feat: allow overriding platform proxy environment

Author: Juul

.changeset/shaggy-bobcats-battle.md

@@ -14,4 +14,4 @@ initOpenNextCloudflareForDev({
 });
 ```
 
-You can find the type with the available options [here](https://github.com/cloudflare/workers-sdk/blob/main/packages/wrangler/src/api/integrations/platform/index.ts#L32) in the Wrangler source code. Please note that the `environment` field is not customizable as it's used internally by OpenNext.js. If you have a use case where overriding `environment` is necessary, please let us know by opening a [feature request](https://github.com/cloudflare/workers-sdk/issues).
+You can find the configuration type with it's available options [here](https://github.com/cloudflare/workers-sdk/blob/main/packages/wrangler/src/api/integrations/platform/index.ts#L32) in the Wrangler source code.

packages/cloudflare/src/api/cloudflare-context.ts

@@ -210,10 +210,17 @@ async function getCloudflareContextAsync<
  * Note: this function should only be called inside the Next.js config file, and although async it doesn't need to be `await`ed
  * @param options options on how the function should operate and if/where to persist the platform data
  */
-export async function initOpenNextCloudflareForDev(options?: Omit<GetPlatformProxyOptions, "environment">) {
+export async function initOpenNextCloudflareForDev(options?: GetPlatformProxyOptions) {
   const shouldInitializationRun = shouldContextInitializationRun();
   if (!shouldInitializationRun) return;
 
+  if (options?.environment && process.env.NEXT_DEV_WRANGLER_ENV) {
+    console.warn(
+      `'initOpenNextCloudflareForDev' has been called with an environment option while NEXT_DEV_WRANGLER_ENV is set.` +
+        ` NEXT_DEV_WRANGLER_ENV will be ignored and the environment will be set to: '${options.environment}'`
+    );
+  }
+
   const context = await getCloudflareContextFromWrangler(options);
 
   addCloudflareContextToNodejsGlobal(context);
@@ -293,13 +300,16 @@ async function monkeyPatchVmModuleEdgeContext(cloudflareContext: CloudflareConte
 async function getCloudflareContextFromWrangler<
   CfProperties extends Record<string, unknown> = IncomingRequestCfProperties,
   Context = ExecutionContext,
->(options?: Omit<GetPlatformProxyOptions, "environment">): Promise<CloudflareContext<CfProperties, Context>> {
+>(options?: GetPlatformProxyOptions): Promise<CloudflareContext<CfProperties, Context>> {
   // Note: we never want wrangler to be bundled in the Next.js app, that's why the import below looks like it does
   const { getPlatformProxy } = await import(/* webpackIgnore: true */ `${"__wrangler".replaceAll("_", "")}`);
+
+  // This allows the selection of a wrangler environment while running in next dev mode
+  const environment = options?.environment ?? process.env.NEXT_DEV_WRANGLER_ENV;
+
   const { env, cf, ctx } = await getPlatformProxy({
-    // This allows the selection of a wrangler environment while running in next dev mode
     ...options,
-    environment: process.env.NEXT_DEV_WRANGLER_ENV,
+    environment,
   });
   return {
     env,