queryWrapper

gistfile1.txt

import crypto from 'crypto'
import redis from 'services/redis'

export async function queryWrapper (query, ttl) {
  // these could also be passed explicitly to the function, but that may leave more room for error?
  let table, method
  query.modify(qb => {
    table = qb._table || 'some_fallback'
    method = qb._method
  })

  // if this is a SELECT query, attempt to read/write from cache
  if (method === 'select' || method === 'first') {
    const hashedQuery = crypto.createHash('md5').update(query.toString()).digest('hex')
    const cached = redis.get(`${table}:${hashedQuery}`)
    if (cached) return JSON.parse(cached)
  
    const queryResult = await query
    redis.set(`${table}:${hashedQuery}`, JSON.stringify(queryResult))
    if (ttl) redis.expire(`${table}:${hashedQuery}`, ttl)
    return queryResult
  }
  
  // if this isn't a SELECT query, invalidate all keys for this table
  const keys = await redis.keys(`${table}:`)
  await redis.del(keys)
  return query
}