Module: BlackStack::Infrastructure::NodeModule

Included in:
Node
Defined in:
lib/blackstack-nodes.rb

Overview

this module has attributes an methods used by both classes Node and Node.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#logger ⇒ Object

non-database attributes, used for ssh connection and logging



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# File 'lib/blackstack-nodes.rb', line 13

def logger
  @logger
end

#name ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def name
  @name
end

#net_remote_ip ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def net_remote_ip
  @net_remote_ip
end

#ssh ⇒ Object

non-database attributes, used for ssh connection and logging



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# File 'lib/blackstack-nodes.rb', line 13

def ssh
  @ssh
end

#ssh_password ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def ssh_password
  @ssh_password
end

#ssh_port ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def ssh_port
  @ssh_port
end

#ssh_private_key_file ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def ssh_private_key_file
  @ssh_private_key_file
end

#ssh_username ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def ssh_username
  @ssh_username
end

#tags ⇒ Object

:name is this is just a descriptive name for the node. It is not the host name, nor the domain, nor any ip.



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# File 'lib/blackstack-nodes.rb', line 11

def tags
  @tags
end

Class Method Details

.descriptor_errors(h) ⇒ Object 



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# File 'lib/blackstack-nodes.rb', line 15

def self.descriptor_errors(h)
  errors = []

  # validate: the parameter h is a hash
  errors << "The parameter h is not a hash" unless h.is_a?(Hash)

  # validate: the parameter h has a key :name
  errors << "The parameter h does not have a key :name" unless h.has_key?(:name)

  # validate: the parameter h[:name] is a string
  errors << "The parameter h[:name] is not a string" unless h[:name].is_a?(String)

  # validate: the paramerer h has a key :net_remote_ip
  errors << "The parameter h does not have a key :net_remote_ip" unless h.has_key?(:net_remote_ip)

  # validate: the paramerer h has a key :ssh_username
  errors << "The parameter h does not have a key :ssh_username" unless h.has_key?(:ssh_username)

  # validate: the parameter h[:ssh_username] is a string
  errors << "The parameter h[:ssh_username] is not a string" unless h[:ssh_username].is_a?(String)

  # if the parameter h has a key :ssh_private_key_file
  if h.has_key?(:ssh_private_key_file) && !h[:ssh_private_key_file].nil?
    # validate: the parameter h[:ssh_private_key_file] is a string
    errors << "The parameter h[:ssh_private_key_file] is not a string" unless h[:ssh_private_key_file].is_a?(String)

    # validate: the parameter h[:ssh_private_key_file] is a string
    errors << "The parameter h[:ssh_private_key_file] is not a string" unless h[:ssh_private_key_file].is_a?(String)
  else
    # validate: the parameter h has a key :ssh_password
    errors << "The parameter h does not have a key :ssh_password nor :ssh_private_key_file" unless h.has_key?(:ssh_password)

    # validate: the parameter h[:ssh_password] is a string
    errors << "The parameter h[:ssh_password] is not a string" unless h[:ssh_password].is_a?(String)
  end

  # if the parameter h has a key :tags
  if h.has_key?(:tags) && !h[:tags].nil?
    # validate: the parameter h[:tags] is an array or a string
    errors << "The parameter h[:tags] is not an array or a string" unless h[:tags].is_a?(Array) || h[:tags].is_a?(String)
  end

  # return
  errors
end

Instance Method Details

#connect ⇒ Object 



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# File 'lib/blackstack-nodes.rb', line 104

def connect
  # connect
  if self.using_password?
    self.ssh = Net::SSH.start(self.net_remote_ip, self.ssh_username, :password => self.ssh_password, :port => self.ssh_port)
  elsif self.using_private_key_file?
    self.ssh = Net::SSH.start(self.net_remote_ip, self.ssh_username, :keys => self.ssh_private_key_file, :port => self.ssh_port)
  else
    raise "No ssh credentials available"
  end
  self.ssh
end

#disconnect ⇒ Object

def connect



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# File 'lib/blackstack-nodes.rb', line 116

def disconnect
  self.ssh.close
end

#exec(command, output_file: "$HOME/.bash-command-stdout-buffer", error_file: "$HOME/.bash-command-stderr-buffer", exit_code_file: "$HOME/.bash-command-exit-code") ⇒ Object

Execute a command on the remote server and return the output. If the exit code of the command is not zero, an exception is raised, with the messages pushed into the stderr. If the exit code of the command is zero, the messages pushed into the stdout are returned.

