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Posted to common-commits@hadoop.apache.org by gt...@apache.org on 2016/01/20 10:13:30 UTC

[13/50] [abbrv] hadoop git commit: YARN-3901. Populate flow run data in the flow_run & flow activity tables (Vrushali C via sjlee)

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowActivityTable.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowActivityTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowActivityTable.java
new file mode 100644
index 0000000..af8df99
--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowActivityTable.java
@@ -0,0 +1,107 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.io.IOException;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.client.Admin;
+import org.apache.hadoop.hbase.regionserver.BloomType;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.BaseTable;
+
+/**
+ * The flow activity table has column family info
+ * Stores the daily activity record for flows
+ * Useful as a quick lookup of what flows were
+ * running on a given day
+ *
+ * Example flow activity table record:
+ *
+ * </pre>
+ * |-------------------------------------------|
+ * |  Row key   | Column Family                |
+ * |            | info                         |
+ * |-------------------------------------------|
+ * | clusterId! | r!runid1:version1            |
+ * | inv Top of |                              |
+ * | Day!       | r!runid2:version7            |
+ * | userName!  |                              |
+ * | flowId     |                              |
+ * |-------------------------------------------|
+ * </pre>
+ */
+public class FlowActivityTable extends BaseTable<FlowActivityTable> {
+  /** flow activity table prefix */
+  private static final String PREFIX =
+      YarnConfiguration.TIMELINE_SERVICE_PREFIX + ".flowactivity";
+
+  /** config param name that specifies the flowactivity table name */
+  public static final String TABLE_NAME_CONF_NAME = PREFIX + ".table.name";
+
+  /** default value for flowactivity table name */
+  public static final String DEFAULT_TABLE_NAME = "timelineservice.flowactivity";
+
+  private static final Log LOG = LogFactory.getLog(FlowActivityTable.class);
+
+  /** default max number of versions */
+  public static final int DEFAULT_METRICS_MAX_VERSIONS = Integer.MAX_VALUE;
+
+  public FlowActivityTable() {
+    super(TABLE_NAME_CONF_NAME, DEFAULT_TABLE_NAME);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.BaseTable#createTable
+   * (org.apache.hadoop.hbase.client.Admin,
+   * org.apache.hadoop.conf.Configuration)
+   */
+  public void createTable(Admin admin, Configuration hbaseConf)
+      throws IOException {
+
+    TableName table = getTableName(hbaseConf);
+    if (admin.tableExists(table)) {
+      // do not disable / delete existing table
+      // similar to the approach taken by map-reduce jobs when
+      // output directory exists
+      throw new IOException("Table " + table.getNameAsString()
+          + " already exists.");
+    }
+
+    HTableDescriptor FlowActivityTableDescp = new HTableDescriptor(table);
+    HColumnDescriptor infoCF =
+        new HColumnDescriptor(FlowActivityColumnFamily.INFO.getBytes());
+    infoCF.setBloomFilterType(BloomType.ROWCOL);
+    FlowActivityTableDescp.addFamily(infoCF);
+    infoCF.setMinVersions(1);
+    infoCF.setMaxVersions(DEFAULT_METRICS_MAX_VERSIONS);
+
+    // TODO: figure the split policy before running in production
+    admin.createTable(FlowActivityTableDescp);
+    LOG.info("Status of table creation for " + table.getNameAsString() + "="
+        + admin.tableExists(table));
+  }
+}
\ No newline at end of file

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumn.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumn.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumn.java
new file mode 100644
index 0000000..ad30add
--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumn.java
@@ -0,0 +1,161 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.io.IOException;
+
+import org.apache.hadoop.hbase.client.Result;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.Column;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnFamily;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnHelper;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TypedBufferedMutator;
+
+/**
+ * Identifies fully qualified columns for the {@link FlowRunTable}.
+ */
+public enum FlowRunColumn implements Column<FlowRunTable> {
+
+  /**
+   * When the flow was started. This is the minimum of currently known
+   * application start times.
+   */
+  MIN_START_TIME(FlowRunColumnFamily.INFO, "min_start_time",
+      AggregationOperation.MIN),
+
+  /**
+   * When the flow ended. This is the maximum of currently known application end
+   * times.
+   */
+  MAX_END_TIME(FlowRunColumnFamily.INFO, "max_end_time",
+      AggregationOperation.MAX),
+
+  /**
+   * The version of the flow that this flow belongs to.
+   */
+  FLOW_VERSION(FlowRunColumnFamily.INFO, "flow_version", null);
+
+  private final ColumnHelper<FlowRunTable> column;
+  private final ColumnFamily<FlowRunTable> columnFamily;
+  private final String columnQualifier;
+  private final byte[] columnQualifierBytes;
+  private final AggregationOperation aggOp;
+
+  private FlowRunColumn(ColumnFamily<FlowRunTable> columnFamily,
+      String columnQualifier, AggregationOperation aggOp) {
+    this.columnFamily = columnFamily;
+    this.columnQualifier = columnQualifier;
+    this.aggOp = aggOp;
+    // Future-proof by ensuring the right column prefix hygiene.
+    this.columnQualifierBytes = Bytes.toBytes(Separator.SPACE
+        .encode(columnQualifier));
+    this.column = new ColumnHelper<FlowRunTable>(columnFamily);
+  }
+
+  /**
+   * @return the column name value
+   */
+  private String getColumnQualifier() {
+    return columnQualifier;
+  }
+
+  public byte[] getColumnQualifierBytes() {
+    return columnQualifierBytes.clone();
+  }
+
+  public AggregationOperation getAggregationOperation() {
+    return aggOp;
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.Column#store
+   * (byte[], org.apache.hadoop.yarn.server.timelineservice.storage.common.
+   * TypedBufferedMutator, java.lang.Long, java.lang.Object,
+   * org.apache.hadoop.yarn.server.timelineservice.storage.flow.Attribute[])
+   */
+  public void store(byte[] rowKey,
+      TypedBufferedMutator<FlowRunTable> tableMutator, Long timestamp,
+      Object inputValue, Attribute... attributes) throws IOException {
+
+    Attribute[] combinedAttributes = TimelineWriterUtils.combineAttributes(
+        attributes, aggOp);
+    column.store(rowKey, tableMutator, columnQualifierBytes, timestamp,
+        inputValue, combinedAttributes);
+  }
+
+  public Object readResult(Result result) throws IOException {
+    return column.readResult(result, columnQualifierBytes);
+  }
+
+  /**
+   * Retrieve an {@link FlowRunColumn} given a name, or null if there is no
+   * match. The following holds true: {@code columnFor(x) == columnFor(y)} if
+   * and only if {@code x.equals(y)} or {@code (x == y == null)}
+   *
+   * @param columnQualifier
+   *          Name of the column to retrieve
+   * @return the corresponding {@link FlowRunColumn} or null
+   */
+  public static final FlowRunColumn columnFor(String columnQualifier) {
+
+    // Match column based on value, assume column family matches.
+    for (FlowRunColumn ec : FlowRunColumn.values()) {
+      // Find a match based only on name.
