Class: Merb::Server

Inherits:
Object show all
Defined in:
lib/merb-core/server.rb

Overview

Server encapsulates the management of Merb daemons.

Class Method Summary collapse

Class Method Details

._change_privilege(user, group = user) ⇒ Object

Change privileges of the process to the specified user and group.

Parameters

user<String>

The user who should own the server process.

group<String>

The group who should own the server process.

Alternatives

If group is left out, the user will be used as the group.



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# File 'lib/merb-core/server.rb', line 233

def _change_privilege(user, group=user)

  puts "Changing privileges to #{user}:#{group}"

  uid, gid = Process.euid, Process.egid
  target_uid = Etc.getpwnam(user).uid
  target_gid = Etc.getgrnam(group).gid

  if uid != target_uid || gid != target_gid
    # Change process ownership
    Process.initgroups(user, target_gid)
    Process::GID.change_privilege(target_gid)
    Process::UID.change_privilege(target_uid)
  end
rescue Errno::EPERM => e
  puts "Couldn't change user and group to #{user}:#{group}: #{e}"
end

.alive?(port) ⇒ Boolean

Parameters

port<~to_s>

The port to check for Merb instances on.

Returns

Boolean

True if Merb is running on the specified port.

Returns:

  • (Boolean) 


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# File 'lib/merb-core/server.rb', line 63

def alive?(port)
  puts "About to check if port #{port} is alive..." if Merb::Config[:verbose]
  pidfile = pid_file(port)
  puts "Pidfile is #{pidfile}..." if Merb::Config[:verbose]
  pid = IO.read(pidfile).chomp.to_i
  puts "Process id is #{pid}" if Merb::Config[:verbose]
  Process.kill(0, pid)
  true
rescue
  false
end

.change_privilege ⇒ Object 



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# File 'lib/merb-core/server.rb', line 130

def change_privilege
  if Merb::Config[:user]
    if Merb::Config[:group]
      puts "About to change privilege to group #{Merb::Config[:group]} and user #{Merb::Config[:user]}" if Merb::Config[:verbose]
      _change_privilege(Merb::Config[:user], Merb::Config[:group])
    else
      puts "About to change privilege to user #{Merb::Config[:user]}" if Merb::Config[:verbose]
      _change_privilege(Merb::Config[:user])
    end
  end
end

.daemonize(port) ⇒ Object

Parameters

port<~to_s>

The port of the Merb process to daemonize.



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# File 'lib/merb-core/server.rb', line 112

def daemonize(port)
  puts "About to fork..." if Merb::Config[:verbose]
  fork do
    Process.setsid
    exit if fork
    File.umask 0000
    STDIN.reopen "/dev/null"
    STDOUT.reopen "/dev/null", "a"
    STDERR.reopen STDOUT
    trap("TERM") { exit }
    Dir.chdir Merb::Config[:merb_root]
    at_exit { remove_pid_file(port) }
    Merb::Config[:port] = port
    BootLoader.run
    Merb.adapter.start(Merb::Config.to_hash)
  end
end

.kill(port, sig = 9) ⇒ Object

Parameters

port<~to_s>

The port of the Merb process to kill.

sig<~to_s>

The signal to send to the process. Defaults to 9.

Alternatives

If you pass “all” as the port, the signal will be sent to all Merb processes.



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# File 'lib/merb-core/server.rb', line 82

def kill(port, sig=9)
  Merb::BootLoader::BuildFramework.run
  begin
    pidfiles = port == "all" ?
      pid_files : [ pid_file(port) ]

    pidfiles.each do |f|
      pid = IO.read(f).chomp.to_i
      begin
        Process.kill(sig, pid)
        FileUtils.rm(f) if File.exist?(f)
        puts "killed PID #{pid} with signal #{sig}"
      rescue Errno::EINVAL
        puts "Failed to kill PID #{pid}: '#{sig}' is an invalid or unsupported signal number."
      rescue Errno::EPERM
        puts "Failed to kill PID #{pid}: Insufficient permissions."
      rescue Errno::ESRCH
        puts "Failed to kill PID #{pid}: Process is deceased or zombie."
        FileUtils.rm f
      rescue Exception => e
        puts "Failed to kill PID #{pid}: #{e.message}"
      end
    end
  ensure
    exit
  end
end

.pid_file(port) ⇒ Object

Gets the pid file for the specified port.

Parameters

port<~to_s>

The port of the Merb process to whom the the PID file belongs to.

Returns

String

Location of pid file for specified port. If clustered and pid_file option is specified, it adds the port value to the path.



