feat: add persistent store, atomic 0600 writes

src/config/store.ts

@@ -0,0 +1,50 @@
+import { existsSync, mkdirSync, readFileSync, renameSync, writeFileSync } from 'node:fs'
+import { homedir } from 'node:os'
+import { dirname, join } from 'node:path'
+import { type ConnectionConfig, connectionConfigSchema } from './types.js'
+
+export const defaultStorePath = (env: NodeJS.ProcessEnv = process.env): string =>
+    env.DBMOLE_STORE ?? join(homedir(), '.config', 'dbmole', 'connections.json')
+
+export const parseConnections = (items: unknown[], origin: string): ConnectionConfig[] => {
+    const result: ConnectionConfig[] = []
+    for (const item of items) {
+        const check = connectionConfigSchema.safeParse(item)
+        if (check.success) {
+            result.push(check.data)
+        } else {
+            const name = (item as { name?: unknown })?.name ?? '<unnamed>'
+            console.error(`dbmole: skipping invalid connection '${String(name)}' from ${origin}`)
+        }
+    }
+    return result
+}
+
+export const readStore = (path: string): ConnectionConfig[] => {
+    mkdirSync(dirname(path), { recursive: true, mode: 0o700 })
+    if (!existsSync(path)) return []
+    let parsed: unknown
+    try {
+        parsed = JSON.parse(readFileSync(path, 'utf8'))
+    } catch {
+        console.error(`dbmole: store file ${path} is not valid JSON, treating as empty`)
+        return []
+    }
+    if (!Array.isArray(parsed)) {
+        console.error(`dbmole: store file ${path} must contain a JSON array, treating as empty`)
+        return []
+    }
+    return parseConnections(parsed, `store ${path}`)
+}
+
+let writeSeq = 0
+
+export const writeStore = (path: string, connections: ConnectionConfig[]): void => {
+    mkdirSync(dirname(path), { recursive: true, mode: 0o700 })
+    writeSeq += 1
+    const tmp = `${path}.${process.pid}.${writeSeq}.tmp`
+    const items = connections.map((c) => JSON.stringify(c, null, 4))
+    const content = items.length === 0 ? '[]\n' : `[\n${items.join(',\n')}\n]\n`
+    writeFileSync(tmp, content, { mode: 0o600 })
+    renameSync(tmp, path)
+}

test/unit/config/store.test.ts

@@ -0,0 +1,91 @@
+import {
+    mkdirSync,
+    mkdtempSync,
+    readdirSync,
+    readFileSync,
+    rmSync,
+    statSync,
+    writeFileSync
+} from 'node:fs'
+import { tmpdir } from 'node:os'
+import { join } from 'node:path'
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+import { defaultStorePath, readStore, writeStore } from '../../../src/config/store.js'
+import type { ConnectionConfig } from '../../../src/config/types.js'
+
+const connection: ConnectionConfig = {
+    name: 'lab',
+    type: 'postgres',
+    host: 'localhost',
+    user: 'postgres',
+    readonly: false
+}
+
+describe('store', () => {
+    let dir: string
+    let path: string
+
+    beforeEach(() => {
+        dir = mkdtempSync(join(tmpdir(), 'dbmole-store-'))
+        path = join(dir, 'nested', 'connections.json')
+        vi.spyOn(console, 'error').mockImplementation(() => {})
+    })
+
+    afterEach(() => {
+        rmSync(dir, { recursive: true, force: true })
+        vi.restoreAllMocks()
+    })
+
+    it('reads missing file as empty list', () => {
+        expect(readStore(path)).toEqual([])
+    })
+
+    it('round-trips connections and creates parent dirs', () => {
+        writeStore(path, [connection])
+        expect(readStore(path)).toEqual([connection])
+    })
+
+    it('writes file with 0600 permissions and leaves no tmp files', () => {
+        writeStore(path, [connection])
+        const mode = statSync(path).mode & 0o777
+        expect(mode).toBe(0o600)
+        const leftovers = readdirSync(join(dir, 'nested')).filter((f) => f.includes('.tmp'))
+        expect(leftovers).toEqual([])
+    })
+
+    it('treats invalid JSON as empty with a warning', () => {
+        writeStore(path, [connection])
+        writeFileSync(path, '{ broken')
+        expect(readStore(path)).toEqual([])
+        expect(console.error).toHaveBeenCalled()
+    })
+
+    it('treats non-array JSON as empty with a warning', () => {
+        writeStore(path, [connection])
+        writeFileSync(path, '{"connections": []}')
+        expect(readStore(path)).toEqual([])
+        expect(console.error).toHaveBeenCalled()
+    })
+
+    it('skips invalid entries but keeps valid ones', () => {
+        mkdirSync(join(dir, 'nested'), { recursive: true })
+        writeFileSync(path, JSON.stringify([connection, { name: 'broken' }]))
+        expect(readStore(path)).toEqual([connection])
+        expect(console.error).toHaveBeenCalled()
+    })
+
+    it('stores pretty JSON for hand editing', () => {
+        writeStore(path, [connection])
+        expect(readFileSync(path, 'utf8')).toContain('\n    "name": "lab"')
+    })
+})
+
+describe('defaultStorePath', () => {
+    it('honors DBMOLE_STORE override', () => {
+        expect(defaultStorePath({ DBMOLE_STORE: '/tmp/custom.json' })).toBe('/tmp/custom.json')
+    })
+
+    it('falls back to ~/.config/dbmole/connections.json', () => {
+        expect(defaultStorePath({})).toMatch(/\.config\/dbmole\/connections\.json$/)
+    })
+})