Requesting to Gate API v4 using Google Apps Script

submit.md

Requesting to Gate API v4 using Google Apps Script

This is a sample script for requesting to Gate API v4 using Google Apps Script.

The official document of Gate API v4 is here. Recently, I answered this thread. In that case, in order to convert the sample python script to Google Apps Script, the script for retrieving the signature might be a bit complicated. So, here, I would like to introduce this.

Sample python script from official document

This is a sample python script from official document.

import time
import hashlib
import hmac
import requests

def gen_sign(method, url, query_string=None, payload_string=None):
    key = ''        # api_key
    secret = ''     # api_secret

    t = time.time()
    m = hashlib.sha512()
    m.update((payload_string or "").encode('utf-8'))
    hashed_payload = m.hexdigest()
    s = '%s\n%s\n%s\n%s\n%s' % (method, url, query_string or "", hashed_payload, t)
    sign = hmac.new(secret.encode('utf-8'), s.encode('utf-8'), hashlib.sha512).hexdigest()
    return {'KEY': key, 'Timestamp': str(t), 'SIGN': sign}

host = "https://api.gateio.ws"
prefix = "/api/v4"
headers = {'Accept': 'application/json', 'Content-Type': 'application/json'}

url = '/wallet/total_balance'
query_param = ''
# for `gen_sign` implementation, refer to section `Authentication` above
sign_headers = gen_sign('GET', prefix + url, query_param)
headers.update(sign_headers)
r = requests.request('GET', host + prefix + url, headers=headers)
print(r.json())

In this post, this script is converted to Google Apps Script.

First, as the sample values, key, secret and t are sample, sample and 1234567890.123, respectively. When these values are used to the above script, the value of sign is 603899db07ca29e5240de397b8088271b765925ba29a67267b33ad0b076fc31b0cf98d623878d57bf824b58e5336fd74f1cd101e9377816c34fec2acb9358cb2.

Converted Google Apps Script from python script

When the above python script is converted to Google Apps Script, it becomes as follows.

function gen_sign_(
  key,
  secret,
  method,
  url,
  query_param = "",
  payload_string = ""
) {
  const t = (Date.now() / 1000).toString();
  const c1 = Utilities.computeDigest(
    Utilities.DigestAlgorithm.SHA_512,
    payload_string,
    Utilities.Charset.UTF_8
  );
  const c2 = Utilities.formatString(
    "%s\n%s\n%s\n%s\n%s",
    method,
    url,
    query_param,
    c1
      .map((b) => ("0" + ((b < 0 && b + 256) || b).toString(16)).slice(-2))
      .join(""),
    t
  );
  const c3 = Utilities.computeHmacSignature(
    Utilities.MacAlgorithm.HMAC_SHA_512,
    c2,
    secret,
    Utilities.Charset.UTF_8
  );
  const sign = c3
    .map((b) => ("0" + ((b < 0 && b + 256) || b).toString(16)).slice(-2))
    .join("");
  return { KEY: key, Timestamp: t, SIGN: sign };
}

// Please run this function.
function main() {
  const key = "your api key";
  const secret = "your secret";

  const host = "https://api.gateio.ws";
  const prefix = "/api/v4";
  const url = "/wallet/total_balance";
  const method = "GET";

  const signature = gen_sign_(key, secret, method, prefix + url);
  const headers = {
    Accept: "application/json",
    "Content-Type": "application/json",
    muteHttpExceptions: true,
    ...signature,
  };
  const res = UrlFetchApp.fetch(host + prefix + url, { method, headers });
  console.log(res.getContentText());
}

Here, as the sample values, key, secret and t are sample, sample and 1234567890.123, respectively. The value of sign is 603899db07ca29e5240de397b8088271b765925ba29a67267b33ad0b076fc31b0cf98d623878d57bf824b58e5336fd74f1cd101e9377816c34fec2acb9358cb2. By this, it can be confirmed that both values of sign are the same between the python script and the Google Apps Script.

Reference

• I answered this script to this thread at Stackoverflow.