Ruby OptionParser抛出MissingArgument

Question

让我以两件事作为开始。

1)我已经在Stack Overflow和Google上搜索了这个答案。

2)今天是我第一次尝试和Ruby打交道。

好的，酷。因此，我要做的就是构建一个Ruby脚本，我可以使用它在Homebrew中通过一个命令安装MySQL、PHP、Redis和xdebug。此命令如下所示：

./phpserver.rb --with-php --with-mysql --with-xdebug --with-redis

然而，当我运行上面的命令时，我收到了"missing argument：--with-redis“。如果我通过"--with- Redis =1.0“强制redis的版本，或者如果我没有包含这个选项，这个错误就会消失。

这些选项都不是强制的(是的，我知道脚本还不能处理零选项)。

我完全被难住了，如果有一个明显的答案，你想链接到我，那是很好的。我为我缺乏Ruby知识而道歉，这是一个辅助项目，可以帮助我更好地了解Ruby。

下面是我的脚本：

#!/usr/bin/ruby
prefix = `brew --prefix`.gsub("\n", "");
$LOAD_PATH << prefix+"/Library/Homebrew/"

# Required scripts
require 'optparse'
require 'global'

# Handle Ctrl+C
trap('INT') {
  opoo "Installation failed. Please try again!"
  exit!
}

# Start big try statement
begin

# Options
options = {}
OptionParser.new do |opts|
  banner = "\nUsage: phpserver.rb [options]\n\n"

  opts.banner = banner
  opts.on("--with-mysql=VERSION", "Install MySQL with VERSION",
          "Run `brew versions mysql` to see available versions.") do |v|
    options[:mysql] = v
  end
  opts.on("--with-php", "Install PHP") do |v|
    options[:php] = v
  end
  opts.on("--with-xdebug", "Install xdebug for PHP debugging") do |v|
    options[:xdebug] = v
  end
  opts.on("--with-redis=VERSION", "Install Redis with VERSION",
          "Run `brew versions redis` to see available versions.") do |v|
    options[:redis] = v
  end
  opts.on_tail("-h", "--help", "Show this message") do
    puts opts
    puts "\n"
    exit
  end
end.parse!

# Need to run brew update first?
ohai "Making sure Homebrew is up to do."
versions = `brew versions --compact a2ps`
if versions.include? "Please `brew install git` first"
  ohai "Need to install Git before the script can run; we'll do that for you."
  system 'brew install git'

  ohai "Now we need to pull down the Homebrew repository, we'll do that for you as well."
  system 'brew update'
elsif versions.include? "Please `brew update"
  ohai "Homebrew needs to be updated, we'll take care of that."
  system 'brew update'
end

# Tap them kegs!
if !File.directory?("#{prefix}/Library/Taps/josegonzalez-php")
  ohai "Tapping josegonzalez/homebrew-php"
  if system 'brew tap josegonzalez/homebrew-php'
    oh1 "Success!"
  else
    opoo "Failed to tap the keg. Please report this."
  end
else
  oh1 "The josegonzalez/homebrew-php keg has already been tapped. Continuing..."
end

# Installing MySQL?
if options[:mysql] != nil
  ohai "Installing MySQL."

  revert = false
  command = false
  if options[:mysql] != true
    versions = `brew versions mysql`

    errors = []
    versions.each do |version|
      if version.start_with? options[:mysql]
        revert = true
        command = version.gsub(options[:mysql], "").gsub(prefix+"/", "").strip!
        break
      else
        errors << "- "+version
      end
    end

    if command == false
      error = "Invalid MySQL version. The available versions for MySQL are:\n\n"
      error += errors.join()
      opoo error
    else
      %x(cd #{prefix} && #{command})
    end
  end

  system 'brew install mysql'

  if revert
    command = command.split(" ").last
    %x(cd #{prefix} && #{command})
  end
end

# Installing PHP?
if options[:php] != nil
  ohai "Installing PHP."

  install = 'brew install php';
  if options[:mysql] != nil
    install += ' --with-mysql';
  end
  if options[:php] == true or options[:php].to_f < 5.4
    install += ' --with-suhosin';
  end

  system install
end

# Installing xdebug?
if options[:xdebug] != nil
  ohai "Installing xdebug."
  system 'brew install xdebug-php'
end

# Installing Redis?
if options[:redis] != nil
  ohai "Installing Redis."
  system 'brew install redis'
end

rescue OptionParser::NeedlessArgument
  opoo "Invalid arguments. Run `./phpserver.php -h` for help."
rescue StandardError => message
  if !["exit"].include? message
    opoo message
  end
end 

Answer 1

你也应该收到关于--with-mysql缺少参数的投诉。从fine manual

Long style开关：

指定采用强制参数、可选参数或无参数的长型开关。它是一个以下形式的字符串：

"--switch =强制“或”--switch强制“”--switch=可选“"--switch”

所以你想使用--with-mysql[=VERSION]和类似的东西：

opts.on("--with-mysql[=VERSION]", "Install MySQL with VERSION",
        "Run `brew versions mysql` to see available versions.") do |v|
  options[:mysql] = v
end
#...
opts.on("--with-redis[=VERSION]", "Install Redis with VERSION",
        "Run `brew versions redis` to see available versions.") do |v|
  options[:redis] = v
end

如果你说--with-redis就会得到options[:redis] = nil，如果你说--with-redis=1.0就会得到options[:redis] = '1.0'。