Link Write Journal

1'use strict';
2
3const fs = require('node:fs/promises');
4const path = require('node:path');
5const { createHash } = require('node:crypto');
6
7function createLinkWriteJournal(projectDir, runId) {
8  const root = path.join(projectDir, 'execution', 'link-write-journal');
9  const filename = (recordId, intentKey) => path.join(root, `${createHash('sha256').update([runId, recordId, intentKey].join('\0')).digest('hex')}.json`);
10  const save = async (file, row) => {
11    await fs.mkdir(root, { recursive: true });
12    const temporary = `${file}.${process.pid}.tmp`;
13    await fs.writeFile(temporary, `${JSON.stringify(row, null, 2)}\n`);
14    await fs.rename(temporary, file);
15  };
16  return {
17    async findCompleted(recordId, intentKey) {
18      try {
19        const row = JSON.parse(await fs.readFile(filename(recordId, intentKey), 'utf8'));
20        return row.status === 'complete' ? row : null;
21      } catch (error) { if (error.code === 'ENOENT') return null; throw error; }
22    },
23    async findOpen(recordId, intentKey) {
24      try {
25        const row = JSON.parse(await fs.readFile(filename(recordId, intentKey), 'utf8'));
26        return row.status === 'open' ? row : null;
27      } catch (error) { if (error.code === 'ENOENT') return null; throw error; }
28    },
29    async start(recordId, baseRevision, changes, intentKey) {
30      if (!intentKey) throw new Error('link write intent key required');
31      const file = filename(recordId, intentKey);
32      const row = { runId, recordId, intentKey, baseRevision, changes, status: 'open' };
33      await save(file, row);
34      return row;
35    },
36    async complete(row) {
37      await save(filename(row.recordId, row.intentKey), { ...row, status: 'complete', completedAt: new Date().toISOString() });
38    },
39  };
40}
41
42module.exports = { createLinkWriteJournal };