Events Example Test

1import { describe, expect, it } from "vitest";
2import { query } from "./clickhouse.js";
3import { Cursor } from "../src/readers/core.js";
4import { type EventRow, readEventRow } from "../src/examples/events.js";
5import { readRows } from "../src/readers/rows.js";
6
7/**
8 * Runs the `events` example end to end: CREATE a table, populate it (here via
9 * `JSONEachRow` — an INSERT carries its rows in the same HTTP body after the
10 * FORMAT clause), SELECT it back `FORMAT RowBinary`, and decode with the reader
11 * imported from `src/examples/events.ts`. ENGINE = Memory + a finally-drop keeps
12 * re-runs clean; the SELECT's ORDER BY gives a stable order to assert against.
13 */
14describe("example: events (scalars via JSONEachRow)", () => {
15  it("creates, populates, and reads back through readEventRow", async () => {
16    const t = "rb_example_events";
17    await query(`DROP TABLE IF EXISTS ${t}`);
18    await query(
19      `CREATE TABLE ${t} (id UInt64, name String, ts DateTime('UTC')) ENGINE = Memory`,
20    );
21    try {
22      const rows = [
23        { id: 1, name: "alpha", ts: "2021-01-01 00:00:00" },
24        { id: 2, name: "bravo", ts: "2021-06-15 12:30:00" },
25        { id: 3, name: "", ts: "1970-01-01 00:00:00" },
26      ];
27      await query(
28        `INSERT INTO ${t} FORMAT JSONEachRow\n` +
29          rows.map((r) => JSON.stringify(r)).join("\n"),
30      );
31
32      const r = new Cursor(
33        await query(
34          `SELECT id, name, ts FROM ${t} ORDER BY id FORMAT RowBinary`,
35        ),
36      );
37      const out: EventRow[] = readRows(readEventRow)(r);
38      expect(out).toEqual([
39        { id: 1n, name: "alpha", ts: "2021-01-01T00:00:00.000Z" },
40        { id: 2n, name: "bravo", ts: "2021-06-15T12:30:00.000Z" },
41        { id: 3n, name: "", ts: "1970-01-01T00:00:00.000Z" },
42      ]);
43      expect(r.pos).toBe(r.buf.length);
44    } finally {
45      await query(`DROP TABLE IF EXISTS ${t}`);
46    }
47  });
48});