Debug cache

Author: michielbdejong

lib/acl-checker.js

@@ -3,6 +3,7 @@
 
 const rdf = require('rdflib')
 const debug = require('./debug').ACL
+const debugCache = require('./debug').cache
 const HTTPError = require('./http-error')
 const aclCheck = require('@solid/acl-check')
 const { URL } = require('url')
@@ -216,13 +217,20 @@ function fetchLocalOrRemote (mapper, serverUri) {
     return { body, contentType }
   }
   return async function fetch (url, graph = rdf.graph()) {
-    if (!temporaryCache[url] || temporaryCache[url].timestamp < new Date().getTime() - EXPIRY_MS) {
-      debug(temporaryCache[url] ? `Repopulating cache, content is ${new Date().getTime() - temporaryCache[url].timestamp} ms old` : 'Populating cache', url)
+    if (!temporaryCache[url]) {
+      debugCache('Populating cache', url)
       temporaryCache[url] = {
-        timestamp: new Date().getTime(),
+        timer: setTimeout(() => {
+          debugCache('Expunging from cache', url)
+          delete temporaryCache[url]
+          if (Object.keys(temporaryCache).length === 0) {
+            debugCache('Cache is empty again')
+          }
+        }, EXPIRY_MS),
         promise: doFetch(url)
       }
     }
+    debugCache('Cache hit', url)
     const { body, contentType } = await temporaryCache[url].promise
     // Parse the file as Turtle
     rdf.parse(body, graph, url, contentType)

lib/debug.js

@@ -3,6 +3,7 @@ const debug = require('debug')
 exports.handlers = debug('solid:handlers')
 exports.errors = debug('solid:errors')
 exports.ACL = debug('solid:ACL')
+exports.cache = debug('solid:cache')
 exports.parse = debug('solid:parse')
 exports.metadata = debug('solid:metadata')
 exports.authentication = debug('solid:authentication')