AMMCreate implements Automatic Market Maker(AMM) creation Transactor. More...

#include <AMMCreate.h>

Inheritance diagram for xrpl::AMMCreate:

Collaboration diagram for xrpl::AMMCreate:

[legend]

Public Types
enum class	ConsequencesFactoryType { Normal , Blocker , Custom }

Public Member Functions
	AMMCreate (ApplyContext &ctx)
TER	doApply () override
	Attempt to create the AMM instance.
void	visitInvariantEntry (bool isDelete, SLE::const_ref before, SLE::const_ref after) override
	Inspect a single ledger entry modified by this transaction.
bool	finalizeInvariants (STTx const &tx, TER result, XRPAmount fee, ReadView const &view, beast::Journal const &j) override
	Check transaction-specific post-conditions after all entries have been visited.
ApplyResult	operator() ()
	Process the transaction.
ApplyView &	view ()
ApplyView const &	view () const
TER	checkInvariants (TER result, XRPAmount fee)
	Check all invariants for the current transaction.

Static Public Member Functions
static bool	checkExtraFeatures (PreflightContext const &ctx)
static NotTEC	preflight (PreflightContext const &ctx)
static XRPAmount	calculateBaseFee (ReadView const &view, STTx const &tx)
static TER	preclaim (PreclaimContext const &ctx)
static NotTEC	checkSeqProxy (ReadView const &view, STTx const &tx, beast::Journal j)
static NotTEC	checkPriorTxAndLastLedger (PreclaimContext const &ctx)
static TER	checkFee (PreclaimContext const &ctx, XRPAmount baseFee)
static NotTEC	checkSign (PreclaimContext const &ctx)
static NotTEC	checkBatchSign (PreclaimContext const &ctx)
static XRPAmount	calculateBaseFee (ReadView const &view, STTx const &tx, std::uint32_t extraBaseFeeMultiplier)
template<class T>
static NotTEC	invokePreflight (PreflightContext const &ctx)
template<>
NotTEC	invokePreflight (PreflightContext const &ctx)
template<>
NotTEC	invokePreflight (PreflightContext const &ctx)
static NotTEC	checkGranularSemantics (ReadView const &view, STTx const &tx, std::unordered_set< GranularPermissionType > const &heldGranularPermissions)
	This function can be overridden to introduce additional semantic constraints beyond the granular template validation for granular permissions.
template<class T>
static NotTEC	invokeCheckPermission (ReadView const &view, STTx const &tx)
	Checks whether the transaction is authorized to be executed by the delegated account.
static TER	ticketDelete (ApplyView &view, AccountID const &account, uint256 const &ticketIndex, beast::Journal j)

Static Public Attributes
static constexpr auto	kConsequencesFactory = ConsequencesFactoryType::Normal

Protected Member Functions
TER	apply ()
virtual void	preCompute ()

Static Protected Member Functions
static NotTEC	checkSign (ReadView const &view, ApplyFlags flags, std::optional< uint256 const > const &parentBatchId, AccountID const &idAccount, STObject const &sigObject, beast::Journal const j)
static XRPAmount	minimumFee (ServiceRegistry &registry, XRPAmount baseFee, Fees const &fees, ApplyFlags flags)
	Compute the minimum fee required to process a transaction with a given baseFee based on the current server load.
static XRPAmount	calculateOwnerReserveFee (ReadView const &view, STTx const &tx)
static std::uint32_t	getFlagsMask (PreflightContext const &ctx)
static NotTEC	preflightSigValidated (PreflightContext const &ctx)
static bool	validDataLength (std::optional< Slice > const &slice, std::size_t maxLength)
template<class T>
static bool	validNumericRange (std::optional< T > value, T max, T min=T{})
template<class T, class Unit>
static bool	validNumericRange (std::optional< T > value, unit::ValueUnit< Unit, T > max, unit::ValueUnit< Unit, T > min=unit::ValueUnit< Unit, T >{})
template<class T>
static bool	validNumericMinimum (std::optional< T > value, T min=T{})
	Minimum will usually be zero.
template<class T, class Unit>
static bool	validNumericMinimum (std::optional< T > value, unit::ValueUnit< Unit, T > min=unit::ValueUnit< Unit, T >{})
	Minimum will usually be zero.

