Add database utility functions

src/db.ts

@@ -0,0 +1,30 @@
+import { randomBytes } from "crypto";
+import { Pool, PoolClient } from "pg";
+
+const pool = new Pool();
+
+export function connect(): Promise<PoolClient> {
+  return pool.connect();
+}
+
+export function generateId(): bigint {
+  const buf = randomBytes(8);
+
+  buf[0] &= 0x7f; // Force number to be non-negative
+
+  // Let's not depend on Node v12 for the sake of 3 LoC just yet.
+
+  const hi = buf.readUInt32BE(0);
+  const lo = buf.readUInt32BE(4);
+
+  return (BigInt(hi) << 32n) | BigInt(lo);
+}
+
+/** Generate a random 32-bit ID for use in external protocol messages */
+export function generateExtId(): number {
+  const buf = randomBytes(4);
+
+  buf[0] &= 0x7f; // Force number to be non-negative
+
+  return buf.readUInt32BE(0);
+}