add payout script / example (#604)

Author: Leouarz

avail-js/examples/node-examples/package.json

@@ -11,6 +11,7 @@
     "data-submission": "npm run build && node build/node-examples/src/tx-data-availability-data-submission.js",
     "create-app-id": "npm run build && node build/node-examples/src/tx-data-availability-create-application-key.js",
     "staking-nominate": "npm run build && node build/node-examples/src/tx-staking-nominate-full-example.js",
+    "staking-payout": "npm run build && node build/node-examples/src/tx-staking-payout-stakers.js",
     "staking-validate": "npm run build && node build/node-examples/src/tx-staking-validate-full-example.js",
     "estimate-transaction-fees": "npm run build && node build/node-examples/src/estimate-transaction-fees.js",
     "subscribe-blocks": "npm run build && node build/node-examples/src/subscribe-blocks.js",

avail-js/examples/node-examples/src/tx-staking-payout-stakers.ts

@@ -0,0 +1,93 @@
+import { ISubmittableResult } from "@polkadot/types/types"
+import { H256 } from "@polkadot/types/interfaces/runtime"
+import { getKeyringFromSeed, initialize, disconnect } from "avail-js-sdk"
+import config from "../../config"
+
+/**
+ * Script to automate payouts.
+ */
+const main = async () => {
+  const api = await initialize(config.endpoint)
+
+  /* THINGS YOU CAN CHANGE */
+  // The account you'll do the payout with
+  const account = getKeyringFromSeed(config.seed)
+  const options = { app_id: 0, nonce: -1 }
+
+  // Put the list of validators you want to do the payout for, leave empty for all of them
+  const validatorStashes: string[] = []
+
+  // Number of days to check (how many era we'll check for pending rewards)
+  let nbEra = 1
+
+
+  /* THINGS YOU SHOULD NOT CHANGE */
+  // Get the active era
+  const activeEra = (await api.query.staking.currentEra()).toJSON() as number
+
+  // Set the starting era to scrap reward
+  if (nbEra > 84) nbEra = 84
+  const startEra = activeEra > nbEra ? activeEra - nbEra : 0
+
+  // We set a list of eras and validators to claim for
+  let toClaim: { era: number, validator: string }[] = []
+
+  for (let i = startEra; i < activeEra; i++) {
+    // We get the validators who earned reward during this era
+    const eraRewardPoints = (await api.query.staking.erasRewardPoints(i)).toJSON() as { total: number, individual: { [address: string]: number } }
+    const eraRewardPointsValidatorList = Object.keys(eraRewardPoints.individual)
+
+    // We get the validators where the payout has already been done for this era
+    const claimedRewards = (await api.query.staking.claimedRewards.entries(i)).map(x => (x[0].toHuman() as string[])[1])
+
+    // We get all validator WITH eraRewardPoints and WITHOUT already claimed reward
+    let validatorsWithPendingClaim = eraRewardPointsValidatorList.filter(x => !claimedRewards.includes(x))
+
+    // We filter by the specified stashes if there are any
+    if (validatorStashes.length > 0) {
+      validatorsWithPendingClaim = validatorsWithPendingClaim.filter(x => validatorStashes.includes(x))
+    }
+
+    // We update the global list
+    toClaim = [...toClaim, ...validatorsWithPendingClaim.map(x => { return { era: i, validator: x } })]
+    console.log(`Found ${validatorsWithPendingClaim.length} validators with pending claims for era ${i}`)
+  }
+
+  // We create all the transactions
+  const transactions = await Promise.all(toClaim.map(x => api.tx.staking.payoutStakers(x.validator, x.era)))
+  const chunks = []
+  const chunkSize = 5
+  for (let i = 0; i < transactions.length; i += chunkSize) {
+    const chunk = transactions.slice(i, i + chunkSize);
+    chunks.push(chunk);
+  }
+
+
+  // We batch them together
+  const batches = chunks.map(x => api.tx.utility.batchAll(x))
+  for (const [i, tx] of batches.entries()) {
+    console.log(`Sending batch transaction ${i + 1} of ${batches.length}`)
+
+    // Send the batch
+    const txResult = await new Promise<ISubmittableResult>((res) => {
+      tx.signAndSend(account, options, (result: ISubmittableResult) => {
+        if (result.isInBlock || result.isError) {
+          res(result)
+        }
+      })
+    })
+
+    // Error handling
+    if (!txResult.isError) {
+      console.log(`Payout done successfully for batch transaction ${i + 1} of ${batches.length} `)
+      console.log(`Tx Hash: ${txResult.txHash as H256}, Block Hash: ${txResult.status.asInBlock as H256}`)
+    } else {
+      console.log(`Transaction was not executed for batch transaction ${i + 1} of ${batches.length}`)
+    }
+  }
+
+  console.log("Everything was done, bye !")
+  await disconnect()
+  process.exit(0)
+}
+main()