NAME

       VM::EC2::Instance::State::Change - Represent an EC2 instance's change in state.

SYNOPSIS

            # find all stopped instances
           @instances = $ec2->describe_instances(-filter=>{'instance-state-name'=>'stopped'});

           # start them
           @state_change = $ec2->start_instances(@instances)

           foreach my $sc (@state_change) {
               my $instanceId    = $sc->instanceId;
               my $currentState  = $sc->currentState;
               my $previousState = $sc->previousState;
           }

           # poll till the first instance is running
           sleep 2 until $state_change[0]->current_status eq 'running';

DESCRIPTION

       This object represents a state change in an Amazon EC2 instance.  It is returned by
       VM::EC2 start_instances(), stop_instances(), terminate_instances(), reboot_instances() and
       the corresponding VM::EC2::Instance methods. In addition, this object is returned by calls
       to VM::EC2::Instance->instanceState().

METHODS

       These object methods are supported:

        instanceId      -- The instanceId.
        currentState    -- The instanceId's current state AT THE TIME
                            THE STATECHANGE OBJECT WAS CREATED. One of
                            "terminated", "running", "stopped", "stopping",
                            "shutting-down".
        previousState   -- The instanceID's previous state AT THE TIME
                            THE STATECHANGE OBJECT WAS CREATED.

       Note that currentState and previousState return a VM::EC2::Instance::State object, which
       provides both string-readable forms and numeric codes representing the state.

       In addition, the method provides the following convenience method:

   $state = $state_change->current_status()
       This method returns the current state of the instance. This is the correct method to call
       if you are interested in knowing what the instance is doing right now.

   STRING OVERLOADING
       In a string context, the method will return the string representation of currentState.

SEE ALSO

       VM::EC2 VM::EC2::Generic VM::EC2::State VM::EC2::Instance

AUTHOR

       Lincoln Stein <lincoln.stein@gmail.com>.

       Copyright (c) 2011 Ontario Institute for Cancer Research

       This package and its accompanying libraries is free software; you can redistribute it
       and/or modify it under the terms of the GPL (either version 1, or at your option, any
       later version) or the Artistic License 2.0.  Refer to LICENSE for the full license text.
       In addition, please see DISCLAIMER.txt for disclaimers of warranty.