Subscribe to wire

Error handling is omitted from example code for brevity.

api

The WireAPI.SubscribeWire API enables clients to subscribe to a wire.

cli

Use the wire command.

./volt wire --help

Subscribe to a wire using the cli wire command along with the -s or --subscribe switch:

./volt wire <wire id> -s

All wire data will be written to STDOUT. This enables flows such as:

./volt wire @demo-wire -s | wire-data.log

fusebox

Navigate to the wire in the resource explorer and use the ‘subscribe’ button on the bottom panel, which contains a ‘headphones’ icon.

javascript

Use the SubscribeWire API, the callback will be called every time new data arrives.

grpc

import grpc from "@grpc/grpc-js";
import { VoltClient } from "@tdxvolt/volt-client-grpc";

const client = new VoltClient(grpc);

const configPath = "./volt.config.json";

client
  .initialise(configPath)
  .then(() => {
    return new Promise((resolve, reject) => {
      const sub = client.SubscribeWire({ wire_id: "@wire-demo" });

      sub.on("error", (err) => {
      reject(err);
      });

      sub.on("data", (response) => {
      console.log(Buffer.from(response.chunk, "base64").toString());
      });

      sub.on("end", () => {
      resolve();
      });
    });
  })
  .catch((err) => {
    console.error("failure in subscribe-wire [%s]", err.message);
  });

web

  const sub = client.SubscribeWire({ wireId });
  sub.on("error", (err) => {
    console.error(err);
  });

  sub.on("data", (response) => {
    console.log(atob(response.chunk));
  });

  sub.on("end", () => {
    console.log("subscription ended");
  });

C++

examples coming soon...