Module 1 - PathFinder API Flow

PathFinder API Architecture

Follow this Repository to see the Code of the dApp we’re Building.

Step 1: Get the Quote

Step 2: Check and Set Allowance

Step 3: Execute the Transaction

Untitled Workspace

Step1: Get the Quote

Router Nitro enables you to Interact with the Nitro Contract and initiate cross-chain Token Transfers. The First Step in this Process is to Request a Quote, which provides you with Essential Details about the Proposed Token Transfer.

To Request a Quote, follow these Steps:

Define the PATH_FINDER_API_URL: Set the PATH_FINDER_API_URL Variable to the URL of the Pathfinder API for the Voyager Testnet. This is where you will send your Quote Request.
```
const PATH_FINDER_API_URL = "https://api.pf.testnet.routerprotocol.com/api";
```

Create the getQuote Function: This Function handles the Quote Request. It uses the axios Library to make an HTTP GET Request to the Voyager Pathfinder API.

const getQuote = async (params) => {
  const endpoint = "v2/quote";
  const quoteUrl = `${PATH_FINDER_API_URL}/${endpoint}`;
  try {
    const res = await axios.get(quoteUrl, { params });
    return res.data;
  } catch (e) {
    console.error(`Fetching quote data from pathfinder: ${e}`);
  }
};

Call the getQuote Function: Use this Function to Request a Quote by passing appropriate Parameters. In this Repository, this Function is called using a button.
```
// Example usage:
const quoteParams = {
fromTokenAddress: from,
toTokenAddress: to,
amount: amount,
fromTokenChainId: "80001",
toTokenChainId: "43113", // Fuji

widgetId: 0,
};

const quoteData = await getQuote(quoteParams);
console.log("Quote Data:", quoteData);
```
These Parameters Define the Details of the Token Transfer you wish to Execute. Let’s Break down what each Parameter represents:
- 'fromTokenAddress': This should specify the address of the Token you want to Transfer from (the Source Token).
- 'toTokenAddress': Provide the Address of the Token you want to Transfer to (the Dstination Token).
- 'amount': Set the Amount of the Token you wish to Transfer.
- 'fromTokenChainId': This Parameter Represents the Chain ID of the Source Blockchain. In this Case, it’s Set to “80001.”
- 'toTokenChainId': Similarly, this Parameter Specifies the Chain ID of the Destination Blockchain, which, in this example, is “43113” (Fuji).
- 'widgetId': This Parameter is used to identify the Widget Responsible for the Transfer. For now, Keep it as 0.
With these Parameters, you can now Call the getQuote Function with this params Object to initiate a Quote Request for your Specific Token Transfer.

Response

The getQuote Function returns the Quote Data, which typically includes Details about the Token Transfer, such as Source and Destination Chains, Token Amount, Fees, and other Relevant Information. Click the Get Quote Button and go to console to see the Quote Data printed on console.