| #-- |
| # Licensed to the Apache Software Foundation (ASF) under one |
| # or more contributor license agreements. See the NOTICE file |
| # distributed with this work for additional information |
| # regarding copyright ownership. The ASF licenses this file |
| # to you under the Apache License, Version 2.0 (the |
| # "License"); you may not use this file except in compliance |
| # with the License. You may obtain a copy of the License at |
| # |
| # http://www.apache.org/licenses/LICENSE-2.0 |
| # |
| # Unless required by applicable law or agreed to in writing, |
| # software distributed under the License is distributed on an |
| # "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| # KIND, either express or implied. See the License for the |
| # specific language governing permissions and limitations |
| # under the License. |
| #++ |
| |
| module Qpid::Proton |
| |
| # The receiving endpoint. |
| # |
| # @see Sender |
| # |
| class Receiver < Link |
| |
| # @private |
| include Util::SwigHelper |
| |
| # @private |
| PROTON_METHOD_PREFIX = "pn_link" |
| |
| # @!attribute drain |
| # |
| # The drain mode. |
| # |
| # If a receiver is in drain mode, then the sending endpoint of a link must |
| # immediately use up all available credit on the link. If this is not |
| # possible, the excess credit must be returned by invoking #drained. |
| # |
| # Only the receiving endpoint can set the drain mode. |
| # |
| # @return [Boolean] True if drain mode is set. |
| # |
| proton_accessor :drain |
| |
| # @!attribute [r] draining? |
| # |
| # Returns if a link is currently draining. |
| # |
| # A link is defined to be draining when drain mode is set to true and |
| # the sender still has excess credit. |
| # |
| # @return [Boolean] True if the receiver is currently draining. |
| # |
| proton_caller :draining? |
| |
| # Grants credit for incoming deliveries. |
| # |
| # @param n [Fixnum] The amount to increment the link credit. |
| # |
| def flow(n) |
| Cproton.pn_link_flow(@impl, n) |
| end |
| |
| # Allows receiving up to the specified limit of data from the remote |
| # endpoint. |
| # |
| # Note that large messages can be streamed across the network, so just |
| # because there is no data to read does not imply the message is complete. |
| # |
| # To ensure the entirety of the message data has been read, either call |
| # #receive until nil is returned, or verify that #partial? is false and |
| # Delivery#pending is 0. |
| # |
| # @param limit [Fixnum] The maximum bytes to receive. |
| # |
| # @return [Fixnum, nil] The number of bytes received, or nil if the end of |
| # the stream was reached.t |
| # |
| # @see Deliver#pending To see how much buffer space is needed. |
| # |
| # @raise [LinkError] If an error occurs. |
| # |
| def receive(limit) |
| (n, bytes) = Cproton.pn_link_recv(@impl, limit) |
| return nil if n == Qpid::Proton::Error::EOS |
| raise LinkError.new("[#{n}]: #{Cproton.pn_link_error(@impl)}") if n < 0 |
| return bytes |
| end |
| |
| end |
| |
| end |