class InfrastructureManager:
"""
InfrastructureManager class is the main entry point to the AppScale
Infrastructure Manager implementation. An instance of this class can
be used to start new virtual machines in a specified cloud environment
and terminate virtual machines when they are no longer required. Instances
of this class also keep track of the virtual machines spawned by them
and hence each InfrastructureManager instance can be queried to obtain
information about any virtual machines spawned by each of them in the
past.
This implementation is completely cloud infrastructure agnostic
and hence can be used to spawn/terminate instances on a wide range of
cloud (IaaS) environments. All the cloud environment specific operations
are delegated to a separate cloud agent and the InfrastructureManager
initializes cloud agents on demand by looking at the 'infrastructure'
parameter passed into the methods of this class.
"""
# Default reasons which might be returned by this module
REASON_BAD_SECRET = 'bad secret'
REASON_BAD_VM_COUNT = 'bad vm count'
REASON_BAD_ARGUMENTS = 'bad arguments'
REASON_OPERATION_ID_NOT_FOUND = 'operation_id not found'
REASON_NONE = 'none'
# Parameters required by InfrastructureManager
PARAM_OPERATION_ID = 'operation_id'
PARAM_INFRASTRUCTURE = 'infrastructure'
PARAM_NUM_VMS = 'num_vms'
# States a particular request could be in.
STATE_PENDING = 'pending'
STATE_SUCCESS = 'success'
STATE_FAILED = 'failed'
# A list of parameters required to query the InfrastructureManager about
# the state of a run_instances request.
DESCRIBE_INSTANCES_REQUIRED_PARAMS = (PARAM_OPERATION_ID,)
# A list of parameters required to initiate a VM deployment process
RUN_INSTANCES_REQUIRED_PARAMS = (
PARAM_INFRASTRUCTURE,
PARAM_NUM_VMS
)
# A list of parameters required to initiate a VM termination process
TERMINATE_INSTANCES_REQUIRED_PARAMS = ( PARAM_INFRASTRUCTURE, )
def __init__(self, params=None, blocking=False):
"""
Create a new InfrastructureManager instance. This constructor
accepts an optional boolean parameter which decides whether the
InfrastructureManager instance should operate in blocking mode
or not. A blocking InfrastructureManager does not return until
each requested run/terminate operation is complete. This mode
is useful for testing and verification purposes. In a real-world
deployment it's advisable to instantiate the InfrastructureManager
in the non-blocking mode as run/terminate operations could take
a rather long time to complete. By default InfrastructureManager
instances are created in the non-blocking mode.
Args
params A dictionary of parameters. Optional parameter. If
specified it must at least include the 'store_type' parameter.
blocking Whether to operate in blocking mode or not. Optional
and defaults to false.
"""
self.blocking = blocking
self.secret = utils.get_secret()
self.agent_factory = InfrastructureAgentFactory()
if params is not None:
store_factory = PersistentStoreFactory()
store = store_factory.create_store(params)
self.operation_ids = PersistentDictionary(store)
else:
self.operation_ids = PersistentDictionary()
def describe_operation(self, parameters, secret):
"""
Query the InfrastructureManager instance for details regarding
an operation id for running or terminating instances. This method accepts
a dictionary of parameters and a secret for authentication purposes.
The dictionary of parameters must include an 'operation_id' parameter
which is used to lookup calls that have been made to run or terminate
instances.
Args:
parameters A dictionary of parameters which contains a valid
'operation_id' parameter. A valid 'operation_id'
is an ID issued by the run_instances method of the
same InfrastructureManager object. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
invalid key or an invalid 'operation_id':
'success': False
'reason': is set to an error message describing the cause.
If the provided secret key is valid and the parameters map contains
a valid 'operation_id' parameter, this method will return a
dictionary containing the following keys for the specified cases.
For a run_instances operation_id:
'success': True or False depending on the outcome of the virtual
machine deployment process.
'state': pending, failed, or success
'reason': set only in a failed case.
'vm_info': a dictionary containing the IP addresses of the spawned
virtual machines or None if the virtual machine deployment had
failed or still in the 'pending' state.
For a terminate_instances operation_id:
'success': True or False depending on the outcome of the virtual
machine deployment process.
'state': pending, failed, or success
'reason': set only in a failed case.