+      if (ec.getColumnQualifier().equals(columnQualifier)) {
+        return ec;
+      }
+    }
+
+    // Default to null
+    return null;
+  }
+
+  /**
+   * Retrieve an {@link FlowRunColumn} given a name, or null if there is no
+   * match. The following holds true: {@code columnFor(a,x) == columnFor(b,y)}
+   * if and only if {@code a.equals(b) & x.equals(y)} or
+   * {@code (x == y == null)}
+   *
+   * @param columnFamily
+   *          The columnFamily for which to retrieve the column.
+   * @param name
+   *          Name of the column to retrieve
+   * @return the corresponding {@link FlowRunColumn} or null if both arguments
+   *         don't match.
+   */
+  public static final FlowRunColumn columnFor(FlowRunColumnFamily columnFamily,
+      String name) {
+
+    for (FlowRunColumn ec : FlowRunColumn.values()) {
+      // Find a match based column family and on name.
+      if (ec.columnFamily.equals(columnFamily)
+          && ec.getColumnQualifier().equals(name)) {
+        return ec;
+      }
+    }
+
+    // Default to null
+    return null;
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnFamily.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnFamily.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnFamily.java
new file mode 100644
index 0000000..8faf5f8
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+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnFamily.java
@@ -0,0 +1,54 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnFamily;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
+
+/**
+ * Represents the flow run table column families.
+ */
+public enum FlowRunColumnFamily implements ColumnFamily<FlowRunTable> {
+
+  /**
+   * Info column family houses known columns, specifically ones included in
+   * columnfamily filters.
+   */
+  INFO("i");
+
+  /**
+   * Byte representation of this column family.
+   */
+  private final byte[] bytes;
+
+  /**
+   * @param value
+   *          create a column family with this name. Must be lower case and
+   *          without spaces.
+   */
+  private FlowRunColumnFamily(String value) {
+    // column families should be lower case and not contain any spaces.
+    this.bytes = Bytes.toBytes(Separator.SPACE.encode(value));
+  }
+
+  public byte[] getBytes() {
+    return Bytes.copy(bytes);
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnPrefix.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnPrefix.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnPrefix.java
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+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunColumnPrefix.java
@@ -0,0 +1,239 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.io.IOException;
+import java.util.Map;
+import java.util.NavigableMap;
+
+import org.apache.hadoop.hbase.client.Result;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnFamily;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnHelper;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TypedBufferedMutator;
+
+/**
+ * Identifies partially qualified columns for the {@link FlowRunTable}.
+ */
+public enum FlowRunColumnPrefix implements ColumnPrefix<FlowRunTable> {
+
+  /**
+   * To store flow run info values.
+   */
+  METRIC(FlowRunColumnFamily.INFO, "m", AggregationOperation.SUM);
+
+  private final ColumnHelper<FlowRunTable> column;
+  private final ColumnFamily<FlowRunTable> columnFamily;
+
+  /**
+   * Can be null for those cases where the provided column qualifier is the
+   * entire column name.
+   */
+  private final String columnPrefix;
+  private final byte[] columnPrefixBytes;
+
+  private final AggregationOperation aggOp;
+
+  /**
+   * Private constructor, meant to be used by the enum definition.
+   *
+   * @param columnFamily
+   *          that this column is stored in.
+   * @param columnPrefix
+   *          for this column.
+   */
+  private FlowRunColumnPrefix(ColumnFamily<FlowRunTable> columnFamily,
+      String columnPrefix, AggregationOperation fra) {
+    column = new ColumnHelper<FlowRunTable>(columnFamily);
+    this.columnFamily = columnFamily;
+    this.columnPrefix = columnPrefix;
+    if (columnPrefix == null) {
+      this.columnPrefixBytes = null;
+    } else {
+      // Future-proof by ensuring the right column prefix hygiene.
+      this.columnPrefixBytes = Bytes.toBytes(Separator.SPACE
+          .encode(columnPrefix));
+    }
+    this.aggOp = fra;
+  }
+
+  /**
+   * @return the column name value
+   */
+  public String getColumnPrefix() {
+    return columnPrefix;
+  }
+
+  public byte[] getColumnPrefixBytes() {
+    return columnPrefixBytes.clone();
+  }
+
+  public AggregationOperation getAttribute() {
+    return aggOp;
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix
+   * #store(byte[],
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.
+   * TypedBufferedMutator, java.lang.String, java.lang.Long, java.lang.Object)
+   */
+  public void store(byte[] rowKey,
+      TypedBufferedMutator<FlowRunTable> tableMutator, String qualifier,
+      Long timestamp, Object inputValue, Attribute... attributes)
+      throws IOException {
+
+    // Null check
+    if (qualifier == null) {
+      throw new IOException("Cannot store column with null qualifier in "
+          + tableMutator.getName().getNameAsString());
+    }
+
+    byte[] columnQualifier = ColumnHelper.getColumnQualifier(
+        this.columnPrefixBytes, qualifier);
+    Attribute[] combinedAttributes = TimelineWriterUtils.combineAttributes(
+        attributes, this.aggOp);
+    column.store(rowKey, tableMutator, columnQualifier, timestamp, inputValue,
+        combinedAttributes);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix
+   * #store(byte[],
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.
+   * TypedBufferedMutator, java.lang.String, java.lang.Long, java.lang.Object)
+   */
+  public void store(byte[] rowKey,
+      TypedBufferedMutator<FlowRunTable> tableMutator, byte[] qualifier,
+      Long timestamp, Object inputValue, Attribute... attributes)
+      throws IOException {
+
+    // Null check
+    if (qualifier == null) {
+      throw new IOException("Cannot store column with null qualifier in "
+          + tableMutator.getName().getNameAsString());
+    }
+
+    byte[] columnQualifier = ColumnHelper.getColumnQualifier(
+        this.columnPrefixBytes, qualifier);
+    Attribute[] combinedAttributes = TimelineWriterUtils.combineAttributes(
+        attributes, this.aggOp);
+    column.store(rowKey, tableMutator, columnQualifier, timestamp, inputValue,
+        combinedAttributes);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix
+   * #readResult(org.apache.hadoop.hbase.client.Result, java.lang.String)
+   */
+  public Object readResult(Result result, String qualifier) throws IOException {
+    byte[] columnQualifier = ColumnHelper.getColumnQualifier(
+        this.columnPrefixBytes, qualifier);
+    return column.readResult(result, columnQualifier);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix
+   * #readResults(org.apache.hadoop.hbase.client.Result)
+   */
+  public Map<String, Object> readResults(Result result) throws IOException {
+    return column.readResults(result, columnPrefixBytes);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.common.ColumnPrefix
+   * #readResultsWithTimestamps(org.apache.hadoop.hbase.client.Result)
+   */
+  public <T> NavigableMap<String, NavigableMap<Long, T>> readResultsWithTimestamps(
+      Result result) throws IOException {
+    return column.readResultsWithTimestamps(result, columnPrefixBytes);
+  }
+
+  /**
+   * Retrieve an {@link FlowRunColumnPrefix} given a name, or null if there is
+   * no match. The following holds true: {@code columnFor(x) == columnFor(y)} if
+   * and only if {@code x.equals(y)} or {@code (x == y == null)}
+   *
+   * @param columnPrefix
+   *          Name of the column to retrieve
+   * @return the corresponding {@link FlowRunColumnPrefix} or null
+   */
+  public static final FlowRunColumnPrefix columnFor(String columnPrefix) {
+
+    // Match column based on value, assume column family matches.
