【Firebase】CLI 経由で Firestore に大量のテストデータを投入する

$ yarn add ts-node faker commander

functions
└── cli
    ├── index.ts
    └── user.ts

{
  "scripts": {
    "cli": "ts-node cli/index.ts"
  }
}

import * as admin from 'firebase-admin'
import * as faker from 'faker'

// 共通化するために Admin SDK の初期化は index.ts で行う
const db = admin.firestore()
const batchSize = 500

// 作成用関数
export const createUsers = async (n: number) => {
  const usersRef = await db.collection('users')

  // 再帰関数
  const excuteBatch = async (size: number) => {
    if (size === 0) {
      return
    }
    // 500件を超えないようにする
    const length = Math.min(size, batchSize)
    const batch = db.batch()
    for (let i = 0; i < length; i = i + 1) {
      const user = {
        firstName: faker.name.firstName(),
        lastName: faker.name.lastName(),
        createdAt: admin.firestore.FieldValue.serverTimestamp(),
        updatedAt: admin.firestore.FieldValue.serverTimestamp(),
        isMock: true // 削除時のクエリ用フィールド
      }
      batch.create(usersRef.doc(), user)
    }
    const results = await batch.commit()
    // 書き込みが成功した分を引いた残りの件数を代入
    await excuteBatch(size - results.length)
  }
  await excuteBatch(n)
}

// 削除用関数
export const deleteUsers = async () => {
  // モックデータのみを500件ずつ取得
  const query = await db
    .collection('users')
    .where('isMock', '==', true)
    .limit(batchSize)

  // 再帰関数
  const executeBatch = async () => {
    const snapshot = await query.get()
    if (snapshot.size === 0) {
      return
    }
    const batch = db.batch()
    snapshot.docs.forEach(doc => {
      batch.delete(doc.ref)
    })
    await batch.commit()
    await executeBatch()
  }
  await executeBatch()
}

import * as admin from 'firebase-admin'
import * as program from 'commander'

// user.ts を import する前に Admin SDK を初期化する
admin.initializeApp()
admin.firestore().settings({ timestampsInSnapshots: true })

import { createUsers, deleteUsers } from './user'

program.version('1.0.0', '-v, --version')
program
  .command('user')
  .option('-d, --delete', 'delete only the created documents')
  .option('-n, --number <n>', 'A number of test documents', parseInt, 0)
  .description('create test user documents')
  .action(cmd => {
    if (cmd.number > 10000) {
      return console.error('The number must be 10000 or less')
    }
    const promise = cmd.delete ? deleteUsers() : createUsers(cmd.number)
    promise.then(() => console.log('Command has completed')).catch(console.error)
  })
program.parse(process.argv)

console.log('Firestore Mocking CLI')

$ yarn cli user -n 1000

yarn run v1.12.3
$ ts-node test/cli.ts user -n 1000
Firestore Mocking CLI
Command has completed
✨  Done in 6.71s.

$ yarn cli user -d

yarn run v1.12.3
$ ts-node test/cli.ts user -d
Firestore Mocking CLI
Command has completed
✨  Done in 5.73s.