Universal Messaging 10.7 | Concepts | AMQP | AMQP Guide | AMQP Messages
 
AMQP Messages
AMQP Types
AMQP defines a set of commonly used primitive types aimed towards a cross-platform interoperable data representation
These primitive types are divided into the following categories:
*Primitive
*Described
*Composite
*Restricted
NOTE: In Universal Messaging, an embedded Apache Qpid Proton-J protocol engine is used for type marshalling so all type mappings occur as defined by the Proton-J API. See the Qpid Proton page at https://qpid.apache.org/proton/index.html for details.
AMQP Message Format
AMQP offers a standard message format (default) which can be overridden by an AMQP node. It consists of a bare message (immutable end-end) and an annotated message which may be altered by peer / intermediate nodes.
The following figure illustrates the default AMQP message format:
NOTE: Universal Messaging supports the default message format and provides a transformation layer based on it. Currently no tests have been performed with a custom AMQP message format, at the very least transformers would fail.
Transfer Headers
AMQP header
UM Header
AMQP Type
Java Type
UM 10.7
durable
nPublished.isPersistent
boolean
boolean
(tick)
priority
nHeader.Priority
ubyte (Default: 4)
byte
(tick)
ttl
nHeader.TTL
milliseconds (uint)
long
(tick)
first-acquirer
nEventProperties.JMS_AMQP_FirstAcquirer
boolean
boolean
(tick)
delivery-count
nHeader.RedeliveredCount
uint (Default: 0)
long
(tick)
Note:
Transfer headers are always mapped irrespective of whether an AMQP transformer is used or not.
Delivery Annotations
AMQP Delivery annotations offer an optional non-normative section for AMQP vendor defined recipients by typically providing delivery related information from the sending node to the receiving node.
AMQP Delivery Annotation
UM Header Key
AMQP Key/Value Type
Java Key/Value Type
UM 10.7
SomeDeliveryAnnotation
JMS_AMQP_DA_<AMQP_SYMBOL_NAME(SomeDeliveryAnnotation)>
AMQP Symbol / AMQP Value
String / nEventProperties Value
(tick)
Universal Messaging currently does not make use of any delivery annotations but will preserve any received. The naming convention used is <JMS_AMQP_DA_><delivery annotation symbol>
Message Annotations
AMQP Message annotations offer an optional section for AMQP properties aimed at AMQP infrastructure nodes. The following table illustrates the mappings to Universal Messaging:
AMQP Message Annotation
UM Header Key
AMQP Key/Value Type
Java Key/Value Type
UM 10.7
SomeMessageAnnotation
JMS_AMQP_MA_<AMQP SYMBOL_NAME(SomeMessageAnnotation)>
AMQP Symbol / AMQP Value
String / nEventProperties Value
x-opt-jms-msg-type
JMS_AMQP_MA_x-opt-jms-msg-type
x-opt-jms-msg-type / AMQP byte
String / byte (nHeader.MessageType)
(tick)
x-opt-jms-dest
JMS_AMQP_MA_x-opt-jms-dest
x-opt-jms-dest / AMQP String
String / byte[] (nHeader.Type)
(tick)
x-opt-reply-type
JMS_AMQP_MA_x-opt-reply-type
x-opt-reply-type / AMQP byte
String / byte (nHeader.ReplyType)
(tick)
Note:
Only applies when using the Complete AMQP Transformer.
Standard Message Properties
AMQP standard message properties is a section used for a defined set of immutable standard properties of the message. The section is part of the bare message; therefore, if retransmitted by an intermediary, it must remain unaltered.
