RabbitMQConnector

Input

This transformer accepts any feature.

Output

The output of this transformer will vary depending on the action performed. Message data and metadata are presented as feature attributes.

After a Receive action, output features represent messages received from the broker.
After a Send action, output features represent messages sent to the broker.
After a Count action, output the number of messages in a queue.
After an Acknowledge action, set messages marked as acknowledged. There are no output features.

Initiator

The incoming feature is output through this port.

Features that cause the operation to fail are output through this port. An fme_rejection_code attribute, having the value ERROR_DURING_PROCESSING, will be added, along with a more descriptive fme_rejection_message attribute which contains more specific details as to the reason for the failure.

Note If a feature comes in to the RabbitMQConnector already having a value for fme_rejection_code, this value will be removed.

Rejected Feature Handling: can be set to either terminate the translation or continue running when it encounters a rejected feature. This setting is available both as a default FME option and as a workspace parameter.

Authentication

Credential Source

Using a web connection integrates best with FME, but in some cases, you may wish to use one of the other sources.

Web Connection - use a RabbitMQ web connection with stored credentials in the FME web connections database
Embedded - embed credentials as parameters in the transformer

Account

Available when the credential source is Web Connection. To create a RabbitMQ connection, click the Account drop-down box and select Add Web Connection....

The connection can then be managed via Tools > FME Options > Web Connections.

Embedded Credentials

Host	The endpoint of the RabbitMQ broker.
Virtual Host	The name of the virtual host used for multi-tenant brokers. Default is /.
Broker Port	The port to connect to the broker. Default is 5672.
Web Port	The port to connect to the RabbitMQ HTTP API. This is the same port for the admin web GUI. Default is 15672
Enable SSL/TLS	Whether to use a secure connection when connecting to the broker.
Verify Certificates	Whether to verify SSL/TLS certificates. Only choose No if there are expected certificate errors.
User Name, Password	The username and password to use when connecting to the broker.

Request

Action

The type of operation to perform. Choices are:

Acknowledge
Count Messages
Receive
Send

Parameters - Acknowledge Action

Acknowledge Options

Receiving Connector Id	The _connector_id attribute received from the Receive Action. Used for determining the message to acknowledge.
Delivery Tag	The _delivery_tag attribute received from the Receive Action. Used for determining the message to acknowledge.
Multiple Messages	If Yes, acknowledge all messages prior to the current message.

Parameters - Count Messages Action

Count Messages Options

Queue

The queue to count waiting messages.

Parameters - Receive Action

Routing

Exchange Type	The exchange Fanout: Messages are sent to all queues that are bound to the exchange. Direct: Messages are sent to all queues bound to the exchange via the routing key. Topic: Messages are set to queues bound to a routing key via a pattern.
Exchange	The exchange name consists of a non-empty sequence of these characters: letters, digits, hyphen, underscore, period, or colon.
Routing Key	The name used to route messages from exchanges to queues.
Queue	The queue name. If empty, the broker will create a unique queue name.
Queue Type	The type of RabbitMQ queue: Classic (default) Quorum Stream

Receive Options

Receive Mode

Two message receiving options are available:

Stream: The connector continues to receive messages indefinitely. The translation needs to be terminated in order to stop reception.
Batch: Only a given number of messages are received before the connection is closed.

Batch Size

In Batch mode, specifies the number of messages to read per batch.

Advanced Properties

Auto Acknowledge	Three Acknowledgment modes are available. Default is No. No: The messages must be acknowledged in another transformer. The channel to the broker will stay open until the messages are acknowledged. Use the outputted _connector_id and _delivery_tag attributes in the acknowledgment transformer. Server-side: The broker will send messages without expecting any acknowledgments in return. If using Batch receive mode with a Batch Size smaller than the number of queued messages, the remaining messages will be discarded. For information on data safety with RabbitMQ auto-acknowledgement, see: https://www.rabbitmq.com/docs/confirms#acknowledgement-modes Client-side: The transformer will automatically send an acknowledgment for every message. This option is disabled if the Queue Type is Stream, as consumed messages will always be acknowledged.
Declare Exchange	Whether to declare the exchange.
Exchange Properties	Properties to apply to the exchange: Auto_Delete: The exchange is deleted after the consumer cancels or disconnects. Durable: Survive reboots of the broker. If not selected, the exchange is transient. A transient exchange is deleted on reboot. Metadata of a durable exchange is stored on disk, while metadata of transient exchange is stored in memory.
Queue Properties	Properties to apply to the queue when Queue Type is Classic: Auto_Delete: The queue is deleted after the consumer cancels or disconnects. Durable: Survive reboots of the broker. If not selected, the queue is transient. A transient queue message is deleted on reboot. Metadata of a durable queue is stored on disk, while metadata of transient queue is stored in memory. As of fpkg-rabbitmq 3.1.0, new classic queues on RabbitMQ 4.0+ must be durable. For more information on RabbitMQ queues see: https://www.rabbitmq.com/queues.html
Offset Mode	If Queue Type is Stream, specify where in the stream to begin reading messages. First: Begin reading messages from the first message of the stream. Last: Begin reading messages from the last message of the stream. Next: Wait for incoming messages. Value: See Offset Value. Timestamp: See Offset Timestamp.
Offset Value	If Offset Mode is Value, specify either an integer representing an offset of an existing message in the stream queue, or an ‘Interval’ string that begins with an integer and ends with a valid unit (Y,M,D,h,m,s). See the Offset and Interval options in https://www.rabbitmq.com/docs/streams#consuming for details.
Offset Timestamp	If Offset Mode is Timestamp, specify a date and time representing a point in time to start reading messages from. This date and time must be specified in Coordinated Universal Time (UTC). See the Timestamp option in https://www.rabbitmq.com/docs/streams#consuming for details.
Stream Properties	Properties to apply to the queue when Queue Type is Stream: x-max-age: Sets the maximum age of the stream. x-max-length-bytes: Sets the maximum size of the stream in bytes. x-stream-max-segment-size-bytes: Sets the maximum size of a stream segment file in bytes. If a queue already exists, specified properties must match existing properties. For more information on RabbitMQ stream queue properties, see: https://www.rabbitmq.com/docs/streams#declaring.

Parameters - Send Action

Routing

Exchange Type

The exchange

Fanout: Messages are sent to all queues that are bound to the exchange.
Direct: Messages are sent to all queues bound to the exchange via the routing key.
Topic: Messages are set to queues bound to a routing key via a pattern.

Exchange

The exchange name consists of a non-empty sequence of these characters: letters, digits, hyphen, underscore, period, or colon.

Routing Key

The name used to route messages from exchanges to queues.

If Exchange Type is Direct and Exchange is empty, Declare Queue must be Yes and the Routing Key must be identical to Queue.

Send Options

Payload	The content of the message. This is often JSON, but can be any string, binary, integer or floating-point value.
Delivery Mode	Default: Messages are lost after a broker restart. Persistent: Messages are saved to disk and survive a broker restart.

Advanced Properties

Declare Exchange	Whether to declare the exchange.
Exchange Properties	Properties to apply to the exchange Auto_Delete: The exchange is deleted after the consumer cancels or disconnects. Durable: Survive reboots of the broker. If not selected, the exchange is transient. A transient exchange is deleted on reboot. Metadata of a durable exchange is stored on disk, while metadata of transient exchange is stored in memory.
Declare Queue	Whether to declare the queue.
Queue	The queue to use.
Queue Type	The type of RabbitMQ queue: Classic (default) Quorum Stream
Queue Properties	Properties to apply to the queue when Queue Type is Classic: Auto_Delete: The queue is deleted after the consumer cancels or disconnects. Durable: Survive reboots of the broker. If not selected, the queue is transient. A transient queue message is deleted on reboot. Metadata of a durable queue is stored on disk, while metadata of transient queue is stored in memory. As of fpkg-rabbitmq 3.1.0, new classic queues on RabbitMQ 4.0+ must be durable. For more information on RabbitMQ queues, see: https://www.rabbitmq.com/queues.html
Message Properties	Additional message properties settable. The following keys are valid: content_type content_encoding priority correlation_id reply_to expiration message_id timestamp type user_id app_id cluster_id
Stream Properties	Properties to apply to the queue when Queue Type is Stream: x-max-age: Sets the maximum age of the stream. x-max-length-bytes: Sets the maximum size of the stream in bytes. x-stream-max-segment-size-bytes: Sets the maximum size of a stream segment file in bytes. If a queue already exists, specified properties must match existing properties. For more information on RabbitMQ stream queue properties, see: https://www.rabbitmq.com/docs/streams#declaring.