IMPORTANT: Messages pushed into stderr re not always error. Reference:



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# File 'lib/blackstack-nodes.rb', line 129

def exec(
  command, 
  output_file: "$HOME/.bash-command-stdout-buffer", 
  error_file: "$HOME/.bash-command-stderr-buffer",
  exit_code_file: "$HOME/.bash-command-exit-code"
)
  # Construct the remote command with redirection for stdout, stderr, and capturing exit code
  remote_command = "#{command} > #{output_file} 2> #{error_file}; echo $? > #{exit_code_file}"

  # Execute the command on the remote server, truncating output, error, and exit code files
  self.ssh.exec!("truncate -s 0 #{output_file} #{error_file} #{exit_code_file}")

  # Execute the command on the remote server, truncating output, error, and exit code files
  self.ssh.exec!(remote_command)

  # Retrieve the exit code
  exit_code = self.ssh.exec!("cat #{exit_code_file}").to_s.chomp.to_i

  # Retrieve the content of the error file from the remote server
  error_content = self.ssh.exec!("cat #{error_file}").to_s.chomp

  # Check if the exit code is not zero
  if exit_code != 0
    # Raise an exception with the error message
    raise "Command failed with exit code #{exit_code}:\n#{error_content}"
  end

  # Retrieve and return the content of the output file from the remote server
  # Truncate any trailing newline character
  self.ssh.exec!("cat #{output_file}").to_s.chomp
end

#initialize(h, i_logger = nil) ⇒ Object

def self.descriptor_errors(h)



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# File 'lib/blackstack-nodes.rb', line 61

def initialize(h, i_logger=nil)
  errors = BlackStack::Infrastructure::NodeModule.descriptor_errors(h)
  # raise an exception if any error happneed
  raise "The node descriptor is not valid: #{errors.uniq.join(".\n")}" if errors.length > 0
  # map attributes
  self.name = h[:name]
  self.net_remote_ip = h[:net_remote_ip]
  self.ssh_username = h[:ssh_username]
  self.ssh_password = h[:ssh_password] 
  self.ssh_port = h[:ssh_port]
  self.ssh_private_key_file = h[:ssh_private_key_file]
  # parse the tags
  if h.has_key?(:tags) && !h[:tags].nil?
    self.tags = h[:tags].is_a?(Array) ? h[:tags] : [h[:tags]]
  else
    self.tags = []
  end
  # create a logger
  self.logger = !i_logger.nil? ? i_logger : BlackStack::DummyLogger.new(nil)
end

#reboot ⇒ Object

def exec



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# File 'lib/blackstack-nodes.rb', line 161

def reboot()
  tries = 0
  max_tries = 20
  success = false

  host = self

  logger.logs 'reboot... '
  #stdout = host.reboot
  begin
    stdout = self.exec("reboot")
  rescue
  end
  logger.done #logf("done (#{stdout})")

  while tries < max_tries && !success
      begin
          tries += 1

          delay = 10
          logger.logs "wait #{delay.to_s} seconds... "
          sleep(delay)
          logger.done

          logger.logs "connecting (try #{tries.to_s})... "
          host.connect
          logger.done

          success = true
      rescue => e
          logger.logf e.to_s #error e
      end
  end # while 
  raise 'reboot failed' if !success
end

#tail(filename, n = 10) ⇒ Object

return the latest n` lines of the file specified by the filename parameter



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# File 'lib/blackstack-nodes.rb', line 250

def tail(filename, n=10)
  self.ssh.exec!("tail -n #{n.to_s} #{filename}")
end

#to_hash ⇒ Object

def self.create(h)



