Broadcast and Collect Within an Action

info

Only available on the test network

Overview

Broadcast and collect allows you to run an operation on each node in the Lit network, collect their responses, and aggregate those responses into a single data set shared across all of the nodes. This is useful if you'd like the ability to perform additional operations over their responses, such as calculating a median or average.

When you call this function, the responses from each node will be grouped and then returned back to each node for further processing.

Broadcasting and Collecting a fetch response

const code = `(async () => {
  const url = "https://api.weather.gov/gridpoints/TOP/31,80/forecast";
  const resp = await fetch(url).then((response) => response.json());
  const temp = resp.properties.periods[0].temperature;

  const temperatures = await Lit.Actions.broadcastAndCollect({
    name: "temperature",
    value: temp,
  });

  // at this point, temperatures is an array of all the values that all the nodes got
  const median = temperatures.sort()[Math.floor(temperatures.length / 2)];
  Lit.Actions.setResponse({response: median});
})();
`;

const client = new LitNodeClient({
    litNetwork: 'cayenne',
});
await client.connect();
const res = await client.executeJs({
    code,
    sessionSigs: {} // your session
    jsParams: {
      publicKey: "<your pkp public key>",
      sigName: 'fooSig',
    }
});

console.log("response from broadcast and collecting within a lit action: ", res);