* note that this dictionary does not contain 'vm_info'.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.DESCRIBE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
operation_id = parameters[self.PARAM_OPERATION_ID]
if self.operation_ids.has_key(operation_id):
return self.operation_ids.get(operation_id)
else:
return self.__generate_response(False, self.REASON_OPERATION_ID_NOT_FOUND)
def run_instances(self, parameters, secret):
"""
Start a new virtual machine deployment using the provided parameters. The
input parameter set must include an 'infrastructure' parameter which indicates
the exact cloud environment to use. Value of this parameter will be used to
instantiate a cloud environment specific agent which knows how to interact
with the specified cloud platform. The parameters map must also contain a
'num_vms' parameter which indicates the number of virtual machines that should
be spawned. In addition to that any parameters required to spawn VMs in the
specified cloud environment must be included in the parameters map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method will simply kick off the VM deployment process and return
immediately.
Args:
parameters A parameter map containing the keys 'infrastructure',
'num_vms' and any other cloud platform specific
parameters. Alternatively one may provide a valid
JSON string instead of a dictionary object.
secret A previously established secret
Returns:
If the secret is valid and all the required parameters are available in
the input parameter map, this method will return a dictionary containing
a special 'operation_id' key. If the secret is invalid or a required
parameter is missing, this method will return a different map with the
key 'success' set to False and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
utils.log('Received a request to run instances.')
if self.secret != secret:
utils.log('Incoming secret {0} does not match the current secret {1} - '\
'Rejecting request.'.format(secret, self.secret))
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.RUN_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
num_vms = int(parameters[self.PARAM_NUM_VMS])
if num_vms <= 0:
utils.log('Invalid VM count: {0}'.format(num_vms))
return self.__generate_response(False, self.REASON_BAD_VM_COUNT)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters, BaseAgent.OPERATION_RUN)
except AgentConfigurationException as exception:
return self.__generate_response(False, str(exception))
operation_id = utils.get_random_alphanumeric()
status_info = {
'success': True,
'reason': 'received run request',
'state': self.STATE_PENDING,
'vm_info': None
}
self.operation_ids.put(operation_id, status_info)
utils.log('Generated operation id {0} for this run '
'instances request.'.format(operation_id))
if self.blocking:
self.__spawn_vms(agent, num_vms, parameters, operation_id)
else:
thread.start_new_thread(self.__spawn_vms,
(agent, num_vms, parameters, operation_id))
utils.log('Successfully started run instances request {0}.'.format(
operation_id))
return self.__generate_response(True,
self.REASON_NONE, {'operation_id': operation_id})
def terminate_instances(self, parameters, secret):
"""
Terminate a virtual machine using the provided parameters.
The input parameter map must contain an 'infrastructure' parameter which
will be used to instantiate a suitable cloud agent. Any additional
environment specific parameters should also be available in the same
map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method simply starts the VM termination process and returns immediately.
Args:
parameters A dictionary of parameters containing the required
'infrastructure' parameter and any other platform
dependent required parameters. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
If the secret is valid and all the required parameters are available in
the input parameter map, this method will return a dictionary containing
a special 'operation_id' key. If the secret is invalid or a required
parameter is missing, this method will return a different map with the
key 'success' set to False and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.TERMINATE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters,
BaseAgent.OPERATION_TERMINATE)
except AgentConfigurationException as exception:
return self.__generate_response(False, str(exception))
operation_id = utils.get_random_alphanumeric()
status_info = {
'success': True,
'reason': 'received kill request',
'state': self.STATE_PENDING
}
self.operation_ids.put(operation_id, status_info)
utils.log('Generated operation id {0} for this terminate instances '
'request.'.format(operation_id))
if self.blocking:
self.__kill_vms(agent, parameters, operation_id)
else:
thread.start_new_thread(self.__kill_vms,
(agent, parameters, operation_id))
utils.log('Successfully started terminate instances request {0}.'.format(
operation_id))
return self.__generate_response(True,
self.REASON_NONE, {'operation_id': operation_id})
def attach_disk(self, parameters, disk_name, instance_id, secret):
""" Contacts the infrastructure named in 'parameters' and tells it to
attach a persistent disk to this machine.
Args:
parameters: A dict containing the credentials necessary to send requests
to the underlying cloud infrastructure.
disk_name: A str corresponding to the name of the persistent disk that
should be attached to this machine.
instance_id: A str naming the instance id that the disk should be attached
to (typically this machine).
secret: A str that authenticates the caller.
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
disk_location = agent.attach_disk(parameters, disk_name, instance_id)
return self.__generate_response(True, self.REASON_NONE,
{'location' : disk_location})
@classmethod
def __describe_vms(self, agent, parameters):
"""
Private method for calling the agent to describe VMs.
