change to cached_responses; actively prune table

lib/postgresql_interface.js

@@ -9,6 +9,8 @@ var R = require('ramda')
 
 var logger = require('./logger')
 
+const CACHED_SESSION_TTL = 60 * 60 * 1000
+
 /*
 function inspect(rec) {
   console.log(require('util').inspect(rec, {depth: null, colors: true}))
@@ -52,6 +54,8 @@ exports.init = function init (_conString) {
   if (!conString) {
     throw new Error('Postgres connection string is required')
   }
+
+  setInterval(pruneCachedResponses, CACHED_SESSION_TTL)
 }
 
 function connect (cb) {
@@ -778,12 +782,12 @@ function insertCachedRequest (session, path, method, body) {
     'body'
   ]
 
-  const sql = getInsertQuery('cached_requests', fields)
+  const sql = getInsertQuery('cached_responses', fields)
   return pquery(sql, [session.fingerprint, session.id, path, method, body])
 }
 
 exports.cachedResponse = function (session, path, method) {
-  const sql = `select body from cached_requests
+  const sql = `select body from cached_responses
   where device_fingerprint=$1
   and session_id=$2
   and path=$3
@@ -800,8 +804,17 @@ exports.cachedResponse = function (session, path, method) {
   })
 }
 
+function pruneCachedResponses () {
+  const sql = `delete from cached_responses
+  where (EXTRACT(EPOCH FROM (now() - created))) * 1000 < $1`
+
+  const values = [CACHED_SESSION_TTL]
+
+  return pquery(sql, values)
+}
+
 exports.cacheResponse = function (session, path, method, body) {
-  const sql = `update cached_requests
+  const sql = `update cached_responses
   set body=$1
   where device_fingerprint=$2
   and session_id=$3

migrations/010-cached-requests.js

@@ -3,13 +3,14 @@
 var db = require('./db')
 
 exports.up = function (next) {
-  db.query('CREATE TABLE IF NOT EXISTS cached_requests ( ' +
+  db.query('CREATE TABLE IF NOT EXISTS cached_responses ( ' +
     'id serial PRIMARY KEY, ' +
     'device_fingerprint text NOT NULL, ' +
     'session_id uuid NOT NULL, ' +
     'path text NOT NULL, ' +
     'method text NOT NULL, ' +
     'body json NOT NULL, ' +
+    'created timestampz NOT NULL DEFAULT now(), ' +
     'UNIQUE (device_fingerprint, session_id, path, method) ' +
     ')', next)
 }

todo.txt

@@ -1,8 +1 @@
 - change satoshis to crypto_atoms in db (ask neal about this)
-
-UTC:
-http://justatheory.com/computers/databases/postgresql/use-timestamptz.html
-
-Upgrade instructions:
-
-AFTER migrating, set timezone in config to 'UTC', then restart server