bmqa_messageproperties.h File Reference

Provide a VST representing message properties. More...

#include <bmqt_propertytype.h>
#include <bmqt_resultcode.h>
#include <bdlbb_blob.h>
#include <bsl_cstdint.h>
#include <bsl_string.h>
#include <bslma_allocator.h>
#include <bslma_usesbslmaallocator.h>
#include <bslmf_nestedtraitdeclaration.h>
#include <bsls_alignedbuffer.h>
#include <bsls_types.h>

Go to the source code of this file.

Classes
class	BloombergLP::bmqa::MessageProperties
	Provide a VST representing message properties. More...
class	BloombergLP::bmqa::MessagePropertiesIterator

Namespaces
namespace	BloombergLP
namespace	BloombergLP::bmqa

Functions
bsl::ostream &	BloombergLP::bmqa::operator<< (bsl::ostream &stream, const MessageProperties &rhs)

Detailed Description

bmqa::MessageProperties provides a VST representing message properties. Message properties are a collection of name-value pairs that producer can associate with a message, and consumer can retrieve from the corresponding message. In order to keep their usage flexible, no schema is enforced for the message properties, and their format (names and data types) should be negotiated by producers and consumers. Message properties can be used for routing, pipelining or filtering messages within the application. It can be efficient to specify such message attributes in the properties instead of the message payload, because application does not have to decode entire payload to retrieve these attributes. bmqa::MessagePropertiesIterator provides a mechanism to iterate over all the properties of a bmqa::MessageProperties object.

Restrictions on Property Names

• Length of a property name must be greater than zero and must not exceed bmqa::MessageProperties::k_MAX_PROPERTY_NAME_LENGTH.
• First character of the property name must be alpha-numeric.

Restrictions on Property Values

• Length of a property value must be non-negative (ie, can be zero) and must not exceed bmqa::MessageProperties::k_MAX_PROPERTY_VALUE_LENGTH. Note that this restriction is obviously applicable to property values with types bmqt::PropertyType::e_STRING and bmqt::PropertyType::e_BINARY, because for all other property value types, size is implicitly applicable based on the type (see Data Types and Size section in bmqt::PropertyType component).

See also

bmqt::PropertyType