0g-chain/x/swap/keeper/deposit.go
Ruaridh 65052ce31a
Squash merge swap-acceptance branch (#956)
* add failing acceptance test for a user depositing into a pool

* implement GetAccount test helper

* implement swap.MsgDeposit for creating and adding liquidity to a pool

* update aliases, add event types, and fix typo/compiler errors in handler
test

* use only aliases names in handler test (don't use swap types -- ensures
we have run aliasgen), add assertion for even type message

* implement account and module account balance checks in handler test

* fill out handler assertions for testing keeper state and events

* update signed json representation and register swap/MsgDeposit for
proper encoding

* fill out boilerplate to get handler test to compile

* alias gen for pool

* add handling of message type; fill in deposit keeper method for
succesful compile; noop but test assertions now run up to module acc not
nil check

* add module account permissions for swap module -- fixes module account
creation; pass account keeper and supply keeper into swap keeper to
allow the ability to work with user and module accounts

* implement create pool logic for msg deposit; allows creation of a of new
pool, checking params to see if it is allowed.  Initi shares are set,
and senders number of shares are stored

* Swap migrations scaffolding (#925)

* swap module scaffolding

* global swap fee

* can't think of a reason for begin blocker; removing for abci.go for now;

* test pair types; refactor pair name logic; simplify pairs validation and
fix stack overflow error

* check comparison

* use test package

* init swap module genesis

* add basic marshall tests

* remove reward apy from pairs

* fix integration helpers

* use max swap fee constant; fix validation of swap fee; add tests to
cover param validation and param set setup

* use noerror over nil

* start genesis tests

* test param set validation mirrors param validation

* add genesis tests

* remove print statement

* add subtests for genesis test cases; add extra querier test for unknown
route; add keeper params testing

* add spec

* update swagger

* find replace hard -> swap in comments

* remove unused method

* rename pairs to allowed pools; pool is more commonly used, and
allowedPool makes it more clear what swap parameter is for.  In
addition, we won't conflict with Pool data structure for storing a
created pool in the store.

* remove generated link

* missed spec rename

* validate token order for allowed pools

* fix swagger

* json should be snakecase; change allowedPools to allowed_pools

* add legacy types

* add swap genesis to v0_15 migration

* add legacy types

* add swap genesis to v0_15 migration

* migration revisions

Co-authored-by: Nick DeLuca <nickdeluca08@gmail.com>

* keeper todos

* update keeper tests

* type todos

* update types tests

* tx deposit cli cmd

* tx deposit rest

* Swap module simulation scaffolding (#924)

* sims scaffolding

* add noop operation

* genesis revisions

* add param changes

* mvoe persistance methods to main keeper file, consolidate tests

* make helper methods private. they are tested via deposit method, and
unit testing them would make test suite brittle and refactoring
difficult

* use more clear coin variables

* code 1 is reserved, use code 2 and sequence all errors

* remove todo

* Implement deadline for swap module module message. This is implemented in
handler with a interface to easily apply to it to all messages, and
separate msg validation concerns from the keeper

* move allowed pools to params -- let pool and pool_test focus on pool domain logic, not
parameter & governance concerns

* update alias

* add unitless implementatin of constant product liquidity pool to
isolate and enapsulate liquidity logic.  Swap methods interfaces are
added, but implementation not yet added

* nits and todos

* add ErrInvalidPool

* add tests for edge cases around pool depletion; add explicit panic for
edge case that results in a pool reserve being zero; handle pool
reinitialization if it is empty

* touch up comments and flush out the rest of assertions

* add data structures for keeper state storage separate from pool domain
objects, and improve structure for easier querying

* rename pool name to pool key for events

* add support for a denominated pool that uses sdk.Coins and sdk.Coin
arguments, keeping tracking of the units in the base pool.  This gives
nice separation between pool logic, and coin/denom logic

* refactor keeper to use new records for storage, and implement pool
deposit using the denominated pool

* address previous PR comment - reminder for migration if changing
account permissions

* msg deposit should validate that denoms are not equal

* add godoc comments

* golint and some poolName -> poolID cleanup

* implement adding liquidity to an existing pool

* hardcode pools in sims

* touch up comment

* withdraw keeper logic

* withdraw type updates

* add withdraw msg tx handler

* initial withdraw test

* fix panic

* use new denominated pool with existing shares

* fix: check args on deposit cmd

* add slippage limit check for depositing to an existing pool

* send coins just before event emission

* check liquidity returned is greater than zero for both coins; ensure
returned number of shares are greater than zero

* add deadline to msgwithdraw

* register msgwithdraw

* scaffold msgwithdraw types test

* register the correct msg

* modify swap functions to also return the amount paid for the pool swap
fee.  This will be used to calculate slippage and for event tracking

