Use provider-specified suggested priority fee when available, otherwi…

…se fallback onto existing logic of 1 gwei (ethers-io#4463).

src.ts/providers/abstract-provider.ts

@@ -383,6 +383,8 @@ export type PerformActionRequest = {
 } | {
     method: "getLogs",
     filter: PerformActionFilter
+} | {
+    method: "getPriorityFee"
 } | {
     method: "getStorage",
     address: string, position: bigint, blockTag: BlockTag
@@ -906,14 +908,21 @@ export class AbstractProvider implements Provider {
         const network = await this.getNetwork();
 
         const getFeeDataFunc = async () => {
-            const { _block, gasPrice } = await resolveProperties({
+            const { _block, gasPrice, priorityFee } = await resolveProperties({
                 _block: this.#getBlock("latest", false),
                 gasPrice: ((async () => {
                     try {
-                        const gasPrice = await this.#perform({ method: "getGasPrice" });
-                        return getBigInt(gasPrice, "%response");
+                        const value = await this.#perform({ method: "getGasPrice" });
+                        return getBigInt(value, "%response");
                     } catch (error) { }
                     return null
+                })()),
+                priorityFee: ((async () => {
+                    try {
+                        const value = await this.#perform({ method: "getPriorityFee" });
+                        return getBigInt(value, "%response");
+                    } catch (error) { }
+                    return null;
                 })())
             });
 
@@ -923,7 +932,7 @@ export class AbstractProvider implements Provider {
             // These are the recommended EIP-1559 heuristics for fee data
             const block = this._wrapBlock(_block, network);
             if (block && block.baseFeePerGas) {
-                maxPriorityFeePerGas = BigInt("1000000000");
+                maxPriorityFeePerGas = (priorityFee != null) ? priorityFee: BigInt("1000000000");
                 maxFeePerGas = (block.baseFeePerGas * BN_2) + maxPriorityFeePerGas;
             }
 

src.ts/providers/network.ts

@@ -346,26 +346,6 @@ function getGasStationPlugin(url: string) {
     });
 }
 
-// Used by Optimism for a custom priority fee
-function getPriorityFeePlugin(maxPriorityFeePerGas: bigint) {
-    return new FetchUrlFeeDataNetworkPlugin("data:", async (fetchFeeData, provider, request) => {
-        const feeData = await fetchFeeData();
-
-        // This should always fail
-        if (feeData.maxFeePerGas == null || feeData.maxPriorityFeePerGas == null) {
-            return feeData;
-        }
-
-        // Compute the corrected baseFee to recompute the updated values
-        const baseFee = feeData.maxFeePerGas - feeData.maxPriorityFeePerGas;
-        return {
-            gasPrice: feeData.gasPrice,
-            maxFeePerGas: (baseFee + maxPriorityFeePerGas),
-            maxPriorityFeePerGas
-        };
-    });
-}
-
 // See: https://chainlist.org
 let injected = false;
 function injectCommonNetworks(): void {
@@ -409,10 +389,10 @@ function injectCommonNetworks(): void {
     registerEth("kovan", 42, { ensNetwork: 42 });
     registerEth("sepolia", 11155111, { ensNetwork: 11155111 });
 
-    registerEth("classic", 61, { });
-    registerEth("classicKotti", 6, { });
 
 
+    registerEth("classic", 61, { });
+    registerEth("classicKotti", 6, { });
 
     registerEth("arbitrum", 42161, {
         ensNetwork: 1,
@@ -444,9 +424,7 @@ function injectCommonNetworks(): void {
 
     registerEth("optimism", 10, {
         ensNetwork: 1,
-        plugins: [
-            getPriorityFeePlugin(BigInt("1000000"))
-        ]
+        plugins: [ ]
     });
     registerEth("optimism-goerli", 420, { });
 

src.ts/providers/provider-etherscan.ts

@@ -26,6 +26,7 @@ import {
     hexlify, toQuantity,
     FetchRequest,
     assert, assertArgument, isError,
+//    parseUnits,
     toUtf8String
  } from "../utils/index.js";
 
@@ -421,6 +422,43 @@ export class EtherscanProvider extends AbstractProvider {
             case "getGasPrice":
                 return this.fetch("proxy", { action: "eth_gasPrice" });
 
+            case "getPriorityFee":
+                // This is temporary until Etherscan completes support
+                if (this.network.name === "mainnet") {
+                    return "1000000000";
+                } else if (this.network.name === "optimism") {
+                    return "1000000";
+                } else {
+                    throw new Error("fallback onto the AbstractProvider default");
+                }
+                /* Working with Etherscan to get this added:
+                try {
+                    const test = await this.fetch("proxy", {
+                        action: "eth_maxPriorityFeePerGas"
+                    });
+                    console.log(test);
+                    return test;
+                } catch (e) {
+                    console.log("DEBUG", e);
+                    throw e;
+                }
+                */
+                /* This might be safe; but due to rounding neither myself
+                   or Etherscan are necessarily comfortable with this. :)
+                try {
+                    const result = await this.fetch("gastracker", { action: "gasoracle" });
+                    console.log(result);
+                    const gasPrice = parseUnits(result.SafeGasPrice, "gwei");
+                    const baseFee = parseUnits(result.suggestBaseFee, "gwei");
+                    const priorityFee = gasPrice - baseFee;
+                    if (priorityFee < 0) { throw new Error("negative priority fee; defer to abstract provider default"); }
+                    return priorityFee;
+                } catch (error) {
+                    console.log("DEBUG", error);
+                    throw error;
+                }
+                */
+
             case "getBalance":
                 // Returns base-10 result
                 return this.fetch("account", {

src.ts/providers/provider-fallback.ts

@@ -458,6 +458,8 @@ export class FallbackProvider extends AbstractProvider {
                 return await provider.getCode(req.address, req.blockTag);
             case "getGasPrice":
                 return (await provider.getFeeData()).gasPrice;
+            case "getPriorityFee":
+                return (await provider.getFeeData()).maxPriorityFeePerGas;
             case "getLogs":
                 return await provider.getLogs(req.filter);
             case "getStorage":
@@ -614,6 +616,7 @@ export class FallbackProvider extends AbstractProvider {
             }
 
             case "getGasPrice":
+            case "getPriorityFee":
             case "estimateGas":
                 return getMedian(this.quorum, results);
 

src.ts/providers/provider-jsonrpc.ts

@@ -821,6 +821,9 @@ export abstract class JsonRpcApiProvider extends AbstractProvider {
             case "getGasPrice":
                 return { method: "eth_gasPrice", args: [] };
 
+            case "getPriorityFee":
+                return { method: "eth_maxPriorityFeePerGas", args: [ ] };
+
             case "getBalance":
                 return {
                     method: "eth_getBalance",