The following table illustrates how these standard message properties are mapped to Universal Messaging:
AMQP Standard Property
UM Header Mapping
AMQP Type
Java Value Type
UM 10.7
message-id
nHeader.MessageId
AMQP String
byte[]
(tick)
user-id
nHeader.UserId
AMQP Binary
byte[]
(tick)
to
nHeader.Destination
AMQP String
byte[]
(tick)
subject
nEventProperties.JMS_AMQP_SUBJECT
AMQP String
String
(tick)
reply-to
nHeader.ReplyToName
AMQP String
byte[]
(tick)
correlation-id
nHeader.CorrelationId
AMQP Value
byte[]
(tick)
content-type
nEventProperties.JMS_AMQP_CONTENT_TYPE
AMQP Symbol
String
(tick)
content-encoding
nEventProperties.JMS_AMQP_CONTENT_ENCODING
AMQP Symbol
String
(tick)
absolute-expiry-time
N/A (Currently unsupported)
AMQP Date
long
(error)
creation-time
nHeader.Timestamp
AMQP Date
long
(tick)
group-id
nEventProperties.JMSXGroupID
AMQP String
String
(tick)
group-sequence
nEventProperties.JMS_AMQP_GROUP_SEQUENCE
AMQP uint
int
(tick)
reply-to-group-id
nEventPropties.JMS_AMQP_ReplyToGroupID
AMQP String
String
(tick)
Note:
Only applies when using the Complete AMQP Transformer.
Application Message Properties
AMQP offers an optional application-properties section, part of the bare message used for structured application data. Intermediaries can use the data within this structure for the purposes of filtering or routing.
The keys of this map are restricted to be of type string (which excludes the possibility of a null key) and the values are restricted to be of simple types only, that is, excluding map, list, and array types. The following table illustrates how these are mapped to Universal Messaging:
AMQP Application Message Properties
UM Dictionary Key
AMQP Key/Value Type
Java Key/Value Type
UM 10.7
MAP < STRING, SIMPLE VALUE >
AMQP String / AMQP Value
String / nEventProperties Value
(tick)
example_application_key1
example_application_key1
AMQP String / AMQP Value
String / nEventProperties Value
(tick)
Note:
In Universal Messaging the nEventProperties and nHeader objects are mapped to a few AMQP message format sections. Therefore there will be property keys mappable to different sections stored in the same structure, implying that this section refers to all keys that do not fall in the other sections.
Message Body
AMQP message body is defined in 3 possible ways:
*One or more AMQP Data sections
*One or more AMQP Sequence sections
*A single AMQP Value section
Universal Messaging currently aims to offer support for JMS 1.1 use cases via AMQP and therefore has implemented some mappings via the Complete AMQP transformer.
The mappings are based on the following UM constants:
UM nHeader.MessageType
UM Dictionary Key (transformed)
Value (byte)
UM 10.7
JMS_BASE_MESSAGE_TYPE
AMQP_Type
0
(tick)
JMS_MAP_MESSAGE_TYPE
AMQP_Type
1
(tick)
JMS_BYTES_MESSAGE_TYPE
AMQP_Type
2
(tick)
JMS_OBJECT_MESSAGE_TYPE
AMQP_Type
3
(tick)
JMS_STREAM_MESSAGE_TYPE
AMQP_Type
4
(tick)
JMS_TEXT_MESSAGE_TYPE
AMQP_Type
5
(tick)
Universal Messaging extended message types, such as protobuf, are not supported by the transformation framework.