+    for (FlowRunColumnPrefix frcp : FlowRunColumnPrefix.values()) {
+      // Find a match based only on name.
+      if (frcp.getColumnPrefix().equals(columnPrefix)) {
+        return frcp;
+      }
+    }
+
+    // Default to null
+    return null;
+  }
+
+  /**
+   * Retrieve an {@link FlowRunColumnPrefix} given a name, or null if there is
+   * no match. The following holds true:
+   * {@code columnFor(a,x) == columnFor(b,y)} if and only if
+   * {@code (x == y == null)} or {@code a.equals(b) & x.equals(y)}
+   *
+   * @param columnFamily
+   *          The columnFamily for which to retrieve the column.
+   * @param columnPrefix
+   *          Name of the column to retrieve
+   * @return the corresponding {@link FlowRunColumnPrefix} or null if both
+   *         arguments don't match.
+   */
+  public static final FlowRunColumnPrefix columnFor(
+      FlowRunColumnFamily columnFamily, String columnPrefix) {
+
+    // TODO: needs unit test to confirm and need to update javadoc to explain
+    // null prefix case.
+
+    for (FlowRunColumnPrefix frcp : FlowRunColumnPrefix.values()) {
+      // Find a match based column family and on name.
+      if (frcp.columnFamily.equals(columnFamily)
+          && (((columnPrefix == null) && (frcp.getColumnPrefix() == null)) || (frcp
+              .getColumnPrefix().equals(columnPrefix)))) {
+        return frcp;
+      }
+    }
+
+    // Default to null
+    return null;
+  }
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunCoprocessor.java
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diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunCoprocessor.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunCoprocessor.java
new file mode 100644
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+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunCoprocessor.java
@@ -0,0 +1,210 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.List;
+import java.util.Map;
+import java.util.NavigableMap;
+import java.util.TreeMap;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.CoprocessorEnvironment;
+import org.apache.hadoop.hbase.HConstants;
+import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.Tag;
+import org.apache.hadoop.hbase.client.Durability;
+import org.apache.hadoop.hbase.client.Get;
+import org.apache.hadoop.hbase.client.Put;
+import org.apache.hadoop.hbase.client.Scan;
+import org.apache.hadoop.hbase.coprocessor.BaseRegionObserver;
+import org.apache.hadoop.hbase.coprocessor.ObserverContext;
+import org.apache.hadoop.hbase.coprocessor.RegionCoprocessorEnvironment;
+import org.apache.hadoop.hbase.regionserver.HRegion;
+import org.apache.hadoop.hbase.regionserver.RegionScanner;
+import org.apache.hadoop.hbase.regionserver.wal.WALEdit;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimestampGenerator;
+
+public class FlowRunCoprocessor extends BaseRegionObserver {
+
+  @SuppressWarnings("unused")
+  private static final Log LOG = LogFactory.getLog(FlowRunCoprocessor.class);
+
+  private HRegion region;
+  /**
+   * generate a timestamp that is unique per row in a region this is per region
+   */
+  private final TimestampGenerator timestampGenerator = new TimestampGenerator();
+
+  @Override
+  public void start(CoprocessorEnvironment e) throws IOException {
+    if (e instanceof RegionCoprocessorEnvironment) {
+      RegionCoprocessorEnvironment env = (RegionCoprocessorEnvironment) e;
+      this.region = env.getRegion();
+    }
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * This method adds the tags onto the cells in the Put. It is presumed that
+   * all the cells in one Put have the same set of Tags. The existing cell
+   * timestamp is overwritten for non-metric cells and each such cell gets a new
+   * unique timestamp generated by {@link TimestampGenerator}
+   *
+   * @see
+   * org.apache.hadoop.hbase.coprocessor.BaseRegionObserver#prePut(org.apache
+   * .hadoop.hbase.coprocessor.ObserverContext,
+   * org.apache.hadoop.hbase.client.Put,
+   * org.apache.hadoop.hbase.regionserver.wal.WALEdit,
+   * org.apache.hadoop.hbase.client.Durability)
+   */
+  @Override
+  public void prePut(ObserverContext<RegionCoprocessorEnvironment> e, Put put,
+      WALEdit edit, Durability durability) throws IOException {
+    Map<String, byte[]> attributes = put.getAttributesMap();
+
+    // Assumption is that all the cells in a put are the same operation.
+    List<Tag> tags = new ArrayList<>();
+    if ((attributes != null) && (attributes.size() > 0)) {
+      for (Map.Entry<String, byte[]> attribute : attributes.entrySet()) {
+        Tag t = TimelineWriterUtils.getTagFromAttribute(attribute);
+        tags.add(t);
+      }
+      byte[] tagByteArray = Tag.fromList(tags);
+      NavigableMap<byte[], List<Cell>> newFamilyMap = new TreeMap<>(
+          Bytes.BYTES_COMPARATOR);
+      for (Map.Entry<byte[], List<Cell>> entry : put.getFamilyCellMap()
+          .entrySet()) {
+        List<Cell> newCells = new ArrayList<>(entry.getValue().size());
+        for (Cell cell : entry.getValue()) {
+          // for each cell in the put add the tags
+          // Assumption is that all the cells in
+          // one put are the same operation
+          // also, get a unique cell timestamp for non-metric cells
+          // this way we don't inadvertently overwrite cell versions
+          long cellTimestamp = getCellTimestamp(cell.getTimestamp(), tags);
+          newCells.add(CellUtil.createCell(CellUtil.cloneRow(cell),
+              CellUtil.cloneFamily(cell), CellUtil.cloneQualifier(cell),
+              cellTimestamp, KeyValue.Type.Put, CellUtil.cloneValue(cell),
+              tagByteArray));
+        }
+        newFamilyMap.put(entry.getKey(), newCells);
+      } // for each entry
+      // Update the family map for the Put
+      put.setFamilyCellMap(newFamilyMap);
+    }
+  }
+
+  /**
+   * Determines if the current cell's timestamp is to be used or a new unique
+   * cell timestamp is to be used. The reason this is done is to inadvertently
+   * overwrite cells when writes come in very fast. But for metric cells, the
+   * cell timestamp signifies the metric timestamp. Hence we don't want to
+   * overwrite it.
+   *
+   * @param timestamp
+   * @param tags
+   * @return cell timestamp
+   */
+  private long getCellTimestamp(long timestamp, List<Tag> tags) {
+    // if ts not set (hbase sets to HConstants.LATEST_TIMESTAMP by default)
+    // then use the generator
+    if (timestamp == HConstants.LATEST_TIMESTAMP) {
+      return timestampGenerator.getUniqueTimestamp();
+    } else {
+      return timestamp;
+    }
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * Creates a {@link FlowScanner} Scan so that it can correctly process the
+   * contents of {@link FlowRunTable}.
