2025-11-13 22:33:26 -07:00

123 lines
4.7 KiB
JavaScript

/**
* Initialization for the workerd runtime.
*
* The file must be imported at the top level the worker.
*/
import { AsyncLocalStorage } from "node:async_hooks";
import process from "node:process";
import stream from "node:stream";
// @ts-expect-error: resolved by wrangler build
import * as nextEnvVars from "./next-env.mjs";
const cloudflareContextALS = new AsyncLocalStorage();
// Note: this symbol needs to be kept in sync with `src/api/get-cloudflare-context.ts`
Object.defineProperty(globalThis, Symbol.for("__cloudflare-context__"), {
get() {
return cloudflareContextALS.getStore();
},
});
/**
* Executes the handler with the Cloudflare context.
*/
export async function runWithCloudflareRequestContext(request, env, ctx, handler) {
init(request, env);
return cloudflareContextALS.run({ env, ctx, cf: request.cf }, handler);
}
let initialized = false;
/**
* Initializes the runtime on the first call,
* no-op on subsequent invocations.
*/
function init(request, env) {
if (initialized) {
return;
}
initialized = true;
const url = new URL(request.url);
initRuntime();
populateProcessEnv(url, env);
}
function initRuntime() {
// Some packages rely on `process.version` and `process.versions.node` (i.e. Jose@4)
// TODO: Remove when https://github.com/unjs/unenv/pull/493 is merged
Object.assign(process, { version: process.version || "v22.14.0" });
// @ts-expect-error Node type does not match workerd
Object.assign(process.versions, { node: "22.14.0", ...process.versions });
globalThis.__dirname ??= "";
globalThis.__filename ??= "";
// Some packages rely on `import.meta.url` but it is undefined in workerd
// For example it causes a bunch of issues, and will make even import crash with payload
import.meta.url ??= "file:///worker.js";
// Do not crash on cache not supported
// https://github.com/cloudflare/workerd/pull/2434
// compatibility flag "cache_option_enabled" -> does not support "force-cache"
const __original_fetch = globalThis.fetch;
globalThis.fetch = (input, init) => {
if (init) {
delete init.cache;
}
return __original_fetch(input, init);
};
const CustomRequest = class extends globalThis.Request {
constructor(input, init) {
if (init) {
delete init.cache;
// https://github.com/cloudflare/workerd/issues/2746
// https://github.com/cloudflare/workerd/issues/3245
Object.defineProperty(init, "body", {
// @ts-ignore
value: init.body instanceof stream.Readable ? ReadableStream.from(init.body) : init.body,
});
}
super(input, init);
}
};
Object.assign(globalThis, {
Request: CustomRequest,
__BUILD_TIMESTAMP_MS__,
__NEXT_BASE_PATH__,
__ASSETS_RUN_WORKER_FIRST__,
__TRAILING_SLASH__,
// The external middleware will use the convertTo function of the `edge` converter
// by default it will try to fetch the request, but since we are running everything in the same worker
// we need to use the request as is.
__dangerous_ON_edge_converter_returns_request: true,
});
}
/**
* Populate process.env with:
* - the environment variables and secrets from the cloudflare platform
* - the variables from Next .env* files
* - the origin resolver information
*/
function populateProcessEnv(url, env) {
for (const [key, value] of Object.entries(env)) {
if (typeof value === "string") {
process.env[key] = value;
}
}
const mode = env.NEXTJS_ENV ?? "production";
if (nextEnvVars[mode]) {
for (const key in nextEnvVars[mode]) {
process.env[key] ??= nextEnvVars[mode][key];
}
}
// Set the default Origin for the origin resolver.
// This is only needed for an external middleware bundle
process.env.OPEN_NEXT_ORIGIN = JSON.stringify({
default: {
host: url.hostname,
protocol: url.protocol.slice(0, -1),
port: url.port,
},
});
/* We need to set this environment variable to make redirects work properly in preview mode.
* Next sets this in standalone mode during `startServer`. Without this the protocol would always be `https` here:
* https://github.com/vercel/next.js/blob/6b1e48080e896e0d44a05fe009cb79d2d3f91774/packages/next/src/server/app-render/action-handler.ts#L307-L316
*/
process.env.__NEXT_PRIVATE_ORIGIN = url.origin;
// `__DEPLOYMENT_ID__` is a string (passed via ESBuild).
if (__DEPLOYMENT_ID__) {
process.env.DEPLOYMENT_ID = __DEPLOYMENT_ID__;
}
}