Koios TypeScript Client

Koios Typescript Client is a REST Client library which allows interacting with Koios Server Instances. Koios TypeScript Client Library is based on Koios Elastic Query Layer for Cardano Node by Cardano Community Guild Operators. Koios is best described as a Decentralized and Elastic RESTful query layer for exploring data on Cardano blockchain to consume within applications/wallets/explorers/etc. Resource and maintenance requirements for Cardano blockchain components (e.g. cardano-node, cardano-db-sync) are ever-growing. Along with that, every builder needs to identify how to query complex information from the chain.

Table of contents

• Prerequisites
• Features
• Getting Started
• Installation
• Usage
  • Get Koios Backend Service
  • Get Koios Backend Services
  • Advanced Query Example (Preview)
• Supported Environment Variables
• Contributing

Prerequisites

This project requires NodeJS (version 16 or later) and NPM. Node and NPM are really easy to install. To make sure you have them available on your machine, try running the following command.

$ npm -v ; node -v
9.6.3
v16.5.0

Features

• Synchronous REST messaging
• Pagination (Limit and Offset)
• Horizontal Filtering
• Vertical Filtering
• Sorting Supported
• Rate Control (soon)
• Inner Retry Mechanism upon Timeouts

Getting Started

These instructions will get you a copy of the project up and running on your local machine for development and testing purposes. See deployment for notes on how to deploy the project on a live system.

Installation

BEFORE YOU INSTALL: please read the prerequisites

Start with cloning this repo on your local machine:

$ git clone https://github.com/adabox-aio/koios-typescript-client.git
$ cd koios-typescript-client

To install and set up the library, run:

$ npm i @adabox/koios-ts-client

Usage

Import

import {BackendFactory} from "@adabox/koios-ts-client"

Get Koios Backend Service

• Mainnet

const koiosBackendService = BackendFactory.getKoiosMainnetService()

• Preview

const koiosBackendService = BackendFactory.getKoiosPreviewService()

• Preprod

const koiosBackendService = BackendFactory.getKoiosPreprodService()

Get Koios Backend Services

const koiosNetworkService = koiosBackendService.getNetworkService()
const koiosEpochService = koiosBackendService.getEpochService()
const koiosBlockService = koiosBackendService.getBlockService()
const koiosTransactionsService = koiosBackendService.getTransactionsService()
const koiosAddressService = koiosBackendService.getAddressService()
const koiosAssetService = koiosBackendService.getAssetService()
const koiosPoolService = koiosBackendService.getPoolService()
const koiosScriptService = koiosBackendService.getScriptService()
const koiosAccountService = koiosBackendService.getAccountService()

Advanced Query Example (Preview)

Querying a Descending Order of All Address Transactions since Block No. #42248 to Block No. #69447 (inclusive), Limited to Maximum of 10 Results.

const addresses = [
    'addr_test1qrvaadv0h7atv366u6966u4rft2svjlf5uajy8lkpsgdrc24rnskuetxz2u3m5ac22s3njvftxcl2fc8k8kjr088ge0qz98xmv',
]
const options = Options.builder()
    .option(Limit.of(10))
    .option(Offset.of(0))
    .option(Order.by("block_height", SortType.DESC))
    .option(Filter.of("block_height", FilterType.GTE, "42248"))
    .option(Filter.of("block_height", FilterType.LTE, "69447")).build();

const result = await koiosAddressService.getAddressTransactions(addresses, undefined, options)
console.log(result)

Error Handling

Koios TypeScript Client throws 2 types of errors,KoiosHttpError and KoiosTimeoutError. Each of these errors is extended from the built-in Error class, allowing you to properly catch it and handle it in your code.

import {KoiosHttpError, KoiosTimeoutError} from "@adabox/koios-ts-client";

try {
  const result = await koiosTransactionsService.getTransactionInformation(["abc"])
} catch (error) {
  if (error instanceof KoiosHttpError || error instanceof KoiosTimeoutError) {
    console.log(error) // Koios Error
  } else {
      throw error // rethrow other errors
  }
}

Supported Environment Variables

| Variable | Type | Description | Default | |------------------------|:-------:|-------------------------------------------------------------|:-------:| | KOIOS_MAX_RETRIES | integer | Sets the max retry count upon request timeout | 5 | | KOIOS_READ_TIMEOUT_SEC | integer | Sets the default read timeout for new connections (seconds) | 300 |

Contributing

Please read CONTRIBUTING.md for details on our code of conduct, and the process for submitting pull requests to us.

1. Fork it!
2. Create your feature branch: git checkout -b my-new-feature
3. Add your changes: git add .
4. Commit your changes: git commit -am 'Add some feature'
5. Push to the branch: git push origin my-new-feature
6. Submit a pull request :sunglasses: