Initial checkin of gRPC to third_party/

third_party/grpc/src/python/grpcio/grpc/framework/core/_emission.py

Index: third_party/grpc/src/python/grpcio/grpc/framework/core/_emission.py
diff --git a/third_party/grpc/src/python/grpcio/grpc/framework/core/_emission.py b/third_party/grpc/src/python/grpcio/grpc/framework/core/_emission.py
new file mode 100644
index 0000000000000000000000000000000000000000..8ab59dc3e585346a6f333560890053191c7228a1
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+++ b/third_party/grpc/src/python/grpcio/grpc/framework/core/_emission.py
@@ -0,0 +1,100 @@
+# Copyright 2015, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""State and behavior for handling emitted values."""
+
+from grpc.framework.core import _interfaces
+from grpc.framework.core import _utilities
+from grpc.framework.interfaces.base import base
+
+
+class EmissionManager(_interfaces.EmissionManager):
+  """An EmissionManager implementation."""
+
+  def __init__(
+      self, lock, termination_manager, transmission_manager,
+      expiration_manager):
+    """Constructor.
+
+    Args:
+      lock: The operation-wide lock.
+      termination_manager: The _interfaces.TerminationManager for the operation.
+      transmission_manager: The _interfaces.TransmissionManager for the
+        operation.
+      expiration_manager: The _interfaces.ExpirationManager for the operation.
+    """
+    self._lock = lock
+    self._termination_manager = termination_manager
+    self._transmission_manager = transmission_manager
+    self._expiration_manager = expiration_manager
+    self._ingestion_manager = None
+
+    self._initial_metadata_seen = False
+    self._payload_seen = False
+    self._completion_seen = False
+
+  def set_ingestion_manager(self, ingestion_manager):
+    """Sets the ingestion manager with which this manager will cooperate.
+
+    Args:
+      ingestion_manager: The _interfaces.IngestionManager for the operation.
+    """
+    self._ingestion_manager = ingestion_manager
+
+  def advance(
+      self, initial_metadata=None, payload=None, completion=None,
+      allowance=None):
+    initial_metadata_present = initial_metadata is not None
+    payload_present = payload is not None
+    completion_present = completion is not None
+    allowance_present = allowance is not None
+    with self._lock:
+      if self._termination_manager.outcome is None:
+        if (initial_metadata_present and (
+                self._initial_metadata_seen or self._payload_seen or
+                self._completion_seen) or
+            payload_present and self._completion_seen or
+            completion_present and self._completion_seen or
+            allowance_present and allowance <= 0):
+          outcome = _utilities.Outcome(
+              base.Outcome.Kind.LOCAL_FAILURE, None, None)
+          self._termination_manager.abort(outcome)
+          self._transmission_manager.abort(outcome)
+          self._expiration_manager.terminate()
+        else:
+          self._initial_metadata_seen |= initial_metadata_present
+          self._payload_seen |= payload_present
+          self._completion_seen |= completion_present
+          if completion_present:
+            self._termination_manager.emission_complete()
+            self._ingestion_manager.local_emissions_done()
+          self._transmission_manager.advance(
+              initial_metadata, payload, completion, allowance)
+          if allowance_present:
+            self._ingestion_manager.add_local_allowance(allowance)