This class provides different utilities related with topics. More...

#include <gz/transport/TopicUtils.hh>

Static Public Member Functions
static std::string	AsValidTopic (const std::string &_topic)
	Convert a topic name to a valid topic. The input topic is modified by:

static std::string	CreateLivelinessToken (const std::string &_fullyQualifiedTopic, const std::string &_pUuid, const std::string &_nUuid, const std::string &_entityType, const std::string &_reqTypeName, const std::string &_repTypeName)
	Create a liveliness token.

static std::string	CreateLivelinessToken (const std::string &_fullyQualifiedTopic, const std::string &_pUuid, const std::string &_nUuid, const std::string &_entityType, const std::string &_typeName)
	Create a liveliness token.

static std::string	CreateLivelinessTokenHelper (const std::string &_fullyQualifiedTopic, const std::string &_pUuid, const std::string &_nUuid, const std::string &_entityType)
	Create a partial liveliness token.

static bool	DecomposeFullyQualifiedTopic (const std::string &_fullyQualifiedName, std::string &_partition, std::string &_namespaceAndTopic)
	Decompose a fully qualified topic name into its partition and topic strings. Note that if the topic is preceded by a namespace, then the namespace and topic name will remain together as one string.

static bool	DecomposeLivelinessToken (const std::string &_token, std::string &_prefix, std::string &_partition, std::string &_namespaceAndTopic, std::string &_pUUID, std::string &_nUUID, std::string &_entityType, std::string &_reqType, std::string &_repType)
	Decompose a Zenoh liveliness token into its components.

static bool	DecomposeLivelinessToken (const std::string &_token, std::string &_prefix, std::string &_partition, std::string &_namespaceAndTopic, std::string &_pUUID, std::string &_nUUID, std::string &_entityType, std::string &_typeName)
	Decompose a Zenoh liveliness token into its components.

static bool	DecomposeLivelinessTokenHelper (const std::string &_token, std::string &_prefix, std::string &_partition, std::string &_namespaceAndTopic, std::string &_pUUID, std::string &_nUUID, std::string &_entityType, std::string &_remainingToken)
	Partially decompose a Zenoh liveliness token into its components.

static std::string	DemangleName (const std::string &_input)
	Recompose a previously mangled name.

static bool	DemangleType (const std::string &_input, std::vector< std::string > &_output)
	Recompose a previously mangled type.

static bool	FullyQualifiedName (const std::string &_partition, const std::string &_ns, const std::string &_topic, std::string &_name)
	Get the full topic path given a namespace and a topic name. A fully qualified topic name's length must not exceed kMaxNameLength. The fully qualified name follows the next syntax: @<PARTITION>@<NAMESPACE>/<TOPIC> where: <PARTITION>: The name of the partition or empty string. A "/" will be prefixed to the partition name unless is empty or it already starts with slash. A trailing slash will always be removed. <NAMESPACE>: The namespace or empty string. A namespace is a prefix applied to the topic name. If not empty, it will always start with a "/". A trailing slash will always be removed <TOPIC>: The topic name. A trailing slash will always be removed.

static bool	IsValidNamespace (const std::string &_ns)
	Determines if a namespace is valid. A namespace's length must not exceed kMaxNameLength. The following symbols are not allowed as part of the namespace: '@', ':=', '~'.

static bool	IsValidPartition (const std::string &_partition)
	Determines if a partition is valid. The same rules to validate a topic name applies to a partition with the addition of the empty string, which is a valid partition (meaning no partition is used). A partition name's length must not exceed kMaxNameLength.

static bool	IsValidTopic (const std::string &_topic)
	Determines if a topic name is valid. A topic name is any non-empty alphanumeric string. The symbol '/' is also allowed as part of a topic name. The following symbols are not allowed as part of the topic name: '@', ':=', '~'. A topic name's length must not exceed kMaxNameLength. Examples of valid topics: abc, /abc, /abc/de, /abc/de/.

static std::string	MangleName (const std::string &_input)
	Replace "/" instances with "%".

static bool	MangleType (const std::vector< std::string > &_input, std::string &_output)
	Mangle multiple types into a single string using "&" as delimiter.

Static Public Attributes
static const uint16_t	kMaxNameLength = 65535
	The kMaxNameLength specifies the maximum number of characters allowed in a namespace, a partition name, a topic name, and a fully qualified topic name.

static const char	kSlashReplacement
	A replacement for the slash when mangling names.

static const char	kTokenPrefix []
	A common prefix for all liveliness tokens.

static const char	kTokenSeparator []
	The separator used within the liveliness token.

static const char	kTypeSeparator []
	The separator used to concatenate type names.

