AMQP Subscriber | X4Documentation

The adapter manages subscriptions to an AMQP queue and defines the process to be executed.

Properties

Operation

Defines the operation executed by the adapter

Possible values:

Subscribe: Subscribe to an AMQP queue and define the process to be executed
Required parameters are host, port, username, password, queue and process. The parameters can also be provided via a configuration file, which is specified within the parameter storedConfig.
Unsubscribe: Unsubscribe from an AMQP queue
Required parameters are username and queue. The parameters can also be provided via a configuration file, which is specified within the parameter storedConfig.

Parameters

`storedConfig`	Identifier of the configuration provided in `amqpconfig.xml` Possible values: Any string containing the configuration identifier, e.g. `queueEmployeesConfig`
`host`	AMQP server host Possible values: Server host, e.g. `localhost`
`port`	Dedicated AMQP port in the server Possible values: AMQP port number, e.g. `5672`
`username`	Name of the user subscribing or unsubscribing to a topic Possible values: Any string containing the user name, e.g. `user`
`password`	Password associated to the user Possible values: Any string containing the corresponding password, e.g. `p4ssw0rd`
`queue`	Queue where the message is subscribed or unsubscribed Possible values: Any string containing the queue name, e.g. `employees`
`container`	Container where the queue is placed Possible values: Any string containing the container name, e.g. `employeesContainer`
`qos`	Quality of Service of the message Possible values: `AT_MOST_ONCE`: The message is delivered at most once, or it is not delivered at all. `AT_LEAST_ONCE`: The message is delivered at least once. `EXACTLY_ONCE`: The message is delivered only once. The default value is `AT_MOST_ONCE`, if the attribute `qos` is not specified.
`useSsl`	Enable SSL encryption Possible values: `true` / `false` (default)
`useSasl`	Activate SASL Authentication Possible values: `true` / `false` (default)
`mechanism`	SASL mechanism of the remote endpoint. Mögliche Werte: `PLAIN`: All data is exchanged in cleartext (Default). `ANONYMOUS`: The service can be used for unauthenticated guest access. `CRAM-MDS`: Prevents sending the password in cleartext. `Digest-MDS`: Additional parameters can be used for integrity checks.
`process`	Path of the Technical Process executed as soon as a message is received Possible values: Process path, e.g. `x4db://1/Project/Processes/process.wrf`

Status values

`0`	The operation was executed successfully (no output is generated)
`-1`	An error occurred during the operation's execution (no output is generated)

Configuration

To provide the needed information a configuration file with a specified structure can be used, which is loaded at server startup. The configuration file amqpconfig.xml must be stored under the server path X4DB/0.

The file has the following structure:

amqpconfig.xml

XML

<?xml version='1.0' encoding='UTF-8'?>
<RootElement>
    <AMQPConfig name="queueEmployeesConfig">
        <Server host="localhost" port="5672" useSsl="false"/>
        <Client user="user" password="p4ssw0rd"/>
        <Queue container="employeesContainer" name="employees" qos="AT_LEAST_ONCE"/>
    </AMQPConfig>
</RootElement>