@cowprotocol/cow-sdk

CoW SDK

Getting started

Install the SDK:

yarn add @cowprotocol/cow-sdk

Instantiate the SDK:

import { CowSdk } from '@cowprotocol/cow-sdk'

const chainId = 4 // Rinkeby
const cowSdk = new CowSdk(chainId)

The SDK will expose:

• The CoW API (cowSdk.cowApi)
• The CoW Subgraph (cowSdk.cowSubgraphApi)
• Convenient method to facilitate signing orders (i.e cowSdk.signOrder)

For a quick snippet with the full process on posting an order see the Post an Order Example

CoW API

The SDK provides access to the CoW API. The CoW API allows you:

• Post orders
• Get fee quotes
• Get order details
• Get history of orders: i.e. filtering by account, transaction hash, etc.

For example, you can easily get the last 5 order of a trader:

// i.e. Get last 5 orders for a given trader
const trades = await cowSdk.cowApi.getOrders({
  owner: '0x00000000005ef87f8ca7014309ece7260bbcdaeb', // Trader
  limit: 5,
  offset: 0,
})
console.log(trades)

For more information about the API methods, you can check api.cow.fi/docs.

Sign and Post orders

In order to trade, you will need to create a valid order first.

On the contraty to other decentralised exchanges, creating orders is free in CoW Protocol. This is because, one of the most common ways to do it is by created offchain signed messages (meta-transactions, uses EIP-712 or EIP-1271).

Posting orders is a three steps process:

• 1. Get Market Pricea: Fee & Price
• 1. Sign the order: Using off-chain signing or Meta-transactions
• 1. Post the signed order to the API: So, the order becomes OPEN

The next sections will guide you through the process of creating a valid order.

For a quick snippet with the full process on posting an order see the Post an Order Example.

Enable tokens (token approval)

Because of the use of off-chain signing (meta-transactions), users will need to Enable the sell token before signed orders can be considered as valid ones.

This enabling is technically an ERC-20 approval, and is something that needs to be done only once. After this all order creation can be done for free using offchain signing.

For more details see https://docs.cow.fi/tutorials/how-to-submit-orders-via-the-api/1.-set-allowance-for-the-sell-token

Instantiate SDK with a signer

Before you can sign any transaction, you have to instantiate the SDK with a Ethers.JS signer:

import { Wallet } from 'ethers'
import { CowSdk, OrderKind } from '@cowprotocol/cow-sdk'

const mnemonic = 'fall dirt bread cactus...'
const wallet = Wallet.fromMnemonic(mnemonic)
const cowSdk = new CowSdk(
  4, {            // Leaving chainId empty will default to MAINNET
  signer: wallet  // Provide a signer, so you can sign order
  }) 

STEP 1: Get Market Price

To create an order, you need to get a price/fee quote first:

• The SDK will give you easy access to the API, which returns the Market Price and the Fee for any given trade you intent to do.
• The returned Market Price is not strictly needed, you can use your own pricing logic.
  • You can choose a price that is below this Market price (Market Order), or above Market Price (Limit Order).
• The Fee however is very important.
  • It is the required amount in sell token the trader agrees on paying for executing the order onchain.
  • Normally, its value is proportional to the current Gas Price of the network.
  • This fee is never charged if you don't trade.

To get the quote, you simply specify the trade you intent to do:

const quoteResponse = await cowSdk.cowApi.getQuote({
  kind: OrderKind.SELL, // Sell order (could also be BUY)
  sellToken: '0xc778417e063141139fce010982780140aa0cd5ab', // WETH
  buyToken: '0x4dbcdf9b62e891a7cec5a2568c3f4faf9e8abe2b', // USDC
  amount: '1000000000000000000', // 1 WETH
  userAddress: '0x1811be0994930fe9480eaede25165608b093ad7a', // Trader
  validTo: 2524608000,
})

const { sellToken, buyToken, validTo, buyAmount, sellAmount, receiver, feeAmount } = quoteResponse.quote

STEP 2: Sign the order

Once you know the price and fee, we can create the order and sign it:

