levelup

cache.ts

/**
 * @file: cache.ts
 */
// Import levelup dependencies manually.
var levelup = require('levelup')
var leveljs = require('level-js')
var ttl     = require('level-ttl')

// Instantiate store.
var db = levelup(leveljs('/tmp/mydb.db'))

// Try setting up global ttl (also supports per-item ttl)
db = ttl(db, { checkFrequency: 1000 })

// Set cache.
export const cache_get = async (cid: string, $bin = 'cache') => {
  // https://github.com/Level/level-js#type-support
  return await db.get(cid, { asBuffer: false })
}

// Get cache.
export const cache_set = (cid:string, data:string, expire:number = CACHE_PERMANENT) => {
  console.log('Setting cache cid "' + cid + '" to expire in ' + expire + ' milliseconds')

  // todo automatically serialize data if required.
  db.put(cid, data, { ttl: expire }, err => {
    if(err) console.log(err)
  })
}