Outgoing connections - AMQP

Overview

Used to create, update, delete and browse through outgoing AMQP connections.

Each outgoing connection represents a link through which AMQP messages are sent by Zato services.

Creating or updating a connection (re-)establishes a link to an AMQP broker and there are as many connectors and connections to any broker as there are active outgoing connections and channels in a cluster.

For instance, if there is 1 AMQP definition and 5 outgoing connections using it, there will be 5 connector processes started in a cluster each maintaining 1 connection to the broker pointed to by the definition.

Sending messages to a remote broker is an asynchronous activity - messages are not rolled back to Zato services if there are any errors along.

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Create and Edit

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Header Notes
Name Connection name
Active Documented below
Definition AMQP definition to read basic connection information from
Delivery mode Whether messages send should be persistent by default or not
Priority (Optional) Default message priority. 9 is the highest one.s
Content type (Optional) Default content type for messages sent
Encoding (Optional) Default message encoding
Expiration (Optional) After how many milliseconds messages should expire
User ID (Optional) User ID sending the message (consult AMQP spec)
App ID (Optional) App ID sending the message (consult AMQP spec)

Each optional value can be overridden by a service making use of the outgoing connection.

Delete

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Stops the underlying connector and deletes the connection from ODB.

The ‘Active’ flag

If an outgoing connection is made inactive and there are services still making use of it, the messages services send will be lost.

You need to ensure no service is able to reach an outgoing connection before it’s turned off - otherwise you will lose messages.

Also an inactive outgoing AMQP connection closes its underlying link to a broker but the connector’s process continues to run.