• Technically the order is just a signed message with your intent to trade, and contains your Limit Price and Fee.
• As explained before, you can choose your Limit Price, but some general approach is to take the current Market Price and apply some slippage tolerance to it. Received Amount = Expected Amount * (1 - Slippage Tolerance)
• The SDK will provide an easy way to sign orders given the raw data

const { sellToken, buyToken, validTo, buyAmount, sellAmount, receiver, feeAmount } = quoteResponse.quote

// Prepare the RAW order
const order = {
  kind: OrderKind.SELL, // SELL || BUY  
  receiver, // Your account or any other
  sellToken,
  buyToken,

  partiallyFillable: false, // ("false" is for a "Fill or Kill" order, "true" for allowing "Partial execution" which is not supported yet)

  // Deadline
  validTo,

  // Limit Price
  //    You can apply some slippage tolerance here to make sure the trade is executed. 
  //    CoW protocol protects from MEV, so it can work with higher slippages
  sellAmount,
  buyAmount, 

  // Use the fee you received from the API
  feeAmount,

  // The appData allows you to attach arbitrary information (meta-data) to the order. Its explained in their own section. For now, you can use this 0x0 value
  appData: '0x0000000000000000000000000000000000000000000000000000000000000000'
}

// Sign the order
const signedOrder = await cowSdk.signOrder(order)

At this point, you have a signed order. So next step will be to post it to the API so it's considered by the solvers and executed.

STEP 3: Post the signed order to the API:

Once you have a signed order, last step is to send it to the API.

• The API will accept the order if its correctly signed, the deadline is correct, and the fee is enough to settle it
• Once accepted, the order will be OPEN until the specified validTo date (expiration)
• The possible outcomes once accepted is:
  • The order is EXECUTED: you will pay the signed fee, and get at least the buyAmount tokens you specified, although you will probably get more! (you will probably get a so-called Surplus).
  • The order EXPIRES: If your price is not good enough, and the order is out of the market price before expiration, your order will expire. This doesn't have any cost to the user, which only pays the fee if the trade is executed.
  • You cancel the order, so it becomes CANCELLED. Cancelling an order can be done both as a free meta-transaction (soft cancelations) or as a regular on-chain transaction (hard cancelations).
• The API will return an orderId which identifies the order, and is created as a summary (hash) of it. In other words, the orderId is deterministic given all the order parameters.

Post an order using the SDK:

const orderId = await cowSdk.cowApi.sendOrder({
  order: { ...order, ...signedOrder },
  owner: '0x1811be0994930fe9480eaede25165608b093ad7a',
})

BONUS: Show link to Explorer

Once the order is posted, its good to allow to check the state of it.

One easy is to check in the CoW Explorer. You can create a CoW Explorer link if you have the orderId:

// View order in explorer
console.log(`https://explorer.cow.fi/rinkeby/orders/${orderId}`)

Create a meta-data document for attaching to an order

Orders in CoW Protocol can contain arbitrary data in a field called AppData.

The SDK facilitates the creation of these documents, and getting the AppData Hex number that summarizes it.

The most important thing to define in the meta-data is the name of your app, so the order-flow can be credited to it.

const appDataDoc = cowSdk.metadataApi.generateAppDataDoc({
  appDataParams: { appCode: "YourApp" }
})

This will create a document similar to:

{
  "version": "0.4.0",
  "appCode": "YourApp",
  "metadata": {}
} 

After creating the most basic document, you can see how to attach additional meta-data items.

For example, you could give information about who referred the user creating the order.

const appDataDoc = cowSdk.metadataApi.generateAppDataDoc({
  appDataParams: { appCode: "YourApp" },
  metadataParas: {
    referrerParams: {
      address: '0x1f5B740436Fc5935622e92aa3b46818906F416E9'
    }
  }
})

This will create a document similar to:

{
  "version": "0.4.0",
  "appCode": "YourApp",
  "metadata": {
    "referrer": {
      "address": "0x1f5B740436Fc5935622e92aa3b46818906F416E9",
      "version": "0.1.0"
    }
  }
}

The method cowSdk.metadataApi.generateAppDataDoc will always create the latest schema version.

For a complete list of metadata that can be attached and for previous versions check @cowprotocol/app-data repository and NPM package

Get the AppData Hex

The AppData Hex points to an IPFS document with the meta-data attached to the order.