Protected Attributes
ApplyContext &	ctx_
beast::WrappedSink	sink_
beast::Journal const	j_
AccountID const	accountID_
XRPAmount	preFeeBalance_ {}

Private Member Functions
std::pair< TER, XRPAmount >	reset (XRPAmount fee)
	Reset the context, discarding any changes made and adjust the fee.
TER	consumeSeqProxy (SLE::pointer const &sleAccount)
TER	payFee ()
std::tuple< TER, XRPAmount, bool >	processPersistentChanges (TER result, XRPAmount fee)
void	trapTransaction (uint256) const
TER	checkTransactionInvariants (TER result, XRPAmount fee)
	Check transaction-specific invariants only.

Static Private Member Functions
static NotTEC	checkPermission (ReadView const &view, STTx const &tx, std::unordered_set< GranularPermissionType > &heldGranularPermissions)
static NotTEC	checkSingleSign (ReadView const &view, AccountID const &idSigner, AccountID const &idAccount, SLE::const_pointer sleAccount, beast::Journal const j)
static NotTEC	checkMultiSign (ReadView const &view, ApplyFlags flags, AccountID const &id, STObject const &sigObject, beast::Journal const j)
static NotTEC	preflight1 (PreflightContext const &ctx, std::uint32_t flagMask)
	Performs early sanity checks on the account and fee fields.
static NotTEC	preflight2 (PreflightContext const &ctx)
	Checks whether the signature appears valid.
static NotTEC	preflightUniversal (PreflightContext const &ctx)
	Universal validations.

Detailed Description

AMMCreate implements Automatic Market Maker(AMM) creation Transactor.

It creates a new AMM instance with two tokens. Any trader, or Liquidity Provider (LP), can create the AMM instance and receive in return shares of the AMM pool in the form of LPTokens. The number of tokens that LP gets are determined by LPTokens = sqrt(A * B), where A and B is the current composition of the AMM pool. LP can add (AMMDeposit) or withdraw (AMMWithdraw) tokens from AMM and AMM can be used transparently in the payment or offer crossing transactions. Trading fee is charged to the traders for the trades executed against AMM instance. The fee is added to the AMM pool and distributed to the LPs in proportion to the LPTokens upon liquidity removal. The fee can be voted on by LP's (AMMVote). LP's can continuously bid (AMMBid) for the 24 hour auction slot, which enables LP's to trade at zero trading fee. AMM instance creates AccountRoot object with disabled master key for book-keeping of XRP balance if one of the tokens is XRP, a trustline for each IOU token, a trustline to keep track of LPTokens, and ltAMM ledger object. AccountRoot ID is generated internally from the parent's hash. ltAMM's object ID is hash{token1.currency, token1.issuer, token2.currency, token2.issuer}, where issue1 < issue2. ltAMM object provides mapping from the hash to AccountRoot ID and contains: AMMAccount - AMM AccountRoot ID. TradingFee - AMM voted TradingFee. VoteSlots - Array of VoteEntry, contains fee vote information. AuctionSlot - Auction slot, contains discounted fee bid information. LPTokenBalance - LPTokens outstanding balance. AMMToken - currency/issuer information for AMM tokens. AMMDeposit, AMMWithdraw, AMMVote, and AMMBid transactions use the hash to access AMM instance.

See also: XLS30d:Creating AMM instance on XRPL

Definition at line 37 of file tx/transactors/dex/AMMCreate.h.

Member Enumeration Documentation

◆ ConsequencesFactoryType

enum class xrpl::Transactor::ConsequencesFactoryType

stronginherited

Enumerator
Normal
Blocker
Custom

Definition at line 129 of file Transactor.h.

Constructor & Destructor Documentation

◆ AMMCreate()

xrpl::AMMCreate::AMMCreate ( ApplyContext & ctx )

explicit

Definition at line 42 of file tx/transactors/dex/AMMCreate.h.

Member Function Documentation

◆ checkExtraFeatures()

bool xrpl::AMMCreate::checkExtraFeatures ( PreflightContext const & ctx )

static

Definition at line 42 of file AMMCreate.cpp.

◆ preflight()

NotTEC xrpl::AMMCreate::preflight ( PreflightContext const & ctx )

static

Definition at line 55 of file AMMCreate.cpp.