+   *
+   * @see
+   * org.apache.hadoop.hbase.coprocessor.BaseRegionObserver#preGetOp(org.apache
+   * .hadoop.hbase.coprocessor.ObserverContext,
+   * org.apache.hadoop.hbase.client.Get, java.util.List)
+   */
+  @Override
+  public void preGetOp(ObserverContext<RegionCoprocessorEnvironment> e,
+      Get get, List<Cell> results) throws IOException {
+    Scan scan = new Scan(get);
+    scan.setMaxVersions();
+    RegionScanner scanner = null;
+    try {
+      scanner = new FlowScanner(region, scan.getBatch(),
+          region.getScanner(scan));
+      scanner.next(results);
+      e.bypass();
+    } finally {
+      if (scanner != null) {
+        scanner.close();
+      }
+    }
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * Ensures that max versions are set for the Scan so that metrics can be
+   * correctly aggregated and min/max can be correctly determined.
+   *
+   * @see
+   * org.apache.hadoop.hbase.coprocessor.BaseRegionObserver#preScannerOpen(org
+   * .apache.hadoop.hbase.coprocessor.ObserverContext,
+   * org.apache.hadoop.hbase.client.Scan,
+   * org.apache.hadoop.hbase.regionserver.RegionScanner)
+   */
+  @Override
+  public RegionScanner preScannerOpen(
+      ObserverContext<RegionCoprocessorEnvironment> e, Scan scan,
+      RegionScanner s) throws IOException {
+    // set max versions for scan to see all
+    // versions to aggregate for metrics
+    scan.setMaxVersions();
+    return s;
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * Creates a {@link FlowScanner} Scan so that it can correctly process the
+   * contents of {@link FlowRunTable}.
+   *
+   * @see
+   * org.apache.hadoop.hbase.coprocessor.BaseRegionObserver#postScannerOpen(
+   * org.apache.hadoop.hbase.coprocessor.ObserverContext,
+   * org.apache.hadoop.hbase.client.Scan,
+   * org.apache.hadoop.hbase.regionserver.RegionScanner)
+   */
+  @Override
+  public RegionScanner postScannerOpen(
+      ObserverContext<RegionCoprocessorEnvironment> e, Scan scan,
+      RegionScanner scanner) throws IOException {
+    return new FlowScanner(region, scan.getBatch(), scanner);
+  }
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunRowKey.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunRowKey.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunRowKey.java
new file mode 100644
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--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunRowKey.java
@@ -0,0 +1,50 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
+
+/**
+ * Represents a rowkey for the flow run table.
+ */
+public class FlowRunRowKey {
+  // TODO: more methods are needed for this class like parse row key
+
+  /**
+   * Constructs a row key for the entity table as follows: {
+   * clusterId!userI!flowId!Inverted Flow Run Id}
+   *
+   * @param clusterId
+   * @param userId
+   * @param flowId
+   * @param flowRunId
+   * @return byte array with the row key
+   */
+  public static byte[] getRowKey(String clusterId, String userId,
+      String flowId, Long flowRunId) {
+    byte[] first = Bytes.toBytes(Separator.QUALIFIERS.joinEncoded(clusterId,
+        userId, flowId));
+    // Note that flowRunId is a long, so we can't encode them all at the same
+    // time.
+    byte[] second = Bytes.toBytes(TimelineWriterUtils.invert(flowRunId));
+    return Separator.QUALIFIERS.join(first, second);
+  }
+
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunTable.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunTable.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunTable.java
new file mode 100644
index 0000000..b1b93c1
--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowRunTable.java
@@ -0,0 +1,141 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.io.IOException;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.HColumnDescriptor;
+import org.apache.hadoop.hbase.HTableDescriptor;
+import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.client.Admin;
+import org.apache.hadoop.hbase.regionserver.BloomType;
+import org.apache.hadoop.yarn.conf.YarnConfiguration;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.BaseTable;
+
+/**
+ * The flow run table has column family info
+ * Stores per flow run information
+ * aggregated across applications.
+ *
+ * Metrics are also stored in the info column family.
+ *
+ * Example flow run table record:
+ *
+ * <pre>
+ * flow_run table
+ * |-------------------------------------------|
+ * |  Row key   | Column Family                |
+ * |            | info                         |
+ * |-------------------------------------------|
+ * | clusterId! | flow_version:version7        |
+ * | userName!  |                              |
+ * | flowId!    | running_apps:1               |
+ * | flowRunId  |                              |
+ * |            | min_start_time:1392995080000 |
+ * |            | #0:""                        |
+ * |            |                              |
+ * |            | min_start_time:1392995081012 |
+ * |            | #0:appId2                    |
+ * |            |                              |
+ * |            | min_start_time:1392993083210 |
+ * |            | #0:appId3                    |
+ * |            |                              |
+ * |            |                              |
+ * |            | max_end_time:1392993084018   |
+ * |            | #0:""                        |
+ * |            |                              |
+ * |            |                              |
+ * |            | m!mapInputRecords:127        |
+ * |            | #0:""                        |
+ * |            |                              |
+ * |            | m!mapInputRecords:31         |
+ * |            | #2:appId2                    |
+ * |            |                              |
+ * |            | m!mapInputRecords:37         |
+ * |            | #1:appId3                    |
+ * |            |                              |
+ * |            |                              |
+ * |            | m!mapOutputRecords:181       |
+ * |            | #0:""                        |
+ * |            |                              |
+ * |            | m!mapOutputRecords:37        |
+ * |            | #1:appId3                    |
+ * |            |                              |
+ * |            |                              |
+ * |-------------------------------------------|
+ * </pre>
+ */
+public class FlowRunTable extends BaseTable<FlowRunTable> {
+  /** entity prefix */
+  private static final String PREFIX =
+      YarnConfiguration.TIMELINE_SERVICE_PREFIX + ".flowrun";
+
+  /** config param name that specifies the flowrun table name */
+  public static final String TABLE_NAME_CONF_NAME = PREFIX + ".table.name";
+
+  /** default value for flowrun table name */
+  public static final String DEFAULT_TABLE_NAME = "timelineservice.flowrun";
+
+  private static final Log LOG = LogFactory.getLog(FlowRunTable.class);
+
+  /** default max number of versions */
+  public static final int DEFAULT_METRICS_MAX_VERSIONS = Integer.MAX_VALUE;
+
+  public FlowRunTable() {
+    super(TABLE_NAME_CONF_NAME, DEFAULT_TABLE_NAME);
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see
+   * org.apache.hadoop.yarn.server.timelineservice.storage.BaseTable#createTable
+   * (org.apache.hadoop.hbase.client.Admin,
+   * org.apache.hadoop.conf.Configuration)
+   */
+  public void createTable(Admin admin, Configuration hbaseConf)
+      throws IOException {
+
+    TableName table = getTableName(hbaseConf);
+    if (admin.tableExists(table)) {
+      // do not disable / delete existing table
+      // similar to the approach taken by map-reduce jobs when
+      // output directory exists
+      throw new IOException("Table " + table.getNameAsString()
+          + " already exists.");
+    }
+
+    HTableDescriptor flowRunTableDescp = new HTableDescriptor(table);
+    HColumnDescriptor infoCF =
+        new HColumnDescriptor(FlowRunColumnFamily.INFO.getBytes());
+    infoCF.setBloomFilterType(BloomType.ROWCOL);
+    flowRunTableDescp.addFamily(infoCF);
+    infoCF.setMinVersions(1);
+    infoCF.setMaxVersions(DEFAULT_METRICS_MAX_VERSIONS);
+
+    // TODO: figure the split policy
+    flowRunTableDescp.addCoprocessor(FlowRunCoprocessor.class
+        .getCanonicalName());
+    admin.createTable(flowRunTableDescp);
+    LOG.info("Status of table creation for " + table.getNameAsString() + "="
+        + admin.tableExists(table));
+  }
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowScanner.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowScanner.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowScanner.java
new file mode 100644
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--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/main/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/FlowScanner.java
@@ -0,0 +1,486 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.Cell;
+import org.apache.hadoop.hbase.CellUtil;
+import org.apache.hadoop.hbase.HRegionInfo;
+import org.apache.hadoop.hbase.KeyValue;
+import org.apache.hadoop.hbase.Tag;
+import org.apache.hadoop.hbase.regionserver.HRegion;
+import org.apache.hadoop.hbase.regionserver.InternalScanner;
+import org.apache.hadoop.hbase.regionserver.RegionScanner;
+import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.util.Bytes.ByteArrayComparator;
+import org.apache.hadoop.yarn.server.timeline.GenericObjectMapper;
+import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
+
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+import java.util.SortedSet;
+import java.util.TreeSet;
+
+/**
+ * Invoked via the coprocessor when a Get or a Scan is issued for flow run
+ * table. Looks through the list of cells per row, checks their tags and does
+ * operation on those cells as per the cell tags. Transforms reads of the stored
+ * metrics into calculated sums for each column Also, finds the min and max for
+ * start and end times in a flow run.