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# File 'lib/blackstack-nodes.rb', line 82

def to_hash
  {
    :name => self.name,
    :net_remote_ip => self.net_remote_ip,
    :ssh_username => self.ssh_username,
    :ssh_password => self.ssh_password, 
    :ssh_port => self.ssh_port,
    :ssh_private_key_file => self.ssh_private_key_file,
    :tags => self.tags
  }
end

#usage ⇒ Object

Return a hash descriptor of the status of the node



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# File 'lib/blackstack-nodes.rb', line 198

def usage()
  ret = {}

  #self.connect

  ret[:b_total_memory] = self.ssh.exec!('cat /proc/meminfo | grep MemTotal').delete('^0-9').to_i*1024
  ret[:kb_total_memory] = ret[:b_total_memory] / 1024
  ret[:mb_total_memory] = ret[:kb_total_memory] / 1024
  ret[:gb_total_memory] = ret[:mb_total_memory] / 1024

  ret[:kb_free_memory] = self.ssh.exec!('cat /proc/meminfo | grep MemFree').delete('^0-9').to_i
  ret[:mb_free_memory] = ret[:kb_free_memory] / 1024
  ret[:gb_free_memory] = ret[:mb_free_memory] / 1024

  # run bash commend to get the total disk space
  ret[:mb_total_disk] = self.ssh.exec!('df -m / | tail -1 | awk \'{print $2}\'').to_i
  ret[:gb_total_disk] = ret[:mb_total_disk] / 1024
  # run bash command to get the free disk space
  ret[:mb_free_disk] = self.ssh.exec!('df -m / | tail -1 | awk \'{print $4}\'').to_i
  ret[:gb_free_disk] = ret[:mb_free_disk] / 1024
  
  # run bash command to get hostname
  ret[:hostname] = self.ssh.exec!('hostname').strip!

  # run bash command to get the CPU load
  # reference: https://stackoverflow.com/questions/9229333/how-to-get-overall-cpu-usage-e-g-57-on-linux
  ret[:cpu_load_average] = self.ssh.exec!("awk '{u=$2+$4; t=$2+$4+$5; if (NR==1){u1=u; t1=t;} else print ($2+$4-u1) * 100 / (t-t1) \"%\"; }' <(grep 'cpu ' /proc/stat) <(sleep 1;grep 'cpu ' /proc/stat)").to_s

  # TODO: monitor the overall Network I/O load

  # TODO: monitor the overall Disk I/O load

  # mapping cpu status
  ret[:cpu_architecture] = self.ssh.exec!('lscpu | grep Architecture').split(':')[1].strip!
  ret[:cpu_speed] = self.ssh.exec!('lscpu | grep "CPU MHz:"').split(':')[1].strip!.to_f.round
  #ret[:cpu_model] = self.ssh.exec!('lscpu | grep "Model"').split(':')[1].strip!
  #ret[:cpu_type] = ret[:cpu_model].split(' ')[0]
  ret[:cpu_number] = self.ssh.exec!('lscpu | grep "^CPU(s):"').split(':')[1].strip!.to_i

  # mapping disk status
  #self.disk_total = mb_total_disk.to_i
  #self.disk_free = mb_free_disk.to_i

  # mapping lan attributes
  ret[:net_mac_address] = self.ssh.exec!('ifconfig | grep ether').split[1].upcase.strip.gsub(':', '-') 

  #self.disconnect

  ret
end

#using_password? ⇒ Boolean

return true if the node is all set to connect using ssh user and password.

Returns:

  • (Boolean) 


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# File 'lib/blackstack-nodes.rb', line 95

def using_password?
  !self.net_remote_ip.nil? && !self.ssh_username.nil? && !self.ssh_password.nil?
end

#using_private_key_file? ⇒ Boolean

return true if the node is all set to connect using a private key file.

Returns:

  • (Boolean) 


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# File 'lib/blackstack-nodes.rb', line 100

def using_private_key_file?
  !self.net_remote_ip.nil? && !self.ssh_username.nil? && !self.ssh_private_key_file.nil?
end