#include <file_manager_strategy.h>

Inheritance diagram for Aws::FileManagement::FileManagerStrategy:

Public Member Functions
	FileManagerStrategy (const FileManagerStrategyOptions &options)

bool	isDataAvailable () override

bool	isDeleteStaleData () override

DataToken	read (std::string &data) override

void	resolve (const DataToken &token, bool is_success) override

bool	shutdown () override

bool	start () override

void	write (const std::string &data) override

	~FileManagerStrategy () override=default

Public Member Functions inherited from Aws::FileManagement::DataManagerStrategy
	DataManagerStrategy ()=default

	~DataManagerStrategy () override=default

Public Member Functions inherited from Service
ServiceState	getState ()

virtual std::string	getStatusString ()

	Service ()

virtual	~Service ()=default

Protected Member Functions
std::string	getActiveWriteFile ()

std::string	getFileToRead ()

Protected Member Functions inherited from Service
void	setState (ServiceState new_state)

Private Member Functions
void	addFilePathToStorage (const std::experimental::filesystem::path &file_path)

void	checkIfStorageLimitHasBeenReached (const uintmax_t &new_data_size)

void	checkIfWriteFileShouldRotate (const uintmax_t &new_data_size)

void	deleteFile (const std::string &file_path)

void	deleteOldestFile ()

void	discoverStoredFiles ()

void	initializeStorage ()

void	initializeTokenStore ()

void	rotateWriteFile ()

void	validateOptions ()

Private Attributes
std::string	active_read_file_

std::mutex	active_read_file_mutex_

std::unique_ptr< std::ifstream >	active_read_file_stream_

std::string	active_write_file_

std::mutex	active_write_file_mutex_

std::atomic< size_t >	active_write_file_size_ {}

FileManagerStrategyOptions	options_

std::list< std::string >	stored_files_

std::atomic< size_t >	stored_files_size_ {}

std::unique_ptr< TokenStore >	token_store_

Detailed Description

Manages how files are split up, which files to write to and read when requested.

Definition at line 285 of file file_manager_strategy.h.

Constructor & Destructor Documentation

Aws::FileManagement::FileManagerStrategy::FileManagerStrategy ( const FileManagerStrategyOptions & options )

explicit

Definition at line 231 of file file_manager_strategy.cpp.

Aws::FileManagement::FileManagerStrategy::~FileManagerStrategy ( )

overridedefault

Member Function Documentation

void Aws::FileManagement::FileManagerStrategy::addFilePathToStorage ( const std::experimental::filesystem::path & file_path )

private

Adds a file path to the stored_files_ list

Parameters

file_path the path to the file

Definition at line 410 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::checkIfStorageLimitHasBeenReached ( const uintmax_t & new_data_size )

private

Checks if all the space taken up by offline storage exceeds the setting storage_limit_in_kb. If it has reached that amount it deletes the oldest file from disk.

Parameters

new_data_size the size of all files on disk in bytes

Definition at line 452 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::checkIfWriteFileShouldRotate ( const uintmax_t & new_data_size )

private

Checks if the active_write_file_ size is equal to or greater than maximum_file_size_in_kb in size. If it is then it calls rotateWriteFile.

Parameters

new_data_size the size of the active_write_file in bytes

Definition at line 442 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::deleteFile ( const std::string & file_path )

private

Delete a file at this path. Used when all data from a file has been uploaded successfully or when the offline file storage has reached storage_limit_in_kb

Parameters

file_path path to the file to be deleted

Definition at line 383 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::deleteOldestFile ( )

private

Deletes the oldest file in offline storage. Cannot delete the active_write_file_

Definition at line 461 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::discoverStoredFiles ( )

private

Finds any offline storage files on disk that are awaiting upload.

Definition at line 370 of file file_manager_strategy.cpp.

std::string Aws::FileManagement::FileManagerStrategy::getActiveWriteFile ( )

inlineprotected

Returns the active write file. Getter used for testing.

Returns: the file the system is actively writing to

Definition at line 359 of file file_manager_strategy.h.

std::string Aws::FileManagement::FileManagerStrategy::getFileToRead ( )

protected

Returns the next file from storage that should be read from. Prioritizes newest files first.

Returns: a path to the file to be read

Exceptions

std::runtime_error If there are no files available to read

Definition at line 390 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::initializeStorage ( )

private

Initializes the folder that offline data will be saved to, creating it if it doesn't already exist.

Definition at line 250 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::initializeTokenStore ( )

private

Creates the TokenStore and runs its initialize method

Definition at line 260 of file file_manager_strategy.cpp.

bool Aws::FileManagement::FileManagerStrategy::isDataAvailable ( )

overridevirtual

Returns true if there is offline data on disk awaiting to be uploaded, false otherwise.

Returns: bool if there is data available

Implements Aws::FileManagement::DataManagerStrategy.

