prepareDB.js

require('dotenv').config()
require('../src/utils/aws').setupAWS()
const _ = require('lodash')

const AWS = require('aws-sdk')

const { TABLES_PARAMS } = require('../src/constants/db')
const migrations = require('../src/migrations')

const prepareDB = async () => {
  const database = new AWS.DynamoDB()
  const neededTables = TABLES_PARAMS.map(({ TableName }) => TableName)
  const existingTables = await database
    .listTables()
    .promise()
    .then(data => data.TableNames)
  const dbsToDelete = _.without(existingTables, ...neededTables)
  const dbsToCreate = _.without(neededTables, ...existingTables)

  await Promise.all(
    dbsToDelete.map(TableName =>
      database.deleteTable({ TableName }).promise()
    )
  )
  await Promise.all(
    dbsToCreate.map(TableName =>
      database
        .createTable(TABLES_PARAMS.find(t => t.TableName === TableName))
        .promise()
    )
  )

  const documentClient = new AWS.DynamoDB.DocumentClient()

  const migration = await documentClient
    .get({
      TableName: 'Management',
      Key: { id: 'migration' }
    })
    .promise()
    .then(({ Item }) => Item)

  if (
    migration.lastMigration !== undefined &&
    migration.lastMigration < migrations.length
  ) {
    const migrationsToRun = migrations.slice(migration.lastMigration + 1)
    await Promise.all(migrationsToRun.map(migration => migration()))
  }

  await documentClient
    .put({
      TableName: 'Management',
      Item: {
        id: 'migration',
        lastMigration: migrations.length - 1
      }
    })
    .promise()
}

prepareDB()