比如说，在 PHP 中，我有一堆单元测试。 假设他们需要一些服务才能运行。

理想情况下，我希望我的引导脚本能够:

• 启动这个服务
• 等待服务达到所需状态
• 将控制权交给所选的单元测试框架以运行测试
• 在测试结束时进行清理，适本地优雅地终止服务
• 设置某种方式来捕获服务的所有输出以进行日志记录和调试

我目前正在使用 proc_open() 来初始化我的服务，使用管道机制捕获输出，通过检查输出来检查服务是否达到我需要的状态。

但是此时我很困惑 - 如何在脚本的剩余持续时间内捕获剩余的输出(包括 STDERR)，同时仍然允许我的单元测试运行？

我可以想到一些可能冗长的解决方案，但在花时间调查它们之前，我想知道是否有其他人遇到过这个问题，以及他们找到了哪些解决方案(如果有的话)而不影响响应。

编辑:

这是我在我的 Bootstrap 脚本中初始化的类的简化版本(使用 new ServiceRunner)，供引用:

<?php


namespace Tests;


class ServiceRunner
{
    /**
     * @var resource[]
     */
    private $servicePipes;

    /**
     * @var resource
     */
    private $serviceProc;

    /**
     * @var resource
     */
    private $temp;

    public function __construct()
    {
        // Open my log output buffer
        $this->temp = fopen('php://temp', 'r+');

        fputs(STDERR,"Launching Service.\n");
        $this->serviceProc      = proc_open('/path/to/service', [
            0 => array("pipe", "r"),
            1 => array("pipe", "w"),
            2 => array("pipe", "w"),
        ], $this->servicePipes);

        // Set the streams to non-blocking, so stream_select() works
        stream_set_blocking($this->servicePipes[1], false);
        stream_set_blocking($this->servicePipes[2], false);

        // Set up array of pipes to select on
        $readables = [$this->servicePipes[1], $this->servicePipes[2]);

        while(false !== ($streams = stream_select($read = $readables, $w = [], $e = [], 1))) {
            // Iterate over pipes that can be read from
            foreach($read as $stream) {
                // Fetch a line of input, and append to my output buffer
                if($line = stream_get_line($stream, 8192, "\n")) {
                    fputs($this->temp, $line."\n");
                }

                // Break out of both loops if the service has attained the desired state
                if(strstr($line, 'The Service is Listening' ) !== false) {
                    break 2;
                }

                // If the service has closed one of its output pipes, remove them from those we're selecting on
                if($line === false && feof($stream)) {
                    $readables = array_diff($readables, [$stream]);
                }
            }
        }

        /* SOLUTION REQUIRED SOLUTION REQUIRED SOLUTION REQUIRED SOLUTION REQUIRED */
        /* Set up the pipes to be redirected to $this->temp here */

        register_shutdown_function([$this, 'shutDown']);
    }

    public function shutDown()
    {
        fputs(STDERR,"Closing...\n");
        fclose($this->servicePipes[0]);
        proc_terminate($this->serviceProc, SIGINT);
        fclose($this->servicePipes[1]);
        fclose($this->servicePipes[2]);
        proc_close($this->serviceProc);
        fputs(STDERR,"Closed service\n");

        $logFile = fopen('log.txt', 'w');

        rewind($this->temp);
        stream_copy_to_stream($this->temp, $logFile);

        fclose($this->temp);
        fclose($logFile);
    }
}

最佳答案

假设服务实现为service.sh shell脚本，内容如下:

#!/bin/bash -
for i in {1..4} ; do
  printf 'Step %d\n' $i
  printf 'Step Error %d\n' $i >&2
  sleep 0.7
done

printf '%s\n' 'The service is listening'

for i in {1..4} ; do
  printf 'Output %d\n' $i
  printf 'Output Error %d\n' $i >&2
  sleep 0.2
done

echo 'Done'

该脚本模拟启动过程，打印服务准备就绪的消息，并在启动后打印一些输出。

由于在读取“服务就绪标记”之前您不会继续进行单元测试，所以我认为没有特别的理由异步执行此操作。如果您想在等待服务时运行一些进程(更新 UI 等)，我建议使用具有异步功能的扩展(pthreads、ev、事件等)。

但是，如果只有两件事要异步完成，那为什么不fork一个进程呢？服务可以在父进程中运行，单元测试可以在子进程中启动:

<?php
$cmd = './service.sh';
$desc = [
  1 => [ 'pipe', 'w' ],
  2 => [ 'pipe', 'w' ],
];
$proc = proc_open($cmd, $desc, $pipes);
if (!is_resource($proc)) {
  die("Failed to open process for command $cmd");
}

$service_ready_marker = 'The service is listening';
$got_service_ready_marker = false;

// Wait until service is ready
for (;;) {
  $output_line = stream_get_line($pipes[1], PHP_INT_MAX, PHP_EOL);
  echo "Read line: $output_line\n";
  if ($output_line === false) {
    break;
  }
  if ($output_line == $service_ready_marker) {
    $got_service_ready_marker = true;
    break;
  }

  if ($error_line = stream_get_line($pipes[2], PHP_INT_MAX, PHP_EOL)) {
    $startup_errors []= $error_line;
  }
}

if (!empty($startup_errors)) {
  fprintf(STDERR, "Startup Errors: <<<\n%s\n>>>\n", implode(PHP_EOL, $startup_errors));
}

if ($got_service_ready_marker) {
  echo "Got service ready marker\n";
  $pid = pcntl_fork();
  if ($pid == -1) {
    fprintf(STDERR, "failed to fork a process\n");

    fclose($pipes[1]);
    fclose($pipes[2]);
    proc_close($proc);
  } elseif ($pid) {
    // parent process

    // capture the output from the service
    $output = stream_get_contents($pipes[1]);
    $errors = stream_get_contents($pipes[2]);

    fclose($pipes[1]);
    fclose($pipes[2]);
    proc_close($proc);

    // Use the captured output
    if ($output) {
      file_put_contents('/tmp/service.output', $output);
    }
    if ($errors) {
      file_put_contents('/tmp/service.errors', $errors);
    }

    echo "Parent: waiting for child processes to finish...\n";
    pcntl_wait($status);
    echo "Parent: done\n";
  } else {
    // child process

    // Cleanup
    fclose($pipes[1]);
    fclose($pipes[2]);
    proc_close($proc);

    // Run unit tests
    echo "Child: running unit tests...\n";
    usleep(5e6);
    echo "Child: done\n";
  }
}

示例输出

Read line: Step 1
Read line: Step 2
Read line: Step 3
Read line: Step 4
Read line: The service is listening
Startup Errors: <<<
Step Error 1
Step Error 2
Step Error 3
Step Error 4
>>>
Got service ready marker
Child: running unit tests...
Parent: waiting for child processes to finish...
Child: done
Parent: done

关于php - 将 proc_open() 获取的管道重定向到文件，以处理剩余的过程持续时间，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/43808182/