You can calculate the AppData Hex, and its corresponding cidV0 using the SDK:

const { appDataHash, cidv0 } = await cowSdk.metadataApi.calculateAppDataHash(appDataDoc)

Note how this operation is deterministic, so given the same document, it will always generate the same hash.

This method can be used to calculate the actual hash before uploading the document to IPFS.

Get meta-data document uploaded to IPFS from AppData

Given the AppData of a document that has been uploaded to IPFS, you can easily retrieve the document.

const appDataDoc = await cowSdk.metadataApi.decodeAppData('0x5ddb2c8207c10b96fac92cb934ef9ba004bc007a073c9e5b13edc422f209ed80')

This will return a document similar to:

{
  "version": "0.1.0",
  "appCode": "YourApp",
  "metadata": {
    "referrer": {
      "address": "0x1f5B740436Fc5935622e92aa3b46818906F416E9",
      "version": "0.1.0"
    }
  }
}

Upload document to IPFS

The SDK uses Pinata to upload it to IPFS, so you will need an API Key in order to upload it using the SDK.

Alternatively, you can upload the document on your own using any other service.

// Make sure you provide the IPFS params when instantiating the SDK
const cowSdk = new CowSdk(4, {
  ipfs: { 
    pinataApiKey: 'YOUR_PINATA_API_KEY', 
    pinataApiSecret: 'YOUR_PINATA_API_SECRET'
  },
})

// Upload to IPFS
const uploadedAppDataHash = await cowSdk.metadataApi.uploadMetadataDocToIpfs(appDataDoc)

Convert IPFS CIDv0 to AppData (and back)

Given an IPFS CIDv0 you can convert it to an AppData

const decodedAppDataHex = await cowSdk.metadataApi.cidToAppDataHex('QmUf2TrpSANVXdgcYfAAACe6kg551cY3rAemB7xfEMjYvs')

This will return an AppData hex: 0x5ddb2c8207c10b96fac92cb934ef9ba004bc007a073c9e5b13edc422f209ed80

This might be handy if you decide to upload the document to IPFS yourself and then you need the AppData to post your order

Similarly, you can do the opposite and convert an AppData into an IPFS document:

const decodedAppDataHex = await cowSdk.metadataApi.appDataHexToCid(hash)

This will return an IPFS CIDv0: QmUf2TrpSANVXdgcYfAAACe6kg551cY3rAemB7xfEMjYvs

Getting appData schema files

It's possible to get schema files directly for each exported version using getAppDataSchema

const schema = await cowSdk.metadataApi.getAppDataSchema('0.4.0')

Validating appDataDocs

If for some reason you decide to create an appDataDoc without using the helper function, you can use validateAppDataDoc to validate it against the schema

const { success, error } = await cowSdk.metadataApi.validateAppDataDoc({ version: '0.1.0', ... })

Querying the Cow Subgraph

You can query the Cow Subgraph either by running some common queries exposed by the CowSubgraphApi or by building your own ones:

const chainId = 1 // Mainnet
const cowSdk = new CowSdk(chainId)

// Get Cow Protocol totals
const { tokens, orders, traders, settlements, volumeUsd, volumeEth, feesUsd, feesEth } =
  await cowSdk.cowSubgraphApi.getTotals()
console.log({ tokens, orders, traders, settlements, volumeUsd, volumeEth, feesUsd, feesEth })

// Get last 24 hours volume in usd
const { hourlyTotals } = await cowSdk.cowSubgraphApi.getLastHoursVolume(24)
console.log(hourlyTotals)

// Get last week volume in usd
const { dailyTotals } = await cowSdk.cowSubgraphApi.getLastDaysVolume(7)
console.log(dailyTotals)

// Get the last 5 batches
const query = `
  query LastBatches($n: Int!) {
    settlements(orderBy: firstTradeTimestamp, orderDirection: desc, first: $n) {
      txHash
      firstTradeTimestamp
    }
  }
`
const variables = { n: 5 }
const response = await cowSdk.cowSubgraphApi.runQuery(query, variables)
console.log(response)

Install Dependencies

yarn

Build

yarn build

# Build in watch mode
yarn start

Unit testing

yarn test