+ */
+class FlowScanner implements RegionScanner, Closeable {
+
+  private static final Log LOG = LogFactory.getLog(FlowScanner.class);
+
+  private final HRegion region;
+  private final InternalScanner flowRunScanner;
+  private RegionScanner regionScanner;
+  private final int limit;
+  private boolean hasMore;
+  private byte[] currentRow;
+  private List<Cell> availableCells = new ArrayList<>();
+  private int currentIndex;
+
+  FlowScanner(HRegion region, int limit, InternalScanner internalScanner) {
+    this.region = region;
+    this.limit = limit;
+    this.flowRunScanner = internalScanner;
+    if (internalScanner instanceof RegionScanner) {
+      this.regionScanner = (RegionScanner) internalScanner;
+    }
+    // TODO: note if it's compaction/flush
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see org.apache.hadoop.hbase.regionserver.RegionScanner#getRegionInfo()
+   */
+  @Override
+  public HRegionInfo getRegionInfo() {
+    return region.getRegionInfo();
+  }
+
+  @Override
+  public boolean nextRaw(List<Cell> cells) throws IOException {
+    return nextRaw(cells, limit);
+  }
+
+  @Override
+  public boolean nextRaw(List<Cell> cells, int limit) throws IOException {
+    return nextInternal(cells, limit);
+  }
+
+  @Override
+  public boolean next(List<Cell> cells) throws IOException {
+    return next(cells, limit);
+  }
+
+  @Override
+  public boolean next(List<Cell> cells, int limit) throws IOException {
+    return nextInternal(cells, limit);
+  }
+
+  private String getAggregationCompactionDimension(List<Tag> tags) {
+    String appId = null;
+    for (Tag t : tags) {
+      if (AggregationCompactionDimension.APPLICATION_ID.getTagType() == t
+          .getType()) {
+        appId = Bytes.toString(t.getValue());
+      }
+    }
+    return appId;
+  }
+
+  /**
+   * This method loops through the cells in a given row of the
+   * {@link FlowRunTable}. It looks at the tags of each cell to figure out how
+   * to process the contents. It then calculates the sum or min or max for each
+   * column or returns the cell as is.
+   *
+   * @param cells
+   * @param limit
+   * @return true if next row is available for the scanner, false otherwise
+   * @throws IOException
+   */
+  private boolean nextInternal(List<Cell> cells, int limit) throws IOException {
+    Cell cell = null;
+    startNext();
+    // Loop through all the cells in this row
+    // For min/max/metrics we do need to scan the entire set of cells to get the
+    // right one
+    // But with flush/compaction, the number of cells being scanned will go down
+    // cells are grouped per column qualifier then sorted by cell timestamp
+    // (latest to oldest) per column qualifier
+    // So all cells in one qualifier come one after the other before we see the
+    // next column qualifier
+    ByteArrayComparator comp = new ByteArrayComparator();
+    byte[] currentColumnQualifier = TimelineWriterUtils.EMPTY_BYTES;
+    AggregationOperation currentAggOp = null;
+    SortedSet<Cell> currentColumnCells = new TreeSet<>(KeyValue.COMPARATOR);
+    Set<String> alreadySeenAggDim = new HashSet<>();
+    int addedCnt = 0;
+    while (((cell = peekAtNextCell(limit)) != null)
+        && (limit <= 0 || addedCnt < limit)) {
+      byte[] newColumnQualifier = CellUtil.cloneQualifier(cell);
+      if (comp.compare(currentColumnQualifier, newColumnQualifier) != 0) {
+        addedCnt += emitCells(cells, currentColumnCells, currentAggOp);
+        resetState(currentColumnCells, alreadySeenAggDim);
+        currentColumnQualifier = newColumnQualifier;
+        currentAggOp = getCurrentAggOp(cell);
+      }
+      collectCells(currentColumnCells, currentAggOp, cell, alreadySeenAggDim);
+      nextCell(limit);
+    }
+    if (!currentColumnCells.isEmpty()) {
+      emitCells(cells, currentColumnCells, currentAggOp);
+    }
+    return hasMore();
+  }
+
+  private AggregationOperation getCurrentAggOp(Cell cell) {
+    List<Tag> tags = Tag.asList(cell.getTagsArray(), cell.getTagsOffset(),
+        cell.getTagsLength());
+    // We assume that all the operations for a particular column are the same
+    return TimelineWriterUtils.getAggregationOperationFromTagsList(tags);
+  }
+
+  /**
+   * resets the parameters to an intialized state for next loop iteration
+   *
+   * @param cell
+   * @param currentAggOp
+   * @param currentColumnCells
+   * @param alreadySeenAggDim
+   * @param collectedButNotEmitted
+   */
+  private void resetState(SortedSet<Cell> currentColumnCells,
+      Set<String> alreadySeenAggDim) {
+    currentColumnCells.clear();
+    alreadySeenAggDim.clear();
+  }
+
+  private void collectCells(SortedSet<Cell> currentColumnCells,
+      AggregationOperation currentAggOp, Cell cell,
+      Set<String> alreadySeenAggDim) throws IOException {
+    if (currentAggOp == null) {
+      // not a min/max/metric cell, so just return it as is
+      currentColumnCells.add(cell);
+      nextCell(limit);
+      return;
+    }
+
+    switch (currentAggOp) {
+    case MIN:
+      if (currentColumnCells.size() == 0) {
+        currentColumnCells.add(cell);
+      } else {
+        Cell currentMinCell = currentColumnCells.first();
+        Cell newMinCell = compareCellValues(currentMinCell, cell, currentAggOp);
+        if (!currentMinCell.equals(newMinCell)) {
+          currentColumnCells.remove(currentMinCell);
+          currentColumnCells.add(newMinCell);
+        }
+      }
+      break;
+    case MAX:
+      if (currentColumnCells.size() == 0) {
+        currentColumnCells.add(cell);
+      } else {
+        Cell currentMaxCell = currentColumnCells.first();
+        Cell newMaxCell = compareCellValues(currentMaxCell, cell, currentAggOp);
+        if (!currentMaxCell.equals(newMaxCell)) {
+          currentColumnCells.remove(currentMaxCell);
+          currentColumnCells.add(newMaxCell);
+        }
+      }
+      break;
+    case SUM:
+    case SUM_FINAL:
+      // only if this app has not been seen yet, add to current column cells
+      List<Tag> tags = Tag.asList(cell.getTagsArray(), cell.getTagsOffset(),
+          cell.getTagsLength());
+      String aggDim = getAggregationCompactionDimension(tags);
+      if (alreadySeenAggDim.contains(aggDim)) {
+        // if this agg dimension has already been seen,
+        // since they show up in sorted order
+        // we drop the rest which are older
+        // in other words, this cell is older than previously seen cells
+        // for that agg dim
+      } else {
+        // not seen this agg dim, hence consider this cell in our working set
+        currentColumnCells.add(cell);
+        alreadySeenAggDim.add(aggDim);
+      }
+      break;
+    default:
+      break;
+    } // end of switch case
+  }
+
+  /*
+   * Processes the cells in input param currentColumnCells and populates
+   * List<Cell> cells as the output based on the input AggregationOperation
+   * parameter.
