Data Service API#

For historical or aggregated queries — asset search, DEX exchange history, paginated transaction lists — a data service is faster than replaying a node’s transaction history yourself. @decentralchain/data-service-client-js is the official TypeScript client for it.

Note

Verified against the published package on npm, @decentralchain/data-service-client-js v4.2.0 (2026-09-28) — its README’s API matches the monorepo’s in-progress data-service-client (renamed, unpublished) source exactly, so both are covered by the examples below. Install the current, published name.

Important

The package does not hardcode a production data-service URL — rootUrl is a required constructor option, and the matcher address is likewise supplied by the caller for DEX queries. This page does not state a specific production rootUrl or matcher address, since neither is published in the SDK or node-scala source; confirm the current values with whoever operates your target network’s data service and matcher before using the examples below.

Installing#

npm install @decentralchain/data-service-client-js

Requires Node.js >= 24 and an ESM environment ("type": "module"). Note the default export — this package doesn’t use a named { DataServiceClient } import.

Connecting#

import DataServiceClient from '@decentralchain/data-service-client-js';

const client = new DataServiceClient({
  rootUrl: 'https://<your-data-service-host>/v0',
});

Option	Required	Purpose
`rootUrl`	Yes	Base URL of the data service API
`fetch`	No	Custom `fetch` implementation
`parse`	No	Custom JSON parser
`transform`	No	Custom response transformer

Methods#

Method	Purpose
`getAssets(...ids)`	Fetch one or more assets by ID
`getAssetsByTicker(ticker)`	Fetch assets by ticker symbol (`'*'` for all)
`getCandles(amountAsset, priceAsset, opts)`	OHLCV candles for a trading pair
`getPairs(matcherAddress)`	Returns a function to fetch pair data for a given matcher
`getExchangeTxs(opts?)`	Exchange (DEX trade) transactions, by ID or filtered/paginated
`getTransferTxs(opts?)`	Transfer transactions
`getMassTransferTxs(opts?)`	Mass transfer transactions
`aliases.getById(id)` / `getByIdList(ids)` / `getByAddress(address, opts?)`	Alias lookups

All methods return Promise<{ data: T; fetchMore?: (count: number) => Promise }> — call fetchMore to page through a result set without re-specifying filters.

Example: exchange history for a pair#

const { data: candles } = await client.getCandles(amountAssetId, priceAssetId, {
  timeStart: '2026-01-01',
  timeEnd: '2026-12-31',
  interval: '1d',
  matcher: matcherAddress,
});

const result = await client.getExchangeTxs({ limit: 10, sort: 'desc' });
console.log(result.data);
if (result.fetchMore) {
  const next = await result.fetchMore(10);
}

Matcher address#

Several methods (getPairs, getCandles) take a matcher address as a parameter rather than assuming a single network-wide matcher — DecentralChain’s DEX matcher is operated as its own service, and its base URL and address are not published in node-scala or the SDK source. Obtain the current matcher address and API base URL from its operator before building against it.