在GRPC Ruby客户端中中止GRPC服务器流连接

Question

将grpc定义的服务视为：

rpc :StreamingEvents, StreamingEventRequest, stream(StreamingEventResponse)

并利用客户端连接到此服务类似于：

call = stub.streaming_events(StreamingEventRequest.new)

call.each do |response|
  pp response
end

如果我们要在一个单独的线程中生成调用，那么处理终止一个永远运行、我们不想再使用的grpc连接的正确方法是什么？是否有任何连接或流控制方法可以调用？

Answer 1

挖掘源代码并拆解所有这些是如何工作的。如果您想使用流控制做任何高级工作，您必须传入return_op参数以接收操作符对象来控制流。这是一些示例代码：

传球方法论：

op = stub.streaming_events(StreamingEventRequest.new, return_op: true) do |response|
  pp response
end

t = Thread.new do
  op.execute
rescue GRPC::Cancelled => e
  puts "this will terminate with an exception when we hit cancel - #{e}"
end

# controls for the operation
op.status
op.cancelled?
op.cancel # terminates connection and raises GRPC::Cancelled in the thread.

枚举器示例：

op = stub.streaming_events(StreamingEventRequest.new, return_op: true)

t = Thread.new do
  call = op.execute
  call.each do |response|
    pp response
  end
rescue GRPC::Cancelled => e
  puts "this will terminate with an exception when we hit cancel - #{e}"
end

# controls for the operation
op.status
op.cancelled?
op.cancel # terminates connection and raises GRPC::Cancelled in the thread.