Output Attributes

The following attributes can be selected for inclusion on the output features. Each output feature represents a message that was either sent or received.

_delivery_tag	Used to identify the message for acknowledgment.
_payload	The message payload. UTF-8 string if possible to decode, otherwise binary or numeric.
_consumer_tag	Used to identify the consumer.
_exchange	The exchange that the message was routed through.
_headers	A list of name/value pairs of headers on the message.
_properties	A list of name/value pairs of additional message properties.
_redelivered	True if a message is delivered but not fully acknowledged and re-queued.
_routing_key	The routing key used to route the message.

How to Set Parameter Values

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters.

Using the Text Editor

The Text Editor provides a convenient way to construct text strings (including regular expressions) from various data sources, such as attributes, parameters, and constants, where the result is used directly inside a parameter.

Text Editor

Using the Arithmetic Editor

The Arithmetic Editor provides a convenient way to construct math expressions from various data sources, such as attributes, parameters, and feature functions, where the result is used directly inside a parameter.

Arithmetic Editor

Conditional Values

Set values depending on one or more test conditions that either pass or fail.

Parameter Condition Definition Dialog

Content

Expressions and strings can include a number of functions, characters, parameters, and more.

When setting values - whether entered directly in a parameter or constructed using one of the editors - strings and expressions containing String, Math, Date/Time or FME Feature Functions will have those functions evaluated. Therefore, the names of these functions (in the form @<function_name>) should not be used as literal string values.

Content Types

String Functions	These functions manipulate and format strings.
Special Characters	A set of control characters is available in the Text Editor.
Math Functions	Math functions are available in both editors.
Date/Time Functions	Date and time functions are available in the Text Editor.
Math Operators	These operators are available in the Arithmetic Editor.
FME Feature Functions	These return primarily feature-specific values.
FME Parameters	FME and workspace-specific parameters may be used.
Creating and Modifying User Parameters	Create your own editable parameters.

Dialog Options - Tables

Table Tools

Transformers with table-style parameters have additional tools for populating and manipulating values.

Row Reordering

Enabled once you have clicked on a row item. Choices include:

Add a row
Remove a row
Move current row up one
Move current row down one
Move current row to top
Move current row to bottom

Cut, Copy, and Paste

Enabled once you have clicked on a row item. Choices include:

Cut a row - delete and copy to clipboard
Copy a row to the clipboard
Paste a row from the clipboard

Cut, copy, and paste may be used within a transformer, or between transformers.

Filter

Start typing a string, and the matrix will only display rows matching those characters. Searches all columns. This only affects the display of attributes within the transformer - it does not alter which attributes are output.

Import

Import populates the table with a set of new attributes read from a dataset. Specific application varies between transformers.

Reset/Refresh

Generally resets the table to its initial state, and may provide additional options to remove invalid entries. Behavior varies between transformers.

Note: Not all tools are available in all transformers.

Processing Behavior	Feature-Based
Feature Holding	No
Dependencies
Aliases
History	Released FME 2019.0

RabbitMQConnector

Typical Uses

Configuration

Input Ports

Output Ports

Parameters

Editing Transformer Parameters

Reference

FME Community