Class: DeviceAPI::Execution

Inherits:
Object
  • Object
show all
Defined in:
lib/device_api/execution.rb

Overview

Provides method to execute terminal commands in a reusable way

Constant Summary collapse

COMMAND_TIMEOUT =

execute_with_timeout_and_retry constants

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COMMAND_RETRIES =

base number of seconds to wait until adb command times out

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Class Method Summary collapse

Class Method Details

.execute(command) ⇒ Object

Execute out to shell Returns a struct collecting the execution results struct = DeviceAPI::ADB.execute( ‘adb devices’ ) struct.stdout #=> “std out” struct.stderr #=> ” strict.exit #=> 0



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# File 'lib/device_api/execution.rb', line 25

def self.execute(command)
  result = OpenStruct.new

  stdout, stderr, status = Open3.capture3(command)

  result.exit = status.exitstatus
  result.stdout = stdout
  result.stderr = stderr

  result
end

.execute_with_timeout_and_retry(command) ⇒ Object

Execute a command with retries if the command fails to return



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# File 'lib/device_api/execution.rb', line 38

def self.execute_with_timeout_and_retry(command)
  retries_left = COMMAND_RETRIES
  cmd_successful = false
  result = 0

  while (retries_left > 0) and (cmd_successful == false) do
    begin
      ::Timeout.timeout(COMMAND_TIMEOUT) do
        result = execute(command)
        cmd_successful = true
      end
    rescue ::Timeout::Error
      retries_left -= 1
      if retries_left > 0
        DeviceAPI.log.error "Command #{command} timed out after #{COMMAND_TIMEOUT.to_s} sec, retrying,"\
            + " #{retries_left.to_s} attempts left.."
      end
    end
  end

  if retries_left < COMMAND_RETRIES # if we had to retry
    if cmd_successful == false
      msg = "Command #{command} timed out after #{COMMAND_RETRIES.to_s} retries. !"\
        + " Exiting.."
      DeviceAPI.log.fatal(msg)
      raise DeviceAPI::CommandTimeoutError.new(msg)
    else
      DeviceAPI.log.info "Command #{command} succeeded execution after retrying"
    end
  end

  result
end