Sync state with hosts file in blocks

lib/vagrant-hostmanager/hosts_file.rb

@@ -19,7 +19,7 @@ def update_guest(machine)
  # download and modify file with Vagrant-managed entries
  file = @global_env.tmp_path.join("hosts.#{machine.name}")
  machine.communicate.download(realhostfile, file)
- update_file(file, machine)
+ update_file(file, machine, false)
 
  # upload modified file and remove temporary file
  machine.communicate.upload(file, '/tmp/hosts')
@@ -55,43 +55,27 @@ class << self
 
  private
 
- def update_file(file, resolving_machine=nil)
- # build array of host file entries from Vagrant configuration
- entries = []
- destroyed_entries = []
- ids = []
- get_machines.each do |name, p|
- if @provider == p
- machine = @global_env.machine(name, p)
- host = machine.config.vm.hostname || name
- id = machine.id
- ip = get_ip_address(machine, resolving_machine)
- aliases = machine.config.hostmanager.aliases.join(' ').chomp
- if id.nil?
- destroyed_entries << "#{ip}\t#{host} #{aliases}"
- else
- entries << "#{ip}\t#{host} #{aliases}\t# VAGRANT ID: #{id}\n"
- ids << id unless ids.include?(id)
- end
- end
- end
+ def update_file(file, resolving_machine = nil, include_id = true)
+ file = Pathname.new(file)
+ new_file_content = update_content(file.read, resolving_machine, include_id)
+ file.open('w') { |io| io.write(new_file_content) }
+ end
 
- tmp_file = Tempfile.open('hostmanager', @global_env.tmp_path, 'a')
- begin
- # copy each line not managed by Vagrant
- File.open(file).each_line do |line|
- # Eliminate lines for machines that have been destroyed
- next if destroyed_entries.any? { |entry| line =~ /^#{entry}\t# VAGRANT ID: .*/ }
- tmp_file << line unless ids.any? { |id| line =~ /# VAGRANT ID: #{id}/ }
- end
+ def update_content(file_content, resolving_machine, include_id)
+ id = include_id ? " id: #{read_or_create_id}" : ""
+ header = "## vagrant-hostmanager-start#{id}\n"
+ footer = "## vagrant-hostmanager-end\n"
+ body = get_machines
+ .map { |machine| get_hosts_file_entry(machine, resolving_machine) }
+ .join
+ get_new_content(header, footer, body, file_content) 
+ end
 
- # write a line for each Vagrant-managed entry
- entries.each { |entry| tmp_file << entry }
- ensure
- tmp_file.close
- FileUtils.cp(tmp_file, file)
- tmp_file.unlink
- end
+ def get_hosts_file_entry(machine, resolving_machine)
+ ip = get_ip_address(machine, resolving_machine)
+ host = machine.config.vm.hostname || machine.name
+ aliases = machine.config.hostmanager.aliases.join(' ').chomp
+ "#{ip}\t#{host} #{aliases}\n"
  end
 
  def get_ip_address(machine, resolving_machine)
@@ -108,23 +92,51 @@ def get_ip_address(machine, resolving_machine)
  end
  end
  ip || (machine.ssh_info ? machine.ssh_info[:host] : nil)
- end 
+ end
  end
 
  def get_machines
  if @global_env.config_global.hostmanager.include_offline?
- machines = []
- @global_env.machine_names.each do |name|
- begin
- @global_env.machine(name, @provider)
- machines << [name, @provider]
- rescue Vagrant::Errors::MachineNotFound
+ machines = @global_env.machine_names
+ else
+ machines = @global_env.active_machines
+ end
+ # Collect only machines that exist for the current provider
+ machines.collect do |name, _|
+ begin
+ machine = @global_env.machine(name, @provider)
+ rescue Vagrant::Errors::MachineNotFound
+ # ignore
+ end
+ machine
  end
- end
- machines
+ .reject(&:nil?)
+ end
+
+ def get_new_content(header, footer, body, old_content)
+ if body.empty?
+ block = "\n"
+ else
+ block = "\n\n" + header + body + footer + "\n"
+ end
+ # Pattern for finding existing block
+ header_pattern = Regexp.quote(header)
+ footer_pattern = Regexp.quote(footer)
+ pattern = Regexp.new("\n*#{header_pattern}.*?#{footer_pattern}\n*", Regexp::MULTILINE)
+ # Replace existing block or append
+ old_content.match(pattern) ? old_content.sub(pattern, block) : old_content.rstrip + block
+ end
+
+ def read_or_create_id
+ file = Pathname.new("#{@global_env.local_data_path}/hostmanager/id")
+ if (file.file?)
+ id = file.read.strip
  else
- @global_env.active_machines
+ id = SecureRandom.uuid
+ file.dirname.mkpath
+ file.open('w') { |io| io.write(id) }
  end
+ id
  end
 
  ## Windows support for copying files, requesting elevated privileges if necessary