rwsdk/dist/vite/transformServerReferences.mjs

Build fast, server-driven webapps on Cloudflare with SSR, RSC, and realtime

import { relative } from "node:path";
import MagicString from "magic-string";
import debug from "debug";
import { parse } from "es-module-lexer";
import { ensureNoSSRNamespace, ensureSSRNamespace, } from "./virtualizedSSRPlugin.mjs";
const logVite = debug("rwsdk:vite:transform-server-references:vite");
const logEsbuild = debug("rwsdk:vite:transform-server-references:esbuild");
export async function transformServerReferences(code, id, env) {
    const log = env.isEsbuild ? logEsbuild : logVite;
    log("Called transformServerReferences for id: id=%s, env: %O", id, env);
    // Only transform files that start with 'use server'
    const cleanCode = code.trimStart();
    const hasUseServer = cleanCode.startsWith('"use server"') ||
        cleanCode.startsWith("'use server'");
    if (!hasUseServer) {
        log("Skipping: no 'use server' directive in id=%s", id);
        return;
    }
    log("Processing 'use server' module: id=%s", id);
    // Remove all 'use server' directives
    let s = new MagicString(code);
    s.replaceAll("'use server'", "");
    s.replaceAll('"use server"', "");
    s.trim();
    // Parse exports
    await import("es-module-lexer"); // ensure parse is initialized
    const [_, exports] = parse(code);
    log("Parsed exports for id=%s: %O", id, exports);
    // Compute relativeId for registration
    let relativeId = id;
    if (env.topLevelRoot) {
        try {
            relativeId = `/${relative(env.topLevelRoot, id)}`;
            log("Computed relativeId for id=%s: %s", id, relativeId);
        }
        catch (e) {
            log("Error computing relativeId for id=%s: %O", id, e);
        }
    }
    let importLines = [];
    let exportLines = [];
    if (env.isSSR) {
        log("SSR import detected for id=%s", id);
        // Just re-export everything from the original module in SSR
        importLines.push(`export * from ${JSON.stringify(ensureNoSSRNamespace(id))};`);
        exportLines = [];
    }
    else if (env.environmentName === "worker") {
        log("Worker environment detected for id=%s", id);
        importLines.push('import { registerServerReference } from "rwsdk/worker";');
        importLines.push(`import ${JSON.stringify(ensureSSRNamespace(id))};`);
        for (const e of exports) {
            log("Registering server reference for export: %O in id=%s", e, id);
            exportLines.push(`registerServerReference(${e.ln}, ${JSON.stringify(relativeId)}, ${JSON.stringify(e.ln)});`);
        }
    }
    else if (env.environmentName === "client") {
        log("Client environment detected for id=%s", id);
        importLines.push('import { createServerReference } from "rwsdk/client";');
        for (const e of exports) {
            log("Creating client server reference for export: %O in id=%s", e, id);
            exportLines.push(`export const ${e.ln} = createServerReference(${JSON.stringify(relativeId)}, ${JSON.stringify(e.ln)});`);
        }
    }
    log("Processing complete for id=%s", id);
    const result = [...importLines, ...exportLines].join("\n");
    if (process.env.VERBOSE) {
        log(":VERBOSE: Transformed code for id=%s:\n%s", id, result);
    }
    return {
        code: result + "\n",
        map: s.generateMap({ hires: true }),
    };
}