Detailed Description

This class provides different utilities related with topics.

Member Function Documentation

◆ AsValidTopic()

static std::string AsValidTopic ( const std::string & _topic )

static

Convert a topic name to a valid topic. The input topic is modified by:

turning white space into _.
removing special characters and combinations.
Parameters

[in] _topic Input topic, which may be invalid.

Returns
A valid topic, or empty string if not possible to convert.

◆ CreateLivelinessToken() [1/2]

static std::string CreateLivelinessToken	(	const std::string &	_fullyQualifiedTopic,
		const std::string &	_pUuid,
		const std::string &	_nUuid,
		const std::string &	_entityType,
		const std::string &	_reqTypeName,
		const std::string &	_repTypeName
	)

static

Create a liveliness token.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_fullyQualifiedTopic	The fully qualified topic.
[in]	_pUuid	The process UUID.
[in]	_nUuid	The node UUID.
[in]	_entityType	The entity type. MP for a message publisher. MS for a message subscription. SS for a service server.
[in]	_reqTypeName	The service request type.
[in]	_repTypeName	The service response type.

Returns: The liveliness token.

◆ CreateLivelinessToken() [2/2]

static std::string CreateLivelinessToken	(	const std::string &	_fullyQualifiedTopic,
		const std::string &	_pUuid,
		const std::string &	_nUuid,
		const std::string &	_entityType,
		const std::string &	_typeName
	)

static

Create a liveliness token.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_fullyQualifiedTopic	The fully qualified topic.
[in]	_pUuid	The process UUID.
[in]	_nUuid	The node UUID.
[in]	_entityType	The entity type. MP for a message publisher. MS for a message subscription. SS for a service server.
[in]	_typeName	The message type.

Returns: The liveliness token.

◆ CreateLivelinessTokenHelper()

static std::string CreateLivelinessTokenHelper	(	const std::string &	_fullyQualifiedTopic,
		const std::string &	_pUuid,
		const std::string &	_nUuid,
		const std::string &	_entityType
	)

static

Create a partial liveliness token.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_fullyQualifiedTopic	The fully qualified topic.
[in]	_pUuid	The process UUID.
[in]	_nUuid	The node UUID.
[in]	_entityType	The entity type. MP for a message publisher. MS for a message subscription. SS for a service server.

Returns: A partial liveliness token.

◆ DecomposeFullyQualifiedTopic()

static bool DecomposeFullyQualifiedTopic	(	const std::string &	_fullyQualifiedName,
		std::string &	_partition,
		std::string &	_namespaceAndTopic
	)

static

Decompose a fully qualified topic name into its partition and topic strings. Note that if the topic is preceded by a namespace, then the namespace and topic name will remain together as one string.

Given a fully qualified topic name with the following syntax:

@<PARTITION>@<NAMESPACE>/<TOPIC>

The _partition output argument will be set to <PARTITION>, and the _namespaceAndTopic output argument will be set to <NAMESPACE>/<TOPIC>.

Parameters

[in]	_fullyQualifiedName	The fully qualified topic name.
[out]	_partition	The partition component of the fully qualified topic name.
[out]	_namespaceAndTopic	The namespace and topic name component. Note that there is no way to distinguish between where a namespace ends and a topic name begins, since topic names may contain slashes.

Returns: True if the topic and partition were set.

See also: FullyQualifiedName

◆ DecomposeLivelinessToken() [1/2]

static bool DecomposeLivelinessToken	(	const std::string &	_token,
		std::string &	_prefix,
		std::string &	_partition,
		std::string &	_namespaceAndTopic,
		std::string &	_pUUID,
		std::string &	_nUUID,
		std::string &	_entityType,
		std::string &	_reqType,
		std::string &	_repType
	)

static

Decompose a Zenoh liveliness token into its components.

Given a Zenoh liveliness token with the following syntax:

The _prefix output argument will be set from <prefix>, the _partition output argument will be set from <partition>, the _namespaceAndTopic output argument will be set and unmangled from <mangled_namespace>/<mangled_qualified_name>, the _pUUID output argument will be set from <session_id>, the _nUUID output argument will be set from <node_id>, the _entityType output argument will be set from <entity_kind>, the _reqType and _reptype output arguments will be set from unmangling <type_name>.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_token	The Zenoh liveliness token.
[out]	_prefix	The prefix component.
[out]	_partition	The partition component.
[out]	_namespaceAndTopic	The namespace and topic name component. Note that there is no way to distinguish between where a namespace ends and a topic name begins, since topic names may contain slashes.
[out]	_pUUID	The process UUID component.
[out]	_nUUID	The node UUID component.
[out]	_entityType	The entity type. MP for a message publisher. MS for a message subscription. SS for a service server.
[out]	_reqType	The service request message type.
[out]	_repType	The service response message type.

