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Posted to commits@crunch.apache.org by jw...@apache.org on 2017/04/13 07:28:38 UTC
crunch git commit: CRUNCH-642 Enable GroupingOptions for Distinct
operations.
Repository: crunch
Updated Branches:
refs/heads/master afc171fb7 -> ce9aaa3a5
CRUNCH-642 Enable GroupingOptions for Distinct operations.
This fixes the existing call for numReducers as it was not working as
intended for non-memory PCollections due to using an invalid amount
of numReducers. To increase flexibility when using the API,
another call was added that allow to directly pass the GroupingOptions.
Signed-off-by: Josh Wills <jw...@apache.org>
Project: http://git-wip-us.apache.org/repos/asf/crunch/repo
Commit: http://git-wip-us.apache.org/repos/asf/crunch/commit/ce9aaa3a
Tree: http://git-wip-us.apache.org/repos/asf/crunch/tree/ce9aaa3a
Diff: http://git-wip-us.apache.org/repos/asf/crunch/diff/ce9aaa3a
Branch: refs/heads/master
Commit: ce9aaa3a532a56ea52a698fcc259c2c3d5a21a6c
Parents: afc171f
Author: Xavier Talpe <xa...@ngdata.com>
Authored: Thu Apr 13 07:52:43 2017 +0200
Committer: Josh Wills <jw...@apache.org>
Committed: Wed Apr 12 23:13:55 2017 -0700
----------------------------------------------------------------------
.../java/org/apache/crunch/lib/DistinctIT.java | 58 ++++++++++++++++++++
.../java/org/apache/crunch/lib/Distinct.java | 32 ++++++++++-
crunch-test/src/main/resources/list.txt | 6 ++
3 files changed, 94 insertions(+), 2 deletions(-)
----------------------------------------------------------------------
http://git-wip-us.apache.org/repos/asf/crunch/blob/ce9aaa3a/crunch-core/src/it/java/org/apache/crunch/lib/DistinctIT.java
----------------------------------------------------------------------
diff --git a/crunch-core/src/it/java/org/apache/crunch/lib/DistinctIT.java b/crunch-core/src/it/java/org/apache/crunch/lib/DistinctIT.java
new file mode 100644
index 0000000..aba26fd
--- /dev/null
+++ b/crunch-core/src/it/java/org/apache/crunch/lib/DistinctIT.java
@@ -0,0 +1,58 @@
+/**
+ * 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
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
+ * 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.crunch.lib;
+
+import java.io.IOException;
+
+import org.apache.crunch.PCollection;
+import org.apache.crunch.Pipeline;
+import org.apache.crunch.impl.mr.MRPipeline;
+import org.apache.crunch.io.From;
+import org.apache.crunch.test.CrunchTestSupport;
+import org.apache.hadoop.fs.Path;
+import org.junit.Test;
+
+import com.google.common.collect.Lists;
+
+import static org.junit.Assert.assertEquals;
+
+public class DistinctIT extends CrunchTestSupport {
+
+ @Test
+ public void testDistinct() throws IOException {
+ Pipeline p = new MRPipeline(DistinctIT.class, tempDir.getDefaultConfiguration());
+ Path inputPath = tempDir.copyResourcePath("list.txt");
+ PCollection<String> in = p.read(From.textFile(inputPath));
+
+ PCollection<String> distinct = Distinct.distinct(in);
+
+ assertEquals(Lists.newArrayList("a", "b", "c", "d"), Lists.newArrayList(distinct.materialize()));
+ }
+
+ @Test
+ public void testDistinctWithExplicitNumReducers() throws IOException {
+ Pipeline p = new MRPipeline(DistinctIT.class, tempDir.getDefaultConfiguration());
+ Path inputPath = tempDir.copyResourcePath("list.txt");
+ PCollection<String> in = p.read(From.textFile(inputPath));
+
+ PCollection<String> distinct = Distinct.distinct(in, 50, 1);
+
