refactor(sequencer-client): move FeeProviderImpl to separate file

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

Author: spalladino

yarn-project/sequencer-client/src/global_variable_builder/fee_provider.ts

@@ -0,0 +1,78 @@
+import { RollupContract } from '@aztec/ethereum/contracts';
+import type { ViemPublicClient } from '@aztec/ethereum/types';
+import { SlotNumber } from '@aztec/foundation/branded-types';
+import type { DateProvider } from '@aztec/foundation/timer';
+import { getNextL1SlotTimestamp } from '@aztec/stdlib/epoch-helpers';
+import { GasFees, ManaUsageEstimate } from '@aztec/stdlib/gas';
+import type { FeeProvider } from '@aztec/stdlib/tx';
+
+import { FeePredictor } from './fee_predictor.js';
+import type { GlobalVariableBuilderConfig } from './global_builder.js';
+
+/** Provides current and predicted fee information based on on-chain state. */
+export class FeeProviderImpl implements FeeProvider {
+  private currentMinFees: Promise<GasFees> = Promise.resolve(new GasFees(0, 0));
+  private currentL1BlockNumber: bigint | undefined = undefined;
+
+  private readonly rollupContract: RollupContract;
+  private readonly feePredictor: FeePredictor;
+  private readonly ethereumSlotDuration: number;
+  private readonly l1GenesisTime: bigint;
+
+  constructor(
+    private readonly dateProvider: DateProvider,
+    private readonly publicClient: ViemPublicClient,
+    config: GlobalVariableBuilderConfig,
+  ) {
+    this.ethereumSlotDuration = config.ethereumSlotDuration;
+    this.l1GenesisTime = config.l1GenesisTime;
+
+    this.rollupContract = new RollupContract(this.publicClient, config.l1Contracts.rollupAddress);
+    this.feePredictor = new FeePredictor(
+      this.rollupContract,
+      this.publicClient,
+      this.dateProvider,
+      config.slotDuration,
+      config.l1GenesisTime,
+      config.ethereumSlotDuration,
+    );
+  }
+
+  /**
+   * Computes the "current" min fees, e.g., the price that you currently should pay to get include in the next block
+   * @returns Min fees for the next block
+   */
+  private async computeCurrentMinFees(): Promise<GasFees> {
+    // Since this might be called in the middle of a slot where a block might have been published,
+    // we need to fetch the last block written, and estimate the earliest timestamp for the next block.
+    // The timestamp of that last block will act as a lower bound for the next block.
+
+    const lastCheckpoint = await this.rollupContract.getPendingCheckpoint();
+    const earliestTimestamp = await this.rollupContract.getTimestampForSlot(
+      SlotNumber.fromBigInt(BigInt(lastCheckpoint.slotNumber) + 1n),
+    );
+    const nextEthTimestamp = getNextL1SlotTimestamp(this.dateProvider.nowInSeconds(), {
+      l1GenesisTime: this.l1GenesisTime,
+      ethereumSlotDuration: this.ethereumSlotDuration,
+    });
+    const timestamp = earliestTimestamp > nextEthTimestamp ? earliestTimestamp : nextEthTimestamp;
+
+    return new GasFees(0, await this.rollupContract.getManaMinFeeAt(timestamp, true));
+  }
+
+  public async getCurrentMinFees(): Promise<GasFees> {
+    // Get the current block number
+    const blockNumber = await this.publicClient.getBlockNumber();
+
+    // If the L1 block number has changed then chain a new promise to get the current min fees
+    if (this.currentL1BlockNumber === undefined || blockNumber > this.currentL1BlockNumber) {
+      this.currentL1BlockNumber = blockNumber;
+      this.currentMinFees = this.currentMinFees.then(() => this.computeCurrentMinFees());
+    }
+    return this.currentMinFees;
+  }
+
+  public getPredictedMinFees(manaUsage?: ManaUsageEstimate): Promise<GasFees[]> {
+    return this.feePredictor.getPredictedMinFees(manaUsage ?? ManaUsageEstimate.Target);
+  }
+}

yarn-project/sequencer-client/src/global_variable_builder/global_builder.ts

@@ -4,102 +4,28 @@ import type { ViemPublicClient } from '@aztec/ethereum/types';
 import { BlockNumber, SlotNumber } from '@aztec/foundation/branded-types';
 import { Fr } from '@aztec/foundation/curves/bn254';
 import type { EthAddress } from '@aztec/foundation/eth-address';
-import { createLogger } from '@aztec/foundation/log';
 import type { DateProvider } from '@aztec/foundation/timer';
 import type { AztecAddress } from '@aztec/stdlib/aztec-address';
 import { type L1RollupConstants, getNextL1SlotTimestamp, getTimestampForSlot } from '@aztec/stdlib/epoch-helpers';
-import { GasFees, ManaUsageEstimate } from '@aztec/stdlib/gas';
+import { GasFees } from '@aztec/stdlib/gas';
 import type {
   BuildCheckpointGlobalVariablesOpts,
   CheckpointGlobalVariables,
-  FeeProvider,
   GlobalVariableBuilder as GlobalVariableBuilderInterface,
 } from '@aztec/stdlib/tx';
 import { GlobalVariables } from '@aztec/stdlib/tx';
 
