Execute Swaps

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async approve(approveContract) {
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  let approve = await swapSdk.approve({
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    chain: this.chainName,
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    tokenAddress: this.inToken.address,
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    approveContract: approveContract,
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    gasPrice: this.gasPrice,
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    decimals: this.inToken.decimals,
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    amount: this.inAmount
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  })
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  if (!approve.code) {
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    approve
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      .on('error', (error) => { console.error(error) })
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      .on('transactionHash', (hash) => { console.log('Approval tx:', hash) })
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      .on('receipt', (data) => { console.log('Approved') })
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      .on('success', (data) => { console.log('Success') })
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  }
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}

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async swap() {
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  if (!this.myWallet) {
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    alert('Please connect the wallet.')
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    return
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  }
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  if (this.inTokenBalance < this.inAmount) {
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    alert(this.inToken.symbol + ' Insufficient balance.')
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    return
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  }
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  // Get exchange info for approve contract
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  let { data } = await api.exchange({ chain: this.chainName })
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  // Check allowance
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  let allowance = await this.getAllowance(data.approveContract)
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  if (new BigNumber(allowance).lt(this.inAmount)) {
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    await this.approve(data.approveContract)
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    return
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  }
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  // Get swap quote with account
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  let response = await swapSdk.swapQuote({
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    chain: this.chainName,
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    inTokenAddress: this.inToken.address,
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    outTokenAddress: this.outToken.address,
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    amount: this.inAmount,
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    gasPrice: this.gasPrice,
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    slippage: 1,
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    account: this.myWallet.address,
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  })
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  if (response.code == 200) {
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    swapSdk.swap(response.data)
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      .on('error', (error) => { console.error(error) })
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      .on('transactionHash', (hash) => { console.log('Swap tx:', hash) })
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      .on('receipt', (data) => { this.getBalance() })
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      .on('success', (data) => { console.log('Swap complete') })
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  } else {
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    alert('Error:' + response.message)
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  }
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}

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async getAllowance(approveContract) {
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  return await swapSdk.getAllowance({
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    chain: this.chainName,
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    decimals: this.inToken.decimals,
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    tokenAddress: this.inToken.address,
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    approveContract,
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    account: this.myWallet.address
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  })
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}