* add slippage types

* add expected withdrawal coins

* calculate slippage against expected coins

* update withdraw keeper tests

* spelling, improve comments on add liquidity math

* typo

* typo

* grammer

* typo / grammer

* remove pool_id from withdraw msg

* add slippage to tx cmd

* TestWithdraw_Partial

* nit

* add withdraw no pool, no deposit record tests

* drop event check on partial withdraw test

* fix broken link

* fix broken link

* resolve merge conflicts

* ensure swap fee can not be equal to 1; add full implementation of swap
pool methods;  these implementation ensure that the pool invariant is
always greater or equal to the previous invariant

* refactor duplicated code into private swap methods

* add runtime assertion to always ensure invariant is greater or equal
to the previous invariant sub fee on swaps

* improve comments for base pool swap functions

* add swap exact input and output methods to denominated pool that wrap
the base pool interface for swapping

* comment touch ups

* more comment touchups

* fix msg deposit struct tag (#943)

* use better name for swap calculation private methods

* nits: golint

* fix misspelling in method name

* Add HARD token governance committee for Hard module (#941)

* add hard gov token committee

* revisions: update migration

* revisions: update test/data file

* initial revisions

* add TokenCommittee JSONMarshal test

* fix SetPermissions method

* remove BaseCommittee Type field

* add incentive params to allowed params

* Add SWP token governance committee for Swap module (#946)

* add swp token commitee to migration

* update test, add gen export utility method

* final revisions: add TODO

* remove slippage from withdraw to use min values for coins; add
additional validation test cases

* update alias for swap module

* add withdraw tests to handler for increased coverage; note: first pass,
improvements still yet to be made here

* refact withdraw keeper to use min amounts; panic for cases that do not
happen in normal situations

* lint fixes

* use total shares to track if pool should be deleted; add more in depth
withdraw comment

* add exact args for withdraw cmd

* extract record update methods

* update depositor share record if it exists -- do not overwrite an
existing record; ensures no loss of shares if the same address deposits
more than once

* Swap queries: deposit, pool, pools (#949)

* query deposits types

* implement deposit querier keeper methods

* query deposits CLI

* query deposits REST

* query types for pool/pools

* pool/pools querier keeper methods

* pool/pools CLI

* pool/pools REST

* basic pool/pools query tests

* basic deposit querier test

* iterate share records via owner bytes

* nit: add example for querying deposits by owner only

Co-authored-by: karzak <kjydavis3@gmail.com>

* feat: add REST tx handler for swap LP withdrawals

Co-authored-by: Nick DeLuca <nickdeluca08@gmail.com>
Co-authored-by: Denali Marsh <denali@kava.io>
Co-authored-by: denalimarsh <denalimarsh@gmail.com>
Co-authored-by: karzak <kjydavis3@gmail.com>
2021-07-13 12:38:15 +01:00

146 lines
5.6 KiB
Go

package keeper
import (
"fmt"
sdk "github.com/cosmos/cosmos-sdk/types"
sdkerrors "github.com/cosmos/cosmos-sdk/types/errors"
"github.com/kava-labs/kava/x/swap/types"
)
// Deposit creates a new pool or adds liquidity to an existing pool. For a pool to be created, a pool
// for the coin denominations must not exist yet, and it must be allowed by the swap module parameters.
//
// When adding liquidity to an existing pool, the provided coins are considered to be the desired deposit
// amount, and the actual deposited coins may be less than or equal to the provided coins. A deposit
// will never be exceed the coinA and coinB amounts.
//
// The slippage is calculated using both the price and inverse price of the provided coinA and coinB.
// Since adding liquidity is not directional, like a swap would be, using both the price (coinB/coinA),
// and the inverse price (coinA/coinB), protects the depositor from a large deviation in their deposit.
//
// The amount deposited may only change by B' < B or A' < A -- either B depreciates, or A depreciates.
// Therefore, slippage can be written as a function of this depreciation d. Where the new price is
// B*(1-d)/A or A*(1-d)/B, and the inverse of each, and is A/(B*(1-d)) and B/(A*(1-d))
// respectively.
//
// Since 1/(1-d) >= (1-d) for d <= 1, the maximum slippage is always in the appreciating price
// A/(B*(1-d)) and B/(A*(1-d)). In other words, when the price of an asset depreciates, the
// inverse price -- or the price of the other pool asset, appreciates by a larger amount.
// It's this percent change we calculate and compare to the slippage limit provided.
//
// For example, if we have a pool with 100e6 ukava and 400e6 usdx. The ukava price is 4 usdx and the
// usdx price is 0.25 ukava. If a depositor adds liquidity of 4e6 ukava and 14e6 usdx, a kava price of
// 3.50 usdx and a usdx price of 0.29 ukava. This is a -12.5% slippage is the ukava price, and a 14.3%
// slippage in the usdx price.
//
// These slippages can be calculated by S_B = ((A/B')/(A/B) - 1) and S_A ((B/A')/(B/A) - 1), simplifying to
// S_B = (A/A' - 1), and S_B = (B/B' - 1). An error is returned when max(S_A, S_B) > slippageLimit.
func (k Keeper) Deposit(ctx sdk.Context, depositor sdk.AccAddress, coinA sdk.Coin, coinB sdk.Coin, slippageLimit sdk.Dec) error {
desiredAmount := sdk.NewCoins(coinA, coinB)
poolID := types.PoolIDFromCoins(desiredAmount)
poolRecord, found := k.GetPool(ctx, poolID)
var (
depositAmount sdk.Coins
shares sdk.Int
err error
)
if found {
depositAmount, shares, err = k.addLiquidityToPool(ctx, poolRecord, depositor, desiredAmount)
} else {
depositAmount, shares, err = k.initializePool(ctx, poolID, depositor, desiredAmount)
}
if err != nil {
return err
}
if depositAmount.AmountOf(coinA.Denom).IsZero() || depositAmount.AmountOf(coinB.Denom).IsZero() {
return sdkerrors.Wrap(types.ErrInsufficientLiquidity, "deposit must be increased")
}
if shares.IsZero() {
return sdkerrors.Wrap(types.ErrInsufficientLiquidity, "deposit must be increased")
}
maxPercentPriceChange := sdk.MaxDec(
desiredAmount.AmountOf(coinA.Denom).ToDec().Quo(depositAmount.AmountOf(coinA.Denom).ToDec()),
desiredAmount.AmountOf(coinB.Denom).ToDec().Quo(depositAmount.AmountOf(coinB.Denom).ToDec()),
)
slippage := maxPercentPriceChange.Sub(sdk.OneDec())
if slippage.GT(slippageLimit) {
return sdkerrors.Wrapf(types.ErrSlippageExceeded, "slippage %s > limit %s", slippage, slippageLimit)
}
err = k.supplyKeeper.SendCoinsFromAccountToModule(ctx, depositor, types.ModuleAccountName, depositAmount)
if err != nil {
return err
}
ctx.EventManager().EmitEvent(
sdk.NewEvent(
types.EventTypeSwapDeposit,
sdk.NewAttribute(types.AttributeKeyPoolID, poolID),
sdk.NewAttribute(types.AttributeKeyDepositor, depositor.String()),
sdk.NewAttribute(sdk.AttributeKeyAmount, depositAmount.String()),
sdk.NewAttribute(types.AttributeKeyShares, shares.String()),
),
)
return nil
}
func (k Keeper) depositAllowed(ctx sdk.Context, poolID string) bool {
params := k.GetParams(ctx)
for _, p := range params.AllowedPools {
if poolID == types.PoolID(p.TokenA, p.TokenB) {
return true
}
}
return false
}
func (k Keeper) initializePool(ctx sdk.Context, poolID string, depositor sdk.AccAddress, reserves sdk.Coins) (sdk.Coins, sdk.Int, error) {
if allowed := k.depositAllowed(ctx, poolID); !allowed {
return sdk.Coins{}, sdk.ZeroInt(), sdkerrors.Wrap(types.ErrNotAllowed, fmt.Sprintf("can not create pool '%s'", poolID))
}
pool, err := types.NewDenominatedPool(reserves)
if err != nil {
return sdk.Coins{}, sdk.ZeroInt(), err
}
poolRecord := types.NewPoolRecord(pool)
shareRecord := types.NewShareRecord(depositor, poolRecord.PoolID, pool.TotalShares())
k.SetPool(ctx, poolRecord)
k.SetDepositorShares(ctx, shareRecord)
return pool.Reserves(), pool.TotalShares(), nil
}
func (k Keeper) addLiquidityToPool(ctx sdk.Context, record types.PoolRecord, depositor sdk.AccAddress, desiredAmount sdk.Coins) (sdk.Coins, sdk.Int, error) {
pool, err := types.NewDenominatedPoolWithExistingShares(record.Reserves(), record.TotalShares)
if err != nil {
return sdk.Coins{}, sdk.ZeroInt(), err
}
depositAmount, shares := pool.AddLiquidity(desiredAmount)
poolRecord := types.NewPoolRecord(pool)
shareRecord, found := k.GetDepositorShares(ctx, depositor, poolRecord.PoolID)
if found {
shareRecord.SharesOwned = shareRecord.SharesOwned.Add(shares)
} else {
shareRecord = types.NewShareRecord(depositor, poolRecord.PoolID, shares)
}
k.SetPool(ctx, poolRecord)
k.SetDepositorShares(ctx, shareRecord)
return depositAmount, shares, nil
}