+   */
+  private int emitCells(List<Cell> cells, SortedSet<Cell> currentColumnCells,
+      AggregationOperation currentAggOp) throws IOException {
+    if ((currentColumnCells == null) || (currentColumnCells.size() == 0)) {
+      return 0;
+    }
+    if (currentAggOp == null) {
+      cells.addAll(currentColumnCells);
+      return currentColumnCells.size();
+    }
+
+    switch (currentAggOp) {
+    case MIN:
+    case MAX:
+      cells.addAll(currentColumnCells);
+      return currentColumnCells.size();
+    case SUM:
+    case SUM_FINAL:
+      Cell sumCell = processSummation(currentColumnCells);
+      cells.add(sumCell);
+      return 1;
+    default:
+      cells.addAll(currentColumnCells);
+      return currentColumnCells.size();
+    }
+  }
+
+  /*
+   * Returns a cell whose value is the sum of all cell values in the input set.
+   * The new cell created has the timestamp of the most recent metric cell. The
+   * sum of a metric for a flow run is the summation at the point of the last
+   * metric update in that flow till that time.
+   */
+  private Cell processSummation(SortedSet<Cell> currentColumnCells)
+      throws IOException {
+    Number sum = 0;
+    Number currentValue = 0;
+    long ts = 0L;
+    long mostCurrentTimestamp = 0l;
+    Cell mostRecentCell = null;
+    for (Cell cell : currentColumnCells) {
+      currentValue = (Number) GenericObjectMapper.read(CellUtil
+          .cloneValue(cell));
+      ts = cell.getTimestamp();
+      if (mostCurrentTimestamp < ts) {
+        mostCurrentTimestamp = ts;
+        mostRecentCell = cell;
+      }
+      sum = sum.longValue() + currentValue.longValue();
+    }
+    Cell sumCell = createNewCell(mostRecentCell, sum);
+    return sumCell;
+  }
+
+  /**
+   * Determines which cell is to be returned based on the values in each cell
+   * and the comparison operation MIN or MAX.
+   *
+   * @param previouslyChosenCell
+   * @param currentCell
+   * @param currentAggOp
+   * @return the cell which is the min (or max) cell
+   * @throws IOException
+   */
+  private Cell compareCellValues(Cell previouslyChosenCell, Cell currentCell,
+      AggregationOperation currentAggOp) throws IOException {
+    if (previouslyChosenCell == null) {
+      return currentCell;
+    }
+    try {
+      long previouslyChosenCellValue = ((Number) GenericObjectMapper
+          .read(CellUtil.cloneValue(previouslyChosenCell))).longValue();
+      long currentCellValue = ((Number) GenericObjectMapper.read(CellUtil
+          .cloneValue(currentCell))).longValue();
+      switch (currentAggOp) {
+      case MIN:
+        if (currentCellValue < previouslyChosenCellValue) {
+          // new value is minimum, hence return this cell
+          return currentCell;
+        } else {
+          // previously chosen value is miniumum, hence return previous min cell
+          return previouslyChosenCell;
+        }
+      case MAX:
+        if (currentCellValue > previouslyChosenCellValue) {
+          // new value is max, hence return this cell
+          return currentCell;
+        } else {
+          // previously chosen value is max, hence return previous max cell
+          return previouslyChosenCell;
+        }
+      default:
+        return currentCell;
+      }
+    } catch (IllegalArgumentException iae) {
+      LOG.error("caught iae during conversion to long ", iae);
+      return currentCell;
+    }
+  }
+
+  private Cell createNewCell(Cell origCell, Number number) throws IOException {
+    byte[] newValue = GenericObjectMapper.write(number);
+    return CellUtil.createCell(CellUtil.cloneRow(origCell),
+        CellUtil.cloneFamily(origCell), CellUtil.cloneQualifier(origCell),
+        origCell.getTimestamp(), KeyValue.Type.Put.getCode(), newValue);
+  }
+
+  @Override
+  public void close() throws IOException {
+    flowRunScanner.close();
+  }
+
+  /**
+   * Called to signal the start of the next() call by the scanner.
+   */
+  public void startNext() {
+    currentRow = null;
+  }
+
+  /**
+   * Returns whether or not the underlying scanner has more rows.
+   */
+  public boolean hasMore() {
+    return currentIndex < availableCells.size() ? true : hasMore;
+  }
+
+  /**
+   * Returns the next available cell for the current row and advances the
+   * pointer to the next cell. This method can be called multiple times in a row
+   * to advance through all the available cells.
+   *
+   * @param limit
+   *          the limit of number of cells to return if the next batch must be
+   *          fetched by the wrapped scanner
+   * @return the next available cell or null if no more cells are available for
+   *         the current row
+   * @throws IOException
+   */
+  public Cell nextCell(int limit) throws IOException {
+    Cell cell = peekAtNextCell(limit);
+    if (cell != null) {
+      currentIndex++;
+    }
+    return cell;
+  }
+
+  /**
+   * Returns the next available cell for the current row, without advancing the
+   * pointer. Calling this method multiple times in a row will continue to
+   * return the same cell.