Args:
agent Infrastructure agent in charge of current operation
parameters A dictionary of parameters
Returns:
If the agent is able to describe instances, return the list of instance
ids, public ips, and private ips. If the agent fails, return empty lists.
"""
try:
return agent.describe_instances(parameters)
except (AgentConfigurationException, AgentRuntimeException) as exception:
utils.log('Agent call to describe instances failed with {0}'.format(
str(exception)))
return [], [], []
def __spawn_vms(self, agent, num_vms, parameters, operation_id):
"""
Private method for starting a set of VMs
Args:
agent Infrastructure agent in charge of current operation
num_vms No. of VMs to be spawned
parameters A dictionary of parameters
operation_id Operation ID of the current run request
"""
status_info = self.operation_ids.get(operation_id)
active_public_ips, active_private_ips, active_instances = \
self.__describe_vms(agent, parameters)
try:
security_configured = agent.configure_instance_security(parameters)
instance_info = agent.run_instances(num_vms, parameters,
security_configured, public_ip_needed=False)
ids = instance_info[0]
public_ips = instance_info[1]
private_ips = instance_info[2]
status_info['state'] = self.STATE_SUCCESS
status_info['vm_info'] = {
'public_ips': public_ips,
'private_ips': private_ips,
'instance_ids': ids
}
utils.log('Successfully finished run instances request {0}.'.format(
operation_id))
except (AgentConfigurationException, AgentRuntimeException) as exception:
# Check if we have had partial success starting instances.
public_ips, private_ips, instance_ids = \
self.__describe_vms(agent, parameters)
public_ips = agent.diff(public_ips, active_public_ips)
if public_ips:
private_ips = agent.diff(private_ips, active_private_ips)
instance_ids = agent.diff(instance_ids, active_instances)
status_info['state'] = self.STATE_SUCCESS
status_info['vm_info'] = {
'public_ips': public_ips,
'private_ips': private_ips,
'instance_ids': instance_ids
}
else:
status_info['state'] = self.STATE_FAILED
# Mark it as failed either way since the AppController never checks
# 'success' and it technically failed.
status_info['success'] = False
status_info['reason'] = str(exception)
utils.log('Updating run instances request with operation id {0} to '
'failed status because: {1}'\
.format(operation_id, str(exception)))
self.operation_ids.put(operation_id, status_info)
def __kill_vms(self, agent, parameters, operation_id):
"""
Private method for stopping a VM. This method assumes it has only been
told to stop one VM.
Args:
agent Infrastructure agent in charge of current operation
parameters A dictionary of parameters
operation_id Operation ID of the current run request
"""
status_info = self.operation_ids.get(operation_id)
try:
agent.terminate_instances(parameters)
status_info['state'] = self.STATE_SUCCESS
except AgentRuntimeException as exception:
status_info['state'] = self.STATE_FAILED
status_info['reason'] = str(exception)
utils.log('Updating terminate instances request with operation id {0} '
'to failed status because: {1}'\
.format(operation_id, str(exception)))
self.operation_ids.put(operation_id, status_info)
def __generate_response(self, status, msg, extra=None):
"""
Generate an infrastructure manager service response
Args:
status A boolean value indicating the status
msg A reason message (useful if this a failed operation)
extra Any extra fields to be included in the response (Optional)
Returns:
A dictionary containing the operation response
"""
utils.log("Sending success = {0}, reason = {1}".format(status, msg))
response = {'success': status, 'reason': msg}
if extra is not None:
for key, value in extra.items():
response[key] = value
return response
def __validate_args(self, parameters, secret):
"""
Validate the arguments provided by user.
Args:
parameters A dictionary (or a JSON string) provided by the client
secret Secret sent by the client
Returns:
Processed user arguments
Raises
TypeError If at least one user argument is not of the current type
"""
if type(parameters) != type('') and type(parameters) != type({}):
raise TypeError('Invalid data type for parameters. Must be a '
'JSON string or a dictionary.')
elif type(secret) != type(''):
raise TypeError('Invalid data type for secret. Must be a string.')
if type(parameters) == type(''):
parameters = json.loads(parameters)
return parameters, secret
class InfrastructureManager:
"""
InfrastructureManager class is the main entry point to the AppScale
Infrastructure Manager implementation. An instance of this class can
be used to start new virtual machines in a specified cloud environment
and terminate virtual machines when they are no longer required. Instances
of this class also keep track of the virtual machines spawned by them
and hence each InfrastructureManager instance can be queried to obtain
information about any virtual machines spawned by each of them in the
past.
