Remove offset / count from provider interface.

Author: Marcelo Vanzin

core/src/main/scala/org/apache/spark/deploy/history/FsHistoryProvider.scala

@@ -86,11 +86,7 @@ private[history] class FsHistoryProvider(conf: SparkConf) extends ApplicationHis
     logCheckingThread.start()
   }
 
-  override def getListing(offset: Int, count: Int) = {
-    val list = appList
-    val theOffset = if (offset < list.size) offset else 0
-    (list.slice(theOffset, Math.min(theOffset + count, list.size)), theOffset, list.size)
-  }
+  override def getListing() = appList
 
   override def getAppInfo(appId: String): ApplicationHistoryInfo = {
     try {
@@ -137,7 +133,7 @@ private[history] class FsHistoryProvider(conf: SparkConf) extends ApplicationHis
         }
       }
 
-      appList = newApps.sortBy { info => -info.lastUpdated }
+      appList = newApps.sortBy { info => -info.endTime }
     } catch {
       case t: Throwable => logError("Exception in checking for event log updates", t)
     }

core/src/main/scala/org/apache/spark/deploy/history/HistoryPage.scala

@@ -30,19 +30,23 @@ private[spark] class HistoryPage(parent: HistoryServer) extends WebUIPage("") {
   def render(request: HttpServletRequest): Seq[Node] = {
     val requestedPage = Option(request.getParameter("page")).getOrElse("1").toInt
     val requestedFirst = (requestedPage - 1) * pageSize
-    val (apps, actualFirst, totalCount) = parent.getApplicationList(requestedFirst, pageSize)
+
+    val allApps = parent.getApplicationList()
+    val actualFirst = if (requestedFirst < allApps.size) requestedFirst else 0
+    val apps = allApps.slice(actualFirst, Math.min(pageSize, allApps.size))
+
     val actualPage = (actualFirst / pageSize) + 1
-    val last = Math.min(actualFirst + pageSize, totalCount) - 1
-    val pageCount = totalCount / pageSize + (if (totalCount % pageSize > 0) 1 else 0)
+    val last = Math.min(actualFirst + pageSize, allApps.size) - 1
+    val pageCount = allApps.size / pageSize + (if (allApps.size % pageSize > 0) 1 else 0)
 
     val appTable = UIUtils.listingTable(appHeader, appRow, apps)
     val content =
       <div class="row-fluid">
         <div class="span12">
           {
-            if (totalCount > 0) {
+            if (allApps.size > 0) {
               <h4>
-                Showing {actualFirst + 1}-{last + 1} of {totalCount}
+                Showing {actualFirst + 1}-{last + 1} of {allApps.size}
                 <span style="float: right">
                   {if (actualPage > 1) <a href={"/?page=" + (actualPage - 1)}>&lt;</a>}
                   {if (actualPage < pageCount) <a href={"/?page=" + (actualPage + 1)}>&gt;</a>}

core/src/main/scala/org/apache/spark/deploy/history/HistoryServer.scala

@@ -151,16 +151,11 @@ class HistoryServer(
   }
 
   /**
-   * Returns a list of available applications, in descending order according to their last
-   * updated time.
+   * Returns a list of available applications, in descending order according to their end time.
    *
-   * @param offset Starting offset for returned objects.
-   * @param count Max number of objects to return.
-   * @return 3-tuple (requested app list, adjusted offset, count of all available apps)
+   * @return List of all known applications.
    */
-  def getApplicationList(offset: Int, count: Int) = {
-    provider.getListing(offset, count)
-  }
+  def getApplicationList() = provider.getListing()
 
 }
 
@@ -272,16 +267,13 @@ private[spark] abstract class ApplicationHistoryProvider {
 
   /**
    * This method should return a list of applications available for the history server to
-   * show. The listing is assumed to be in descending time order.
+   * show.
    *
-   * An adjusted offset should be returned if the app list has changed and the request
-   * references an invalid start offset. Otherwise, the provided offset should be returned.
+   * The listing is assumed to be in descending end time order.
    *
-   * @param offset Starting offset for returned objects.
-   * @param count Max number of objects to return.
-   * @return 3-tuple (requested app list, adjusted offset, count of all available apps)
+   * @return List of all know applications.
    */
-  def getListing(offset: Int, count: Int): (Seq[ApplicationHistoryInfo], Int, Int)
+  def getListing(): Seq[ApplicationHistoryInfo]
 
   /**
    * This method should return the application information, including a rendered SparkUI.