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"""Entry points into the Crust layer of RPC Framework."""

import six

from grpc.framework.common import cardinality
from grpc.framework.common import style
from grpc.framework.crust import _calls
from grpc.framework.crust import _service
from grpc.framework.interfaces.base import base
from grpc.framework.interfaces.face import face


class _BaseServicer(base.Servicer):

  def __init__(self, adapted_methods, adapted_multi_method):
    self._adapted_methods = adapted_methods
    self._adapted_multi_method = adapted_multi_method

  def service(self, group, method, context, output_operator):
    adapted_method = self._adapted_methods.get((group, method), None)
    if adapted_method is not None:
      return adapted_method(output_operator, context)
    elif self._adapted_multi_method is not None:
      try:
        return self._adapted_multi_method(
            group, method, output_operator, context)
      except face.NoSuchMethodError:
        raise base.NoSuchMethodError(None, None)
    else:
      raise base.NoSuchMethodError(None, None)


class _UnaryUnaryMultiCallable(face.UnaryUnaryMultiCallable):

  def __init__(self, end, group, method, pool):
    self._end = end
    self._group = group
    self._method = method
    self._pool = pool

  def __call__(
      self, request, timeout, metadata=None, with_call=False,
      protocol_options=None):
    return _calls.blocking_unary_unary(
        self._end, self._group, self._method, timeout, with_call,
        protocol_options, metadata, request)

  def future(self, request, timeout, metadata=None, protocol_options=None):
    return _calls.future_unary_unary(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request)

  def event(
      self, request, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_unary_unary(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request, receiver, abortion_callback, self._pool)


class _UnaryStreamMultiCallable(face.UnaryStreamMultiCallable):

  def __init__(self, end, group, method, pool):
    self._end = end
    self._group = group
    self._method = method
    self._pool = pool

  def __call__(self, request, timeout, metadata=None, protocol_options=None):
    return _calls.inline_unary_stream(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request)

  def event(
      self, request, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_unary_stream(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request, receiver, abortion_callback, self._pool)


class _StreamUnaryMultiCallable(face.StreamUnaryMultiCallable):

  def __init__(self, end, group, method, pool):
    self._end = end
    self._group = group
    self._method = method
    self._pool = pool

  def __call__(
      self, request_iterator, timeout, metadata=None,
      with_call=False, protocol_options=None):
    return _calls.blocking_stream_unary(
        self._end, self._group, self._method, timeout, with_call,
        protocol_options, metadata, request_iterator, self._pool)

  def future(
      self, request_iterator, timeout, metadata=None, protocol_options=None):
    return _calls.future_stream_unary(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request_iterator, self._pool)

  def event(
      self, receiver, abortion_callback, timeout, metadata=None,
      protocol_options=None):
    return _calls.event_stream_unary(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, receiver, abortion_callback, self._pool)


class _StreamStreamMultiCallable(face.StreamStreamMultiCallable):

  def __init__(self, end, group, method, pool):
    self._end = end
    self._group = group
    self._method = method
    self._pool = pool

  def __call__(
      self, request_iterator, timeout, metadata=None, protocol_options=None):
    return _calls.inline_stream_stream(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, request_iterator, self._pool)

  def event(
      self, receiver, abortion_callback, timeout, metadata=None,
      protocol_options=None):
    return _calls.event_stream_stream(
        self._end, self._group, self._method, timeout, protocol_options,
        metadata, receiver, abortion_callback, self._pool)


class _GenericStub(face.GenericStub):
  """An face.GenericStub implementation."""

  def __init__(self, end, pool):
    self._end = end
    self._pool = pool

  def blocking_unary_unary(
      self, group, method, request, timeout, metadata=None,
      with_call=None, protocol_options=None):
    return _calls.blocking_unary_unary(
        self._end, group, method, timeout, with_call, protocol_options,
        metadata, request)

  def future_unary_unary(
      self, group, method, request, timeout, metadata=None,
      protocol_options=None):
    return _calls.future_unary_unary(
        self._end, group, method, timeout, protocol_options, metadata, request)

  def inline_unary_stream(
      self, group, method, request, timeout, metadata=None,
      protocol_options=None):
    return _calls.inline_unary_stream(
        self._end, group, method, timeout, protocol_options, metadata, request)

  def blocking_stream_unary(
      self, group, method, request_iterator, timeout, metadata=None,
      with_call=None, protocol_options=None):
    return _calls.blocking_stream_unary(
        self._end, group, method, timeout, with_call, protocol_options,
        metadata, request_iterator, self._pool)

  def future_stream_unary(
      self, group, method, request_iterator, timeout, metadata=None,
      protocol_options=None):
    return _calls.future_stream_unary(
        self._end, group, method, timeout, protocol_options, metadata,
        request_iterator, self._pool)

  def inline_stream_stream(
      self, group, method, request_iterator, timeout, metadata=None,
      protocol_options=None):
    return _calls.inline_stream_stream(
        self._end, group, method, timeout, protocol_options, metadata,
        request_iterator, self._pool)

  def event_unary_unary(
      self, group, method, request, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_unary_unary(
        self._end, group, method, timeout, protocol_options, metadata, request,
        receiver, abortion_callback, self._pool)

  def event_unary_stream(
      self, group, method, request, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_unary_stream(
        self._end, group, method, timeout, protocol_options, metadata, request,
        receiver, abortion_callback, self._pool)