+   *
+   * @param limit
+   *          the limit of number of cells to return if the next batch must be
+   *          fetched by the wrapped scanner
+   * @return the next available cell or null if no more cells are available for
+   *         the current row
+   * @throws IOException
+   */
+  public Cell peekAtNextCell(int limit) throws IOException {
+    if (currentIndex >= availableCells.size()) {
+      // done with current batch
+      availableCells.clear();
+      currentIndex = 0;
+      hasMore = flowRunScanner.next(availableCells, limit);
+    }
+    Cell cell = null;
+    if (currentIndex < availableCells.size()) {
+      cell = availableCells.get(currentIndex);
+      if (currentRow == null) {
+        currentRow = CellUtil.cloneRow(cell);
+      } else if (!CellUtil.matchingRow(cell, currentRow)) {
+        // moved on to the next row
+        // don't use the current cell
+        // also signal no more cells for this row
+        return null;
+      }
+    }
+    return cell;
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see org.apache.hadoop.hbase.regionserver.RegionScanner#getMaxResultSize()
+   */
+  @Override
+  public long getMaxResultSize() {
+    if (regionScanner == null) {
+      throw new IllegalStateException(
+          "RegionScanner.isFilterDone() called when the flow "
+              + "scanner's scanner is not a RegionScanner");
+    }
+    return regionScanner.getMaxResultSize();
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see org.apache.hadoop.hbase.regionserver.RegionScanner#getMvccReadPoint()
+   */
+  @Override
+  public long getMvccReadPoint() {
+    if (regionScanner == null) {
+      throw new IllegalStateException(
+          "RegionScanner.isFilterDone() called when the flow "
+              + "scanner's internal scanner is not a RegionScanner");
+    }
+    return regionScanner.getMvccReadPoint();
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see org.apache.hadoop.hbase.regionserver.RegionScanner#isFilterDone()
+   */
+  @Override
+  public boolean isFilterDone() throws IOException {
+    if (regionScanner == null) {
+      throw new IllegalStateException(
+          "RegionScanner.isFilterDone() called when the flow "
+              + "scanner's internal scanner is not a RegionScanner");
+    }
+    return regionScanner.isFilterDone();
+
+  }
+
+  /*
+   * (non-Javadoc)
+   *
+   * @see org.apache.hadoop.hbase.regionserver.RegionScanner#reseek(byte[])
+   */
+  @Override
+  public boolean reseek(byte[] bytes) throws IOException {
+    if (regionScanner == null) {
+      throw new IllegalStateException(
+          "RegionScanner.reseek() called when the flow "
+              + "scanner's internal scanner is not a RegionScanner");
+    }
+    return regionScanner.reseek(bytes);
+  }
+}

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/TestHBaseTimelineStorage.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/TestHBaseTimelineStorage.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/TestHBaseTimelineStorage.java
index 2875e01..3962341 100644
--- a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/TestHBaseTimelineStorage.java
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/TestHBaseTimelineStorage.java
@@ -53,7 +53,6 @@ import org.apache.hadoop.yarn.server.timelineservice.storage.application.Applica
 import org.apache.hadoop.yarn.server.timelineservice.storage.application.ApplicationColumnPrefix;
 import org.apache.hadoop.yarn.server.timelineservice.storage.application.ApplicationRowKey;
 import org.apache.hadoop.yarn.server.timelineservice.storage.application.ApplicationTable;
-import org.apache.hadoop.yarn.server.timelineservice.storage.apptoflow.AppToFlowTable;
 import org.apache.hadoop.yarn.server.timelineservice.storage.common.Separator;
 import org.apache.hadoop.yarn.server.timelineservice.storage.common.TimelineWriterUtils;
 import org.apache.hadoop.yarn.server.timelineservice.storage.entity.EntityColumn;
@@ -88,20 +87,15 @@ public class TestHBaseTimelineStorage {
   }
 
   private static void createSchema() throws IOException {
-    new EntityTable()
-        .createTable(util.getHBaseAdmin(), util.getConfiguration());
-    new AppToFlowTable()
-        .createTable(util.getHBaseAdmin(), util.getConfiguration());
-    new ApplicationTable()
-        .createTable(util.getHBaseAdmin(), util.getConfiguration());
+    TimelineSchemaCreator.createAllTables(util.getConfiguration(), false);
   }
 
   @Test
   public void testWriteApplicationToHBase() throws Exception {
     TimelineEntities te = new TimelineEntities();
     ApplicationEntity entity = new ApplicationEntity();
-    String id = "hello";
-    entity.setId(id);
+    String appId = "application_1000178881110_2002";
+    entity.setId(appId);
     long cTime = 1425016501000L;
     long mTime = 1425026901000L;
     entity.setCreatedTime(cTime);
@@ -173,12 +167,12 @@ public class TestHBaseTimelineStorage {
       String flow = "some_flow_name";
       String flowVersion = "AB7822C10F1111";
       long runid = 1002345678919L;
-      hbi.write(cluster, user, flow, flowVersion, runid, id, te);
+      hbi.write(cluster, user, flow, flowVersion, runid, appId, te);
       hbi.stop();
 
       // retrieve the row
       byte[] rowKey =
-          ApplicationRowKey.getRowKey(cluster, user, flow, runid, id);
+          ApplicationRowKey.getRowKey(cluster, user, flow, runid, appId);
       Get get = new Get(rowKey);
       get.setMaxVersions(Integer.MAX_VALUE);
       Connection conn = ConnectionFactory.createConnection(c1);
@@ -190,11 +184,11 @@ public class TestHBaseTimelineStorage {
       // check the row key
       byte[] row1 = result.getRow();
       assertTrue(isApplicationRowKeyCorrect(row1, cluster, user, flow, runid,
-          id));
+          appId));
 
       // check info column family
       String id1 = ApplicationColumn.ID.readResult(result).toString();
-      assertEquals(id, id1);
+      assertEquals(appId, id1);
 
       Number val =
           (Number) ApplicationColumn.CREATED_TIME.readResult(result);
@@ -252,17 +246,17 @@ public class TestHBaseTimelineStorage {
       assertEquals(metricValues, metricMap);
 
       // read the timeline entity using the reader this time
-      TimelineEntity e1 = hbr.getEntity(user, cluster, flow, runid, id,
+      TimelineEntity e1 = hbr.getEntity(user, cluster, flow, runid, appId,
           entity.getType(), entity.getId(),
           EnumSet.of(TimelineReader.Field.ALL));
       Set<TimelineEntity> es1 = hbr.getEntities(user, cluster, flow, runid,
-          id, entity.getType(), null, null, null, null, null, null, null,
+          appId, entity.getType(), null, null, null, null, null, null, null,
           null, null, null, null, EnumSet.of(TimelineReader.Field.ALL));
       assertNotNull(e1);
       assertEquals(1, es1.size());
 
       // verify attributes
-      assertEquals(id, e1.getId());
+      assertEquals(appId, e1.getId());
       assertEquals(TimelineEntityType.YARN_APPLICATION.toString(),
           e1.getType());
       assertEquals(cTime, e1.getCreatedTime());
@@ -576,7 +570,7 @@ public class TestHBaseTimelineStorage {
       String flow = "other_flow_name";
       String flowVersion = "1111F01C2287BA";
       long runid = 1009876543218L;
-      String appName = "some app name";
+      String appName = "application_123465899910_1001";
       hbi.write(cluster, user, flow, flowVersion, runid, appName, entities);
       hbi.stop();
 

http://git-wip-us.apache.org/repos/asf/hadoop/blob/a469bfe7/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/TestFlowDataGenerator.java
----------------------------------------------------------------------
diff --git a/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/TestFlowDataGenerator.java b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/TestFlowDataGenerator.java
new file mode 100644
index 0000000..f8331fa
--- /dev/null
+++ b/hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-timelineservice/src/test/java/org/apache/hadoop/yarn/server/timelineservice/storage/flow/TestFlowDataGenerator.java
@@ -0,0 +1,213 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you 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.
