10 Uniswap V3 怎么通过lp-NFT tokenId 查询当前可以兑换出多少数量的token0 和token1,uniswapV3的前端移除流动性前是有对应token数量显示的

Uniswap V3 怎么通过lp-NFT tokenId 查询当前可以兑换出多少数量的token0 和token1,uniswapV3的前端移除流动性前是有对应token数量显示的,看Pool合约代码有一个_modifyPosition私有接口来计算对应数量和修改position的数据

/// @dev Effect some changes to a position
    /// @param params the position details and the change to the position's liquidity to effect
    /// @return position a storage pointer referencing the position with the given owner and tick range
    /// @return amount0 the amount of token0 owed to the pool, negative if the pool should pay the recipient
    /// @return amount the amount of token1 owed to the pool, negative if the pool should pay the recipient
    function _modifyPosition(ModifyPositionParams memory params)
        private
        noDelegateCall
        returns (
            Position.Info storage position,
            int256 amount0,
            int256 amount1
        )
    {
        checkTicks(params.tickLower, params.tickUpper);

        Slot0 memory _slot0 = slot0; // SLOAD for gas optimization

        position = _updatePosition(
            params.owner,
            params.tickLower,
            params.tickUpper,
            params.liquidityDelta,
            _slot0.tick
        );

        if (params.liquidityDelta != 0) {
            if (_slot0.tick < params.tickLower) {
                // current tick is below the passed range; liquidity can only become in range by crossing from left to
                // right, when we'll need _more_ token0 (it's becoming more valuable) so user must provide it
                amount0 = SqrtPriceMath.getAmount0Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
            } else if (_slot0.tick < params.tickUpper) {
                // current tick is inside the passed range
                uint128 liquidityBefore = liquidity; // SLOAD for gas optimization

                // write an oracle entry
                (slot0.observationIndex, slot0.observationCardinality) = observations.write(
                    _slot0.observationIndex,
                    _blockTimestamp(),
                    _slot0.tick,
                    liquidityBefore,
                    _slot0.observationCardinality,
                    _slot0.observationCardinalityNext
                );

                amount0 = SqrtPriceMath.getAmount0Delta(
                    _slot0.sqrtPriceX96,
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
                amount1 = SqrtPriceMath.getAmount1Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    _slot0.sqrtPriceX96,
                    params.liquidityDelta
                );

                liquidity = LiquidityMath.addDelta(liquidityBefore, params.liquidityDelta);
            } else {
                // current tick is above the passed range; liquidity can only become in range by crossing from right to
                // left, when we'll need _more_ token1 (it's becoming more valuable) so user must provide it
                amount1 = SqrtPriceMath.getAmount1Delta(
                    TickMath.getSqrtRatioAtTick(params.tickLower),
                    TickMath.getSqrtRatioAtTick(params.tickUpper),
                    params.liquidityDelta
                );
            }
        }
    }
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最佳答案 2022-02-19 14:49

一个节省 gas 的方法是:

通过项目方签名授权的方式在链下控制白名单。

v3-periphery 的 PositionValue 提供了方法: principal 用来获取 两个token 的数量。

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Alan
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  • Ethereal 提出于 2022-02-15 11:50