Additionally, mappings (depending on the direction) are based on the following UM AMQP Transformation constants:
UM AMQP Transformation Constant
UM Dictionary Key (transformed)
Value (int)
UM 10.7
sAMQPData
AMQP_Type
0
(tick)
sAMQPValue
AMQP_Type
1
(tick)
sAMQPList
AMQP_Type
2
(tick)
sAMQPEmpty
AMQP_Type
3
(tick)
sAMQPUnknown
AMQP_Type
-1
(tick)
Message Body: AMQP payloads to UM Native payloads
Initially, the Universal Messaging realm will check for an AMQP message annotation x-opt-jms-msg-type on the AMQP message. If detected and within the range of the above mentioned table, then the following conversions are performed:
x-opt-jms-msg-type Message Annotation
AMQP Body
UM Stamping
UM payload
UM 10.7
JMS_BASE_MESSAGE_TYPE
Any
AMQP_Type=sAMQPEmpty
byte[0]
(tick)
JMS_BYTES_MESSAGE_TYPE
null
byte[0]
(tick)
JMS_BYTES_MESSAGE_TYPE
Data
AMQP_Type=sAMQPData
Binary.Array
(tick)
JMS_BYTES_MESSAGE_TYPE
AMQP Value <Binary>
AMQP_Type=sAMQPValue
Binary.Array
(tick)
JMS_TEXT_MESSAGE_TYPE
null
byte[0]
(tick)
JMS_TEXT_MESSAGE_TYPE
Data
AMQP_Type=sAMQPData
Binary.Array (UTF-8)
(tick)
JMS_TEXT_MESSAGE_TYPE
AMQP Value <Binary>
AMQP_Type=sAMQPValue
Binary.Array (UTF-8)
(tick)
JMS_OBJECT_MESSAGE_TYPE
null
AMQP_Type=sAMQPData
byte[0]
(tick)
JMS_OBJECT_MESSAGE_TYPE
Data
AMQP_Type=sAMQPData
Binary.Array
(tick)
JMS_STREAM_MESSAGE_TYPE
null
byte[0]
(tick)
JMS_STREAM_MESSAGE_TYPE
AMQP Value <List>
AMQP_Type=sAMQPValue
byte[](Serialized Vector<Binary>)
(tick)
JMS_STREAM_MESSAGE_TYPE
AMQP Sequence
AMQP_Type=sAMQPList
byte[](Serialized Vector<Binary>)
(tick)
JMS_MAP_MESSAGE_TYPE
null
byte[0]
(tick)
JMS_MAP_MESSAGE_TYPE
AMQP Value <Map>
AMQP_Type=sAMQPValue
byte[](Externalized fEventDictionary)
(tick)
Note:
Only applies when using the Complete AMQP Transformer
If the message annotation is not present, then the mapping starts looking for payload hints in message properties as follows:
AMQP Message Property
AMQP Body
UM nHeader.MessageType
UM payload
UM 10.7
content-type
text/plain
null
JMS_TEXT_MESSAGE_TYPE
byte[0]
(tick)
application/x-java-serialized-object
null
JMS_OBJECT_MESSAGE_TYPE
byte[0]
(tick)
application/octet-stream
null
JMS_BYTES_MESSAGE_TYPE
byte[0]
(tick)
null or other
null
JMS_BASE_MESSAGE_TYPE
byte[0]
(tick)
text/plain
Data
JMS_TEXT_MESSAGE_TYPE
Binary.Array(UTF-8)
(tick)
application/x-java-serialized-object
Data
JMS_OBJECT_MESSAGE_TYPE
Binary.Array
(tick)
application/octet-stream or null
Data
JMS_BYTES_MESSAGE_TYPE
Binary.Array
(tick)
other
Data
JMS_BYTES_MESSAGE_TYPE
Binary.Array
(tick)
AMQP Value <Type> body
null
AMQP Value <null>
JMS_BASE_MESSAGE_TYPE
byte[0]
(tick)
String
AMQP Value <String>
JMS_TEXT_MESSAGE_TYPE
Binary.Array (UTF-8)
(tick)
Binary
AMQP Value <Binary>
JMS_BYTES_MESSAGE_TYPE
Binary.Array
(tick)
List
AMQP Value <List>
JMS_STREAM_MESSAGE_TYPE
byte[](Serialized Vector<Binary>)
(tick)
Map
AMQP Value <Map>
JMS_MAP_MESSAGE_TYPE
byte[](Externalized fEventDictionary)
(tick)
other
AMQP Value <Object>
JMS_OBJECT_MESSAGE_TYPE
Binary.Array
(tick)
AMQP Sequence <Object> body
Binary
AMQP Sequence<Binary>
JMS_OBJECT_MESSAGE_TYPE
Binary.Array
(tick)
Note:
Only applies when using the Complete AMQP Transformer.
