data Namespace Reference

This namespace implements the data access layer and related components. More...

Namespaces
namespace	cassandra
	This namespace implements a wrapper for the Cassandra C++ driver.

Classes
struct	Amendments
	List of supported amendments. More...
class	AmendmentCenter
	Knowledge center for amendments within XRPL. More...
class	AmendmentCenterInterface
	The interface of an amendment center. More...
class	BackendCounters
	Holds statistics about the backend. More...
class	DatabaseTimeout
	Represents a database timeout error. More...
class	BackendInterface
	The interface to the database used by Clio. More...
class	LedgerCache
	Cache for an entire ledger. More...
class	LedgerCacheInterface
	Cache for an entire ledger. More...
class	FetchLedgerCache
	A simple cache holding one ripple::LedgerHeader to reduce DB lookups. More...
struct	LedgerObject
	Represents an object in the ledger. More...
struct	LedgerPage
	Represents a page of LedgerObjects. More...
struct	BookOffersPage
	Represents a page of book offer objects. More...
struct	TransactionAndMetadata
	Represents a transaction and its metadata bundled together. More...
struct	TransactionsCursor
	Represents a cursor into the transactions table. More...
struct	TransactionsAndCursor
	Represests a bundle of transactions with metadata and a cursor to the next page. More...
struct	NFT
	Represents a NFToken. More...
struct	NFTsAndCursor
	Represents a bundle of NFTs with a cursor to the next page. More...
struct	MPTHoldersAndCursor
	Represents an array of MPTokens. More...
struct	LedgerRange
	Stores a range of sequences as a min and max pair. More...
struct	Amendment
	Represents an amendment in the XRPL. More...
struct	AmendmentKey
	A helper for amendment name to feature conversions. More...

Concepts
concept	SomeBackendCounters
	A concept for a class that can be used to count backend operations.

Typedefs
using	Blob = std::vector<unsigned char>

Functions
std::shared_ptr< BackendInterface >	makeBackend (util::config::ClioConfigDefinition const &config, data::LedgerCacheInterface &cache)
	A factory function that creates the backend based on a config.
template<typename FnType>
auto	retryOnTimeout (FnType func, size_t waitMs=kDEFAULT_WAIT_BETWEEN_RETRY)
	A helper function that catches DatabaseTimeout exceptions and retries indefinitely.
template<typename FnType>
auto	synchronous (FnType &&func)
	Synchronously executes the given function object inside a coroutine.
template<typename FnType>
auto	synchronousAndRetryOnTimeout (FnType &&func)
	Synchronously execute the given function object and retry until no DatabaseTimeout is thrown.

Variables
static constexpr std::size_t	kDEFAULT_WAIT_BETWEEN_RETRY = 500
constexpr ripple::uint256	kFIRST_KEY {"0000000000000000000000000000000000000000000000000000000000000000"}
constexpr ripple::uint256	kLAST_KEY {"FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF"}
constexpr ripple::uint256	kHI192 {"0000000000000000000000000000000000000000000000001111111111111111"}

Detailed Description

This namespace implements the data access layer and related components.

The data layer is responsible for fetching and storing data from the database. Cassandra and ScyllaDB are currently supported via the CassandraBackend implementation.

Function Documentation

makeBackend()

std::shared_ptr< BackendInterface > data::makeBackend ( util::config::ClioConfigDefinition const & config, data::LedgerCacheInterface & cache )

inline

A factory function that creates the backend based on a config.

Parameters

config	The clio config to use
cache	The ledger cache to use

Returns

A shared_ptr<BackendInterface> with the selected implementation

retryOnTimeout()

template<typename FnType>

auto data::retryOnTimeout	(	FnType	func,
		size_t	waitMs = kDEFAULT_WAIT_BETWEEN_RETRY )

A helper function that catches DatabaseTimeout exceptions and retries indefinitely.

Template Parameters

FnType

The type of function object to execute

Parameters

func	The function object to execute
waitMs	Delay between retry attempts

Returns

The same as the return type of func

synchronous()

template<typename FnType>

auto data::synchronous

(

FnType &&

func

)

Synchronously executes the given function object inside a coroutine.

Template Parameters

FnType

The type of function object to execute

Parameters

func	The function object to execute

Returns

The same as the return type of func

synchronousAndRetryOnTimeout()

template<typename FnType>

auto data::synchronousAndRetryOnTimeout

(

FnType &&

func

)

Synchronously execute the given function object and retry until no DatabaseTimeout is thrown.

Template Parameters

FnType

The type of function object to execute

Parameters

func	The function object to execute

Returns

The same as the return type of func