Write back to Options within plugin?

[bruceharrison1984]

Is it possible to write back to the Options object within a plugin? My simple example spins up a secondary server, and then I want to apply DevServer proxy configuration once I know what the server address is.

class MiniflarePlugin implements RspackPluginInstance {
    PLUGIN_NAME = 'MiniflareServer';

    async apply(compiler: Compiler) {
        if (!compiler.watchMode) return;
        const miniflare = await unstable_dev(
            './functions/index.ts',
            { experimental: { liveReload: true, testMode: false }, port: 8888 },
        );

        compiler.options.devServer = {
            proxy: [
                {
                    context: ['/api'],
                    router: () => `http://${miniflare?.address}:${miniflare?.port}`,
                    logLevel: 'error',
                    secure: false,
                    changeOrigin: true,
                },
            ]
        }
    }
}

However, this doesn't work. If I assign static values upfront via rsbuild.config.ts it works as expected. I know other frameworks like Vite allow you to do this (I'm porting from Vite where I wrote a similar plugin).

I combed through the docs and didn't find anything that addressed this situation, and all plugin methods appear to return void, so passing the Options back out from apply doesn't seem the correct path.

[bruceharrison1984]

I needed to use an rsbuild plugin instead of an rspack plugin, as well as set the --mode argument when running dev mode. All working now!

const PLUGIN_NAME = 'MiniflareServer';
import type {
  RsbuildPlugin,
  RsbuildPluginAPI,
} from '@rsbuild/core';
import { unstable_dev } from 'wrangler';

const PLUGIN_NAME = 'MiniflareServer';

class MiniflarePlugin implements RsbuildPlugin {
  name = PLUGIN_NAME;

  setup(api: RsbuildPluginAPI) {
    api.modifyRsbuildConfig({
      order: 'post',
      handler: async (config, { mergeRsbuildConfig }) => {
        if (config.mode !== 'development') return;

        const miniflare = await unstable_dev('./functions/index.ts', {
          experimental: { liveReload: true, testMode: false },
          port: 8888,
        });

        return mergeRsbuildConfig(config, {
          server: {
            proxy: [
              {
                context: ['/api'],
                router: () => `http://${miniflare?.address}:${miniflare?.port}`,
                logLevel: 'error',
                secure: false,
                changeOrigin: true,
              },
            ],
          },
        });
      },
    });
  }
}

export const miniflarePlugin = () => new MiniflarePlugin();