Sumsub SDK Integration Guide

Overview

This document explains how the Sumsub WebSDK is integrated into the dashboard onboarding flow to enable customer KYC/KYB verification within the application.

Backend Setup

Base URLs

Production

https://api.relm.co/v1

Sandbox

https://sandbox.api.relm.co/v1

API Authentication

All API requests must be authenticated using a signature-based authentication mechanism.

To generate the signature, you will need the following credentials:

  • Key ID
  • Public Key
  • Private Key

The generated signature must be included in the request headers when calling any RELM API.

Generating the API Signature

Use your Key ID, Public Key, and Private Key to generate the authentication signature as described in the documentation below.

Signature Generation Guide

Retrieve API Credentials

The following credentials are required to generate the API signature:

  • Key ID
  • Public Key
  • Private Key

These credentials will be shared with you through secure links.

⚠️ Important:
Each secure link can be opened only once. Please make sure to store the credentials in a secure location after accessing them.

Access Token API

Once API authentication has been implemented, you can call the following endpoint from your backend to generate the Sumsub access token.

The generated API signature must be included in the request headers when calling this API.

Endpoint

Method

POST

Endpoint

/partners/ssb/access-token

Authorization: Signature {GENERATED_SIGNATURE}

Payload 

{
  "externalUserId": "string",
  "customerType": "INDIVIDUAL | BUSINESS"
}

Field Description

  • externalUserId
    Unique identifier for the customer.

  • customerType
    Specifies the type of customer. Supported values are INDIVIDUAL or BUSINESS.
    This value is used to determine the appropriate verification level.

Response 

{
  "success": true,
  "data": {
    "token": "string",
    "userId": "string"
  }
}

Frontend Integration

Install the SDK

npm:

npm i @sumsub/websdk --save

yarn:

yarn add @sumsub/websdk

Import the SDK 

import snsWebSdk from "@sumsub/websdk";

Standalone:

<script src="https://static.sumsub.com/idensic/static/sns-websdk-builder.js"></script>

Create SDK Container 

<div id="sumsub-websdk-container"></div>

Initialize SDK 

function launchWebSdk(accessToken) {
  let snsWebSdkInstance = snsWebSdk
    .init(accessToken, () => this.getNewAccessToken())

    .withConf({
      lang: "en",
      theme: "dark",
    })

    .withOptions({
      addViewportTag: false,
      adaptIframeHeight: true,
    })

    .on("idCheck.onStepCompleted", (payload) => {
      console.log("onStepCompleted", payload);
    })

    .on("idCheck.onError", (error) => {
      console.log("onError", error);
    })

    .build();

  snsWebSdkInstance.launch("#sumsub-websdk-container");
}

function getNewAccessToken() {
  return Promise.resolve(newAccessToken);
}

React Integration 

import SumsubWebSdk from "@sumsub/websdk-react";

<SumsubWebSdk
  accessToken={accessToken}
  expirationHandler={accessTokenExpirationHandler}
  config={config}
  options={options}
  onMessage={messageHandler}
  onError={errorHandler}
/>;

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