This implementation is completely cloud infrastructure agnostic
and hence can be used to spawn/terminate instances on a wide range of
cloud (IaaS) environments. All the cloud environment specific operations
are delegated to a separate cloud agent and the InfrastructureManager
initializes cloud agents on demand by looking at the 'infrastructure'
parameter passed into the methods of this class.
"""
# Default reasons which might be returned by this module
REASON_BAD_SECRET = 'bad secret'
REASON_BAD_VM_COUNT = 'bad vm count'
REASON_BAD_ARGUMENTS = 'bad arguments'
REASON_RESERVATION_NOT_FOUND = 'reservation_id not found'
REASON_NONE = 'none'
# Parameters required by InfrastructureManager
PARAM_RESERVATION_ID = 'reservation_id'
PARAM_INFRASTRUCTURE = 'infrastructure'
PARAM_NUM_VMS = 'num_vms'
# States a particular VM deployment could be in
STATE_PENDING = 'pending'
STATE_RUNNING = 'running'
STATE_FAILED = 'failed'
# A list of parameters required to query the InfrastructureManager about
# the state of a run_instances request.
DESCRIBE_INSTANCES_REQUIRED_PARAMS = ( PARAM_RESERVATION_ID, )
# A list of parameters required to initiate a VM deployment process
RUN_INSTANCES_REQUIRED_PARAMS = (
PARAM_INFRASTRUCTURE,
PARAM_NUM_VMS
)
# A list of parameters required to initiate a VM termination process
TERMINATE_INSTANCES_REQUIRED_PARAMS = ( PARAM_INFRASTRUCTURE, )
def __init__(self, params=None, blocking=False):
"""
Create a new InfrastructureManager instance. This constructor
accepts an optional boolean parameter which decides whether the
InfrastructureManager instance should operate in blocking mode
or not. A blocking InfrastructureManager does not return until
each requested run/terminate operation is complete. This mode
is useful for testing and verification purposes. In a real-world
deployment it's advisable to instantiate the InfrastructureManager
in the non-blocking mode as run/terminate operations could take
a rather long time to complete. By default InfrastructureManager
instances are created in the non-blocking mode.
Args
params A dictionary of parameters. Optional parameter. If
specified it must at least include the 'store_type' parameter.
blocking Whether to operate in blocking mode or not. Optional
and defaults to false.
"""
self.blocking = blocking
self.secret = utils.get_secret()
self.agent_factory = InfrastructureAgentFactory()
if params is not None:
store_factory = PersistentStoreFactory()
store = store_factory.create_store(params)
self.reservations = PersistentDictionary(store)
else:
self.reservations = PersistentDictionary()
def describe_instances(self, parameters, secret):
"""
Query the InfrastructureManager instance for details regarding
a set of virtual machines spawned in the past. This method accepts
a dictionary of parameters and a secret for authentication purposes.
The dictionary of parameters must include a 'reservation_id' parameter
which is used to reference past virtual machine deployments.
Args:
parameters A dictionary of parameters which contains a valid
'reservation_id' parameter. A valid 'reservation_id'
is an ID issued by the run_instances method of the
same InfrastructureManager object. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
If the provided secret key is valid and the parameters map contains
a valid 'reservation_id' parameter, this method will return a
dictionary containing information regarding the requested past
virtual machine deployment. This returned map contains several
keys including 'success', 'state', 'reason' and 'vm_info'. The value
of 'success' could be True of False depending on the outcome of the
virtual machine deployment process. If the value of 'success' happens
to be False, the 'reason' key would contain more details as to what
caused the deployment to fail. The 'state' key could contain a 'pending'
value or a 'running' value depending on the current state of the
virtual machine deployment. And finally the 'vm_info' key would point
to a another dictionary containing the IP addresses of the spawned virtual
machines. If the virtual machine deployment had failed or still in the
'pending' state, this key would contain the value None.
