[tor-commits] [onionoo/master] Add Cache-Control header.

[karsten at torproject.org]

commit cbc03ebf6e0a3ad772440f62357ea3baa7c165e5
Author: Karsten Loesing <karsten.loesing at gmx.net>
Date:   Wed Aug 13 15:54:16 2014 +0200

    Add Cache-Control header.
    
    Set max-age to a value between 5 and 40 minutes, depending on how old the
    node index is.
---
 .../org/torproject/onionoo/server/ResourceServlet.java   |   14 +++++++++++---
 .../java/org/torproject/onionoo/util/DateTimeHelper.java |    1 +
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/src/main/java/org/torproject/onionoo/server/ResourceServlet.java b/src/main/java/org/torproject/onionoo/server/ResourceServlet.java
index 481462e..ee71218 100644
--- a/src/main/java/org/torproject/onionoo/server/ResourceServlet.java
+++ b/src/main/java/org/torproject/onionoo/server/ResourceServlet.java
@@ -61,12 +61,18 @@ public class ResourceServlet extends HttpServlet {
       return;
     }
 
-    if (ApplicationFactory.getNodeIndexer().getLastIndexed(
-        DateTimeHelper.TEN_SECONDS) + DateTimeHelper.SIX_HOURS
-        < ApplicationFactory.getTime().currentTimeMillis()) {
+    long nowMillis = ApplicationFactory.getTime().currentTimeMillis();
+    long indexWrittenMillis =
+        ApplicationFactory.getNodeIndexer().getLastIndexed(
+        DateTimeHelper.TEN_SECONDS);
+    long indexAgeMillis = nowMillis - indexWrittenMillis;
+    if (indexAgeMillis > DateTimeHelper.SIX_HOURS) {
       response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
       return;
     }
+    long cacheMaxAgeMillis = Math.max(DateTimeHelper.FIVE_MINUTES,
+        ((DateTimeHelper.FOURTY_FIVE_MINUTES - indexAgeMillis)
+        / DateTimeHelper.FIVE_MINUTES) * DateTimeHelper.FIVE_MINUTES);
 
     NodeIndex nodeIndex = ApplicationFactory.getNodeIndexer().
         getLatestNodeIndex(DateTimeHelper.TEN_SECONDS);
@@ -304,6 +310,8 @@ public class ResourceServlet extends HttpServlet {
     response.setHeader("Access-Control-Allow-Origin", "*");
     response.setContentType("application/json");
     response.setCharacterEncoding("utf-8");
+    response.setHeader("Cache-Control", "public, max-age="
+        + (cacheMaxAgeMillis / DateTimeHelper.ONE_SECOND));
     PrintWriter pw = response.getWriter();
     rb.buildResponse(pw);
     int relayDocumentsWritten = rh.getOrderedRelays().size();
diff --git a/src/main/java/org/torproject/onionoo/util/DateTimeHelper.java b/src/main/java/org/torproject/onionoo/util/DateTimeHelper.java
index 1fcf6e1..b350b9a 100644
--- a/src/main/java/org/torproject/onionoo/util/DateTimeHelper.java
+++ b/src/main/java/org/torproject/onionoo/util/DateTimeHelper.java
@@ -19,6 +19,7 @@ public class DateTimeHelper {
       ONE_MINUTE = 60L * ONE_SECOND,
       FIVE_MINUTES = 5L * ONE_MINUTE,
       FIFTEEN_MINUTES = 15L * ONE_MINUTE,
+      FOURTY_FIVE_MINUTES = 45L * ONE_MINUTE,
       ONE_HOUR = 60L * ONE_MINUTE,
       FOUR_HOURS = 4L * ONE_HOUR,
       SIX_HOURS = 6L * ONE_HOUR,