add ca download route

lib/pair.js

@@ -1,12 +1,17 @@
 const db = require('./db')
 
-function pair (token, deviceId) {
+function pullToken (token) {
   const sql = `delete from pairing_tokens
     where token=$1
     returning created < now() - interval '1 hour' as expired`
   return db.one(sql, [token])
-  .then(r => {
-    if (r.expired) return false
+  .then(r => r.expired)
+}
+
+function pair (token, deviceId) {
+  pullToken(token)
+  .then(valid => {
+    if (!valid) return false
 
     const pairSql = 'insert into paired_devices (device_id) values ($1)'
     return db.none(pairSql, [deviceId])
@@ -14,6 +19,10 @@ function pair (token, deviceId) {
   })
 }
 
+function authorizeCaDownload (caToken) {
+  return pullToken(caToken)
+}
+
 function isPaired (deviceId) {
   const sql = 'select device_id from paired_devices where device_id=$1'
 
@@ -21,4 +30,4 @@ function isPaired (deviceId) {
   .then(() => true)
 }
 
-module.exports = {pair, isPaired}
+module.exports = {pair, authorizeCaDownload, isPaired}