◆ calculateBaseFee() [1/2]

XRPAmount xrpl::AMMCreate::calculateBaseFee	(	ReadView const &	view,
		STTx const &	tx )

static

Definition at line 88 of file AMMCreate.cpp.

◆ preclaim()

TER xrpl::AMMCreate::preclaim ( PreclaimContext const & ctx )

static

Definition at line 95 of file AMMCreate.cpp.

◆ doApply()

TER xrpl::AMMCreate::doApply ( )

overridevirtual

Attempt to create the AMM instance.

Implements xrpl::Transactor.

Definition at line 379 of file AMMCreate.cpp.

◆ visitInvariantEntry()

void xrpl::AMMCreate::visitInvariantEntry	(	bool	isDelete,
		SLE::const_ref	before,
		SLE::const_ref	after )

overridevirtual

Inspect a single ledger entry modified by this transaction.

Called once for every SLE created, modified, or deleted by the transaction, before finalizeInvariants. Implementations should accumulate whatever state they need to verify transaction-specific post-conditions.

Parameters

isDelete	true if the entry was erased from the ledger.
before	the entry's state before the transaction (nullptr for newly created entries).
after	the entry's state as supplied by the apply logic for this transaction. For deletions, this is the SLE being erased and is not guaranteed to be null; callers must use isDelete rather than after == nullptr to detect deletions.

Implements xrpl::Transactor.

Definition at line 393 of file AMMCreate.cpp.

◆ finalizeInvariants()

bool xrpl::AMMCreate::finalizeInvariants	(	STTx const &	tx,
		TER	result,
		XRPAmount	fee,
		ReadView const &	view,
		beast::Journal const &	j )

nodiscardoverridevirtual

Check transaction-specific post-conditions after all entries have been visited.

Called once after every modified ledger entry has been passed to visitInvariantEntry. Returns true if all transaction-specific invariants hold, or false to fail the transaction with tecINVARIANT_FAILED.

Parameters

tx	the transaction being applied.
result	the tentative TER result so far.
fee	the fee consumed by the transaction.
view	read-only view of the ledger after the transaction.
j	journal for logging invariant failures.

Returns: true if all invariants pass; false otherwise.

Implements xrpl::Transactor.

Definition at line 399 of file AMMCreate.cpp.

◆ operator()()

ApplyResult xrpl::Transactor::operator() ( )

inherited

Process the transaction.

Definition at line 1318 of file Transactor.cpp.

◆ view() [1/2]

ApplyView & xrpl::Transactor::view ( )

inherited

Definition at line 136 of file Transactor.h.

◆ view() [2/2]

ApplyView const & xrpl::Transactor::view ( ) const

nodiscardinherited

Definition at line 142 of file Transactor.h.

◆ checkInvariants()

TER xrpl::Transactor::checkInvariants	(	TER	result,
		XRPAmount	fee )

nodiscardinherited

Check all invariants for the current transaction.

Runs transaction-specific invariants first (visitInvariantEntry + finalizeInvariants), then protocol-level invariants. Both layers always run; the worst failure code is returned.

Parameters

result	the tentative TER from transaction processing.
fee	the fee consumed by the transaction.

Returns: the final TER after all invariant checks.

Definition at line 1301 of file Transactor.cpp.

◆ checkSeqProxy()

NotTEC xrpl::Transactor::checkSeqProxy	(	ReadView const &	view,
		STTx const &	tx,
		beast::Journal	j )

staticinherited

Definition at line 487 of file Transactor.cpp.

◆ checkPriorTxAndLastLedger()

NotTEC xrpl::Transactor::checkPriorTxAndLastLedger ( PreclaimContext const & ctx )

staticinherited

Definition at line 552 of file Transactor.cpp.

◆ checkFee()

TER xrpl::Transactor::checkFee	(	PreclaimContext const &	ctx,
		XRPAmount	baseFee )

staticinherited

Definition at line 400 of file Transactor.cpp.

◆ checkSign() [1/2]

NotTEC xrpl::Transactor::checkSign ( PreclaimContext const & ctx )

staticinherited

Definition at line 771 of file Transactor.cpp.