+ */
+
+package org.apache.hadoop.yarn.server.timelineservice.storage.flow;
+
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Map;
+import java.util.Set;
+
+import org.apache.hadoop.yarn.api.records.timelineservice.TimelineEntity;
+import org.apache.hadoop.yarn.api.records.timelineservice.TimelineEntityType;
+import org.apache.hadoop.yarn.api.records.timelineservice.TimelineEvent;
+import org.apache.hadoop.yarn.api.records.timelineservice.TimelineMetric;
+import org.apache.hadoop.yarn.api.records.timelineservice.TimelineMetric.Type;
+import org.apache.hadoop.yarn.server.metrics.ApplicationMetricsConstants;
+
+/**
+ * Generates the data/entities for the FlowRun and FlowActivity Tables
+ */
+class TestFlowDataGenerator {
+
+  private final static String metric1 = "MAP_SLOT_MILLIS";
+  private final static String metric2 = "HDFS_BYTES_READ";
+
+
+  static TimelineEntity getEntityMetricsApp1() {
+    TimelineEntity entity = new TimelineEntity();
+    String id = "flowRunMetrics_test";
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setId(id);
+    entity.setType(type);
+    Long cTime = 1425016501000L;
+    entity.setCreatedTime(cTime);
+
+    // add metrics
+    Set<TimelineMetric> metrics = new HashSet<>();
+    TimelineMetric m1 = new TimelineMetric();
+    m1.setId(metric1);
+    Map<Long, Number> metricValues = new HashMap<Long, Number>();
+    long ts = System.currentTimeMillis();
+    metricValues.put(ts - 100000, 2);
+    metricValues.put(ts - 80000, 40);
+    m1.setType(Type.TIME_SERIES);
+    m1.setValues(metricValues);
+    metrics.add(m1);
+
+    TimelineMetric m2 = new TimelineMetric();
+    m2.setId(metric2);
+    metricValues = new HashMap<Long, Number>();
+    ts = System.currentTimeMillis();
+    metricValues.put(ts - 100000, 31);
+    metricValues.put(ts - 80000, 57);
+    m2.setType(Type.TIME_SERIES);
+    m2.setValues(metricValues);
+    metrics.add(m2);
+
+    entity.addMetrics(metrics);
+    return entity;
+  }
+
+  static TimelineEntity getEntityMetricsApp2() {
+    TimelineEntity entity = new TimelineEntity();
+    String id = "flowRunMetrics_test";
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setId(id);
+    entity.setType(type);
+    Long cTime = 1425016501000L;
+    entity.setCreatedTime(cTime);
+    // add metrics
+    Set<TimelineMetric> metrics = new HashSet<>();
+    TimelineMetric m1 = new TimelineMetric();
+    m1.setId(metric1);
+    Map<Long, Number> metricValues = new HashMap<Long, Number>();
+    long ts = System.currentTimeMillis();
+    metricValues.put(ts - 100000, 5L);
+    metricValues.put(ts - 80000, 101L);
+    m1.setType(Type.TIME_SERIES);
+    m1.setValues(metricValues);
+    metrics.add(m1);
+    entity.addMetrics(metrics);
+    return entity;
+  }
+
+  static TimelineEntity getEntity1() {
+    TimelineEntity entity = new TimelineEntity();
+    String id = "flowRunHello";
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setId(id);
+    entity.setType(type);
+    Long cTime = 20000000000000L;
+    Long mTime = 1425026901000L;
+    entity.setCreatedTime(cTime);
+    entity.setModifiedTime(mTime);
+    // add metrics
+    Set<TimelineMetric> metrics = new HashSet<>();
+    TimelineMetric m1 = new TimelineMetric();
+    m1.setId(metric1);
+    Map<Long, Number> metricValues = new HashMap<Long, Number>();
+    long ts = System.currentTimeMillis();
+    metricValues.put(ts - 120000, 100000000);
+    metricValues.put(ts - 100000, 200000000);
+    metricValues.put(ts - 80000, 300000000);
+    metricValues.put(ts - 60000, 400000000);
+    metricValues.put(ts - 40000, 50000000000L);
+    metricValues.put(ts - 20000, 60000000000L);
+    m1.setType(Type.TIME_SERIES);
+    m1.setValues(metricValues);
+    metrics.add(m1);
+    entity.addMetrics(metrics);
+
+    TimelineEvent event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.CREATED_EVENT_TYPE);
+    Long expTs = 1436512802000L;
+    event.setTimestamp(expTs);
+    String expKey = "foo_event";
+    Object expVal = "test";
+    event.addInfo(expKey, expVal);
+    entity.addEvent(event);
+
+    event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.FINISHED_EVENT_TYPE);
+    event.setTimestamp(1436512801000L);
+    event.addInfo(expKey, expVal);
+    entity.addEvent(event);
+
+    return entity;
+  }
+
+  static TimelineEntity getEntityGreaterStartTime() {
+    TimelineEntity entity = new TimelineEntity();
+    entity.setCreatedTime(30000000000000L);
+    entity.setId("flowRunHello with greater start time");
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setType(type);
+    TimelineEvent event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.CREATED_EVENT_TYPE);
+    long endTs = 1439379885000L;
+    event.setTimestamp(endTs);
+    String expKey = "foo_event_greater";
+    String expVal = "test_app_greater";
+    event.addInfo(expKey, expVal);
+    entity.addEvent(event);
+    return entity;
+  }
+
+  static TimelineEntity getEntityMaxEndTime(long endTs) {
+    TimelineEntity entity = new TimelineEntity();
+    entity.setId("flowRunHello Max End time");
+    entity.setType(TimelineEntityType.YARN_APPLICATION.toString());
+    TimelineEvent event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.FINISHED_EVENT_TYPE);
+    event.setTimestamp(endTs);
+    String expKey = "foo_even_max_ finished";
+    String expVal = "test_app_max_finished";
+    event.addInfo(expKey, expVal);
+    entity.addEvent(event);
+    return entity;
+  }
+
+  static TimelineEntity getEntityMinStartTime() {
+    TimelineEntity entity = new TimelineEntity();
+    String id = "flowRunHelloMInStartTime";
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setId(id);
+    entity.setType(type);
+    Long cTime = 10000000000000L;
+    entity.setCreatedTime(cTime);
+    TimelineEvent event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.CREATED_EVENT_TYPE);
+    event.setTimestamp(System.currentTimeMillis());
+    entity.addEvent(event);
+    return entity;
+  }
+
+
+  static TimelineEntity getFlowApp1() {
+    TimelineEntity entity = new TimelineEntity();
+    String id = "flowActivity_test";
+    String type = TimelineEntityType.YARN_APPLICATION.toString();
+    entity.setId(id);
+    entity.setType(type);
+    Long cTime = 1425016501000L;
+    entity.setCreatedTime(cTime);
+
+    TimelineEvent event = new TimelineEvent();
+    event.setId(ApplicationMetricsConstants.CREATED_EVENT_TYPE);
+    Long expTs = 1436512802000L;
+    event.setTimestamp(expTs);
+    String expKey = "foo_event";
+    Object expVal = "test";
+    event.addInfo(expKey, expVal);
+    entity.addEvent(event);
+
+    return entity;
+  }
+
+}