amqp — archive

[Rob Godfrey]

All, After discussions with Gordon I’ve updated the naming of the legacy AMQP filter bindings, and also added in logical "or", "and" and "not" filters as in order to replicate the functionality of multiple bindings to the same queue in AMQP v0.x these are also required. At Andreas' request I’ve also updated his JMS filter definitions and included them as Apache sourced definitions. The XML is pasted below, but for convenience you can also find it here: http://people.apache.org/~rgodfrey/amqp-1.0/apache-filters.xml Along with PDF and HTML versions: http://people.apache.org/~rgodfrey/amqp-1.0/apache-filters.pdf http://people.apache.org/~rgodfrey/amqp-1.0/apache-filters.html All comments welcome, Rob =========================== apache-filters.xml =========================== <!-- Licensed to the Apache Software Foundation (ASF) under one or more contributor license agreements. See the NOTICE file distributed with this work for additional information regarding copyright ownership. The ASF licenses this file to you under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at http://www.apache.org/licenses/LICENSE-2.0 Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License. --> <!DOCTYPE amqp SYSTEM "amqp.dtd"> <?xml-stylesheet type="text/xsl" href="amqp.xsl"?> <amqp name="apache-filters" label="Apache Proposed AMQP 1-0 Filters"> <section name="legacy-amqp" title="Legacy AMQP Exchange Binding Support"> <doc> <p> Versions of AMQP prior to 1.0 prescribed a model of Exchanges and Queues, where Queues were bound to Exchanges with a binding key whose meaning depended upon the type of the Exchange. In order to allow a consistent mechanism for addressing legacy AMQP Exchanges over AMQP 1.0 the following filter types are defined. Use of an Exchange as an address for a Source thus can be seen as equivalent to constructing exclusive queues bound to an Exchange in legacy AMQP versions. </p> <p> Containers which support the filters that are defined in this section should advertise the capability <term>APACHE.ORG:LEGACY_AMQP_EXCHANGE_FILTERS</term> in their connection capabilities when sending the open performative, and MUST provide this capability on sources supporting these filter types. </p> </doc> <type class="restricted" name="legacy-amqp-direct-binding" source="string" provides="filter"> <descriptor name="apache.org:legacy-amqp-direct-binding:string" code="0x0000468C:0x00000000"/> <doc> <p> The legacy-amqp-direct-binding filter consists of a described string value. The filter matches a message if and only if the described string value exactly matches the subject field of the Properties section of the message being evaluated. If the message has no Properties section, or if the subject field of the Properties section is not set, then the legacy-amqp-direct-binding filter does not match. </p> </doc> </type> <type class="restricted" name="legacy-amqp-topic-binding" source="string" provides="filter"> <descriptor name="apache.org:legacy-amqp-topic-binding:string" code="0x0000468C:0x00000001"/> <doc> <p> The legacy-amqp-topic-binding filter consists of a described string value. The value value described by the type is interpreted as a pattern to match against the subject field of the Properties section of the message being evaluated. </p> <ul> <li>The pattern is formed using zero or more tokens, with each token delimited by the "." character. The tokens "#" and "*" have special meanings.</li> <li>The token consisting of the single character "*" matches a single word in the subject field.</li> <li>The token consisting of the single character "#" matches zero or more words in the subject field.</li> </ul> <p> Thus the filter value "*.stock.#" would match the subjects "usd.stock" and "eur.stock.db" but not "stock.nasdaq". </p> <p> If the message has no Properties section, or if the subject field of the Properties section is not set, then the legacy-amqp-topic-binding filter matches only if the value of the filter is a single "#". </p> </doc> </type> <type class="restricted" name="legacy-amqp-headers-binding" source="map" provides="filter"> <descriptor name="apache.org:legacy-amqp-headers-binding:map" code="0x0000468C:0x00000002"/> <doc> <p> The legacy-amqp-headers-binding filter consists of a described map value. The map value described by the type is interpreted as a pattern to match against the application-properties section of the message being evaluated. The map has the same restriction as the application-properties section, namely that the keys of this 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. </p> <p> The key "x-match" in the described map has special meaning. This key MUST map to the symbolic value "any" or the symbolic value "all" within the described map. All other keys which begin "x-" MUST be ignored by the source when evaluating. If the value for "x-match" is "all" then all other valid key-value pairs in the map MUST match with an entry with the same key in the application-properties section. If the value for "x-match" is "any" then the filter will accept the message if at least one key-value pair matches the equivalent key value pair in the application-properties section. </p> <p> A key-value pair in the filter's map matches a key-value pair in the application-properties section if the keys are identical (including the same type), or if the value in the filter map for the key is