If this method receives an invalid key or an invalid 'reservation_id'
parameter, it will return a dictionary containing the keys 'success'
and 'reason' where 'success' would be set to False, and 'reason' is
set to a simple error message describing the cause of the error.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.DESCRIBE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
reservation_id = parameters[self.PARAM_RESERVATION_ID]
if self.reservations.has_key(reservation_id):
return self.reservations.get(reservation_id)
else:
return self.__generate_response(False, self.REASON_RESERVATION_NOT_FOUND)
def run_instances(self, parameters, secret):
"""
Start a new virtual machine deployment using the provided parameters. The
input parameter set must include an 'infrastructure' parameter which indicates
the exact cloud environment to use. Value of this parameter will be used to
instantiate a cloud environment specific agent which knows how to interact
with the specified cloud platform. The parameters map must also contain a
'num_vms' parameter which indicates the number of virtual machines that should
be spawned. In addition to that any parameters required to spawn VMs in the
specified cloud environment must be included in the parameters map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method will simply kick off the VM deployment process and return
immediately.
Args:
parameters A parameter map containing the keys 'infrastructure',
'num_vms' and any other cloud platform specific
parameters. Alternatively one may provide a valid
JSON string instead of a dictionary object.
secret A previously established secret
Returns:
If the secret is valid and all the required parameters are available in
the input parameter map, this method will return a dictionary containing
a special 'reservation_id' key. If the secret is invalid or a required
parameter is missing, this method will return a different map with the
key 'success' set to False and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
utils.log('Received a request to run instances.')
if self.secret != secret:
utils.log('Incoming secret {0} does not match the current secret {1} - '\
'Rejecting request.'.format(secret, self.secret))
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.RUN_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
num_vms = int(parameters[self.PARAM_NUM_VMS])
if num_vms <= 0:
utils.log('Invalid VM count: {0}'.format(num_vms))
return self.__generate_response(False, self.REASON_BAD_VM_COUNT)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters, BaseAgent.OPERATION_RUN)
except AgentConfigurationException as exception:
return self.__generate_response(False, str(exception))
reservation_id = utils.get_random_alphanumeric()
status_info = {
'success': True,
'reason': 'received run request',
'state': self.STATE_PENDING,
'vm_info': None
}
self.reservations.put(reservation_id, status_info)
utils.log('Generated reservation id {0} for this request.'.format(
reservation_id))
try:
if self.blocking:
self.__spawn_vms(agent, num_vms, parameters, reservation_id)
else:
thread.start_new_thread(self.__spawn_vms,
(agent, num_vms, parameters, reservation_id))
except AgentConfigurationException as exception:
status_info = {
'success' : False,
'reason' : str(exception),
'state' : self.STATE_FAILED,
'vm_info' : None
}
self.reservations.put(reservation_id, status_info)
utils.log('Updated reservation id {0} with failed status because: {1}' \
.format(reservation_id, str(exception)))
utils.log('Successfully started request {0}.'.format(reservation_id))
return self.__generate_response(True,
self.REASON_NONE, {'reservation_id': reservation_id})
def terminate_instances(self, parameters, secret):
"""
Terminate a group of virtual machines using the provided parameters.
The input parameter map must contain an 'infrastructure' parameter which
will be used to instantiate a suitable cloud agent. Any additional
environment specific parameters should also be available in the same
map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method simply starts the VM termination process and returns immediately.
Args:
parameters A dictionary of parameters containing the required
'infrastructure' parameter and any other platform
dependent required parameters. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
If the secret is valid and all the parameters required to successfully
start a termination process are present in the parameters dictionary,
this method will return a dictionary with the key 'success' set to
True. Otherwise it returns a dictionary with 'success' set to False
and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.TERMINATE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters,
BaseAgent.OPERATION_TERMINATE)
except AgentConfigurationException as exception:
return self.__generate_response(False, str(exception))
if self.blocking:
self.__kill_vms(agent, parameters)
else:
thread.start_new_thread(self.__kill_vms, (agent, parameters))
return self.__generate_response(True, self.REASON_NONE)
def attach_disk(self, parameters, disk_name, instance_id, secret):
""" Contacts the infrastructure named in 'parameters' and tells it to
attach a persistent disk to this machine.
Args:
parameters: A dict containing the credentials necessary to send requests
to the underlying cloud infrastructure.
disk_name: A str corresponding to the name of the persistent disk that
should be attached to this machine.
instance_id: A str naming the instance id that the disk should be attached
to (typically this machine).
secret: A str that authenticates the caller.