Message Body: UM Native Payloads to AMQP payloads
Initially, the Universal Messaging realm will check for an nEventProperties keys called AMQP_Type which is expected to be within the range defined by the AMQP Transformation Constants table. Typically these are AMQP messages previously transformed to native but as there are multiple possibilities with regard to the type of payload this should be transformed to, this value gives us a hint. If not present, it defaults to sAMQPUnknown.
Based on the UM nHeader.MessageType values the following conversions are performed:
UM nHeader.MessageType
UM Dictionary Key AMQP_Type
AMQP Payload
UM 10.7
JMS_BASE_MESSAGE_TYPE
sAMQPEmpty or sAMQPUnknown or sAMQPData
Data(byte[0])
(tick)
JMS_BASE_MESSAGE_TYPE
sAMQPValue
AMQPValue(null)
(tick)
JMS_BASE_MESSAGE_TYPE
sAMQPList
(error)
JMS_MAP_MESSAGE_TYPE
sAMQPEmpty
Data(byte[0])
(tick)
JMS_MAP_MESSAGE_TYPE
sAMQPValue or sAMQPUnknown
AMQPValue<Map> (from byte[](Externalized fEventDictionary)
(tick)
JMS_MAP_MESSAGE_TYPE
sAMQPList or sAMQPData
(error)
JMS_BYTES_MESSAGE_TYPE
sAMQPEmpty
Data(byte[0])
(tick)
JMS_BYTES_MESSAGE_TYPE
sAMQPData orsAMQPUnknown
Data(Binary(byte[])) (from UM native payload)
(tick)
JMS_BYTES_MESSAGE_TYPE
sAMQPValue
AMQPValue(Binary(byte[])) (from UM native payload)
(tick)
JMS_BYTES_MESSAGE_TYPE
sAMQPList
(error)
JMS_OBJECT_MESSAGE_TYPE
sAMQPEmpty
Data(byte[0])
(tick)
JMS_OBJECT_MESSAGE_TYPE
sAMQPData orsAMQPUnknown
Data(Binary(byte[])) (from UM native payload)
(tick)
JMS_OBJECT_MESSAGE_TYPE
sAMQPList or sAMQPValue
(error)
JMS_STREAM_MESSAGE_TYPE
sAMQPEmpty
Data(byte[0])
(tick)
JMS_STREAM_MESSAGE_TYPE
sAMQPList
AMQPSequence<Vector> (byte[](Serialized Vector<Binary>)
(tick)
JMS_STREAM_MESSAGE_TYPE
sAMQPValue or sAMQPUnknown
AMQPValue<Vector> (byte[](Serialized Vector<Binary>)
(tick)
JMS_STREAM_MESSAGE_TYPE
sAMQPData
(error)
JMS_TEXT_MESSAGE_TYPE
sAMQPEmpty
Data(byte[0])
(tick)
JMS_TEXT_MESSAGE_TYPE
sAMQPData
Data(Binary(byte[])) (from UM native payload)
(tick)
JMS_TEXT_MESSAGE_TYPE
sAMQPValue orsAMQPUnknown
AMQPValue<String> (from UM native payload)
(tick)
JMS_TEXT_MESSAGE_TYPE
sAMQPList
(error)
Note:
Only applies when using the Complete AMQP Transformer.
Message Footer
AMQP Message footer offers an optional non-normative section for delivery or message metadata that can be calculated / validated only after the whole message has been processed (e.g digital signature verification, encryption etc).
The following table shows how these are mapped in Universal Messaging:
AMQP Message Footer
UM Sub Dictionary Key
AMQP Key/Value Type
Java Key/Value Type
UM 10.7
MAP < SYMBOL, VALUE >
Footer
AMQP Symbol / AMQP Value
String / nEventProperties Value
(tick)
example_footer_key1
Footer.example_footer_key1
AMQP Symbol / AMQP Value
String / nEventProperties Value
(tick)
Note:
Only applies when using the Complete AMQP Transformer.