DDRCompanion/lib/db/db.worker.ts

import sqlWasmUrl from "@jlongster/sql.js/dist/sql-wasm.wasm?url";
import { MigrateDeploy } from "@prisma/migrate";
import initSqlJs from "@jlongster/sql.js";
import { SQLiteFS } from "absurd-sql";
import type { BindParams, Database } from "sql.js";
import IndexedDBBackend from "absurd-sql/dist/indexeddb-backend";
import { RpcProvider } from "worker-rpc";
import executeMigrations from "./migrations";
import { DbStatusCode } from "./constants";

async function init() {
  const rpcProvider = new RpcProvider((message, transfer) =>
    self.postMessage(message, undefined, transfer),
  );
  self.addEventListener("message", (evt) => rpcProvider.dispatch(evt.data));

  const SQL = await initSqlJs({
    locateFile: (file) => {
      switch (file) {
        case "sql-wasm.wasm":
          return sqlWasmUrl;
      }
      return file;
    },
  });

  rpcProvider.signal("db", { status: DbStatusCode.LOADED_SQLITE });

  const sqlFS = new SQLiteFS(SQL.FS, new IndexedDBBackend());
  SQL.register_for_idb(sqlFS);

  SQL.FS.mkdir("/sql");
  SQL.FS.mount(sqlFS, {}, "/sql");

  const path = "/sql/db.sqlite";
  if (typeof SharedArrayBuffer === "undefined") {
    const stream = SQL.FS.open(path, "a+");
    await stream.node.contents.readIfFallback();
    SQL.FS.close(stream);
  }

  const db: Database = new SQL.Database(path, { filename: true });
  db.exec("PRAGMA journal_mode=MEMORY;");

  rpcProvider.signal("db", { status: DbStatusCode.OPENED_DATABASE });

  await executeMigrations(db);

  rpcProvider.signal("db", { status: DbStatusCode.RAN_MIGRATIONS });

  rpcProvider.registerRpcHandler("run", ({ s, p }: Args) => db.run(s, p));

  rpcProvider.registerRpcHandler("exec", ({ s, p }: Args) => db.exec(s, p));

  rpcProvider.signal("db", { status: DbStatusCode.READY });
}

init();

interface Args {
  s: string;
  p?: BindParams;
}