[tor-commits] [metrics-web/master] Tell users when we don't have enough data to answer their request.

[karsten at torproject.org]

commit 7314596e198da7581eed449c80d688195b1ed5df
Author: Karsten Loesing <karsten.loesing at gmx.net>
Date:   Fri Jan 13 08:36:18 2012 +0100

    Tell users when we don't have enough data to answer their request.
    
    Fixes #4895.
---
 .../torproject/ernie/web/RelaySearchServlet.java   |   35 ++++++++++++++++++++
 web/WEB-INF/relay-search.jsp                       |    3 ++
 2 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/src/org/torproject/ernie/web/RelaySearchServlet.java b/src/org/torproject/ernie/web/RelaySearchServlet.java
index 512e25f..fe7e62b 100644
--- a/src/org/torproject/ernie/web/RelaySearchServlet.java
+++ b/src/org/torproject/ernie/web/RelaySearchServlet.java
@@ -52,6 +52,8 @@ public class RelaySearchServlet extends HttpServlet {
   private SimpleDateFormat dateTimeFormat =
       new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
 
+  private long minValidAfterMillis;
+
   private DataSource ds;
 
   private Logger logger;
@@ -74,6 +76,27 @@ public class RelaySearchServlet extends HttpServlet {
     } catch (NamingException e) {
       this.logger.log(Level.WARNING, "Could not look up data source", e);
     }
+
+    /* Look up first consensus in the database. */
+    try {
+      long requestedConnection = System.currentTimeMillis();
+      Connection conn = this.ds.getConnection();
+      String query = "SELECT MIN(validafter) AS first FROM consensus";
+      Statement statement = conn.createStatement();
+      ResultSet rs = statement.executeQuery(query);
+      if (rs.next()) {
+        this.minValidAfterMillis = rs.getTimestamp(1).getTime();
+      }
+      rs.close();
+      statement.close();
+      conn.close();
+      this.logger.info("Returned a database connection to the pool "
+          + "after " + (System.currentTimeMillis()
+          - requestedConnection) + " millis.");
+    } catch (SQLException e) {
+      this.logger.log(Level.WARNING, "Could not look up first consensus "
+          + "valid-after time in the database.", e);
+    }
   }
 
   public void doGet(HttpServletRequest request,
@@ -304,6 +327,12 @@ public class RelaySearchServlet extends HttpServlet {
       boolean addOr = false;
       timeIntervalBuilder.append("AND (");
       for (long searchTimestamp : searchDayTimestamps) {
+        if (searchTimestamp < this.minValidAfterMillis) {
+          request.setAttribute("outsideInterval", "Returned search "
+              + "results may be incomplete, as our data only dates back "
+              + "to " + dateTimeFormat.format(this.minValidAfterMillis)
+              + ".  Older archives are not available.");
+        }
         timeIntervalBuilder.append((addOr ? "OR " : "")
             + "(validafter >= '"
             + dateTimeFormat.format(searchTimestamp) + "' AND "
@@ -312,6 +341,12 @@ public class RelaySearchServlet extends HttpServlet {
         addOr = true;
       }
       for (long searchTimestamp : searchMonthTimestamps) {
+        if (searchTimestamp < this.minValidAfterMillis) {
+          request.setAttribute("outsideInterval", "Returned search "
+              + "results may be incomplete, as our data only dates back "
+              + "to " + dateTimeFormat.format(this.minValidAfterMillis)
+              + ".  Older archives are not available.");
+        }
         Calendar firstOfNextMonth = Calendar.getInstance(
             TimeZone.getTimeZone("UTC"));
         firstOfNextMonth.setTimeInMillis(searchTimestamp);
diff --git a/web/WEB-INF/relay-search.jsp b/web/WEB-INF/relay-search.jsp
index 260b7dc..b90938a 100644
--- a/web/WEB-INF/relay-search.jsp
+++ b/web/WEB-INF/relay-search.jsp
@@ -39,6 +39,9 @@
         (e.g., "80.190"). You can also provide at most three months or
         days in ISO 8601 format (e.g., "2010-09" or "2010-09-17").</p>
       </c:if>
+      <c:if test="${not empty outsideInterval}">
+        <p>${outsideInterval}</p>
+      </c:if>
       <c:if test="${not empty searchNotice}">
         <p>${searchNotice}</p>
       </c:if>