Add a demo script to listen the events

Signed-off-by: Adi Bhagavath <[email protected]>

demo/src/listen-events.ts

@@ -0,0 +1,33 @@
+import { ApiPromise, WsProvider } from '@polkadot/api'
+
+async function main() {
+ const networkAddress = process.env.NETWORK_ADDRESS
+ ? process.env.NETWORK_ADDRESS
+ : 'ws://127.0.0.1:9944'
+ const provider = new WsProvider(networkAddress)
+ const api = await ApiPromise.create({ provider })
+
+ // Subscribe to system events
+ api.query.system.events((events) => {
+ // Loop through the array of events
+ events.forEach((record) => {
+ // Extract the phase, event type, and event data
+ const { event, phase } = record
+ const types = event.typeDef
+ const args = event.data.map((data) => data.toString())
+
+ // Print the event details
+ console.log(
+ `\nEvent: ${event.section}.${event.method} [${phase.toString()}]`
+ )
+ console.log(`\tParameters:`)
+ args.forEach((arg, index) => {
+ console.log(`\t\t${types[index].type}: ${arg}`)
+ })
+ })
+ })
+}
+
+main().catch((error) => {
+ console.error('Error:', error)
+})