astro/dist/core/server-islands/vite-plugin-server-islands.js

Astro is a modern site builder with web best practices, performance, and DX front-of-mind.

import { ASTRO_VITE_ENVIRONMENT_NAMES } from "../constants.js";
import { AstroError, AstroErrorData } from "../errors/index.js";
const SERVER_ISLAND_MANIFEST = "virtual:astro:server-island-manifest";
const RESOLVED_SERVER_ISLAND_MANIFEST = "\0" + SERVER_ISLAND_MANIFEST;
const serverIslandPlaceholderMap = "'$$server-islands-map$$'";
const serverIslandPlaceholderNameMap = "'$$server-islands-name-map$$'";
const SERVER_ISLAND_MAP_MARKER = "$$server-islands-map$$";
const serverIslandMapReplaceExp = /['"]\$\$server-islands-map\$\$['"]/g;
const serverIslandNameMapReplaceExp = /['"]\$\$server-islands-name-map\$\$['"]/g;
function vitePluginServerIslands({
  settings,
  serverIslandsState
}) {
  let command = "serve";
  let serverEnvironments = [];
  function ensureServerIslandReferenceIds(ctx) {
    for (const [resolvedPath, island] of serverIslandsState.getDiscoveredIslandEntries()) {
      if (serverIslandsState.hasReferenceId(resolvedPath)) continue;
      const referenceId = ctx.emitFile({
        type: "chunk",
        id: island.specifier,
        importer: island.importer,
        name: island.islandName
      });
      serverIslandsState.setReferenceId(resolvedPath, referenceId);
    }
  }
  return {
    name: "astro:server-islands",
    enforce: "post",
    config(_config, { command: _command }) {
      command = _command;
    },
    buildStart() {
      if (command !== "build" || this.environment?.name !== ASTRO_VITE_ENVIRONMENT_NAMES.ssr) {
        return;
      }
      ensureServerIslandReferenceIds(this);
    },
    configureServer(server) {
      serverEnvironments = [];
      for (const name of [
        ASTRO_VITE_ENVIRONMENT_NAMES.ssr,
        ASTRO_VITE_ENVIRONMENT_NAMES.prerender,
        ASTRO_VITE_ENVIRONMENT_NAMES.astro
      ]) {
        const env = server.environments[name];
        if (env) {
          serverEnvironments.push(env);
        }
      }
    },
    resolveId: {
      filter: {
        id: new RegExp(`^${SERVER_ISLAND_MANIFEST}$`)
      },
      handler() {
        return RESOLVED_SERVER_ISLAND_MANIFEST;
      }
    },
    load: {
      filter: {
        id: new RegExp(`^${RESOLVED_SERVER_ISLAND_MANIFEST}$`)
      },
      handler() {
        return {
          code: `export const serverIslandMap = ${serverIslandPlaceholderMap};

export const serverIslandNameMap = ${serverIslandPlaceholderNameMap};`
        };
      }
    },
    transform: {
      filter: {
        id: {
          include: [/\.(astro|mdx)$/, new RegExp(`^${RESOLVED_SERVER_ISLAND_MANIFEST}$`)]
        }
      },
      async handler(_code, id) {
        const info = this.getModuleInfo(id);
        const astro = info ? info.meta.astro : void 0;
        const isBuildSsr = command === "build" && this.environment?.name === ASTRO_VITE_ENVIRONMENT_NAMES.ssr;
        if (astro) {
          for (const comp of astro.serverComponents) {
            if (!settings.adapter) {
              throw new AstroError(AstroErrorData.NoAdapterInstalledServerIslands);
            }
            const island = serverIslandsState.discover({
              resolvedPath: comp.resolvedPath,
              localName: comp.localName,
              specifier: comp.specifier ?? comp.resolvedPath,
              importer: id
            });
            if (isBuildSsr && !serverIslandsState.hasReferenceId(comp.resolvedPath)) {
              const referenceId = this.emitFile({
                type: "chunk",
                id: island.specifier,
                importer: island.importer,
                name: island.islandName
              });
              serverIslandsState.setReferenceId(comp.resolvedPath, referenceId);
            }
          }
        }
        if (serverIslandsState.hasIslands()) {
          for (const env of serverEnvironments) {
            const mod = env.moduleGraph.getModuleById(RESOLVED_SERVER_ISLAND_MANIFEST);
            if (mod) {
              env.moduleGraph.invalidateModule(mod);
            }
          }
        }
        if (id === RESOLVED_SERVER_ISLAND_MANIFEST) {
          if (command === "build" && settings.buildOutput) {
            const hasServerIslands = serverIslandsState.hasIslands();
            if (hasServerIslands && settings.buildOutput !== "server") {
              throw new AstroError(AstroErrorData.NoAdapterInstalledServerIslands);
            }
          }
          if (command !== "build" && serverIslandsState.hasIslands()) {
            const mapSource = serverIslandsState.createImportMapSourceFromDiscovered(
              (fileName) => fileName
            );
            const nameMapSource = serverIslandsState.createNameMapSource();
            return {
              code: `
						export const serverIslandMap = ${mapSource};

						export const serverIslandNameMap = ${nameMapSource};
						`
            };
          }
        }
      }
    },
    renderChunk(code, chunk) {
      if (!code.includes(SERVER_ISLAND_MAP_MARKER)) return;
      if (command === "build") {
        const envName = this.environment?.name;
        let mapSource;
        if (envName === ASTRO_VITE_ENVIRONMENT_NAMES.ssr) {
          const isRelativeChunk = !chunk.isEntry;
          const dots = isRelativeChunk ? ".." : ".";
          mapSource = serverIslandsState.createImportMapSourceFromReferences(
            (referenceId) => this.getFileName(referenceId),
            (fileName) => `${dots}/${fileName}`
          );
        } else {
          mapSource = serverIslandsState.createImportMapSourceFromDiscovered(
            (fileName) => fileName
          );
        }
        const nameMapSource = serverIslandsState.createNameMapSource();
        return {
          code: code.replace(serverIslandMapReplaceExp, mapSource).replace(serverIslandNameMapReplaceExp, nameMapSource),
          map: null
        };
      }
      return {
        code: code.replace(serverIslandMapReplaceExp, "new Map();").replace(serverIslandNameMapReplaceExp, "new Map()"),
        map: null
      };
    }
  };
}
export {
  SERVER_ISLAND_MANIFEST,
  SERVER_ISLAND_MAP_MARKER,
  vitePluginServerIslands
};