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# File 'lib/merb-core/server.rb', line 188

def pid_file(port)
  if Merb::Config[:pid_file]
    pidfile = Merb::Config[:pid_file]
    if Merb::Config[:cluster]
      ext = File.extname(Merb::Config[:pid_file])
      base = File.basename(Merb::Config[:pid_file], ext)
      dir = File.dirname(Merb::Config[:pid_file])
      File.join(dir, "#{base}.#{port}#{ext}")
    else
      Merb::Config[:pid_file]
    end
  else
    pidfile = Merb.log_path / "merb.#{port}.pid"
    Merb.log_path / "merb.#{port}.pid"
  end
end

.pid_files ⇒ Object

Get a list of the pid files.

Returns

Array

List of pid file paths. If not clustered, array contains a single path.



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# File 'lib/merb-core/server.rb', line 210

def pid_files
 if Merb::Config[:pid_file]
   if Merb::Config[:cluster]
     ext = File.extname(Merb::Config[:pid_file])
     base = File.basename(Merb::Config[:pid_file], ext)
     dir = File.dirname(Merb::Config[:pid_file])
     Dir[dir / "#{base}.*#{ext}"]
   else
     [ Merb::Config[:pid_file] ]
   end
 else
   Dir[Merb.log_path / "merb.*.pid"]
 end
end

.remove_pid_file(port) ⇒ Object

Removes a PID file used by the server from the filesystem. This uses :pid_file options from configuration when provided or merb.<port>.pid in log directory by default.

Parameters

port<~to_s>

The port of the Merb process to whom the the PID file belongs to.

Alternatives

If Merb::Config has been specified, that will be used instead of the port based PID file.



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# File 'lib/merb-core/server.rb', line 153

def remove_pid_file(port)
  pidfile = pid_file(port)
  puts "Removing pid file #{pidfile} (port is #{port})..."
  FileUtils.rm(pidfile) if File.exist?(pidfile)
end

.start(port, cluster = nil) ⇒ Object

Start a Merb server, in either foreground, daemonized or cluster mode.

Parameters

port<~to_i>

The port to which the first server instance should bind to. Subsequent server instances bind to the immediately following ports.

cluster<~to_i>

Number of servers to run in a cluster.

Alternatives

If cluster is left out, then one process will be started. This process will be daemonized if Merb::Config is true.



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# File 'lib/merb-core/server.rb', line 20

def start(port, cluster=nil)
  @port = port
  @cluster = cluster
  if @cluster
    @port.to_i.upto(@port.to_i + @cluster.to_i-1) do |port|
      pidfile = pid_file(port)
      pid = IO.read(pidfile).chomp.to_i if File.exist?(pidfile)

      unless alive?(port)
        remove_pid_file(port)
        puts "Starting merb server on port #{port}, pid file: #{pidfile} and process id is #{pid}" if Merb::Config[:verbose]
        daemonize(port)
      else
        raise "Merb is already running: port is #{port}, pid file: #{pidfile}, process id is #{pid}"
      end
    end
  elsif Merb::Config[:daemonize]
    pidfile = pid_file(port)
    pid = IO.read(pidfile).chomp.to_i if File.exist?(pidfile)

    unless alive?(@port)
      remove_pid_file(@port)
      puts "Daemonizing..." if Merb::Config[:verbose]
      daemonize(@port)
    else
      raise "Merb is already running: port is #{port}, pid file: #{pidfile}, process id is #{pid}"
    end
  else
    trap('TERM') { exit }
    trap('INT') { puts "\nExiting"; exit }
    puts "Running bootloaders..." if Merb::Config[:verbose]
    BootLoader.run
    puts "Starting Rack adapter..." if Merb::Config[:verbose]
    Merb.adapter.start(Merb::Config.to_hash)
  end
end

.store_pid(port) ⇒ Object

Stores a PID file on the filesystem. This uses :pid_file options from configuration when provided or merb.<port>.pid in log directory by default.

Parameters

port<~to_s>

The port of the Merb process to whom the the PID file belongs to.

Alternatives

If Merb::Config has been specified, that will be used instead of the port based PID file.



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# File 'lib/merb-core/server.rb', line 170

def store_pid(port)
  pidfile = pid_file(port)
  puts "Storing pid file to #{pidfile}..."
  FileUtils.mkdir_p(File.dirname(pidfile)) unless File.directory?(File.dirname(pidfile))
  puts "Created directory, writing process id..." if Merb::Config[:verbose]
  File.open(pidfile, 'w'){ |f| f.write("#{Process.pid}") }
end