◆ checkSign() [2/2]

NotTEC xrpl::Transactor::checkSign	(	ReadView const &	view,
		ApplyFlags	flags,
		std::optional< uint256 const > const &	parentBatchId,
		AccountID const &	idAccount,
		STObject const &	sigObject,
		beast::Journal const	j )

staticprotectedinherited

Definition at line 705 of file Transactor.cpp.

◆ checkBatchSign()

NotTEC xrpl::Transactor::checkBatchSign ( PreclaimContext const & ctx )

staticinherited

Definition at line 779 of file Transactor.cpp.

◆ calculateBaseFee() [2/2]

XRPAmount xrpl::Transactor::calculateBaseFee	(	ReadView const &	view,
		STTx const &	tx,
		std::uint32_t	extraBaseFeeMultiplier )

staticinherited

Definition at line 360 of file Transactor.cpp.

◆ invokePreflight() [1/3]

template<class T>

NotTEC xrpl::Transactor::invokePreflight ( PreflightContext const & ctx )

staticinherited

Definition at line 530 of file Transactor.h.

◆ invokePreflight() [2/3]

template<>

NotTEC xrpl::Transactor::invokePreflight ( PreflightContext const & ctx )

staticinherited

◆ invokePreflight() [3/3]

template<>

NotTEC xrpl::Transactor::invokePreflight ( PreflightContext const & ctx )

staticinherited

Definition at line 33 of file Change.cpp.

◆ checkGranularSemantics()

NotTEC xrpl::Transactor::checkGranularSemantics	(	ReadView const &	view,
		STTx const &	tx,
		std::unordered_set< GranularPermissionType > const &	heldGranularPermissions )

staticinherited

This function can be overridden to introduce additional semantic constraints beyond the granular template validation for granular permissions.

It is called by the base invokeCheckPermission method only after the transaction has successfully passed checkGranularSandbox.

Definition at line 238 of file Transactor.h.

◆ invokeCheckPermission()

template<class T>

NotTEC xrpl::Transactor::invokeCheckPermission	(	ReadView const &	view,
		STTx const &	tx )

staticinherited

Checks whether the transaction is authorized to be executed by the delegated account.

This function enforces the strict permission check hierarchy. It is explicitly designed NOT to be overridden. Derived transactors must instead implement checkGranularSemantics to add custom validation logic for granular permissions.

The evaluation proceeds as follows:

If transaction-level permission is granted, the function immediately returns tesSUCCESS.
If transaction-level permission is not granted, the function checks whether the transaction matches the granular permission template defined in permissions.macro. If it does, it then calls checkGranularSemantics to perform any additional, fine-grained validation.

Definition at line 261 of file Transactor.h.

◆ ticketDelete()

TER xrpl::Transactor::ticketDelete	(	ApplyView &	view,
		AccountID const &	account,
		uint256 const &	ticketIndex,
		beast::Journal	j )

staticinherited

Definition at line 597 of file Transactor.cpp.

◆ apply()

TER xrpl::Transactor::apply ( )

protectedinherited

Definition at line 669 of file Transactor.cpp.

◆ preCompute()

void xrpl::Transactor::preCompute ( )

protectedvirtualinherited

Reimplemented in xrpl::Change, and xrpl::SignerListSet.

Definition at line 663 of file Transactor.cpp.

◆ minimumFee()

XRPAmount xrpl::Transactor::minimumFee	(	ServiceRegistry &	registry,
		XRPAmount	baseFee,
		Fees const &	fees,
		ApplyFlags	flags )

staticprotectedinherited

Compute the minimum fee required to process a transaction with a given baseFee based on the current server load.

Parameters

registry	The service registry.
baseFee	The base fee of a candidate transaction

See also: xrpl::calculateBaseFee

Parameters

fees	Fee settings from the current ledger
flags	Transaction processing fees

Definition at line 390 of file Transactor.cpp.

◆ calculateOwnerReserveFee()

XRPAmount xrpl::Transactor::calculateOwnerReserveFee	(	ReadView const &	view,
		STTx const &	tx )

staticprotectedinherited

Definition at line 370 of file Transactor.cpp.

◆ getFlagsMask()

std::uint32_t xrpl::Transactor::getFlagsMask ( PreflightContext const & ctx )

staticprotectedinherited

Definition at line 300 of file Transactor.cpp.

