[auto-self-nominate] Implement repeating self nomination

auto-self-nominate/index.ts

@@ -0,0 +1,166 @@
+import { U64 } from "codechain-primitives/lib";
+import { SDK } from "codechain-sdk";
+import { PlatformAddress } from "codechain-sdk/lib/core/classes";
+import { Custom } from "codechain-sdk/lib/core/transaction/Custom";
+
+const RLP = require("rlp");
+
+const ACTION_TAG_SELF_NOMINATE = 4;
+const STAKE_ACTION_HANDLER_ID = 2;
+const NEED_NOMINATION_UNDER_TERM_LEFT = 5;
+
+interface CandidatesInfo {
+    [key: string]: [number, number];
+}
+
+function getConfig(field: string): string {
+    const c = process.env[field];
+    if (c == null) {
+        throw new Error(`${field} is not specified`);
+    }
+    return c;
+}
+
+const networkId = getConfig("NETWORK_ID");
+const rpcUrl = getConfig("RPC_URL");
+
+const sdk = (() => {
+    console.log(`sdk ${networkId} ${rpcUrl}`);
+    return new SDK({
+        server: networkId,
+        networkId: rpcUrl,
+    });
+})();
+
+function decodePlatformAddressFromPubkey(buffer: Buffer): PlatformAddress {
+    const pubkey = buffer.toString("hex");
+    return PlatformAddress.fromPublic(pubkey, {
+        networkId: sdk.networkId,
+    });
+}
+
+function decodeNumber(buffer: Buffer): number {
+    return parseInt(buffer.toString("hex"), 16);
+}
+
+async function getCurrentTermId(bestBlockNumber: number): Promise<number | null> {
+    return new Promise((resolve, reject) => {
+        sdk.rpc
+            .sendRpcRequest("chain_getTermMetadata", [bestBlockNumber])
+            .then(result => {
+                if (result === null) {
+                    resolve(null);
+                }
+                const [prevTermLastBlockNumber, currentTermId] = result;
+                if (
+                    typeof prevTermLastBlockNumber === "number" &&
+                    typeof currentTermId === "number"
+                ) {
+                    resolve(currentTermId);
+                }
+                reject(
+                    Error(
+                        `Expected getTermMetadata to return [number, number] | null but it returned ${result}`,
+                    ),
+                );
+            })
+            .catch(reject);
+    });
+}
+
+async function sendSelfNominateTransaction(
+    accountInfo: { account: string; passphrase: string },
+    params: { deposit: U64; metadata: string },
+) {
+    const tx = createSelfNomination(params);
+    const { account, passphrase } = accountInfo;
+    await sdk.rpc.account.sendTransaction({
+        tx,
+        account,
+        passphrase,
+    });
+}
+
+function createSelfNomination(params: { deposit: U64; metadata: string }): Custom {
+    const { deposit, metadata } = params;
+    const handlerId = new U64(STAKE_ACTION_HANDLER_ID);
+    const actionTag = ACTION_TAG_SELF_NOMINATE;
+    const bytes = RLP.encode([actionTag, deposit, metadata]);
+    return new Custom(
+        {
+            handlerId,
+            bytes,
+        },
+        networkId,
+    );
+}
+
+async function getCandidatesInfo(bestBlockNumber: number): Promise<CandidatesInfo> {
+    const retval: CandidatesInfo = {};
+    const data = (await sdk.rpc.engine.getCustomActionData(2, ["Candidates"], bestBlockNumber))!;
+    const list: Buffer[][] = RLP.decode(Buffer.from(data, "hex"));
+    list.forEach(
+        ([encodedPubkey, encodedDeposit, encodedNominationEnd]) =>
+            (retval[decodePlatformAddressFromPubkey(encodedPubkey).value] = [
+                decodeNumber(encodedNominationEnd),
+                decodeNumber(encodedDeposit),
+            ]),
+    );
+    return retval;
+}
+
+async function supplementaryNoimationDeposit(
+    info: CandidatesInfo,
+    bestBlockNumber: number,
+    address: string,
+    targetDeposit: number,
+): Promise<number | null> {
+    if (!info.hasOwnProperty(address)) {
+        throw new Error(`SelfNominate first with specific deposit vakue before repeating`);
+    }
+    const [deposit, nominationEndAt] = info[address];
+    const currentTermId = (await getCurrentTermId(bestBlockNumber))!;
+    if (nominationEndAt - currentTermId >= NEED_NOMINATION_UNDER_TERM_LEFT) {
+        return null;
+    }
+    if (deposit < targetDeposit) {
+        return targetDeposit - deposit;
+    } else {
+        return 0;
+    }
+}
+
+async function main() {
+    const accountAddress = getConfig("ACCOUNT_ADDRESS");
+    const passphrase = getConfig("PASSPHRASE");
+    const metadata = getConfig("METADATA");
+    const targetDeposit = parseInt(getConfig("TARGET_DEPOSIT"), 10);
+
+    setInterval(async () => {
+        const bestBlockNumber = await sdk.rpc.chain.getBestBlockNumber()!;
+        const info = await getCandidatesInfo(bestBlockNumber);
+        const supplement = await supplementaryNoimationDeposit(
+            info,
+            bestBlockNumber,
+            accountAddress,
+            targetDeposit,
+        );
+        if (supplement != null) {
+            await sendSelfNominateTransaction(
+                {
+                    account: accountAddress,
+                    passphrase,
+                },
+                {
+                    deposit: new U64(supplement),
+                    metadata,
+                },
+            );
+        }
+    }, 600_000); // 10 minutes interval
+}
+
+main().catch(error => {
+    console.log({ error });
+    throw error;
+});