This Ruby script checkouts Subversion repositories. If during checkout it encounters two or more externals that point to the same directory, that directory is only downloaded once and symbolic links are created where appropriate, avoiding duplication. It requires the Ruby Subversion bindings.

This is my first Ruby program.

   1  
   2  #!/usr/bin/env ruby
   3  
   4  require 'optparse'
   5  require 'ostruct'
   6  require 'uri'
   7  require 'pathname'
   8  require 'fileutils'
   9  require 'svn/repos'
  10  
  11  class Checkout  
  12  	attr_accessor :url, :pathname, :revision
  13  
  14  	def initialize(url,pathname, revision=nil)
  15  		@url = url
  16  		@pathname = pathname  
  17  		@revision = revision
  18  	end
  19  
  20  	def perform(ctx)
  21  		ctx.checkout @url, @pathname.to_s, @revision, nil, true, true
  22  		proppy = (ctx.propget "svn:externals", @url)[@url]
  23  
  24  		if proppy==nil
  25  			proppy=[]
  26  		else
  27  			lines = proppy.split "\n"
  28  
  29  			lines.map { |line|
  30  				splitted = line.split " "
  31  				sub_path= Pathname.new(splitted.shift)
  32  				sub_url= splitted.pop
  33  				sub_revision= nil
  34  
  35  				if !splitted.empty?
  36  					revnumber_string = splitted.shift.scan(/[0-9]+/).shift
  37  					sub_revision = revnumber_string.to_i
  38  				end
  39  
  40  				Checkout.new(sub_url,@pathname.join(sub_path),sub_revision)		
  41  			}
  42  		end
  43  	end
  44  end  
  45  
  46  def parse_args(args)
  47  	options = OpenStruct.new
  48  
  49  	options.revision = nil;
  50  
  51   	opts = OptionParser.new do |opts|
  52          	opts.banner = "Usage: example.rb URL [PATH]"
  53  
  54          	opts.separator ""
  55          	opts.separator "Valid options:"
  56  
  57          	# Mandatory argument.
  58          	opts.on("-r", "--revision arg","Revision number") do |rev|
  59            		options.revision = rev.to_i
  60  		end
  61  
  62  		opts.on_tail("-h", "--help", "Show this message") do
  63  			puts opts
  64  			exit
  65          	end
  66  	end
  67  
  68  	opts.parse!(args)
  69  
  70  	if args.empty?
  71  		print "Repository URL needed", "\n"
  72  		exit
  73  	end
  74  
  75  	options.url = args.shift
  76  
  77  	if !args.empty?
  78  		options.pathname = Pathname.new(args.shift)
  79  	else
  80  		uri = URI.parse(options.url)
  81  		options.pathname = Pathname.new(uri.path).basename
  82  	end
  83  	
  84  	if !args.empty?
  85  		print "Too many arguments", "\n"
  86  		exit
  87  	end
  88  
  89  	Checkout.new(options.url,options.pathname,options.revision)
  90  end
  91  
  92  
  93  # we parse the args
  94  initial_checkout = parse_args(ARGV)
  95  
  96  # we create a client context
  97  ctx = Svn::Client::Context.new
  98  ctx.add_simple_provider
  99  homedir=ENV['HOME']
 100  ctx.auth_baton[Svn::Core::AUTH_PARAM_CONFIG_DIR] = "#{homedir}/.subversion"
 101  # ctx.auth_baton[Svn::Core::AUTH_PARAM_DEFAULT_USERNAME] = "foouser"
 102  # ctx.auth_baton[Svn::Core::AUTH_PARAM_DEFAULT_PASSWORD] = "foopasswd"
 103  
 104  # we initialize the data structures
 105  checkout_queue = [initial_checkout]
 106  pathname_cache = {}
 107  
 108  # we traverse the tree
 109  while !checkout_queue.empty?
 110  	checkout = checkout_queue.shift
 111  
 112  	cached_path = pathname_cache[checkout.url]
 113  
 114  	if cached_path==nil
 115  		colist = checkout.perform ctx
 116  		colist.each { |co| checkout_queue.push co }
 117  		pathname_cache[checkout.url] = checkout.pathname
 118  
 119  		puts "check out #{checkout.url} -> #{checkout.pathname}"
 120  	else
 121  		relative_path=cached_path.relative_path_from(checkout.pathname.dirname)
 122  		FileUtils.ln_sf(relative_path, checkout.pathname)
 123  
 124  		puts "link #{cached_path} -> #{checkout.pathname}"
 125  	end
 126  end