feat: Remote quote provider (#8946)

Adds an http quote provider that sends a fetch request to the target URL
to get a quote, instead of using a hardcoded value from env vars.

Builds on #8864

Author: spalladino

yarn-project/foundation/src/config/env_var.ts

@@ -104,6 +104,7 @@ export type EnvVar =
   | 'PXE_PROVER_ENABLED'
   | 'QUOTE_PROVIDER_BASIS_POINT_FEE'
   | 'QUOTE_PROVIDER_BOND_AMOUNT'
+  | 'QUOTE_PROVIDER_URL'
   | 'REGISTRY_CONTRACT_ADDRESS'
   | 'ROLLUP_CONTRACT_ADDRESS'
   | 'SEQ_ALLOWED_SETUP_FN'

yarn-project/prover-node/package.json

@@ -86,4 +86,4 @@
   "engines": {
     "node": ">=18"
   }
-}
+}

yarn-project/prover-node/src/config.ts

@@ -36,6 +36,7 @@ export type ProverNodeConfig = ArchiverConfig &
 export type QuoteProviderConfig = {
   quoteProviderBasisPointFee: number;
   quoteProviderBondAmount: bigint;
+  quoteProviderUrl?: string;
 };
 
 const specificProverNodeConfigMappings: ConfigMappingsType<
@@ -64,6 +65,11 @@ const quoteProviderConfigMappings: ConfigMappingsType<QuoteProviderConfig> = {
     description: 'The bond amount to charge for providing quotes',
     ...bigintConfigHelper(1000n),
   },
+  quoteProviderUrl: {
+    env: 'QUOTE_PROVIDER_URL',
+    description:
+      'The URL of the remote quote provider. Overrides QUOTE_PROVIDER_BASIS_POINT_FEE and QUOTE_PROVIDER_BOND_AMOUNT.',
+  },
 };
 
 export const proverNodeConfigMappings: ConfigMappingsType<ProverNodeConfig> = {

yarn-project/prover-node/src/factory.ts

@@ -18,6 +18,7 @@ import { ClaimsMonitor } from './monitors/claims-monitor.js';
 import { EpochMonitor } from './monitors/epoch-monitor.js';
 import { createProverCoordination } from './prover-coordination/factory.js';
 import { ProverNode } from './prover-node.js';
+import { HttpQuoteProvider } from './quote-provider/http.js';
 import { SimpleQuoteProvider } from './quote-provider/simple.js';
 import { QuoteSigner } from './quote-signer.js';
 
@@ -78,7 +79,9 @@ export async function createProverNode(
 }
 
 function createQuoteProvider(config: QuoteProviderConfig) {
-  return new SimpleQuoteProvider(config.quoteProviderBasisPointFee, config.quoteProviderBondAmount);
+  return config.quoteProviderUrl
+    ? new HttpQuoteProvider(config.quoteProviderUrl)
+    : new SimpleQuoteProvider(config.quoteProviderBasisPointFee, config.quoteProviderBondAmount);
 }
 
 function createQuoteSigner(config: ProverNodeConfig) {

yarn-project/prover-node/src/prover-node.test.ts

@@ -150,7 +150,7 @@ describe('prover-node', () => {
     it('sends a quote on a finished epoch', async () => {
       await proverNode.handleEpochCompleted(10n);
 
-      expect(quoteProvider.getQuote).toHaveBeenCalledWith(blocks);
+      expect(quoteProvider.getQuote).toHaveBeenCalledWith(10, blocks);
       expect(quoteSigner.sign).toHaveBeenCalledWith(expect.objectContaining(partialQuote));
       expect(coordination.addEpochProofQuote).toHaveBeenCalledTimes(1);
 

yarn-project/prover-node/src/prover-node.ts

@@ -116,7 +116,7 @@ export class ProverNode implements ClaimsMonitorHandler, EpochMonitorHandler {
   async handleEpochCompleted(epochNumber: bigint): Promise<void> {
     try {
       const blocks = await this.l2BlockSource.getBlocksForEpoch(epochNumber);
-      const partialQuote = await this.quoteProvider.getQuote(blocks);
+      const partialQuote = await this.quoteProvider.getQuote(Number(epochNumber), blocks);
       if (!partialQuote) {
         this.log.verbose(`No quote produced for epoch ${epochNumber}`);
         return;