+ assertEquals(Lists.newArrayList("a", "b", "c", "d"), Lists.newArrayList(distinct.materialize()));
+ }
+
+}
http://git-wip-us.apache.org/repos/asf/crunch/blob/ce9aaa3a/crunch-core/src/main/java/org/apache/crunch/lib/Distinct.java
----------------------------------------------------------------------
diff --git a/crunch-core/src/main/java/org/apache/crunch/lib/Distinct.java b/crunch-core/src/main/java/org/apache/crunch/lib/Distinct.java
index dd73d37..6b55329 100644
--- a/crunch-core/src/main/java/org/apache/crunch/lib/Distinct.java
+++ b/crunch-core/src/main/java/org/apache/crunch/lib/Distinct.java
@@ -21,6 +21,7 @@ import java.util.Set;
import org.apache.crunch.DoFn;
import org.apache.crunch.Emitter;
+import org.apache.crunch.GroupingOptions;
import org.apache.crunch.PCollection;
import org.apache.crunch.PTable;
import org.apache.crunch.Pair;
@@ -45,7 +46,7 @@ public final class Distinct {
* @return A new {@code PCollection} that contains the unique elements of the input
*/
public static <S> PCollection<S> distinct(PCollection<S> input) {
- return distinct(input, DEFAULT_FLUSH_EVERY, 0);
+ return distinct(input, DEFAULT_FLUSH_EVERY, GroupingOptions.builder().build());
}
/**
@@ -65,7 +66,7 @@ public final class Distinct {
* @return A new {@code PCollection} that contains the unique elements of the input
*/
public static <S> PCollection<S> distinct(PCollection<S> input, int flushEvery) {
- return distinct(input, flushEvery, 0);
+ return distinct(input, flushEvery, GroupingOptions.builder().build());
}
/**
@@ -101,6 +102,33 @@ public final class Distinct {
return PTables.asPTable(distinct((PCollection<Pair<K, V>>) input, flushEvery, numReducers));
}
+ /**
+ * A {@code distinct} operation that gives the client more control over how frequently
+ * elements are flushed to disk in order to allow control over performance or
+ * memory consumption.
+ *
+ * @param input The input {@code PCollection}
+ * @param flushEvery Flush the elements to disk whenever we encounter this many unique values
+ * @param options Options to provide finer control on how grouping is performed.
+ * @return A new {@code PCollection} that contains the unique elements of the input
+ */
+ public static <S> PCollection<S> distinct(PCollection<S> input, int flushEvery, GroupingOptions options) {
+ Preconditions.checkArgument(flushEvery > 0);
+ PType<S> pt = input.getPType();
+ PTypeFamily ptf = pt.getFamily();
+ return input
+ .parallelDo("pre-distinct", new PreDistinctFn<S>(flushEvery, pt), ptf.tableOf(pt, ptf.nulls()))
+ .groupByKey(options)
+ .parallelDo("post-distinct", new PostDistinctFn<S>(), pt);
+ }
+
+ /**
+ * A {@code PTable<K, V>} analogue of the {@code distinct} function.
+ */
+ public static <K, V> PTable<K, V> distinct(PTable<K, V> input, int flushEvery, GroupingOptions options) {
+ return PTables.asPTable(distinct((PCollection<Pair<K, V>>) input, flushEvery, options));
+ }
+
private static class PreDistinctFn<S> extends DoFn<S, Pair<S, Void>> {
private final Set<S> values = Sets.newHashSet();
private final int flushEvery;
http://git-wip-us.apache.org/repos/asf/crunch/blob/ce9aaa3a/crunch-test/src/main/resources/list.txt
----------------------------------------------------------------------
diff --git a/crunch-test/src/main/resources/list.txt b/crunch-test/src/main/resources/list.txt
new file mode 100644
index 0000000..aad3ed8
--- /dev/null
+++ b/crunch-test/src/main/resources/list.txt
@@ -0,0 +1,6 @@
+a
+b
+c
+a
+d
+c