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
disk_location = agent.attach_disk(parameters, disk_name, instance_id)
return self.__generate_response(True, self.REASON_NONE,
{'location' : disk_location})
def __spawn_vms(self, agent, num_vms, parameters, reservation_id):
"""
Private method for starting a set of VMs
Args:
agent Infrastructure agent in charge of current operation
num_vms No. of VMs to be spawned
parameters A dictionary of parameters
reservation_id Reservation ID of the current run request
"""
status_info = self.reservations.get(reservation_id)
try:
security_configured = agent.configure_instance_security(parameters)
instance_info = agent.run_instances(num_vms, parameters,
security_configured)
ids = instance_info[0]
public_ips = instance_info[1]
private_ips = instance_info[2]
status_info['state'] = self.STATE_RUNNING
status_info['vm_info'] = {
'public_ips': public_ips,
'private_ips': private_ips,
'instance_ids': ids
}
utils.log('Successfully finished request {0}.'.format(reservation_id))
except AgentRuntimeException as exception:
status_info['state'] = self.STATE_FAILED
status_info['reason'] = str(exception)
self.reservations.put(reservation_id, status_info)
def __kill_vms(self, agent, parameters):
"""
Private method for stopping a set of VMs
Args:
agent Infrastructure agent in charge of current operation
parameters A dictionary of parameters
"""
agent.terminate_instances(parameters)
def __generate_response(self, status, msg, extra=None):
"""
Generate an infrastructure manager service response
Args:
status A boolean value indicating the status
msg A reason message (useful if this a failed operation)
extra Any extra fields to be included in the response (Optional)
Returns:
A dictionary containing the operation response
"""
utils.log("Sending success = {0}, reason = {1}".format(status, msg))
response = {'success': status, 'reason': msg}
if extra is not None:
for key, value in extra.items():
response[key] = value
return response
def __validate_args(self, parameters, secret):
"""
Validate the arguments provided by user.
Args:
parameters A dictionary (or a JSON string) provided by the client
secret Secret sent by the client
Returns:
Processed user arguments
Raises
TypeError If at least one user argument is not of the current type
"""
if type(parameters) != type('') and type(parameters) != type({}):
raise TypeError('Invalid data type for parameters. Must be a '
'JSON string or a dictionary.')
elif type(secret) != type(''):
raise TypeError('Invalid data type for secret. Must be a string.')
if type(parameters) == type(''):
parameters = json.loads(parameters)
return parameters, secret
class InfrastructureManager:
"""
InfrastructureManager class is the main entry point to the AppScale
Infrastructure Manager implementation. An instance of this class can
be used to start new virtual machines in a specified cloud environment
and terminate virtual machines when they are no longer required. Instances
of this class also keep track of the virtual machines spawned by them
and hence each InfrastructureManager instance can be queried to obtain
information about any virtual machines spawned by each of them in the
past.
This implementation is completely cloud infrastructure agnostic
and hence can be used to spawn/terminate instances on a wide range of
cloud (IaaS) environments. All the cloud environment specific operations
are delegated to a separate cloud agent and the InfrastructureManager
initializes cloud agents on demand by looking at the 'infrastructure'
parameter passed into the methods of this class.
"""
# Default reasons which might be returned by this module
REASON_BAD_SECRET = 'bad secret'
REASON_BAD_VM_COUNT = 'bad vm count'
REASON_BAD_ARGUMENTS = 'bad arguments'
REASON_RESERVATION_NOT_FOUND = 'reservation_id not found'
REASON_NONE = 'none'
# Parameters required by InfrastructureManager
PARAM_RESERVATION_ID = 'reservation_id'
PARAM_INFRASTRUCTURE = 'infrastructure'
PARAM_NUM_VMS = 'num_vms'
# States a particular VM deployment could be in
STATE_PENDING = 'pending'
STATE_RUNNING = 'running'
STATE_FAILED = 'failed'
# A list of parameters required to query the InfrastructureManager about
# the state of a run_instances request.
DESCRIBE_INSTANCES_REQUIRED_PARAMS = ( PARAM_RESERVATION_ID, )
# A list of parameters required to initiate a VM deployment process
RUN_INSTANCES_REQUIRED_PARAMS = (
PARAM_INFRASTRUCTURE,
PARAM_NUM_VMS
)
# A list of parameters required to initiate a VM termination process
TERMINATE_INSTANCES_REQUIRED_PARAMS = ( PARAM_INFRASTRUCTURE, )
def __init__(self, params=None, blocking=False):
"""
Create a new InfrastructureManager instance. This constructor
accepts an optional boolean parameter which decides whether the
InfrastructureManager instance should operate in blocking mode
or not. A blocking InfrastructureManager does not return until
each requested run/terminate operation is complete. This mode
is useful for testing and verification purposes. In a real-world
deployment it's advisable to instantiate the InfrastructureManager
in the non-blocking mode as run/terminate operations could take
a rather long time to complete. By default InfrastructureManager
instances are created in the non-blocking mode.
