<a name="table-of-contents"></a>

## Table of contents

- [Get Started](#get-started)
- [API Authentication](#api-authentication)
- [Create Auth Token Via Playground](#create-auth-token-via-playground)
- [Create Auth Token Yourself](#create-auth-token-yourself)
- [Playground API](#playground-api)
- [Generate Fiat Purchase Crypto PaymentUrl](#generate-fiat-purchase-crypto-paymentUrl)
- [Fetch Generic Spot Price and different payment method price](#fetch-generic-spot-price-and-different-payment-method-price)
- [Get Supporting Fiats](#get-spupporting-fiats)
- [Get Supporting Coins and its support chains](#get-supporting-coins-and-its-support-chains)

# Get Started

Onboarding Process

1. Contact Gim.Cool Sales for an API key and API secret for Sandbox Environment.

2. Using Gim.Cool Playground for API Integration

3. Submit Ready-to-use product to Gim.Cool Sales for Reviewing.

4. Gim.Cool Sales will provide you with an API key and API secret for Production Environment.

# Create Auth Token Via Playground

1. Visit [Graphql Playground](https://www.gimcool.io/api/banxa)

2. Enter your API key and API secret in the query parameters.

## Generate Auth Token
query generateAuthToken {
  public {
    generateHMACAuthorizationCode(
      input: {
        apiKey: "YOUR_API_KEY"
        apiSecret: "YOUR_API_SECRET"
        method: "POST"
        path: "/api/banxa"
        unixTimestamp: "1658736099" # Using Current Unix Timestamp
      }
    ) {
      authorizationHeader
    }
  }
}

3. Append the Authorization Header to the request headers for accessing every api request.

### Create Auth Token Yourself

For all requests to the GimCool API, add an Authorization digest to the header. The header structure must be in the following format:

"Authorization: Bearer API Key:Signature:Nonce"

#### API Key

The API public key credential. This is the one provided by us during on-boarding.

#### Signature

Message authentication signature. The request message is hashed with the API Secret using SHA256 algorithm.

The structure of the message:

- Request method. (e.g. "GET or "POST")
- Request URI path including the query parameters for GET.
- The nonce value (e.g. using unix timestamp value)

#### Nonce

A unix timestamp in milliseconds generated for this request.

## Sample Code

Here is some sample code around how to call the API including the HMAC authentication. Key things to note when building your integration:

- The signature passed to the HMAC algorithm are separated by new lines (see above section)
- The json payload for POST requests should contain no whitespace
- The nonce should be a unix timestamp which is generated for every request

const crypto = require('crypto');
const moment = require('moment');
const YOUR_API_SECRET = 'YOUR_API_SECRET';
const YOUR_API_KEY = 'YOUR_API_KEY';
const unixTimestamp = moment().unix();

const signature = crypto
  .createHmac('SHA256', params.secret)
  .update(
    JSON.stringify({
      path: '/api/banxa',
      method: 'POST',
      unixTimestamp: unixTimestamp,
    })
  )
  .digest('hex');

const YOUR_AUTHORIZATION_HEADER = `Bearer ${YOUR_API_KEY}:${signature}:${unixTimestamp}`;

### Start making requests

const YOUR_AUTHORIZATION_HEADER = `Bearer ...`;
const graphqlRequest = require('graphql-request');
const { request, gql } = graphqlRequest;
const endpoint = 'https://gimcool.io/api/banxa';
const client = new graphqlRequest.GraphQLClient(endpoint, {
  headers: {
    Authorization: YOUR_AUTHORIZATION_HEADER,
  },
});

const query = gql`
  query generateFiatPurchaseCryptoPaymentUrl {
    fiatPurchaseCryptoPaymentInfo(
      input: {
        coinType: "USDT"
        fiatType: "USD"
        coinAmount: "500"
        blockchain: "ETH"
        walletAddress: "0x8335f5D820c39baD7f3D39eDd0658E1941848948"
      }
    ) {
      paymentHref
    }
  }
`;

request(query).then((data) => console.log(data));

# Playground API

### Generate Fiat Purchase Crypto PaymentUrl

Request

query generateFiatPurchaseCryptoPaymentUrl {
  fiatPurchaseCryptoPaymentInfo(
    input: {
      coinType: "USDT"
      fiatType: "USD"
      coinAmount: "500"
      blockchain: "ETH"
      walletAddress: "0x8335f5D820c39baD7f3D39eDd0658E1941848948"
    }
  ) {
    paymentHref
  }
}

Response

{
  "data": {
    "fiatPurchaseCryptoPaymentInfo": {
      "paymentHref": "https://gimcool.io/purchase/?blockchain=ETH&coinAmount=500&coinType=USDT&fiatAmount&fiatType=USD&walletAddress=0x8335f5D820c39baD7f3D39eDd0658E1941848948"
    }
  }
}

### Get Supporting Coins and its support chains

Request

query getSupportCoins {
  coins {
    coinCode
    coinName
    blockchains {
      code
      description
      isDefault
    }
  }
}

Response

{
  "data": {
    "coins": [
      {
        "coinCode": "BTC",
        "coinName": "Bitcoin",
        "blockchains": [
          {
            "code": "BTC",
            "description": "Bitcoin",
            "isDefault": true
          }
        ]
      },
      {
        "coinCode": "ETH",
        "coinName": "Ethereum",
        "blockchains": [
          {
            "code": "ETH",
            "description": "Ethereum (ERC-20)",
            "isDefault": true
          }
        ]
      },
      {
        "coinCode": "USDT",
        "coinName": "Tether",
        "blockchains": [
          {
            "code": "ETH",
            "description": "Ethereum (ERC-20)",
            "isDefault": true
          }
        ]
      },
      {
        "coinCode": "BUSD",
        "coinName": "BinanceUSD",
        "blockchains": [
          {
            "code": "ETH",
            "description": "Ethereum (ERC-20)",
            "isDefault": true
          }
        ]
      }
      // ... more
    ]
  }
}

### Get Supporting Fiats

Request

query getSupportFiats {
  fiats {
    fiatCode
    fiatName
    fiatSymbol
  }
}

Response

{
  "data": {
    "fiats": [
      {
        "fiatCode": "TWD",
        "fiatName": "New Taiwan Dollar",
        "fiatSymbol": "NT$"
      },
      {
        "fiatCode": "USD",
        "fiatName": "US Dollar",
        "fiatSymbol": "$"
      }
      // ...more
    ]
  }
}

### Fetch Generic Spot Price and different payment method price

Request

query fetchPriceAndPaymentMethods($source: String! = "USD", $target: String! = "BTC") {
  fetchPrice(input: { source: $source, target: $target }) {
    spotPrice
    prices {
      paymentMethodId
      type
      spotPriceFee
      spotPriceIncludingFee
      coinAmount
      coinCode
      networkFee
      fiatAmount
      fiatCode
    }
  }
  paymentMethods(input: { source: $source, target: $target }) {
    id
    name
  }
}

Response

{
  "data": {
    "fetchPrice": {
      "spotPrice": "22131.06",
      "prices": [
        {
          "paymentMethodId": "7536",
          "type": "FIAT_TO_CRYPTO",
          "spotPriceFee": "0.00",
          "spotPriceIncludingFee": "22131.06",
          "coinAmount": "1.00000000",
          "coinCode": "BTC",
          "networkFee": "0.00",
          "fiatAmount": "22131.06",
          "fiatCode": "USD"
        }
        // ... more
      ]
    },
    "paymentMethods": [
      {
        "id": "6039",
        "name": "Apple Pay"
      }
      // ... more
    ]
  }
}