Returns: True if all the components were set.

◆ DecomposeLivelinessToken() [2/2]

static bool DecomposeLivelinessToken	(	const std::string &	_token,
		std::string &	_prefix,
		std::string &	_partition,
		std::string &	_namespaceAndTopic,
		std::string &	_pUUID,
		std::string &	_nUUID,
		std::string &	_entityType,
		std::string &	_typeName
	)

static

Decompose a Zenoh liveliness token into its components.

Given a Zenoh liveliness token with the following syntax:

The _prefix output argument will be set from <prefix>, the _partition output argument will be set from <partition>, the _namespaceAndTopic output argument will be set and unmangled from <mangled_namespace>/<mangled_qualified_name>, the _pUUID output argument will be set from <session_id>, the _nUUID output argument will be set from <node_id>, the _entityType output argument will be set from <entity_kind>, the _msgType output argument will be set from <type_name>.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_token	The Zenoh liveliness token.
[out]	_prefix	The prefix component.
[out]	_partition	The partition component.
[out]	_namespaceAndTopic	The namespace and topic name component. Note that there is no way to distinguish between where a namespace ends and a topic name begins, since topic names may contain slashes.
[out]	_pUUID	The process UUID component.
[out]	_nUUID	The node UUID component.
[out]	_entityType	The entity type. MP for a message publisher. MS for a message subscription. SS for a service server.
[out]	_typeName	The message type component.

Returns: True if all the components were set.

◆ DecomposeLivelinessTokenHelper()

static bool DecomposeLivelinessTokenHelper	(	const std::string &	_token,
		std::string &	_prefix,
		std::string &	_partition,
		std::string &	_namespaceAndTopic,
		std::string &	_pUUID,
		std::string &	_nUUID,
		std::string &	_entityType,
		std::string &	_remainingToken
	)

static

Partially decompose a Zenoh liveliness token into its components.

Given a Zenoh liveliness token with the following syntax:

The _prefix output argument will be set from <prefix>, the _partition output argument will be set from <partition>, the _namespaceAndTopic output argument will be set and unmangled from <mangled_namespace>/<mangled_qualified_name>, the _pUUID output argument will be set from <session_id>, the _nUUID output argument will be set from <node_id>, the _entityType output argument will be set from <entity_kind>, the _remainingToken output argument will be set from the remaining token to be processed afterwards.

We're using the ROS 2 liveliness token convention. https://github.com/ros2/rmw_zenoh/blob/rolling/docs/design.md#graph-cache

Parameters

[in]	_token	The Zenoh liveliness token.
[out]	_prefix	The prefix component.
[out]	_partition	The partition component.
[out]	_namespaceAndTopic	The namespace and topic name component. Note that there is no way to distinguish between where a namespace ends and a topic name begins, since topic names may contain slashes.
[out]	_pUUID	The process UUID component.
[out]	_nUUID	The node UUID component.
[out]	_entityType	The entity type (pub, sub) component.
[out]	_remainingToken	The part of the token unprocessed.

Returns: True if all the components were set.

◆ DemangleName()

static std::string DemangleName ( const std::string & _input )

static

Recompose a previously mangled name.

Parameters

[in] _input Input mangled name.

Returns: The unmangled name.

◆ DemangleType()

static bool DemangleType	(	const std::string &	_input,
		std::vector< std::string > &	_output
	)

static

Recompose a previously mangled type.

Parameters

[in]	_input	Input mangled type.
[out]	_output	The unmangled vector with types.

Returns: True if the demanged worked succesfully.

◆ FullyQualifiedName()

static bool FullyQualifiedName	(	const std::string &	_partition,
		const std::string &	_ns,
		const std::string &	_topic,
		std::string &	_name
	)

static

Get the full topic path given a namespace and a topic name. A fully qualified topic name's length must not exceed kMaxNameLength. The fully qualified name follows the next syntax: @<PARTITION>@<NAMESPACE>/<TOPIC> where: <PARTITION>: The name of the partition or empty string. A "/" will be prefixed to the partition name unless is empty or it already starts with slash. A trailing slash will always be removed. <NAMESPACE>: The namespace or empty string. A namespace is a prefix applied to the topic name. If not empty, it will always start with a "/". A trailing slash will always be removed <TOPIC>: The topic name. A trailing slash will always be removed.

