Migrate nested SVN repositories to Git

Gemfile

source :rubygems

gem "svn2git", "~>2.2"

svn2git-recursive.rb

#!/usr/bin/env ruby

# Migrate an SVN project to Git. The repository can contain nested repositories.
# Run this script from the directory that you want to contain the git repository.
# It will create an authors transform file if one does not exists.

require "bundler"
Bundler.setup

require "fileutils"
require "svn2git"

def warn(str, padding = "")
  $stderr.puts "#{padding}\033[32m#{str}\033[0m\n"
end

def error(str, padding = "")
  $stderr.puts "#{padding}\033[31m#{str}\033[0m\n"
end

def abort(str)
  error(str)
  Process.exit 2
end


class SVN2GitRecursive
  attr_reader :failures, :root, :svn_root, :authors
  def initialize(checked_out_svn, root = Dir.pwd, opts = {})
    opts, root = root, opts if root.is_a?(Hash)
    root = Dir.pwd if root.is_a?(Hash)
    @popd_stack = []
    @failures   = []
    @root       = root
    self.svn_root    = checked_out_svn
    @verbose  = opts[:verbose] || ""
    @authors = File.expand_path("authors-transform.txt")
    unless File.exists?(@authors)
      pushd(checked_out_svn) do
        system %Q{svn log -q | awk -F '|' '/^r/ {sub("^ ", "", $2); sub(" $", "", $2); print $2" = "$2" <"$2">"}' | sort -u > #{@authors}}
      end
      abort "please edit #{@authors} to include the names and e-mail addresses of all contributors"
    end
    FileUtils.mkdir_p(File.join(root, "repos"))
    migrate(checked_out_svn)
  end

  def svn_root=(svnr)
    @svn_root = svnr
    @svn_root += "/" unless @svn_root[-1] == "/"
  end

  def svn_url
    return @svn_url if @svn_url
    @svn_url = svn_url_for(svn_root)
    unless @svn_url
      raise ConfigurationError.new("#{checked_out_svn.path} is not a valid svn repository or does not include a URL attribute")
    end
  end

  def svn_url_for(path)
    pushd(path)
    svn_url = `svn info`.split("\n").find{|s| s.start_with?("URL:") }
    svn_url &&= svn_url.split("URL:",2)[-1].strip
    popd
    svn_url
  end

  def pushd(path)
    @popd_stack.push(Dir.pwd)
    FileUtils.chdir(path)
    if block_given?
      begin
        yield
      ensure
        popd
      end
    end
  end

  def popd
    raise "popd stack is empty" if @popd_stack.empty?
    FileUtils.chdir(@popd_stack.pop)
  end

  def migrated?(dir)
    return false if dir == self.svn_root
    File.exists?(File.join(git_path(dir), ".git"))
  end

  def migrate!(projdir, args = "")
    path = git_path(projdir)
    warn "  migrate #{projdir} to #{path}"
    FileUtils.mkdir_p(path)
    succ = pushd(path) do
      url = svn_url_for(projdir)
      system("svn2git #{url} --authors #{authors} #{@verbose} #{args}")
    end
    unless succ
      failures << projdir
      error "failed to migrate #{projdir}"
      FileUtils.rm_rf(path)
    end
    succ
  end

  def git_path(projdir)
    return File.join(@root, "repos") if projdir == self.svn_root || "#{projdir}/" == self.svn_root
    File.join(@root, "repos", projdir.split(self.svn_root, 2)[-1].gsub("/", "_"))
  end

  def migrate(projdir, level = 0)
    return true if migrated?(projdir)
    warn "migrating #{projdir}"
    contents = Dir[File.join(projdir, "*")]
    if contents.map{|c| File.basename(c) }.include?("trunk")
      migrate!(projdir, "--no-minimize-url")
    elsif Dir[File.join(projdir, "**/trunk")].empty?
      warn "assuming #{projdir} is trunk"
      migrate!(projdir, "--no-minimize-url --rootistrunk")
    else
      contents.each { |subproj| migrate(subproj) }
    end
  end
end


verbose = ARGV.delete("-v") ? "-v" : ""
abort "usage: #{File.basenaem($0)} [-v] checked_out_svn_repo" if ARGV.empty? || !File.exists(ARGV[0])

migration = SVN2GitRecursive.new(ARGV[0], :verbose => verbose)
unless migration.failures.empty?
  abort "failed to migrate: #{migration.failures.join(", ")}"
end