Args
params A dictionary of parameters. Optional parameter. If
specified it must at least include the 'store_type' parameter.
blocking Whether to operate in blocking mode or not. Optional
and defaults to false.
"""
self.blocking = blocking
self.secret = utils.get_secret()
self.agent_factory = InfrastructureAgentFactory()
if params is not None:
store_factory = PersistentStoreFactory()
store = store_factory.create_store(params)
self.reservations = PersistentDictionary(store)
else:
self.reservations = PersistentDictionary()
def describe_instances(self, parameters, secret):
"""
Query the InfrastructureManager instance for details regarding
a set of virtual machines spawned in the past. This method accepts
a dictionary of parameters and a secret for authentication purposes.
The dictionary of parameters must include a 'reservation_id' parameter
which is used to reference past virtual machine deployments.
Args:
parameters A dictionary of parameters which contains a valid
'reservation_id' parameter. A valid 'reservation_id'
is an ID issued by the run_instances method of the
same InfrastructureManager object. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
If the provided secret key is valid and the parameters map contains
a valid 'reservation_id' parameter, this method will return a
dictionary containing information regarding the requested past
virtual machine deployment. This returned map contains several
keys including 'success', 'state', 'reason' and 'vm_info'. The value
of 'success' could be True of False depending on the outcome of the
virtual machine deployment process. If the value of 'success' happens
to be False, the 'reason' key would contain more details as to what
caused the deployment to fail. The 'state' key could contain a 'pending'
value or a 'running' value depending on the current state of the
virtual machine deployment. And finally the 'vm_info' key would point
to a another dictionary containing the IP addresses of the spawned virtual
machines. If the virtual machine deployment had failed or still in the
'pending' state, this key would contain the value None.
If this method receives an invalid key or an invalid 'reservation_id'
parameter, it will return a dictionary containing the keys 'success'
and 'reason' where 'success' would be set to False, and 'reason' is
set to a simple error message describing the cause of the error.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.DESCRIBE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
reservation_id = parameters[self.PARAM_RESERVATION_ID]
if self.reservations.has_key(reservation_id):
return self.reservations.get(reservation_id)
else:
return self.__generate_response(False, self.REASON_RESERVATION_NOT_FOUND)
def run_instances(self, parameters, secret):
"""
Start a new virtual machine deployment using the provided parameters. The
input parameter set must include an 'infrastructure' parameter which indicates
the exact cloud environment to use. Value of this parameter will be used to
instantiate a cloud environment specific agent which knows how to interact
with the specified cloud platform. The parameters map must also contain a
'num_vms' parameter which indicates the number of virtual machines that should
be spawned. In addition to that any parameters required to spawn VMs in the
specified cloud environment must be included in the parameters map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method will simply kick off the VM deployment process and return
immediately.
Args:
parameters A parameter map containing the keys 'infrastructure',
'num_vms' and any other cloud platform specific
parameters. Alternatively one may provide a valid
JSON string instead of a dictionary object.
secret A previously established secret
Returns:
If the secret is valid and all the required parameters are available in
the input parameter map, this method will return a dictionary containing
a special 'reservation_id' key. If the secret is invalid or a required
parameter is missing, this method will return a different map with the
key 'success' set to False and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
utils.log('Received a request to run instances.')
if self.secret != secret:
utils.log('Incoming secret {0} does not match the current secret {1} - '\
'Rejecting request.'.format(secret, self.secret))
return self.__generate_response(False, self.REASON_BAD_SECRET)
utils.log('Request parameters are {0}'.format(parameters))
for param in self.RUN_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
num_vms = int(parameters[self.PARAM_NUM_VMS])
if num_vms <= 0:
utils.log('Invalid VM count: {0}'.format(num_vms))
return self.__generate_response(False, self.REASON_BAD_VM_COUNT)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters, BaseAgent.OPERATION_RUN)
except AgentConfigurationException as exception:
return self.__generate_response(False, exception.message)
reservation_id = utils.get_random_alphanumeric()
status_info = {
'success': True,
'reason': 'received run request',
'state': self.STATE_PENDING,
'vm_info': None
}
self.reservations.put(reservation_id, status_info)
utils.log('Generated reservation id {0} for this request.'.format(
reservation_id))
if self.blocking:
self.__spawn_vms(agent, num_vms, parameters, reservation_id)
else:
thread.start_new_thread(self.__spawn_vms,
(agent, num_vms, parameters, reservation_id))
utils.log('Successfully started request {0}.'.format(reservation_id))
return self.__generate_response(True,
self.REASON_NONE, {'reservation_id': reservation_id})
def terminate_instances(self, parameters, secret):
"""
Terminate a group of virtual machines using the provided parameters.