◆ preflightSigValidated()

NotTEC xrpl::Transactor::preflightSigValidated ( PreflightContext const & ctx )

staticprotectedinherited

Definition at line 306 of file Transactor.cpp.

◆ validDataLength()

bool xrpl::Transactor::validDataLength	(	std::optional< Slice > const &	slice,
		std::size_t	maxLength )

staticprotectedinherited

Definition at line 292 of file Transactor.cpp.

◆ validNumericRange() [1/2]

template<class T>

bool xrpl::Transactor::validNumericRange	(	std::optional< T >	value,
		T	max,
		T	min = T{} )

staticprotectedinherited

Definition at line 559 of file Transactor.h.

◆ validNumericRange() [2/2]

template<class T, class Unit>

bool xrpl::Transactor::validNumericRange	(	std::optional< T >	value,
		unit::ValueUnit< Unit, T >	max,
		unit::ValueUnit< Unit, T >	min = unit::ValueUnit<Unit, T>{} )

staticprotectedinherited

Definition at line 568 of file Transactor.h.

◆ validNumericMinimum() [1/2]

template<class T>

bool xrpl::Transactor::validNumericMinimum	(	std::optional< T >	value,
		T	min = T{} )

staticprotectedinherited

Minimum will usually be zero.

Definition at line 578 of file Transactor.h.

◆ validNumericMinimum() [2/2]

template<class T, class Unit>

bool xrpl::Transactor::validNumericMinimum	(	std::optional< T >	value,
		unit::ValueUnit< Unit, T >	min = unit::ValueUnit<Unit, T>{} )

staticprotectedinherited

Minimum will usually be zero.

Definition at line 587 of file Transactor.h.

◆ checkPermission()

NotTEC xrpl::Transactor::checkPermission	(	ReadView const &	view,
		STTx const &	tx,
		std::unordered_set< GranularPermissionType > &	heldGranularPermissions )

staticprivateinherited

Definition at line 312 of file Transactor.cpp.

◆ reset()

std::pair< TER, XRPAmount > xrpl::Transactor::reset ( XRPAmount fee )

privateinherited

Reset the context, discarding any changes made and adjust the fee.

Parameters

fee	The transaction fee to be charged.

Returns: A pair containing the transaction result and the actual fee charged.

Definition at line 1098 of file Transactor.cpp.

◆ consumeSeqProxy()

TER xrpl::Transactor::consumeSeqProxy ( SLE::pointer const & sleAccount )

privateinherited

Definition at line 580 of file Transactor.cpp.

◆ payFee()

TER xrpl::Transactor::payFee ( )

privateinherited

Definition at line 467 of file Transactor.cpp.

◆ processPersistentChanges()

std::tuple< TER, XRPAmount, bool > xrpl::Transactor::processPersistentChanges	(	TER	result,
		XRPAmount	fee )

privateinherited

Definition at line 1155 of file Transactor.cpp.

◆ checkSingleSign()

NotTEC xrpl::Transactor::checkSingleSign	(	ReadView const &	view,
		AccountID const &	idSigner,
		AccountID const &	idAccount,
		SLE::const_pointer	sleAccount,
		beast::Journal const	j )

staticprivateinherited

Definition at line 823 of file Transactor.cpp.

◆ checkMultiSign()

NotTEC xrpl::Transactor::checkMultiSign	(	ReadView const &	view,
		ApplyFlags	flags,
		AccountID const &	id,
		STObject const &	sigObject,
		beast::Journal const	j )

staticprivateinherited

Definition at line 855 of file Transactor.cpp.

◆ trapTransaction()

void xrpl::Transactor::trapTransaction ( uint256 txHash ) const

privateinherited

Definition at line 1149 of file Transactor.cpp.

◆ preflight1()

NotTEC xrpl::Transactor::preflight1	(	PreflightContext const &	ctx,
		std::uint32_t	flagMask )

staticprivateinherited

Performs early sanity checks on the account and fee fields.

(And passes flagMask to preflight0)

Do not try to call preflight1 from preflight() in derived classes. See the description of invokePreflight for details.

Definition at line 173 of file Transactor.cpp.

◆ preflight2()

NotTEC xrpl::Transactor::preflight2 ( PreflightContext const & ctx )

staticprivateinherited

Checks whether the signature appears valid.

Do not try to call preflight2 from preflight() in derived classes. See the description of invokePreflight for details.

Definition at line 237 of file Transactor.cpp.

◆ preflightUniversal()

NotTEC xrpl::Transactor::preflightUniversal ( PreflightContext const & ctx )

staticprivateinherited

Universal validations.

Valid MPTAmount and XRPAmount

Do not try to call preflightUniversal from preflight() in derived classes. See the description of invokePreflight for details.

Definition at line 273 of file Transactor.cpp.

◆ checkTransactionInvariants()

TER xrpl::Transactor::checkTransactionInvariants	(	TER	result,
		XRPAmount	fee )

nodiscardprivateinherited

Check transaction-specific invariants only.

Walks every modified ledger entry via visitInvariantEntry, then calls finalizeInvariants on the derived transactor. Returns tecINVARIANT_FAILED if any transaction invariant is violated.

Parameters

result	the tentative TER from transaction processing.
fee	the fee consumed by the transaction.

Returns: the original result if all invariants pass, or tecINVARIANT_FAILED otherwise.

Definition at line 1267 of file Transactor.cpp.

Member Data Documentation

◆ kConsequencesFactory

auto xrpl::AMMCreate::kConsequencesFactory = ConsequencesFactoryType::Normal

staticconstexpr

Definition at line 40 of file tx/transactors/dex/AMMCreate.h.

◆ ctx_

ApplyContext& xrpl::Transactor::ctx_

protectedinherited

Definition at line 116 of file Transactor.h.

◆ sink_

beast::WrappedSink xrpl::Transactor::sink_

protectedinherited

Definition at line 117 of file Transactor.h.

◆ j_

beast::Journal const xrpl::Transactor::j_

protectedinherited

Definition at line 118 of file Transactor.h.

◆ accountID_

AccountID const xrpl::Transactor::accountID_

protectedinherited

Definition at line 120 of file Transactor.h.

◆ preFeeBalance_

XRPAmount xrpl::Transactor::preFeeBalance_ {}

protectedinherited

Definition at line 121 of file Transactor.h.

Public Types

Public Member Functions

Static Public Member Functions

Static Public Attributes

Protected Member Functions

Static Protected Member Functions

Protected Attributes

Private Member Functions

Static Private Member Functions

Detailed Description

Member Enumeration Documentation

◆ ConsequencesFactoryType

Constructor & Destructor Documentation

◆ AMMCreate()

Member Function Documentation

◆ checkExtraFeatures()

◆ preflight()

◆ calculateBaseFee() [1/2]

◆ preclaim()

◆ doApply()

◆ visitInvariantEntry()

◆ finalizeInvariants()

◆ operator()()

◆ view() [1/2]

◆ view() [2/2]

◆ checkInvariants()

◆ checkSeqProxy()

◆ checkPriorTxAndLastLedger()

◆ checkFee()

◆ checkSign() [1/2]

◆ checkSign() [2/2]

◆ checkBatchSign()

◆ calculateBaseFee() [2/2]

◆ invokePreflight() [1/3]

◆ invokePreflight() [2/3]

◆ invokePreflight() [3/3]

◆ checkGranularSemantics()

◆ invokeCheckPermission()

◆ ticketDelete()

◆ apply()

◆ preCompute()

◆ minimumFee()

◆ calculateOwnerReserveFee()

◆ getFlagsMask()

◆ preflightSigValidated()

◆ validDataLength()

◆ validNumericRange() [1/2]

◆ validNumericRange() [2/2]

◆ validNumericMinimum() [1/2]

◆ validNumericMinimum() [2/2]

◆ checkPermission()

◆ reset()

◆ consumeSeqProxy()

◆ payFee()

◆ processPersistentChanges()

◆ checkSingleSign()

◆ checkMultiSign()

◆ trapTransaction()

◆ preflight1()

◆ preflight2()

◆ preflightUniversal()

◆ checkTransactionInvariants()

Member Data Documentation

◆ kConsequencesFactory

◆ ctx_

◆ sink_

◆ j_

◆ accountID_

◆ preFeeBalance_