ProtoLogger Class Reference

#include <proto_logger.h>

Public Member Functions
	ProtoLogger (const std::string &log_path, std::function< double()> time_provider, bool friendly_colour_yellow)
	ProtoLogger (const ProtoLogger &)=delete
ProtoLogger &	operator= (const ProtoLogger &)=delete
void	saveSerializedProto (const std::string &protobuf_type_full_name, const std::string &serialized_proto)
template<typename ProtoType >
void	saveSerializedProto (const std::string &serialized_proto)
void	updateTimeProvider (std::function< double()> time_provider)
void	flushAndStopLogging ()

Static Public Member Functions
static std::string	createLogEntry (const std::string &proto_full_name, const std::string &serialized_proto, double receive_time_sec)

Detailed Description

Logs incoming Protobufs to a folder to be played back later.

Each entry will contain:

• The timestamp
• The protobuf type
• The protobuf serialized as base64 (to remove newline characters)

Stored in log_path/proto_YYYY_MM_DD_HH_MM_SS/ With each entry in the file formatted as timestamp,protobuf_type,protobuf_base64 Note that in order to reduce the size of the log files, the files are compressed using gzip.

We need to store the data in a way that we can:

1. Replay the data chronologically
2. Seek to a specific time (random access)

To seek to a specific time, we need to load the entire log file into memory. To make this feasible, we store the data in chunks. Each chunk contains REPLAY_MAX_CHUNK_SIZE_BYTES of serialized protos. We can load each chunk into memory and perform search operations to find the appropriate entry. Or we can just play the chunks in order.

Constructor & Destructor Documentation

ProtoLogger() [1/2]

ProtoLogger ( const std::string &  log_path, std::function< double()>  time_provider, bool  friendly_colour_yellow  )

explicit

Constructor

Parameters

log_path	The path to the directory where the logs will be saved
time_provider	A function that returns the current time in seconds
friendly_colour_yellow	Whether the friendly team is yellow or not

ProtoLogger() [2/2]

ProtoLogger ( const ProtoLogger &  )

delete

Removing copy constructor and assignment operator to prevent accidental copying of the ProtoLogger.

Member Function Documentation

createLogEntry()

std::string createLogEntry ( const std::string &  proto_full_name, const std::string &  serialized_proto, double  receive_time_sec  )

static

Helper function for creating a log entry

Parameters

protobuf_type_full_name	The full name of the protobuf message type (e.g. TbotsProto.ThunderbotsConfig)
serialized_proto	The serialized protobuf message to store
receive_time_sec	The time the protobuf was received

Returns

A string containing the log entry

flushAndStopLogging()

void flushAndStopLogging

(

)

Flushes the buffer and stops the logging thread.

Note

ProtoLogger will try to flush the buffer for up to MAX_TIME_TO_EXIT_FULL_SYSTEM_SEC seconds before stopping the logging thread. As such, if there are many logs in the buffer, not all may be flushed in time and some data may be lost.

saveSerializedProto() [1/2]

void saveSerializedProto	(	const std::string &	protobuf_type_full_name,
		const std::string &	serialized_proto
	)

Saves a serialized protobuf message to the log

Parameters

protobuf_type_full_name	The full name of the protobuf message type (e.g. TbotsProto.ThunderbotsConfig)
serialized_proto	The serialized protobuf message to store

saveSerializedProto() [2/2]

template<typename ProtoType >

void saveSerializedProto ( const std::string &  serialized_proto )

inline

Saves a serialized protobuf message to the log

Template Parameters

ProtoType

The type of the protobuf message (Must extend the google::protobuf::Message class and not google::protobuf::MessageLite so it has reflection capabilities)

Parameters

serialized_proto

The serialized protobuf message to store

updateTimeProvider()

void updateTimeProvider

(

std::function< double()>

time_provider

)

Update the time provider used to create timestamp for the protobufs

Parameters

time_provider

A function that returns the current time in seconds

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

• src/software/logger/proto_logger.h
• src/software/logger/proto_logger.cpp