1 files changed, 231 insertions, 0 deletions
diff --git a/trunk/etherpad/src/etherpad/statistics/exceptions.js b/trunk/etherpad/src/etherpad/statistics/exceptions.js
new file mode 100644
index 0000000..723085d
--- /dev/null
+++ b/trunk/etherpad/src/etherpad/statistics/exceptions.js
@@ -0,0 +1,231 @@
+/**
+ * Copyright 2009 Google Inc.
+ * 
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ * 
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS-IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+import("fastJSON");
+import("etherpad.log");
+import("cache_utils.syncedWithCache");
+import("funhtml.*");
+import("jsutils.{eachProperty,keys}");
+
+function _dayKey(date) {
+  return [date.getFullYear(), date.getMonth()+1, date.getDate()].join(',');
+}
+
+function _dateAddDays(date, numDays) {
+  return new Date((+date) + numDays*1000*60*60*24);
+}
+
+function _loadDay(date) {
+  var fileName = log.frontendLogFileName('exception', date);
+  if (! fileName) {
+    return [];
+  }
+  var reader = new java.io.BufferedReader(new java.io.FileReader(fileName));
+  var line = null;
+  var array = [];
+  while ((line = reader.readLine()) !== null) {
+    array.push(fastJSON.parse(line));
+  }
+  return array;
+}
+
+function _accessLatestLogs(func) {
+  syncedWithCache("etherpad.statistics.exceptions", function(exc) {
+    if (! exc.byDay) {
+      exc.byDay = {};
+    }
+    // always reload today from disk
+    var now = new Date();
+    var today = now;
+    var todayKey = _dayKey(today);
+    exc.byDay[todayKey] = _loadDay(today);
+    var activeKeys = {};
+    activeKeys[todayKey] = true;
+    // load any of 7 previous days that aren't loaded or
+    // were not loaded as a historical day
+    for(var i=1;i<=7;i++) {
+      var pastDay = _dateAddDays(today, -i);
+      var pastDayKey = _dayKey(pastDay);
+      activeKeys[pastDayKey] = true;
+      if ((! exc.byDay[pastDayKey]) || (! exc.byDay[pastDayKey].sealed)) {
+        exc.byDay[pastDayKey] = _loadDay(pastDay);
+        exc.byDay[pastDayKey].sealed = true; // in the past, won't change
+      }
+    }
+    // clear old days
+    for(var k in exc.byDay) {
+      if (! (k in activeKeys)) {
+        delete exc.byDay[k];
+      }
+    }
+
+    var logs = {
+      getDay: function(daysAgo) {
+        return exc.byDay[_dayKey(_dateAddDays(today, -daysAgo))];
+      },
+      eachLineInLastNDays: function(n, func) {
+        var oldest = _dateAddDays(now, -n);
+        var oldestNum = +oldest;
+        for(var i=n;i>=0;i--) {
+          var lines = logs.getDay(i);
+          lines.forEach(function(line) {
+            if (line.date > oldestNum) {
+              func(line);
+            }
+          });
+        }
+      }
+    };
+
+    func(logs);
+  });
+}
+
+function _exceptionHash(line) {
+  // skip the first line of jsTrace, take hashCode of rest
+  var trace = line.jsTrace;
+  var stack = trace.substring(trace.indexOf('\n') + 1);
+  return new java.lang.String(stack).hashCode();
+}
+
+// Used to take a series of strings and produce an array of
+// [common prefix, example middle, common suffix], or
+// [string] if the strings are the same.  Takes oldInfo
+// and returns newInfo; each is either null or an array
+// of length 1 or 3.
+function _accumCommonPrefixSuffix(oldInfo, newString) {
+  function _commonPrefixLength(a, b) {
+    var x = 0;
+    while (x < a.length && x < b.length && a.charAt(x) == b.charAt(x)) {
+      x++;
+    }
+    return x;
+  }
+
+  function _commonSuffixLength(a, b) {
+    var x = 0;
+    while (x < a.length && x < b.length &&
+           a.charAt(a.length-1-x) == b.charAt(b.length-1-x)) {
+      x++;
+    }
+    return x;
+  }
+
+  if (! oldInfo) {
+    return [newString];
+  }
+  else if (oldInfo.length == 1) {
+    var oldString = oldInfo[0];
+    if (oldString == newString) {
+      return oldInfo;
+    }
+    var newInfo = [];
+    var a = _commonPrefixLength(oldString, newString);
+    newInfo[0] = newString.substring(0, a);
+    oldString = oldString.substring(a);
+    newString = newString.substring(a);
+    var b = _commonSuffixLength(oldString, newString);
+    newInfo[2] = newString.slice(-b);
+    oldString = oldString.slice(0, -b);
+    newString = newString.slice(0, -b);
+    newInfo[1] = newString;
+    return newInfo;
+  }
+  else {
+    // oldInfo.length == 3
+    var a = _commonPrefixLength(oldInfo[0], newString);
+    var b = _commonSuffixLength(oldInfo[2], newString);
+    return [newString.slice(0, a), newString.slice(a, -b),
+            newString.slice(-b)];
+  }
+}
+
+function render() {
+
+  _accessLatestLogs(function(logs) {
+    var weekCounts = {};
+    var totalWeekCount = 0;
+
+    // count exceptions of each kind in last week
+    logs.eachLineInLastNDays(7, function(line) {
+      var hash = _exceptionHash(line);
+      weekCounts[hash] = (weekCounts[hash] || 0) + 1;
+      totalWeekCount++;
+    });
+
+    var dayData = {};
+    var totalDayCount = 0;
+
+    // accumulate data about each exception in last 24 hours
+    logs.eachLineInLastNDays(1, function(line) {
+      var hash = _exceptionHash(line);
+      var oldData = dayData[hash];
+      var data = (oldData || {});
+      if (! oldData) {
+        data.hash = hash;
+        data.trace = line.jsTrace.substring(line.jsTrace.indexOf('\n')+1);
+        data.trackers = {};
+      }
+      var msg = line.jsTrace.substring(0, line.jsTrace.indexOf('\n'));
+      data.message = _accumCommonPrefixSuffix(data.message, msg);
+      data.count = (data.count || 0)+1;
+      data.trackers[line.tracker] = true;
+      totalDayCount++;
+      dayData[hash] = data;
+    });
+
+    // put day datas in an array and sort
+    var dayDatas = [];
+    eachProperty(dayData, function(k,v) {
+      dayDatas.push(v);
+    });
+    dayDatas.sort(function(a, b) {
+      return b.count - a.count;
+    });
+
+    // process
+    dayDatas.forEach(function(data) {
+      data.weekCount = (weekCounts[data.hash] || 0);
+      data.numTrackers = keys(data.trackers).length;
+    });
+
+    // gen HTML
+    function num(n) { return SPAN({className:'num'}, n); }
+
+    response.write(STYLE(html(".trace { height: 300px; overflow: auto; background: #eee; margin-left: 1em; font-family: monospace; border: 1px solid #833; padding: 4px; }\n"+
+                              ".exc { margin: 1em 0; }\n"+
+                              ".num { font-size: 150%; }")));
+
+    response.write(P("Total exceptions in past day: ", num(totalDayCount),
+                     ", past week: ", totalWeekCount));
+
+    response.write(P(SMALL(EM("Data on this page is live."))));
+
+    response.write(H2("Exceptions grouped by stack trace:"));
+
+    dayDatas.forEach(function(data) {
+      response.write(DIV({className:'exc'},
+                         'Past day: ',num(data.count),', Past week: ',
+                         data.weekCount,', Different tracker cookies today: ',
+                         data.numTrackers,
+                         '\n',data.message[0],
+                         (data.message[1] && I(data.message[1])) || '',
+                         (data.message[2] || ''),'\n',
+                         DIV({className:'trace'}, data.trace)));
+    });
+  });
+}