Perform swaps

This guide will walk you through how to perform swaps with Portal's Web SDK.

Please contact sales for additional pricing information on using the Swaps integrations at [e-mail]

Portal's Swaps integration allows you to easily extend your existing Portal instance with swaps functionality.

Fetching a list of Sources

The getSources() function returns an object containing valid, swappable token sources that can be used with your Portal MPC Wallet. The existing Portal instance that was provided at initialization is used to scope the request to the current chain.

In order to retrieve this list, you can use the following code.

const fetchSources = async (): Record<string, string> => {
    return await portal.getSources('YOUR_SWAPS_API_KEY', 'eip155:1')
}

The returned list

The object returned by the getSources() function is a set of key/value pairs where the key is the name of the token and the value is the token address for that token.

Fetching a swap Quote

The getQuote() function returns a Quote object for a given set of arguments.

QuoteArgs

The minimum requirements for a valid set of Quote arguments are a buyToken, a sellToken, and either a buyAmount or a sellAmount.

An example of a valid QuoteArgs object would look something like this.

import { QuoteArgs } from '@portal-hq/swaps'

const quoteArgs: QuoteArgs = {
    buyToken: 'UNI',
    sellToken: 'ETH',
    sellAmount: 1000, // Amount is in base units, so WEI for ETH
}

Using your QuoteArgs

Once you have a valid QuoteArgs object, you can call the getQuote() function.

const fetchQuote = async (quoteArgs: QuoteArgs): QuoteResponse {
    return await portal.getQuote('YOUR_SWAPS_API_KEY', quoteArgs, 'eip155:1')
}

The Quote object

The Quote object includes two properties:

• allowanceTarget The address requiring allowances to complete the Swap

• cost The total cost (gas fees) of the swap transaction

• transaction The transaction to perform the swap

Executing a Swap

If you're selling ERC20 tokens, you'll need to utilize the allowanceTarget to give the associated contract permissions to access a given amount of the token you're selling. This requires a token allowance of at least what you're selling. If you're selling ETH, this step is not necessary.

When you're ready to execute a swap, you can use the Provider on your existing Portal instance to sign the transaction and make a request to chain.

import { Eip1559, LegacyTx } from '@portal-hq/provider/types'

const executeSwap = async (transaction: Eip1559 | LegacyTx) => {
    const txHash = await portal.ethSendTransaction('eip155:1', transaction)
}