yarn-project/prover-node/src/quote-provider/http.test.ts

@@ -0,0 +1,75 @@
+import { L2Block } from '@aztec/circuit-types';
+import { times } from '@aztec/foundation/collection';
+import { promiseWithResolvers } from '@aztec/foundation/promise';
+
+import { type Server, createServer } from 'http';
+import { type AddressInfo } from 'net';
+
+import { HttpQuoteProvider } from './http.js';
+
+describe('HttpQuoteProvider', () => {
+  let server: Server;
+  let port: number;
+
+  let status: number = 200;
+  let response: any = {};
+  let request: any = {};
+
+  let provider: HttpQuoteProvider;
+  let blocks: L2Block[];
+
+  beforeAll(async () => {
+    server = createServer({ keepAliveTimeout: 60000 }, (req, res) => {
+      const chunks: Buffer[] = [];
+      req
+        .on('data', (chunk: Buffer) => {
+          chunks.push(chunk);
+        })
+        .on('end', () => {
+          request = JSON.parse(Buffer.concat(chunks).toString());
+        });
+
+      res.writeHead(status, { 'Content-Type': 'application/json' });
+      res.end(JSON.stringify(response));
+    });
+
+    const { promise, resolve } = promiseWithResolvers();
+    server.listen(0, '127.0.0.1', () => resolve(null));
+    await promise;
+    port = (server.address() as AddressInfo).port;
+  });
+
+  beforeEach(() => {
+    provider = new HttpQuoteProvider(`http://127.0.0.1:${port}`);
+    blocks = times(3, i => L2Block.random(i + 1, 4));
+    response = { basisPointFee: 100, bondAmount: '100000000000000000000', validUntilSlot: '100' };
+  });
+
+  afterAll(() => {
+    server?.close();
+  });
+
+  it('requests a quote sending epoch data', async () => {
+    const quote = await provider.getQuote(1, blocks);
+
+    expect(request).toEqual(
+      expect.objectContaining({ epochNumber: 1, fromBlock: 1, toBlock: 3, txCount: 12, totalFees: expect.any(String) }),
+    );
+
+    expect(quote).toEqual({
+      basisPointFee: response.basisPointFee,
+      bondAmount: BigInt(response.bondAmount),
+      validUntilSlot: BigInt(response.validUntilSlot),
+    });
+  });
+
+  it('throws an error if the response is missing required fields', async () => {
+    response = { basisPointFee: 100 };
+    await expect(provider.getQuote(1, blocks)).rejects.toThrow(/Missing required fields/i);
+  });
+
+  it('throws an error if the response is not ok', async () => {
+    status = 400;
+    await expect(provider.getQuote(1, blocks)).rejects.toThrow(/Failed to fetch quote/i);
+  });
+});

yarn-project/prover-node/src/quote-provider/http.ts

@@ -1,2 +1,47 @@
-// TODO: Implement me! This should send a request to a configurable URL to get the quote.
-export class HttpQuoteProvider {}
+import { type L2Block } from '@aztec/circuit-types';
+
+import { type QuoteProvider, type QuoteProviderResult } from './index.js';
+import { getTotalFees, getTxCount } from './utils.js';
+
+export class HttpQuoteProvider implements QuoteProvider {
+  constructor(private readonly url: string) {}
+
+  public async getQuote(epochNumber: number, epoch: L2Block[]): Promise<QuoteProviderResult | undefined> {
+    const payload: HttpQuoteRequestPayload = {
+      epochNumber,
+      fromBlock: epoch[0].number,
+      toBlock: epoch.at(-1)!.number,
+      totalFees: getTotalFees(epoch).toString(),
+      txCount: getTxCount(epoch),
+    };
+
+    const response = await fetch(this.url, {
+      method: 'POST',
+      body: JSON.stringify(payload),
+      headers: { 'content-type': 'application/json' },
+    });
+
+    if (!response.ok) {
+      throw new Error(`Failed to fetch quote: ${response.statusText}`);
+    }
+
+    const data = await response.json();
+    if (!data.basisPointFee || !data.bondAmount) {
+      throw new Error(`Missing required fields in response: ${JSON.stringify(data)}`);
+    }
+
+    const basisPointFee = Number(data.basisPointFee);
+    const bondAmount = BigInt(data.bondAmount);
+    const validUntilSlot = data.validUntilSlot ? BigInt(data.validUntilSlot) : undefined;
+
+    return { basisPointFee, bondAmount, validUntilSlot };
+  }
+}
+
+export type HttpQuoteRequestPayload = {
+  epochNumber: number;
+  fromBlock: number;
+  toBlock: number;
+  totalFees: string;
+  txCount: number;
+};

yarn-project/prover-node/src/quote-provider/index.ts

@@ -1,8 +1,8 @@
 import { type EpochProofQuotePayload, type L2Block } from '@aztec/circuit-types';
 
-type QuoteProviderResult = Pick<EpochProofQuotePayload, 'basisPointFee' | 'bondAmount'> &
+export type QuoteProviderResult = Pick<EpochProofQuotePayload, 'basisPointFee' | 'bondAmount'> &
   Partial<Pick<EpochProofQuotePayload, 'validUntilSlot'>>;
 
 export interface QuoteProvider {
-  getQuote(epoch: L2Block[]): Promise<QuoteProviderResult | undefined>;
+  getQuote(epochNumber: number, epoch: L2Block[]): Promise<QuoteProviderResult | undefined>;
 }

yarn-project/prover-node/src/quote-provider/simple.ts

@@ -5,7 +5,10 @@ import { type QuoteProvider } from './index.js';
 export class SimpleQuoteProvider implements QuoteProvider {
   constructor(public readonly basisPointFee: number, public readonly bondAmount: bigint) {}
 
-  getQuote(_epoch: L2Block[]): Promise<Pick<EpochProofQuotePayload, 'basisPointFee' | 'bondAmount'>> {
+  getQuote(
+    _epochNumber: number,
+    _epoch: L2Block[],
+  ): Promise<Pick<EpochProofQuotePayload, 'basisPointFee' | 'bondAmount'>> {
     const { basisPointFee, bondAmount } = this;
     return Promise.resolve({ basisPointFee, bondAmount });
   }