-import { FeePredictor } from './fee_predictor.js';
-
 /** Configuration for the GlobalVariableBuilder (excludes L1 client config). */
 export type GlobalVariableBuilderConfig = {
   l1Contracts: Pick<L1ContractAddresses, 'rollupAddress'>;
   ethereumSlotDuration: number;
   rollupVersion: bigint;
 } & Pick<L1RollupConstants, 'slotDuration' | 'l1GenesisTime'>;
 
-/** Provides current and predicted fee information based on on-chain state. */
-export class FeeProviderImpl implements FeeProvider {
-  private currentMinFees: Promise<GasFees> = Promise.resolve(new GasFees(0, 0));
-  private currentL1BlockNumber: bigint | undefined = undefined;
-
-  private readonly rollupContract: RollupContract;
-  private readonly feePredictor: FeePredictor;
-  private readonly ethereumSlotDuration: number;
-  private readonly l1GenesisTime: bigint;
-
-  constructor(
-    private readonly dateProvider: DateProvider,
-    private readonly publicClient: ViemPublicClient,
-    config: GlobalVariableBuilderConfig,
-  ) {
-    this.ethereumSlotDuration = config.ethereumSlotDuration;
-    this.l1GenesisTime = config.l1GenesisTime;
-
-    this.rollupContract = new RollupContract(this.publicClient, config.l1Contracts.rollupAddress);
-    this.feePredictor = new FeePredictor(
-      this.rollupContract,
-      this.publicClient,
-      this.dateProvider,
-      config.slotDuration,
-      config.l1GenesisTime,
-      config.ethereumSlotDuration,
-    );
-  }
-
-  /**
-   * Computes the "current" min fees, e.g., the price that you currently should pay to get include in the next block
-   * @returns Min fees for the next block
-   */
-  private async computeCurrentMinFees(): Promise<GasFees> {
-    // Since this might be called in the middle of a slot where a block might have been published,
-    // we need to fetch the last block written, and estimate the earliest timestamp for the next block.
-    // The timestamp of that last block will act as a lower bound for the next block.
-
-    const lastCheckpoint = await this.rollupContract.getPendingCheckpoint();
-    const earliestTimestamp = await this.rollupContract.getTimestampForSlot(
-      SlotNumber.fromBigInt(BigInt(lastCheckpoint.slotNumber) + 1n),
-    );
-    const nextEthTimestamp = getNextL1SlotTimestamp(this.dateProvider.nowInSeconds(), {
-      l1GenesisTime: this.l1GenesisTime,
-      ethereumSlotDuration: this.ethereumSlotDuration,
-    });
-    const timestamp = earliestTimestamp > nextEthTimestamp ? earliestTimestamp : nextEthTimestamp;
-
-    return new GasFees(0, await this.rollupContract.getManaMinFeeAt(timestamp, true));
-  }
-
-  public async getCurrentMinFees(): Promise<GasFees> {
-    // Get the current block number
-    const blockNumber = await this.publicClient.getBlockNumber();
-
-    // If the L1 block number has changed then chain a new promise to get the current min fees
-    if (this.currentL1BlockNumber === undefined || blockNumber > this.currentL1BlockNumber) {
-      this.currentL1BlockNumber = blockNumber;
-      this.currentMinFees = this.currentMinFees.then(() => this.computeCurrentMinFees());
-    }
-    return this.currentMinFees;
-  }
-
-  public getPredictedMinFees(manaUsage?: ManaUsageEstimate): Promise<GasFees[]> {
-    return this.feePredictor.getPredictedMinFees(manaUsage ?? ManaUsageEstimate.Target);
-  }
-}
-
 /**
  * Simple global variables builder.
  */
 export class GlobalVariableBuilder implements GlobalVariableBuilderInterface {
-  private log = createLogger('sequencer:global_variable_builder');
-
   private readonly rollupContract: RollupContract;
   private readonly ethereumSlotDuration: number;
   private readonly aztecSlotDuration: number;

yarn-project/sequencer-client/src/global_variable_builder/index.ts

@@ -1,2 +1,3 @@
-export { FeeProviderImpl, GlobalVariableBuilder, type GlobalVariableBuilderConfig } from './global_builder.js';
+export { FeeProviderImpl } from './fee_provider.js';
+export { GlobalVariableBuilder, type GlobalVariableBuilderConfig } from './global_builder.js';
 export { FeePredictor } from './fee_predictor.js';