null. </p> </doc> </type> </section> <section name="jms" title="Java Message Service Support"> <doc> <p> The Java Message Service defines two types of filtering of messages: firstly the ability to exclude from a subscription messages sent by the same connection, secondly a more general filtering syntax known as "selectors" based on an SQL like syntax. </p> <p> Containers which support the filters that are defined in this section should advertise the capability <term>APACHE.ORG:JMS_FILTERS</term> in their connection capabilities when sending the open performative, and MUST provide this capability on sources supporting these filter types. </p> </doc> <type class="composite" name="jms-no-local-filter" source="list" provides="filter"> <descriptor name="apache.org:jms-no-local-filter:list" code="0x0000468C:0x00000003"/> <doc> <p> A message will be accepted by the jms-no-local-filter if and only if the message was originally sent to the container of the source on a separate connection from that which is currently receiving from the source. </p> </doc> </type> <type class="restricted" name="jms-selector-filter" provides="filter" source="string"> <descriptor name="apache.org:jms-selector-filter:string" code="0x0000468C:0x00000004"/> <doc> <p> The Java Message Service "selector" defines an SQL like syntax for filtering messages. The selector filters based on the values of "headers" and "properties". The defined JMS headers can be mapped to equivalent fields within the AMQP message sections: </p> <picture title="Mapping JMS Headers to AMQP fields"> JMS Property Name AMQP 1.0 Field ================== ==================================================== JMSCorrelationID correlation-id field of properties section JMSDeliveryMode durable field of header section JMSDestination to field of the properties section JMSExpiration absolute-expiry-time of properties section JMSMessageID message-id of properties section JMSPriority priority field of header section JMSRedelivered delivery-count > 0 in header section JMSReplyTo reply-to in properties section JMSTimestamp creation-time of properties section JMSType annotation jms-type in message-annotations section </picture> <p> The "properties" of the JMS message are equivalent to the AMQP application-properties section. Thus a reference to a property Foo in a message selector would be evaluated as the value associated with the key "Foo" (if present) in the application-properties section. </p> <p> The operands of the JMS selector are defined in terms of the types available within JMS, When evaluated against the application properties section, the values within that section MUST be evaluated according to the following type mapping. </p> <picture title="Mapping AMQP types to JMS types"> AMQP Type JMS Selector Type ================== =================== null null boolean boolean ubyte short ushort int uint long ulong long byte byte short short int int long long float float double double decimal32 double decimal64 double decimal128 double char char timestamp long uuid byte[16] binary byte[] string String symbol String </picture> </doc> </type> </section> <section name="logical" title="Logical Operators"> <doc> <p> The filters field of the source allows for a number of filters to be associated with a source, with a message having to meet the filtering criteria of all filters in order to be passed through. This mechanism allows for a primitive notion of combing filters, but only in logical conjunction. In order to build more complex filters it is useful to allow for a full set of logical combinations. </p> <p> Containers which support the filters that are defined in this section should advertise the capability <term>APACHE.ORG:LOGIC_FILTERS</term> in their connection capabilities when sending the open performative, and MUST provide this capability on sources supporting these filter types. </p> </doc> <type class="restricted" name="or-filter" provides="filter" source="list"> <descriptor name="apache.org:or-filter:list" code="0x0000468C:0x00000005"/> <doc> <p> The or-filter, as its name implies, acts as a logical disjunction of multiple filters. That is the filter accepts a message if at least one of the filters within its list accept the message. </p> </doc> </type> <type class="restricted" name="and-filter" provides="filter" source="list"> <descriptor name="apache.org:and-filter:list" code="0x0000468C:0x00000006"/> <doc> <p> The and-filter, as its name implies, acts as a logical conjunction of multiple filters. That is the filter accepts a message if and only if all of the filters within its list accept the message. </p> </doc> </type> <type class="composite" name="not-filter" provides="filter" source="list"> <descriptor name="apache.org:not-filter:list" code="0x0000468C:0x00000007"/> <doc> <p> The not-filter, as its name implies, acts as a logical negation of the nested filter. That is the filter accepts a message if and only the filter it wraps does not accept the message </p> </doc> <field name="filter" type="*" requires="filter" mandatory="true" label="the filter to be negated"/> </type> </section> </amqp> This email is confidential and subject to important disclaimers and conditions including on offers for the purchase or sale of securities, accuracy and completeness of information, viruses, confidentiality, legal privilege, and legal entity disclaimers, available at http://www.jpmorgan.com/pages/disclosures/email .