Fix dev migration prompt and embedded db:migrate

packages/db/src/migration-runtime.ts

@@ -0,0 +1,134 @@
+import { existsSync, readFileSync, rmSync } from "node:fs";
+import { createRequire } from "node:module";
+import path from "node:path";
+import { fileURLToPath, pathToFileURL } from "node:url";
+import { ensurePostgresDatabase } from "./client.js";
+import { resolveDatabaseTarget } from "./runtime-config.js";
+
+type EmbeddedPostgresInstance = {
+  initialise(): Promise<void>;
+  start(): Promise<void>;
+  stop(): Promise<void>;
+};
+
+type EmbeddedPostgresCtor = new (opts: {
+  databaseDir: string;
+  user: string;
+  password: string;
+  port: number;
+  persistent: boolean;
+  onLog?: (message: unknown) => void;
+  onError?: (message: unknown) => void;
+}) => EmbeddedPostgresInstance;
+
+export type MigrationConnection = {
+  connectionString: string;
+  source: string;
+  stop: () => Promise<void>;
+};
+
+function readRunningPostmasterPid(postmasterPidFile: string): number | null {
+  if (!existsSync(postmasterPidFile)) return null;
+  try {
+    const pid = Number(readFileSync(postmasterPidFile, "utf8").split("\n")[0]?.trim());
+    if (!Number.isInteger(pid) || pid <= 0) return null;
+    process.kill(pid, 0);
+    return pid;
+  } catch {
+    return null;
+  }
+}
+
+function readPidFilePort(postmasterPidFile: string): number | null {
+  if (!existsSync(postmasterPidFile)) return null;
+  try {
+    const lines = readFileSync(postmasterPidFile, "utf8").split("\n");
+    const port = Number(lines[3]?.trim());
+    return Number.isInteger(port) && port > 0 ? port : null;
+  } catch {
+    return null;
+  }
+}
+
+async function loadEmbeddedPostgresCtor(): Promise<EmbeddedPostgresCtor> {
+  const require = createRequire(import.meta.url);
+  const resolveCandidates = [
+    path.resolve(fileURLToPath(new URL("../..", import.meta.url))),
+    path.resolve(fileURLToPath(new URL("../../server", import.meta.url))),
+    path.resolve(fileURLToPath(new URL("../../cli", import.meta.url))),
+    process.cwd(),
+  ];
+
+  try {
+    const resolvedModulePath = require.resolve("embedded-postgres", { paths: resolveCandidates });
+    const mod = await import(pathToFileURL(resolvedModulePath).href);
+    return mod.default as EmbeddedPostgresCtor;
+  } catch {
+    throw new Error(
+      "Embedded PostgreSQL support requires dependency `embedded-postgres`. Reinstall dependencies and try again.",
+    );
+  }
+}
+
+async function ensureEmbeddedPostgresConnection(
+  dataDir: string,
+  preferredPort: number,
+): Promise<MigrationConnection> {
+  const EmbeddedPostgres = await loadEmbeddedPostgresCtor();
+  const postmasterPidFile = path.resolve(dataDir, "postmaster.pid");
+  const runningPid = readRunningPostmasterPid(postmasterPidFile);
+  const runningPort = readPidFilePort(postmasterPidFile);
+
+  if (runningPid) {
+    const port = runningPort ?? preferredPort;
+    const adminConnectionString = `postgres://paperclip:paperclip@127.0.0.1:${port}/postgres`;
+    await ensurePostgresDatabase(adminConnectionString, "paperclip");
+    return {
+      connectionString: `postgres://paperclip:paperclip@127.0.0.1:${port}/paperclip`,
+      source: `embedded-postgres@${port}`,
+      stop: async () => {},
+    };
+  }
+
+  const instance = new EmbeddedPostgres({
+    databaseDir: dataDir,
+    user: "paperclip",
+    password: "paperclip",
+    port: preferredPort,
+    persistent: true,
+    onLog: () => {},
+    onError: () => {},
+  });
+
+  if (!existsSync(path.resolve(dataDir, "PG_VERSION"))) {
+    await instance.initialise();
+  }
+  if (existsSync(postmasterPidFile)) {
+    rmSync(postmasterPidFile, { force: true });
+  }
+  await instance.start();
+
+  const adminConnectionString = `postgres://paperclip:paperclip@127.0.0.1:${preferredPort}/postgres`;
+  await ensurePostgresDatabase(adminConnectionString, "paperclip");
+
+  return {
+    connectionString: `postgres://paperclip:paperclip@127.0.0.1:${preferredPort}/paperclip`,
+    source: `embedded-postgres@${preferredPort}`,
+    stop: async () => {
+      await instance.stop();
+    },
+  };
+}
+
+export async function resolveMigrationConnection(): Promise<MigrationConnection> {
+  const target = resolveDatabaseTarget();
+  if (target.mode === "postgres") {
+    return {
+      connectionString: target.connectionString,
+      source: target.source,
+      stop: async () => {},
+    };
+  }
+
+  return ensureEmbeddedPostgresConnection(target.dataDir, target.port);
+}