  def event_stream_unary(
      self, group, method, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_stream_unary(
        self._end, group, method, timeout, protocol_options, metadata, receiver,
        abortion_callback, self._pool)

  def event_stream_stream(
      self, group, method, receiver, abortion_callback, timeout,
      metadata=None, protocol_options=None):
    return _calls.event_stream_stream(
        self._end, group, method, timeout, protocol_options, metadata, receiver,
        abortion_callback, self._pool)

  def unary_unary(self, group, method):
    return _UnaryUnaryMultiCallable(self._end, group, method, self._pool)

  def unary_stream(self, group, method):
    return _UnaryStreamMultiCallable(self._end, group, method, self._pool)

  def stream_unary(self, group, method):
    return _StreamUnaryMultiCallable(self._end, group, method, self._pool)

  def stream_stream(self, group, method):
    return _StreamStreamMultiCallable(self._end, group, method, self._pool)


class _DynamicStub(face.DynamicStub):
  """An face.DynamicStub implementation."""

  def __init__(self, end, group, cardinalities, pool):
    self._end = end
    self._group = group
    self._cardinalities = cardinalities
    self._pool = pool

  def __getattr__(self, attr):
    method_cardinality = self._cardinalities.get(attr)
    if method_cardinality is cardinality.Cardinality.UNARY_UNARY:
      return _UnaryUnaryMultiCallable(self._end, self._group, attr, self._pool)
    elif method_cardinality is cardinality.Cardinality.UNARY_STREAM:
      return _UnaryStreamMultiCallable(self._end, self._group, attr, self._pool)
    elif method_cardinality is cardinality.Cardinality.STREAM_UNARY:
      return _StreamUnaryMultiCallable(self._end, self._group, attr, self._pool)
    elif method_cardinality is cardinality.Cardinality.STREAM_STREAM:
      return _StreamStreamMultiCallable(
          self._end, self._group, attr, self._pool)
    else:
      raise AttributeError('_DynamicStub object has no attribute "%s"!' % attr)


def _adapt_method_implementations(method_implementations, pool):
  adapted_implementations = {}
  for name, method_implementation in six.iteritems(method_implementations):
    if method_implementation.style is style.Service.INLINE:
      if method_implementation.cardinality is cardinality.Cardinality.UNARY_UNARY:
        adapted_implementations[name] = _service.adapt_inline_unary_unary(
            method_implementation.unary_unary_inline, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.UNARY_STREAM:
        adapted_implementations[name] = _service.adapt_inline_unary_stream(
            method_implementation.unary_stream_inline, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.STREAM_UNARY:
        adapted_implementations[name] = _service.adapt_inline_stream_unary(
            method_implementation.stream_unary_inline, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.STREAM_STREAM:
        adapted_implementations[name] = _service.adapt_inline_stream_stream(
            method_implementation.stream_stream_inline, pool)
    elif method_implementation.style is style.Service.EVENT:
      if method_implementation.cardinality is cardinality.Cardinality.UNARY_UNARY:
        adapted_implementations[name] = _service.adapt_event_unary_unary(
            method_implementation.unary_unary_event, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.UNARY_STREAM:
        adapted_implementations[name] = _service.adapt_event_unary_stream(
            method_implementation.unary_stream_event, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.STREAM_UNARY:
        adapted_implementations[name] = _service.adapt_event_stream_unary(
            method_implementation.stream_unary_event, pool)
      elif method_implementation.cardinality is cardinality.Cardinality.STREAM_STREAM:
        adapted_implementations[name] = _service.adapt_event_stream_stream(
            method_implementation.stream_stream_event, pool)
  return adapted_implementations


def servicer(method_implementations, multi_method_implementation, pool):
  """Creates a base.Servicer.

  It is guaranteed that any passed face.MultiMethodImplementation will
  only be called to service an RPC if there is no
  face.MethodImplementation for the RPC method in the passed
  method_implementations dictionary.

  Args:
    method_implementations: A dictionary from RPC method name to
      face.MethodImplementation object to be used to service the named
      RPC method.
    multi_method_implementation: An face.MultiMethodImplementation to be
      used to service any RPCs not serviced by the
      face.MethodImplementations given in the method_implementations
      dictionary, or None.
    pool: A thread pool.

  Returns:
    A base.Servicer that services RPCs via the given implementations.
  """
  adapted_implementations = _adapt_method_implementations(
      method_implementations, pool)
  if multi_method_implementation is None:
    adapted_multi_method_implementation = None
  else:
    adapted_multi_method_implementation = _service.adapt_multi_method(
        multi_method_implementation, pool)
  return _BaseServicer(
      adapted_implementations, adapted_multi_method_implementation)


def generic_stub(end, pool):
  """Creates an face.GenericStub.

  Args:
    end: A base.End.
    pool: A futures.ThreadPoolExecutor.

  Returns:
    A face.GenericStub that performs RPCs via the given base.End.
  """
  return _GenericStub(end, pool)


def dynamic_stub(end, group, cardinalities, pool):
  """Creates an face.DynamicStub.

  Args:
    end: A base.End.
    group: The group identifier for all RPCs to be made with the created
      face.DynamicStub.
    cardinalities: A dict from method identifier to cardinality.Cardinality
      value identifying the cardinality of every RPC method to be supported by
      the created face.DynamicStub.
    pool: A futures.ThreadPoolExecutor.

  Returns:
    A face.DynamicStub that performs RPCs via the given base.End.
  """
  return _DynamicStub(end, group, cardinalities, pool)