Fetching Markets

Quickstart

Here we are fetching 10 active markets with the Sports tag.

import { MarketStatus } from "@zeitgeistpm/indexer";
import {
  create,
  FullContext,
  mainnet,
  MarketList,
  Sdk,
} from "@zeitgeistpm/sdk";

const sdk: Sdk<FullContext> = await create(mainnet());

const activeSportsMarkets: MarketList<FullContext> =
  await sdk.model.markets.list({
    limit: 10,
    where: {
      tags_containsAll: ["Sports"],
      status_eq: MarketStatus.Active,
    },
  });

activeSportsMarkets.forEach((market) => {
  console.log(`${market.marketId}: ${market.question}`);
});

Returns

Market type ref

к сведению

Note that since we are creating a FullContext sdk the indexer will be the preferred method of fetching markets and will give access to more fine grained filtering like by status, tags, creator etc.

Fetching With Rpc

If you have a requirement to fetch directly from the chain and decentralized storage(IPFS) you can start the sdk in RpcContext mode. The following example will give the same result as the indexed one above with the exception of limiting results.

осторожно

Currently this fetches all markets on chain and wont be a viable long term. But features to paginate and stream the list of markets is coming shortly.

import {
  create,
  mainnetRpc,
  MarketList,
  RpcContext,
  Sdk,
} from "@zeitgeistpm/sdk";
import { isNotNull } from "@zeitgeistpm/utility/dist/null";

const sdk: Sdk<RpcContext> = await create(mainnetRpc());

const all: MarketList<RpcContext> = await sdk.model.markets.list();

const activeSportsMarkets = (
  await Promise.all(
    all.map(async (market) => {
      if (!market.status.isActive) {
        return null;
      }

      /**
       * Saturation is a process that fetches metadata for a market from external storage(IPFS)
       */
      const marketWithMetadata = await market.saturate();

      /**
       * Saturated markets have access to the metadata like tags, categories, question, etc.
       */
      if (marketWithMetadata.tags?.includes("Sports")) {
        return marketWithMetadata;
      }

      return null;
    })
  )
).filter(isNotNull);

activeSportsMarkets.forEach((market) => {
  console.log(`${market.marketId}: ${market.question}`);
});

Forcing Rpc

If you are working with a FullContext sdk it will favour the indexer when querying markets. But if you want to force querying on chain data you can use it asRpc which will in effect make it a RpcContext sdk.

к сведению

Note that asRpc() clones the sdk and will reuse the underlying websocket connection, but will not affect the behavior of the sdk it was cloned from.

import {
  create,
  FullContext,
  mainnet,
  MarketList,
  RpcContext,
  Sdk,
} from "@zeitgeistpm/sdk";

const sdk: Sdk<FullContext> = await create(mainnet());

/**
 * Clone the sdk and force it to use the rpc api.
 */
const rpcSdk: Sdk<RpcContext> = sdk.asRpc();

const markets: MarketList<RpcContext> = await rpcSdk.model.markets.list();

/**
 * Saturate the markets with data from IPFS so we can peek its question
 */
const saturatedMarkets = await Promise.all(
  markets.slice(0, 10).map(async (market) => market.saturate())
);

saturatedMarkets.forEach((market) => {
  console.log(`${market.marketId}: ${market.question}`);
});