init

store/gasPrices.js

@@ -0,0 +1,191 @@
+/* eslint-disable no-console */
+import { GasPriceOracle } from 'gas-price-oracle'
+import { toHex, toWei, toBN, fromWei } from 'web3-utils'
+
+export const state = () => {
+  return {
+    oracle: {
+      instant: 80,
+      fast: 50,
+      standard: 25,
+      low: 8
+    },
+    eip: {
+      instant: {
+        baseFee: 80,
+        maxFeePerGas: 80,
+        maxPriorityFeePerGas: 3
+      },
+      fast: {
+        baseFee: 50,
+        maxFeePerGas: 50,
+        maxPriorityFeePerGas: 3
+      },
+      standard: {
+        baseFee: 25,
+        maxFeePerGas: 27,
+        maxPriorityFeePerGas: 2
+      },
+      low: {
+        baseFee: 8,
+        maxFeePerGas: 9,
+        maxPriorityFeePerGas: 1
+      }
+    }
+  }
+}
+
+export const getters = {
+  oracle: (state, getters, rootState, rootGetters) => {
+    const netId = Number(rootGetters['metamask/netId'])
+    const { gasPrices } = rootGetters['metamask/networkConfig']
+
+    return new GasPriceOracle({
+      chainId: netId,
+      defaultRpc: rootGetters['settings/currentRpc'].url,
+      defaultFallbackGasPrices: gasPrices
+    })
+  },
+  eipSupported: (state, getters, rootState, rootGetters) => {
+    const netId = rootGetters['metamask/netId']
+    const networksWithEIP1559 = [1, 5]
+
+    return networksWithEIP1559.includes(netId)
+  },
+  getGasParams: (state, getters) => (speed = 'fast', isDisable = false) => {
+    const { maxFeePerGas, maxPriorityFeePerGas } = state.eip[speed]
+
+    if (!isDisable && getters.eipSupported) {
+      return {
+        maxFeePerGas: toHex(maxFeePerGas),
+        maxPriorityFeePerGas: toHex(maxPriorityFeePerGas)
+      }
+    }
+
+    return {
+      gasPrice: getters.getGasPrice(speed)
+    }
+  },
+  getGasPrice: (state, getters) => (speed = 'fast') => {
+    const gasPrices = getters.gasPrices
+    return toHex(toWei(gasPrices[speed].toString(), 'gwei'))
+  },
+  fastGasPrice: (state, getters) => {
+    return getters.getGasPrice('fast')
+  },
+  gasPrices: (state, getters) => {
+    const parseGwei = (value) => String(Math.floor(Number(fromWei(String(value), 'gwei')) * 100) / 100)
+
+    const { eip, oracle } = state
+
+    if (getters.eipSupported) {
+      return {
+        instant: parseGwei(eip.instant.maxFeePerGas),
+        low: parseGwei(eip.low.maxFeePerGas),
+        standard: parseGwei(eip.standard.maxFeePerGas),
+        fast: parseGwei(eip.fast.maxFeePerGas)
+      }
+    }
+
+    return {
+      instant: String(oracle.instant),
+      low: String(oracle.low),
+      standard: String(oracle.standard),
+      fast: String(oracle.fast)
+    }
+  }
+}
+
+export const mutations = {
+  SAVE_ORACLE_GAS_PRICES(state, { instant, fast, standard, low }) {
+    this._vm.$set(state.oracle, 'instant', instant)
+    this._vm.$set(state.oracle, 'fast', fast)
+    this._vm.$set(state.oracle, 'standard', standard)
+    this._vm.$set(state.oracle, 'low', low)
+  },
+  SAVE_EIP_GAS_PRICES(state, { instant, fast, standard, low }) {
+    this._vm.$set(state.eip, 'instant', instant)
+    this._vm.$set(state.eip, 'fast', fast)
+    this._vm.$set(state.eip, 'standard', standard)
+    this._vm.$set(state.eip, 'low', low)
+  }
+}
+
+export const actions = {
+  async fetchGasPrice({ getters, commit, dispatch, rootGetters, state }) {
+    const { pollInterval } = rootGetters['metamask/networkConfig']
+
+    try {
+      if (getters.eipSupported) {
+        const result = await dispatch('estimateFees')
+        commit('SAVE_EIP_GAS_PRICES', result)
+      } else {
+        const gas = await dispatch('getGasPrice')
+        commit('SAVE_ORACLE_GAS_PRICES', gas)
+      }
+
+      setTimeout(() => dispatch('fetchGasPrice'), 1000 * pollInterval)
+    } catch (e) {
+      console.error('fetchGasPrice', e)
+      setTimeout(() => dispatch('fetchGasPrice'), 1000 * pollInterval)
+    }
+  },
+  async estimateFees({ rootGetters }) {
+    try {
+      const { url } = rootGetters['settings/currentRpc']
+      const web3 = this.$provider.getWeb3(url)
+      const latestBlock = await web3.eth.getBlock('latest')
+
+      if (!latestBlock.baseFeePerGas) {
+        throw new Error('An error occurred while fetching current base fee, falling back')
+      }
+
+      const baseFee = toBN(latestBlock.baseFeePerGas)
+
+      const potentialMaxFee = baseFee.mul(toBN(1125)).div(toBN(1000))
+
+      const GWEI = (amount) => toBN(toWei(amount, 'gwei'))
+
+      const fastPriorityFee = GWEI('4')
+      const standardPriorityFee = GWEI('2.5')
+      const lowPriorityFee = GWEI('1')
+
+      return {
+        instant: {
+          baseFee,
+          maxFeePerGas: potentialMaxFee.add(fastPriorityFee),
+          maxPriorityFeePerGas: fastPriorityFee
+        },
+        fast: {
+          baseFee,
+          maxFeePerGas: potentialMaxFee.add(fastPriorityFee),
+          maxPriorityFeePerGas: fastPriorityFee
+        },
+        standard: {
+          baseFee,
+          maxFeePerGas: potentialMaxFee.add(standardPriorityFee),
+          maxPriorityFeePerGas: standardPriorityFee
+        },
+        low: {
+          baseFee,
+          maxFeePerGas: potentialMaxFee.add(lowPriorityFee),
+          maxPriorityFeePerGas: lowPriorityFee
+        }
+      }
+    } catch (err) {
+      throw new Error(err.message)
+    }
+  },
+  async getGasPrice({ state, getters }) {
+    try {
+      const gas = await getters.oracle.gasPrices(state.oracle)
+      return gas
+    } catch (err) {
+      throw new Error(err.message)
+    }
+  },
+  setDefault({ commit, rootGetters }) {
+    const { gasPrices } = rootGetters['metamask/networkConfig']
+    commit('SAVE_ORACLE_GAS_PRICES', gasPrices)
+  }
+}