Introduction

Welcome to this comprehensive guide on how to retrieve a list of ERC20 tokens that Overledger supports. In this guide, we will walk through what an ERC20 token is, what a Quant smart token is and how to call retrieve a list of ERC20 and QRC20 tokens endpoint.

What is an ERC20 token?

ERC20 is a standard for Fungible Tokens.

Fungibility refers to the fact that one token of the same type can be swapped for another token of the same type, without any change to the user holding the token. For example, swapping one pound coin with another pound coin has no affect to the user holding the initial or subsequent pound coin.

ERC20 on the other hand is an interface standard so that every token created using the ERC20 format has the same functionality.

What is a Quant smart token?

Quant smart tokens are ERC-20 or ERC-721 tokens expertly coded by a Ph.D. team and externally validated. They can be configured and deployed in less than three minutes without writing a single line of code in Quant Connect.
Also, they can be deployed across multiple chains.
Once deployed, you can control your token by using our function-rich smart contracts.

Prerequisites

• Create an account and generate your application's API keys
  Create an account on Quant Connect. Then, register your application to generate API keys to authorise your requests on Overledger APIs.

• Obtain an authorization token
  You must obtain an authorisation token to interact with Overledger's API and call any endpoint. This token will authenticate your requests and grant you access to the necessary endpoints. Please follow the authentication process provided by Overledger to get your authorisation token.

Retrieve a list of ERC20 and QRC20 tokens

To obtain a list of all supported fungible tokens, call the Supported Fungible Tokens endpoint.

This endpoint can be accessed with a simple GET request through Overledger, for example:

curl --request GET \
     --url 'https://api.sandbox.overledger.io/v2/tokens/fungible?location=' \
     --header 'accept: application/json'

We recommend submitting a filtered search to retrieve only tokens that meet your specified criteria.

These filters can be used for fungible tokens: location, contractType, unit.

Here is an example of querying if Overledger supports QNT on Ethereum Sepolia Testnet

curl --request GET \
     --url '<https://api.sandbox.overledger.io/v2/tokens/fungible?technology=ethereum&network=ethereum> sepolia testnet&contractType=ERC20&unit=QNT' \
     --header 'accept: application/json'

[
    {
        "unit": "QNT",
        "location": {
            "technology": "ethereum",
            "network": "ethereum sepolia testnet"
        },
        "smartContractId": "0xE617Ec4a06dEe539e83a0824b28c712Bf799b560",
        "decimalPlaces": 18,
        "contractType": "ERC20",
        "functions": [
            {
                "type": "Payment",
                "api": "/preparation/transaction"
            }
        ],
        "documentationUrl": "https://docs.overledger.io"
    }
]