The Descriptor class provides meta-information about what a log contains. This may be useful for determining QueryOptions or for generating a high-level overview of a Log's contents. More...
#include <Descriptor.hh>
Public Types | |
using | NameToId = std::map< std::string, int64_t > |
A map from a name (e.g. topic name or message type name) to the id of a row in one of the database tables. (name -> id) | |
using | NameToMap = std::map< std::string, NameToId > |
A map from a name to a map from a name to a row ID. (name -> name -> id) | |
Public Member Functions | |
Descriptor (Descriptor &&_orig) | |
Move constructor, not used by most. | |
~Descriptor () | |
Destructor. | |
const NameToMap & | MsgTypesToTopicsToId () const |
A topic in the database is uniquely identified by a pair of (topic name, message type). This function allows you to find the id of a topic by searching (message type name -> topic name -> ID). | |
int64_t | TopicId (const std::string &_topicName, const std::string &_msgType) const |
Convenience method to get an id given a topic name and type. | |
const NameToMap & | TopicsToMsgTypesToId () const |
A topic in the database is uniquely identified by a pair of (topic name, message type). This function allows you to find the id of a topic by searching (topic name -> message type name -> ID). | |
Detailed Description
The Descriptor class provides meta-information about what a log contains. This may be useful for determining QueryOptions or for generating a high-level overview of a Log's contents.
Member Typedef Documentation
◆ NameToId
using NameToId = std::map<std::string, int64_t> |
A map from a name (e.g. topic name or message type name) to the id of a row in one of the database tables. (name -> id)
◆ NameToMap
using NameToMap = std::map<std::string, NameToId> |
A map from a name to a map from a name to a row ID. (name -> name -> id)
Constructor & Destructor Documentation
◆ ~Descriptor()
~Descriptor | ( | ) |
Destructor.
◆ Descriptor()
Descriptor | ( | Descriptor && | _orig | ) |
Move constructor, not used by most.
Member Function Documentation
◆ MsgTypesToTopicsToId()
const NameToMap & MsgTypesToTopicsToId | ( | ) | const |
A topic in the database is uniquely identified by a pair of (topic name, message type). This function allows you to find the id of a topic by searching (message type name -> topic name -> ID).
- Returns
- A map from message types to a map of topic names to row ids.
- See also
- TopicsToMsgTypesToId()
◆ TopicId()
int64_t TopicId | ( | const std::string & | _topicName, |
const std::string & | _msgType | ||
) | const |
Convenience method to get an id given a topic name and type.
- Parameters
-
[in] _topicName Name of the topic that you are interested in. [in] _msgType Name of the message type that you are interested in.
- Returns
- an id of a row in the topics table, or -1 none exists
◆ TopicsToMsgTypesToId()
const NameToMap & TopicsToMsgTypesToId | ( | ) | const |
A topic in the database is uniquely identified by a pair of (topic name, message type). This function allows you to find the id of a topic by searching (topic name -> message type name -> ID).
- Returns
- A map from topic names to a map of message types to row ids.
- See also
- MsgTypesToTopicsToId()
The documentation for this class was generated from the following file: