Implement native support for Price Oracles.
A Price Oracle is used to bring real-world data, such as market prices,
onto the blockchain, enabling dApps to access and utilize information
that resides outside the blockchain.
Add Price Oracle functionality:
- OracleSet: create or update the Oracle object
- OracleDelete: delete the Oracle object
To support this functionality add:
- New RPC method, `get_aggregate_price`, to calculate aggregate price for a token pair of the specified oracles
- `ltOracle` object
The `ltOracle` object maintains:
- Oracle Owner's account
- Oracle's metadata
- Up to ten token pairs with the scaled price
- The last update time the token pairs were updated
Add Oracle unit-tests
Implement native support for W3C DIDs.
Add a new ledger object: `DID`.
Add two new transactions:
1. `DIDSet`: create or update the `DID` object.
2. `DIDDelete`: delete the `DID` object.
This meets the requirements specified in the DID v1.0 specification
currently recommended by the W3C Credentials Community Group.
The DID format for the XRP Ledger conforms to W3C DID standards.
The objects can be created and owned by any XRPL account holder.
The transactions can be integrated by any service, wallet, or application.
A bridge connects two blockchains: a locking chain and an issuing
chain (also called a mainchain and a sidechain). Both are independent
ledgers, with their own validators and potentially their own custom
transactions. Importantly, there is a way to move assets from the
locking chain to the issuing chain and a way to return those assets from
the issuing chain back to the locking chain: the bridge. This key
operation is called a cross-chain transfer. A cross-chain transfer is
not a single transaction. It happens on two chains, requires multiple
transactions, and involves an additional server type called a "witness".
A bridge does not exchange assets between two ledgers. Instead, it locks
assets on one ledger (the "locking chain") and represents those assets
with wrapped assets on another chain (the "issuing chain"). A good model
to keep in mind is a box with an infinite supply of wrapped assets.
Putting an asset from the locking chain into the box will release a
wrapped asset onto the issuing chain. Putting a wrapped asset from the
issuing chain back into the box will release one of the existing locking
chain assets back onto the locking chain. There is no other way to get
assets into or out of the box. Note that there is no way for the box to
"run out of" wrapped assets - it has an infinite supply.
Co-authored-by: Gregory Popovitch <greg7mdp@gmail.com>
Add AMM functionality:
- InstanceCreate
- Deposit
- Withdraw
- Governance
- Auctioning
- payment engine integration
To support this functionality, add:
- New RPC method, `amm_info`, to fetch pool and LPT balances
- AMM Root Account
- trust line for each IOU AMM token
- trust line to track Liquidity Provider Tokens (LPT)
- `ltAMM` object
The `ltAMM` object tracks:
- fee votes
- auction slot bids
- AMM tokens pair
- total outstanding tokens balance
- `AMMID` to AMM `RootAccountID` mapping
Add new classes to facilitate AMM integration into the payment engine.
`BookStep` uses these classes to infer if AMM liquidity can be consumed.
The AMM formula implementation uses the new Number class added in #4192.
IOUAmount and STAmount use Number arithmetic.
Add AMM unit tests for all features.
AMM requires the following amendments:
- featureAMM
- fixUniversalNumber
- featureFlowCross
Notes:
- Current trading fee threshold is 1%
- AMM currency is generated by: 0x03 + 152 bits of sha256{cur1, cur2}
- Current max AMM Offers is 30
---------
Co-authored-by: Howard Hinnant <howard.hinnant@gmail.com>
Apply a minor cleanup in `TypedField`:
* Remove a non-working and unused move constructor.
* Constrain the remaining constructor to not be overly generic enough as
to be used as a copy or move constructor.
Without the protocol amendment introduced by this commit, an NFT ID can
be reminted in this manner:
1. Alice creates an account and mints an NFT.
2. Alice burns the NFT with an `NFTokenBurn` transaction.
3. Alice deletes her account with an `AccountDelete` transaction.
4. Alice re-creates her account.
5. Alice mints an NFT with an `NFTokenMint` transaction with params:
`NFTokenTaxon` = 0, `Flags` = 9).
This will mint a NFT with the same `NFTokenID` as the one minted in step
1. The params that construct the NFT ID will cause a collision in
`NFTokenID` if their values are equal before and after the remint.
With the `fixNFTokenRemint` amendment, there is a new sequence number
construct which avoids this scenario:
- A new `AccountRoot` field, `FirstNFTSequence`, stays constant over
time.
- This field is set to the current account sequence when the account
issues their first NFT.
- Otherwise, it is not set.
- The sequence of a newly-minted NFT is computed by: `FirstNFTSequence +
MintedNFTokens`.
- `MintedNFTokens` is then incremented by 1 for each mint.