Note: Intuitively, you can imagine the fully qualified name as a UNIX absolute path, where the partition is always surrounded by "@". A namespace, if present, corresponds with the directories of the path, and you can imagine the topic as the filename.

E.g.: Only topic: @/topic No partition: @/namespace/topic1 No namespace: @/partition@/topic1 Partition+namespace+topic: @/my_partition@/name/space/topic

Parameters

[in]	_partition	Partition name.
[in]	_ns	Namespace.
[in]	_topic	Topic name.
[out]	_name	Fully qualified topic name.

Returns: True if the fully qualified name is valid (if partition, namespace and topic are correct).

See also: IsValidPartition; IsValidNamespace; IsValidTopic; DecomposeFullyQualifiedTopic

Referenced by FullyQualifiedTopic::FullyQualifiedTopic().

◆ IsValidNamespace()

static bool IsValidNamespace ( const std::string & _ns )

static

Determines if a namespace is valid. A namespace's length must not exceed kMaxNameLength. The following symbols are not allowed as part of the namespace: '@', ':=', '~'.

Parameters

[in] _ns Namespace to be checked.

Returns: true if the namespace is valid.

◆ IsValidPartition()

static bool IsValidPartition ( const std::string & _partition )

static

Determines if a partition is valid. The same rules to validate a topic name applies to a partition with the addition of the empty string, which is a valid partition (meaning no partition is used). A partition name's length must not exceed kMaxNameLength.

Parameters

[in] _partition Partition to be checked.

Returns: true if the partition is valid.

◆ IsValidTopic()

static bool IsValidTopic ( const std::string & _topic )

static

Determines if a topic name is valid. A topic name is any non-empty alphanumeric string. The symbol '/' is also allowed as part of a topic name. The following symbols are not allowed as part of the topic name: '@', ':=', '~'. A topic name's length must not exceed kMaxNameLength. Examples of valid topics: abc, /abc, /abc/de, /abc/de/.

Parameters

[in] _topic Topic name to be checked.

Returns: true if the topic name is valid.

◆ MangleName()

static std::string MangleName ( const std::string & _input )

static

Replace "/" instances with "%".

Parameters

[in] _input Input name.

Returns: The mangled name.

◆ MangleType()

static bool MangleType	(	const std::vector< std::string > &	_input,
		std::string &	_output
	)

static

Mangle multiple types into a single string using "&" as delimiter.

Parameters

[in]	_input	Input vector with types.
[out]	_output	The mangled string.

Returns: True if the mangled worked succesfully.

Member Data Documentation

◆ kMaxNameLength

const uint16_t kMaxNameLength = 65535

static

The kMaxNameLength specifies the maximum number of characters allowed in a namespace, a partition name, a topic name, and a fully qualified topic name.

◆ kSlashReplacement

const char kSlashReplacement

static

A replacement for the slash when mangling names.

◆ kTokenPrefix

const char kTokenPrefix[]

static

A common prefix for all liveliness tokens.

◆ kTokenSeparator

const char kTokenSeparator[]

static

The separator used within the liveliness token.

◆ kTypeSeparator

const char kTypeSeparator[]

static

The separator used to concatenate type names.

The documentation for this class was generated from the following file:

TopicUtils.hh

Gazebo Transport

API Reference

Static Public Member Functions

Static Public Attributes

Detailed Description

Member Function Documentation

◆ AsValidTopic()

◆ CreateLivelinessToken() [1/2]

◆ CreateLivelinessToken() [2/2]

◆ CreateLivelinessTokenHelper()

◆ DecomposeFullyQualifiedTopic()

◆ DecomposeLivelinessToken() [1/2]

◆ DecomposeLivelinessToken() [2/2]

◆ DecomposeLivelinessTokenHelper()

◆ DemangleName()

◆ DemangleType()

◆ FullyQualifiedName()

◆ IsValidNamespace()

◆ IsValidPartition()

◆ IsValidTopic()

◆ MangleName()

◆ MangleType()

Member Data Documentation

◆ kMaxNameLength

◆ kSlashReplacement

◆ kTokenPrefix

◆ kTokenSeparator

◆ kTypeSeparator