The input parameter map must contain an 'infrastructure' parameter which
will be used to instantiate a suitable cloud agent. Any additional
environment specific parameters should also be available in the same
map.
If this InfrastructureManager instance has been created in the blocking mode,
this method will not return until the VM deployment is complete. Otherwise
this method simply starts the VM termination process and returns immediately.
Args:
parameters A dictionary of parameters containing the required
'infrastructure' parameter and any other platform
dependent required parameters. Alternatively one
may provide a valid JSON string instead of a dictionary
object.
secret A previously established secret
Returns:
If the secret is valid and all the parameters required to successfully
start a termination process are present in the parameters dictionary,
this method will return a dictionary with the key 'success' set to
True. Otherwise it returns a dictionary with 'success' set to False
and 'reason' set to a simple error message.
Raises:
TypeError If the inputs are not of the expected types
ValueError If the input JSON string (parameters) cannot be parsed properly
"""
parameters, secret = self.__validate_args(parameters, secret)
if self.secret != secret:
return self.__generate_response(False, self.REASON_BAD_SECRET)
for param in self.TERMINATE_INSTANCES_REQUIRED_PARAMS:
if not utils.has_parameter(param, parameters):
return self.__generate_response(False, 'no ' + param)
infrastructure = parameters[self.PARAM_INFRASTRUCTURE]
agent = self.agent_factory.create_agent(infrastructure)
try:
agent.assert_required_parameters(parameters,
BaseAgent.OPERATION_TERMINATE)
except AgentConfigurationException as exception:
return self.__generate_response(False, exception.message)
if self.blocking:
self.__kill_vms(agent, parameters)
else:
thread.start_new_thread(self.__kill_vms, (agent, parameters))
return self.__generate_response(True, self.REASON_NONE)
def __spawn_vms(self, agent, num_vms, parameters, reservation_id):
"""
Private method for starting a set of VMs
Args:
agent Infrastructure agent in charge of current operation
num_vms No. of VMs to be spawned
parameters A dictionary of parameters
reservation_id Reservation ID of the current run request
"""
status_info = self.reservations.get(reservation_id)
try:
security_configured = agent.configure_instance_security(parameters)
instance_info = agent.run_instances(num_vms, parameters,
security_configured)
ids = instance_info[0]
public_ips = instance_info[1]
private_ips = instance_info[2]
status_info['state'] = self.STATE_RUNNING
status_info['vm_info'] = {
'public_ips': public_ips,
'private_ips': private_ips,
'instance_ids': ids
}
utils.log('Successfully finished request {0}.'.format(reservation_id))
except AgentRuntimeException as exception:
status_info['state'] = self.STATE_FAILED
status_info['reason'] = exception.message
self.reservations.put(reservation_id, status_info)
def __kill_vms(self, agent, parameters):
"""
Private method for stopping a set of VMs
Args:
agent Infrastructure agent in charge of current operation
parameters A dictionary of parameters
"""
agent.terminate_instances(parameters)
def __generate_response(self, status, msg, extra=None):
"""
Generate an infrastructure manager service response
Args:
status A boolean value indicating the status
msg A reason message (useful if this a failed operation)
extra Any extra fields to be included in the response (Optional)
Returns:
A dictionary containing the operation response
"""
response = {'success': status, 'reason': msg}
if extra is not None:
for key, value in extra.items():
response[key] = value
return response
def __validate_args(self, parameters, secret):
"""
Validate the arguments provided by user.
Args:
parameters A dictionary (or a JSON string) provided by the client
secret Secret sent by the client
Returns:
Processed user arguments
Raises
TypeError If at least one user argument is not of the current type
"""
if type(parameters) != type('') and type(parameters) != type({}):
raise TypeError('Invalid data type for parameters. Must be a '
'JSON string or a dictionary.')
elif type(secret) != type(''):
raise TypeError('Invalid data type for secret. Must be a string.')
if type(parameters) == type(''):
parameters = json.loads(parameters)
return parameters, secret
