z\\d\\/#&.:=?%@~_]*)*)?\\u0007)',
    '(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PR-TZcf-ntqry=><~]))'
  ].join('|');

  var regex = new RegExp(pattern, options.onlyFirst ? undefined : 'g');
  var ansiColor = (line.match(regex));

  //PRINT EXTRACTED ANSI
  console.log("ANSI COLOR CODE :");
  console.log(ansiColor);
}

cmd.js

const chalk = require('chalk');

console.log(chalk.blue('Blue Hello world!'));
console.log(chalk.green('green Hello world!'));
console.log(chalk.red('red Hello world!'));

我的结果

Index.js result

1 个答案:

答案 0 :(得分:1)

问题:

打印回读取的文本流时看不到颜色,因为您已将createInterface中的terminal选项设置为true。这将导致createInterface()不返回ANSI / VT100编码。

解决方案:

terminal选项需要设置为false,以便文本将使用ANSI / VT100进行编码 从Nodejs文档中: terminal <boolean> true if the input and output streams should be treated like a TTY, and have ANSI/VT100 escape codes written to it. Default: checking isTTY on the output stream upon instantiation.参见readline.createInterface(options) documentation

readline.createInterface({
input: myCommand.stdout,
terminal: true//<== NEEDS TO BE SET TO FALSE 
}).on('line', (line) => handleOutput(myCommand.pid, line));

terminal设置为false后,返回的文本将进行ANSI / VT100编码。然后,您需要提取与颜色相关的ANSI / VT100编码,并将其更改为所需的任何颜色格式。

请参阅修改后的代码,并在下面的输出中添加正则表达式以提取ANSI颜色代码。您需要添加自己的逻辑来处理ANSI转义的颜色。

const spawn = require('child_process').spawn;
const readline = require('readline');
const chalk = require('chalk');

 //Testing on windows 10
let myCommand = spawn(process.env.comspec, ['/c', 'echo ' + chalk.red('Hello world!'), ], {
    // cwd: dirPath
});

readline.createInterface({
    input: myCommand.stdout,
    terminal: false
}).on('line', (line) => handleOutput(myCommand.pid, line));

readline.createInterface({
    input: myCommand.stderr,
    terminal: false
}).on('line', (line) => handleErrorOutput(myCommand.pid, line));

myCommand.on('exit', (code) => {
    // Do more stuff ..
});

function handleErrorOutput(obj, obj2) {}

function handleOutput(obj, line) {

    //PRINT TEXT WITH ANSI FORMATING
    console.log(line);

    //REGEX PATTERN TO EXTRACT COLOR
    var options = Object.assign({
        onlyFirst: false
    });

    const pattern = [
        '[\\u001B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[-a-zA-Z\\d\\/#&.:=?%@~_]*)*)?\\u0007)',
        '(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PR-TZcf-ntqry=><~]))'
    ].join('|');

    var regex = new RegExp(pattern, options.onlyFirst ? undefined : 'g');
    var ansiColor = (line.match(regex));

    //PRINT EXTRACTED ANSI
    console.log("ANSI COLOR CODE :");
    console.log(ansiColor);
}

上面代码的输出:

Output for code above:

编辑:

粉笔将自动检测您是否正在写入TTY或终端不支持颜色,并禁用颜色。您可以通过设置环境变量FORCE_COLOR=1或通过传递--color作为参数来强制执行此操作。

如果您将代码从下面的代码段更改为该行,Chalk应该正确添加样式。

let myCommand = spawn('node', ['test.js', '--color', ], {


}); 

输出:

Code Output