Furthermore, there is a new account deletion restriction:
- An account can only be deleted if `FirstNFTSequence + MintedNFTokens +
256` is less than the current ledger sequence.
- 256 was chosen because it already exists in the current account
deletion constraint.
Without this restriction, an NFT may still be remintable. Example
scenario:
1. Alice's account sequence is at 1.
2. Bob is Alice's authorized minter.
3. Bob mints 500 NFTs for Alice. The NFTs will have sequences 1-501, as
NFT sequence is computed by `FirstNFTokenSequence + MintedNFTokens`).
4. Alice deletes her account at ledger 257 (as required by the existing
`AccountDelete` amendment).
5. Alice re-creates her account at ledger 258.
6. Alice mints an NFT. `FirstNFTokenSequence` initializes to her account
sequence (258), and `MintedNFTokens` initializes as 0. This
newly-minted NFT would have a sequence number of 258, which is a
duplicate of what she issued through authorized minting before she
deleted her account.
---------
Signed-off-by: Shawn Xie <shawnxie920@gmail.com>
* Introduces amendment `XRPFees`
* Convert fee voting and protocol messages to use XRPAmounts
* Includes Validations, Change transactions, the "Fees" ledger object,
and subscription messages
* Improve handling of 0 drop reference fee with TxQ. For use with networks that do not want to require fees
* Note that fee escalation logic is still in place, which may cause the
open ledger fee to rise if the network is busy. 0 drop transactions
will still queue, and fee escalation can be effectively disabled by
modifying the configuration on all nodes
* Change default network reserves to match Mainnet
* Name the new SFields *Drops (not *XRP)
* Reserve SField IDs for Hooks
* Clarify comments explaining the ttFEE transaction field validation
In order to preserve the Hooks ABI, it is important that field
values used for hooks be stable going forward.
This commit reserves the required codes so that they will not
be repurposed before Hooks can be proposed for inclusion in
the codebase.
There have been cases in the past where SFields have been defined
in such a way that they did not follow our conventions. In
particular, the string representation of an SField should match
the in-code name of the SField.
This change leverages the preprocessor to encourage SFields to
be properly constructed.
The suffixes of SField types are changed to be the same as
the suffixes of corresponding SerializedTypeIDs. This allows
The preprocessor to match types using simple name pasting.
Since the string representation of the SField is part of our
stable API, the name of sfPayChannel was changed to sfChannel.
This change allows sfChannel to follow our conventions while
making no changes to our external API.
Tickets are a mechanism to allow for the "out-of-order" execution of
transactions on the XRP Ledger.
This commit, if merged, reworks the existing support for tickets and
introduces support for 'ticket batching', completing the feature set
needed for tickets.
The code is gated under the newly-introduced `TicketBatch` amendment
and the `Tickets` amendment, which is not presently active on the
network, is being removed.
The specification for this change can be found at:
https://github.com/xrp-community/standards-drafts/issues/16
This change can help improve the liveness of the network during periods of network
instability, by allowing the network to track which validators are presently not online
and to disregard them for the purposes of quorum calculations.
Currently there is no mechanism for a validator to report the
version of the software it is currently running. Such reports
can be useful for those who are developing network monitoring
dashboards and server operators in general.
This commit, if merged, defines an encoding scheme to encode
a version string into a 64-bit unsigned integer and adds an
additional optional field to validations.
This commit piggybacks on "HardenedValidations" amendment to
determine whether version information should be propagated
or not.
The general encoding scheme is:
XXXXXXXX-XXXXXXXX-YYYYYYYY-YYYYYYYY-YYYYYYYY-YYYYYYYY-YYYYYYYY-YYYYYYYY
X: 16 bits identifying the particular implementation
Y: 48 bits of data specific to the implementation
The rippled-specific format (implementation ID is: 0x18 0x3B) is:
00011000-00111011-MMMMMMMM-mmmmmmmm-pppppppp-TTNNNNNN-00000000-00000000
M: 8-bit major version (0-255)
m: 8-bit minor version (0-255)
p: 8-bit patch version (0-255)
T: 11 if neither an RC nor a beta
10 if an RC
01 if a beta
N: 6-bit rc/beta number (1-63)
This commit introduces the "HardenedValidations" amendment which,
if enabled, allows validators to include additional information in
their validations that can increase the robustness of consensus.
Specifically, the commit introduces a new optional field that can
be set in validation messages can be used to attest to the hash of
the latest ledger that a validator considers to be fully validated.
Additionally, the commit leverages the previously introduced "cookie"
field to improve the robustness of the network by making it possible
for servers to automatically detect accidental misconfiguration which
results in two or more validators using the same validation key.
