Module Netamqp_channel

module Netamqp_channel: sig .. end

Manage AMQP channels

A channel is a data path between the client and the server. Several channels are multiplexed over a single TCP connection.

The client chooses the channel number identifying the channel. It is allowed to reuse channel numbers after closing a channel.

Channels are equipped with flow control: If the server demands to send content data slower, the client will respond to this. There is no configuration necessary to enable this feature.

Channels can be closed by either peer. It is possible to transmit error codes at channel close time.

exception Not_open

Raised if the channel is not known to be open on the client side

exception Error of string

An error occurred in channel management

type channel = int

A channel number is an int from 0 to 65535. Channel 0 is reserved, so channel numbers >= 1 can be used by the application.

type channel_obj

A channel management object

val open_e : Netamqp_connection.connection ->
       channel -> channel_obj Uq_engines.engine

Opens a channel on this connection. Fails if the channel is already known to be open on the client side.

val open_s : Netamqp_connection.connection ->
       channel -> channel_obj

Same as synchronous call

val open_next_e : Netamqp_connection.connection ->
       channel_obj Uq_engines.engine

val open_next_s : Netamqp_connection.connection -> channel_obj

Opens a channel, and chooses the channel number automatically.

val close_e : channel_obj -> unit Uq_engines.engine

Closes the channel. Raises Netamqp_channel.Not_open if the channel is not open.

val close_s : channel_obj -> unit

Same as synchronous call

val is_open : channel_obj -> bool

Whether a channel is open. Note that the peer can close channels at any time, so there is no guarantee that the channel is still open when is_open returns true.

Checking is_open is mainly useful for recovery after exceptions. Some exceptions close the channel, some do not.

val configure_sync_timeout : channel_obj -> float -> unit

Configure the timeout for synchronous request/response methods. Defaults to 60 seconds. When timing out the channel is closed, and all pending synchronous calls get the Netamqp_types.Timeout exception.

val sync_c2s_e : ?no_wait:Netamqp_endpoint.sync_server_to_client_method_t ->
       channel_obj ->
       Netamqp_endpoint.sync_client_initiated_method_t ->
       Netamqp_endpoint.data option ->
       (Netamqp_endpoint.sync_server_to_client_method_t *
        Netamqp_endpoint.data option)
       Uq_engines.engine

val sync_c2s_s : ?no_wait:Netamqp_endpoint.sync_server_to_client_method_t ->
       channel_obj ->
       Netamqp_endpoint.sync_client_initiated_method_t ->
       Netamqp_endpoint.data option ->
       Netamqp_endpoint.sync_server_to_client_method_t *
       Netamqp_endpoint.data option

Works very much like Netamqp_endpoint.sync_c2s_e, but the channel_obj can be passed, and the right timeout handling is done for this channel.

val number : channel_obj -> channel

Return the channel number

val connection : channel_obj -> Netamqp_connection.connection

Return the connection the channel uses

val endpoint : channel_obj -> Netamqp_endpoint.endpoint

Return the endpoint the channel uses

val event_system : channel_obj -> Unixqueue.event_system

Return the event system the channel uses

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