refactor(experimental): Use the native fetch built into Node 18+ (#…

…1802)

# Summary

OK, so here's what I'm thinking.

`node-fetch` is in this weird state where:

- they refuse to build CommonJS bundles for the 3.x line
- the 2.x line supports `HttpAgent`
  - note that browsers will never support `HttpAgent`
- the 2.x line does not support HTTP/2

This means that we're taking on a huge dependency and exposing its config through web3.js, but will never end up in the ideal state (HTTP/2 support everywhere).

In this PR, we throw in the towel and make the _default_ transport that ships with web3.js API compatible with the `fetch` in both Node and browsers.

From that point:

- We could write our own HTTP/2 transport that's API compatible with `fetch()` and ship that
- Someone _else_ could write an all-singing, all-dancing transport _specifically_ for Node and open source it

Addresses #1680.

packages/fetch-impl/package.json

@@ -45,7 +45,6 @@
         "@solana/eslint-config-solana": "^1.0.2",
         "@swc/jest": "^0.2.29",
         "@types/jest": "^29.5.6",
-        "@types/node-fetch": "^2.6.4",
         "@typescript-eslint/eslint-plugin": "^6.7.0",
         "@typescript-eslint/parser": "^6.3.0",
         "agadoo": "^3.0.0",
@@ -61,8 +60,5 @@
         "tsconfig": "workspace:*",
         "tsup": "7.2.0",
         "typescript": "^5.1.6"
-    },
-    "peerDependencies": {
-        "node-fetch": "^2.6.7"
     }
 }

packages/fetch-impl/src/index.node.ts

@@ -1,8 +1,2 @@
-// When building the browser bundle, this import gets replaced by `globalThis.fetch`.
-import fetchImpl from 'node-fetch';
-
-export default typeof globalThis.fetch === 'function'
-    ? // The Fetch API is supported experimentally in Node 17.5+ and natively in Node 18+.
-      globalThis.fetch
-    : // Otherwise use the polyfill.
-      fetchImpl;
+// TODO(https://github.com/solana-labs/solana-web3.js/issues/1787) Write HTTP/2 implementation.
+export default globalThis.fetch; // The Fetch API is supported natively in Node 18+.

packages/rpc-transport/package.json

@@ -90,7 +90,6 @@
         "ws-impl": "workspace:*"
     },
     "peerDependencies": {
-        "node-fetch": "^2.6.7",
         "ws": "^8.14.0"
     },
     "bundlewatch": {

packages/rpc-transport/src/transports/http/http-transport.ts

@@ -1,6 +1,3 @@
-import type { Agent as NodeHttpAgent } from 'node:http';
-import type { Agent as NodeHttpsAgent } from 'node:https';
-
 import fetchImpl from 'fetch-impl';
 
 import { IRpcTransport } from '../transport-types';
@@ -13,29 +10,20 @@ import {
 
 type Config = Readonly<{
     headers?: AllowedHttpRequestHeaders;
-    httpAgentNodeOnly?: NodeHttpAgent | NodeHttpsAgent | ((parsedUrl: URL) => NodeHttpAgent | NodeHttpsAgent);
     url: string;
 }>;
 
-export function createHttpTransport({ httpAgentNodeOnly, headers, url }: Config): IRpcTransport {
+export function createHttpTransport({ headers, url }: Config): IRpcTransport {
     if (__DEV__ && headers) {
         assertIsAllowedHttpRequestHeaders(headers);
     }
-    const agent = __NODEJS__ ? httpAgentNodeOnly : undefined;
-    if (__DEV__ && httpAgentNodeOnly != null) {
-        console.warn(
-            'createHttpTransport(): The `httpAgentNodeOnly` config you supplied has been ' +
-                'ignored; HTTP agents are only usable in Node environments.'
-        );
-    }
     const customHeaders = headers && normalizeHeaders(headers);
     return async function makeHttpRequest<TResponse>({
         payload,
         signal,
     }: Parameters<IRpcTransport>[0]): Promise<TResponse> {
         const body = JSON.stringify(payload);
         const requestInfo = {
-            agent,
             body,
             headers: {
                 ...customHeaders,