Receiving and Sending

The library provides high-level and low-level APIs for receiving and sending.

Receiving

The sockets that can receive messages extends from io.fmq.socket.ConsumerSocket.

The io.fmq.frame.FrameDecoder is a typeclass that provides a conversion from Array[Byte] to A.
There are two predefined instances: FrameDecoder[Array[Byte]] and FrameDecoder[String].

Low-level API

There are several low-level methods:

1. def receive[A: FrameDecoder]: F[A]
   Receives a single message. Blocks indefinitely until a message arrives. You should call manually the hasReceiveMore method to verify that message is multipart or not.

2. def receiveNoWait[A: FrameDecoder]: F[Option[A]]
   Tries to receive a single message immediately (without blocking). If message is not available returns None.

3. def hasReceiveMore: F[Boolean]
   Returns true if message is multipart.

High-level API

The def receiveFrame[A: FrameDecoder]: F[Frame[A]] blocks indefinitely until a message arrives.
Consumes a multipart message automatically. The method returns Frame.Multipart if message is multipart, otherwise returns Frame.Single.

Sending

The sockets that can send messages extends from io.fmq.socket.ProducerSocket.

The io.fmq.frame.FrameEncoder is a typeclass that provides a conversion from A to Array[Byte].
There are two predefined instances: FrameEncoder[Array[Byte]] and FrameEncoder[String].

Low-level API

There are several low-level methods:

1. def send[A: FrameEncoder](value: A): F[Unit]
   Queues a message to be sent. The data is either a single-part message by itself, or the last part of a multi-part message.

2. def sendMore[A: FrameEncoder](value: A): F[Unit]
   Queues a multi-part message to be sent.

High-level API

The def sendFrame[A: FrameEncoder](frame: Frame[A]): F[Unit] queues a message to be sent. Sends a multipart message automatically.