feat: create db table and store operator id

lib/middlewares/operatorId.js

@@ -1,34 +1,15 @@
-const pify = require('pify')
-const fs = pify(require('fs'))
-const hkdf = require('futoin-hkdf')
-
-const state = require('./state')
-const mnemonicHelpers = require('../mnemonic-helpers')
-const options = require('../options')
-const logger = require('../logger')
-
-function computeOperatorId (masterSeed) {
-  return hkdf(masterSeed, 16, { salt: 'lamassu-server-salt', info: 'operator-id' }).toString('hex')
-}
-
-function getMnemonic () {
-  if (state.mnemonic) return Promise.resolve(state.mnemonic)
-  return fs.readFile(options.mnemonicPath, 'utf8').then(mnemonic => {
-    state.mnemonic = mnemonic
-    return mnemonic
-  })
-}
+const { getOperatorId } = require('../operator')
 
 function findOperatorId (req, res, next) {
-  return getMnemonic().then(mnemonic => {
-    return computeOperatorId(mnemonicHelpers.toEntropyBuffer(mnemonic))
-  }).then(id => {
-    res.locals.operatorId = id
-    return next()
-  }).catch(e => {
-    logger.error('Error while computing operator id\n' + e)
-    next(e)
-  })
+  return getOperatorId()
+    .then(({ id }) => {
+      res.locals.operatorId = id
+      return next()
+    })
+    .catch(e => {
+      console.error('Error while computing operator id\n' + e)
+      next(e)
+    })
 }
 
 module.exports = findOperatorId