Definition at line 267 of file file_manager_strategy.cpp.

bool Aws::FileManagement::FileManagerStrategy::isDeleteStaleData ( )

overridevirtual

Deletes stale data that won't be accepted by the CloudWatch API. This is done in a separate method so it doesn't block the current publishing task after reading the data.

Implements Aws::FileManagement::DataManagerStrategy.

Definition at line 276 of file file_manager_strategy.cpp.

DataToken Aws::FileManagement::FileManagerStrategy::read ( std::string & data )

overridevirtual

Reads a line of data from file storage. The most recent data in storage is read first. This returns a DataToken which should be passed to resolve() when the caller is done with it.

Parameters

std::string a string of data which is read from storage

Returns: DataToken that should be passed to resolve() when done

Implements Aws::FileManagement::DataManagerStrategy.

Definition at line 300 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::resolve	(	const DataToken &	token,
		bool	is_success
	)

overridevirtual

Resolves a DataToken. If the data associated with the token was successfully sent then the FileManagerStrategy knows it now longer needs to hold onto it. If the data was not successfully sent then the FileManagerStrategy knows it needs to hold onto it and re-send that data in the next read.

Parameters

DataToken	the token to be resolved
is_success	whether the data was successfully sent or not

Implements Aws::FileManagement::DataManagerStrategy.

Definition at line 335 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::rotateWriteFile ( )

private

Moves the active_write_file into stored_files list and creates a new file setting the active_write_file_ to that new file.

Definition at line 415 of file file_manager_strategy.cpp.

bool Aws::FileManagement::FileManagerStrategy::shutdown ( )

overridevirtual

Saves all in flight tokens and information out to disk so that on startup the FileManagerStrategy can start reading from the same file location that it was up to previously.

Returns: bool whether it shutdown successfully

Reimplemented from Service.

Definition at line 363 of file file_manager_strategy.cpp.

bool Aws::FileManagement::FileManagerStrategy::start ( )

overridevirtual

Starts the FileManagerStrategy, this does any initialization I/O tasks required. It is separate from the constructor to keep the construction of this class lightweight. It checks if there are any existing offline storage files on disk, initializes the token store, and ensures there is a new file ready to write to if uploads fail.

Returns: bool whether it started successfully or not

Reimplemented from Service.

Definition at line 238 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::validateOptions ( )

private

Validates options that were passed to the constructor of this class. Also sanitizes any paths or slightly incorrect options.

Definition at line 246 of file file_manager_strategy.cpp.

void Aws::FileManagement::FileManagerStrategy::write ( const std::string & data )

overridevirtual

Write a line of data to to file storage.

Parameters

std::string a string of data to write to storage

Implements Aws::FileManagement::DataManagerStrategy.

Definition at line 280 of file file_manager_strategy.cpp.

Member Data Documentation

std::string Aws::FileManagement::FileManagerStrategy::active_read_file_

private

The file we are currently reading from. The FileManagerStrategy only reads from one file at a time.

Definition at line 455 of file file_manager_strategy.h.

std::mutex Aws::FileManagement::FileManagerStrategy::active_read_file_mutex_

private

A lock on the active read file, to ensure that it does not get deleted while it is being read from.

Definition at line 467 of file file_manager_strategy.h.

std::unique_ptr<std::ifstream> Aws::FileManagement::FileManagerStrategy::active_read_file_stream_

private

An IOStream for the active_read_file. Kept open so that it's easy to move to the next point in the file with each read instead of continually opening a new stream each time.

Definition at line 461 of file file_manager_strategy.h.

std::string Aws::FileManagement::FileManagerStrategy::active_write_file_

private

Path to the file we're currently writing to. This file cannot be read from or deleted.

Definition at line 438 of file file_manager_strategy.h.

std::mutex Aws::FileManagement::FileManagerStrategy::active_write_file_mutex_

private

A lock on the active write file, to ensure that when it's rotated nothing is writing to it at the same time.

Definition at line 449 of file file_manager_strategy.h.

std::atomic<size_t> Aws::FileManagement::FileManagerStrategy::active_write_file_size_ {}

private

The size of the active_write_file. Stored here to minimize disk reads.

Definition at line 443 of file file_manager_strategy.h.

FileManagerStrategyOptions Aws::FileManagement::FileManagerStrategy::options_

private

Options for how and where to store files, and maximum file sizes.

Definition at line 472 of file file_manager_strategy.h.

std::list<std::string> Aws::FileManagement::FileManagerStrategy::stored_files_

private

Stored files to read from in order from most recent to oldest.

Definition at line 428 of file file_manager_strategy.h.

std::atomic<size_t> Aws::FileManagement::FileManagerStrategy::stored_files_size_ {}

private

Disk space used by all stored files. Does not include active_write_file_size_.

Definition at line 433 of file file_manager_strategy.h.

std::unique_ptr<TokenStore> Aws::FileManagement::FileManagerStrategy::token_store_

private

Stores which tokens to read from.

Definition at line 477 of file file_manager_strategy.h.

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

Public Member Functions

Protected Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation