Initial commit

2026-06-29 15:11:48 -07:00
commit 66dfdcc58d
404 changed files with 45970 additions and 0 deletions
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+import { spawnSync } from "node:child_process";
+import { mkdtempSync, rmSync, existsSync, readdirSync, chmodSync } from "node:fs";
+import { tmpdir } from "node:os";
+import { join } from "node:path";
+import { createServer } from "node:net";
+
+export type EphemeralPg = { url: string; stop: () => Promise<void> };
+
+/** Locate the newest installed PostgreSQL bin dir (e.g. /usr/lib/postgresql/16/bin). */
+function findPgBin(): string | null {
+  if (process.env.PG_BIN && existsSync(join(process.env.PG_BIN, "initdb"))) return process.env.PG_BIN;
+  const root = "/usr/lib/postgresql";
+  if (!existsSync(root)) return null;
+  const versions = readdirSync(root)
+    .filter((d) => /^\d+$/.test(d))
+    .sort((a, b) => Number(b) - Number(a));
+  for (const v of versions) {
+    const bin = join(root, v, "bin");
+    if (existsSync(join(bin, "initdb"))) return bin;
+  }
+  return null;
+}
+
+/** Whether we can stand up a throwaway Postgres here: root (to su to a non-root
+ *  user, since postgres refuses to run as root) + the binaries present. */
+export function canRunEphemeralPostgres(): boolean {
+  const isRoot = typeof process.getuid === "function" && process.getuid() === 0;
+  return isRoot && findPgBin() !== null;
+}
+
+function freePort(): Promise<number> {
+  return new Promise((resolve, reject) => {
+    const srv = createServer();
+    srv.listen(0, "127.0.0.1", () => {
+      const addr = srv.address();
+      const port = typeof addr === "object" && addr ? addr.port : 0;
+      srv.close(() => resolve(port));
+    });
+    srv.on("error", reject);
+  });
+}
+
+function sh(cmd: string): { ok: boolean; out: string } {
+  const r = spawnSync("bash", ["-lc", cmd], { encoding: "utf8" });
+  return { ok: r.status === 0, out: (r.stdout || "") + (r.stderr || "") };
+}
+
+/**
+ * Start a throwaway PostgreSQL instance for tests (no Docker required). initdb's a
+ * temp data dir, runs the server as a non-root user (`pgtest`) on a random loopback
+ * port with trust auth, and returns a connection URL + a stop()/cleanup. Use only
+ * after `canRunEphemeralPostgres()` returns true.
+ */
+export async function startEphemeralPostgres(): Promise<EphemeralPg> {
+  const pgbin = findPgBin();
+  if (!pgbin) throw new Error("no postgres binaries found");
+  const user = "pgtest";
+
+  // Ensure the non-root runner exists.
+  if (!sh(`id ${user}`).ok) {
+    const r = sh(`useradd -m -s /bin/bash ${user}`);
+    if (!sh(`id ${user}`).ok) throw new Error("could not create pgtest user: " + r.out);
+  }
+
+  const data = mkdtempSync(join(tmpdir(), "pgdata-"));
+  const sock = mkdtempSync(join(tmpdir(), "pgsock-"));
+  // The runner user must own the data + socket dirs.
+  chmodSync(data, 0o777);
+  chmodSync(sock, 0o777);
+  sh(`chown -R ${user} ${data} ${sock}`);
+
+  const init = sh(`su ${user} -c "${pgbin}/initdb -D ${data} -A trust -U postgres --no-sync"`);
+  if (!init.ok) {
+    rmSync(data, { recursive: true, force: true });
+    rmSync(sock, { recursive: true, force: true });
+    throw new Error("initdb failed: " + init.out.slice(-500));
+  }
+
+  const port = await freePort();
+  const start = sh(
+    `su ${user} -c "${pgbin}/pg_ctl -D ${data} -o '-p ${port} -k ${sock} -c listen_addresses=127.0.0.1' -w -l ${data}/server.log start"`,
+  );
+  if (!start.ok) {
+    const log = sh(`cat ${data}/server.log`).out;
+    rmSync(data, { recursive: true, force: true });
+    rmSync(sock, { recursive: true, force: true });
+    throw new Error("pg_ctl start failed: " + start.out + "\n" + log.slice(-500));
+  }
+
+  const url = `postgresql://postgres@127.0.0.1:${port}/postgres`;
+  const stop = async (): Promise<void> => {
+    sh(`su ${user} -c "${pgbin}/pg_ctl -D ${data} -w -m immediate stop"`);
+    rmSync(data, { recursive: true, force: true });
+    rmSync(sock, { recursive: true, force: true });
+  };
+  return { url, stop };
+}