You are viewing a plain text version of this content. The canonical link for it is here.
Posted to github@beam.apache.org by GitBox <gi...@apache.org> on 2020/05/05 21:31:37 UTC
[GitHub] [beam] robertwb commented on a change in pull request #11610: [BEAM-9825] | Implement Intersect,Union,Except transforms
robertwb commented on a change in pull request #11610:
URL: https://github.com/apache/beam/pull/11610#discussion_r420415887
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * both pipeline is constructed and provided {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersect(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m -
+ * n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersectAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} but not present in provided {@link
+ * PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.except(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> except(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L;
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll)
+ * with provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m
+ * elements of left for all elements which are present in left but not in right. - it will output
+ * MAX(m - n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.exceptAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> {
+ if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) {
+ return numberOfElementsinLeft;
+ } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) {
+ return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L);
+ }
+ return 0L;
+ };
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code
+ * PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.union(right));
+ * }</pre>
Review comment:
For all of these, it'd be useful to document what the expected output is.
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * both pipeline is constructed and provided {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersect(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m -
+ * n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersectAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} but not present in provided {@link
+ * PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.except(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> except(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L;
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll)
+ * with provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m
+ * elements of left for all elements which are present in left but not in right. - it will output
+ * MAX(m - n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.exceptAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> {
+ if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) {
+ return numberOfElementsinLeft;
+ } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) {
+ return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L);
+ }
+ return 0L;
+ };
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code
+ * PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.union(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> union(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> unionFn = (numberOfElementsinLeft, numberOfElementsinRight) -> 1L;
+ return new SetImpl<>(rightCollection, unionFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the unionAll with provided
Review comment:
Isn't this just `Flatten.pcollections`? (Also, isn't that more efficient?)
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * both pipeline is constructed and provided {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersect(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m -
+ * n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersectAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} but not present in provided {@link
+ * PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.except(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> except(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L;
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll)
+ * with provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m
+ * elements of left for all elements which are present in left but not in right. - it will output
+ * MAX(m - n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.exceptAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> {
+ if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) {
+ return numberOfElementsinLeft;
+ } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) {
+ return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L);
Review comment:
Isn't this expression always sufficient?
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
Review comment:
Though not as chain-able, a `PTransform<PCollectionList<T>, PCollection<T>>` feels more natural for many of these operations.
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * both pipeline is constructed and provided {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersect(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m -
+ * n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersectAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L;
Review comment:
Is not `Math.min(numberOfElementsinLeft, numberOfElementsinRight)` sufficient?
##########
File path: sdks/java/core/src/main/java/org/apache/beam/sdk/transforms/SetFns.java
##########
@@ -0,0 +1,261 @@
+/*
+ * 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.beam.sdk.transforms;
+
+import static org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Preconditions.checkNotNull;
+
+import org.apache.beam.sdk.transforms.join.CoGbkResult;
+import org.apache.beam.sdk.transforms.join.CoGroupByKey;
+import org.apache.beam.sdk.transforms.join.KeyedPCollectionTuple;
+import org.apache.beam.sdk.values.KV;
+import org.apache.beam.sdk.values.PCollection;
+import org.apache.beam.sdk.values.TupleTag;
+import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.Iterables;
+
+public class SetFns {
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * both pipeline is constructed and provided {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersect(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersect(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? 1L : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the intersection all with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output MIN(m -
+ * n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.intersectAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> intersectAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> intersectFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) ? Math.min(numberOfElementsinLeft, numberOfElementsinRight) : 0L;
+ return new SetImpl<>(rightCollection, intersectFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference (except) with
+ * provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} but not present in provided {@link
+ * PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.except(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> except(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> numberOfElementsinLeft > 0 && numberOfElementsinRight == 0 ? 1L : 0L;
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the difference all (exceptAll)
+ * with provided {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow EXCEPT_ALL Semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m
+ * elements of left for all elements which are present in left but not in right. - it will output
+ * MAX(m - n, 0) elements of left for all elements which are present in both left and right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.exceptAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> exceptAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> exceptFn =
+ (numberOfElementsinLeft, numberOfElementsinRight) -> {
+ if (numberOfElementsinLeft > 0 && numberOfElementsinRight == 0) {
+ return numberOfElementsinLeft;
+ } else if (numberOfElementsinLeft > 0 && numberOfElementsinRight > 0) {
+ return Math.max(numberOfElementsinLeft - numberOfElementsinRight, 0L);
+ }
+ return 0L;
+ };
+ return new SetImpl<>(rightCollection, exceptFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the union with provided {@code
+ * PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} will all distinct elements that present in
+ * pipeline is constructed {@link PCollection<T>} and {@link PCollection<T>}.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.union(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> union(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> unionFn = (numberOfElementsinLeft, numberOfElementsinRight) -> 1L;
+ return new SetImpl<>(rightCollection, unionFn);
+ }
+
+ /**
+ * Returns a new {@code SetFns.SetImpl<T>} transform that compute the unionAll with provided
+ * {@code PCollection<T>}.
+ *
+ * <p>The argument should not be modified after this is called.
+ *
+ * <p>The elements of the output {@link PCollection<T>} which will follow UNION_ALL semantics as
+ * follows: Given there are m elements on pipeline which is constructed {@link PCollection<T>}
+ * (left) and n elements on in provided {@link PCollection<T>} (right): - it will output m
+ * elements of left and m elements of right.
+ *
+ * <pre>{@code
+ * Pipeline p = ...;
+ *
+ * PCollection<String> left = p.apply(Create.of("1", "2", "3", "4", "5"));
+ * PCollection<String> right = p.apply(Create.of("1", "3", "4", "6"));
+ *
+ * PCollection<String> results =
+ * left.apply(SetFns.unionAll(right));
+ * }</pre>
+ */
+ public static <T> SetImpl<T> unionAll(PCollection<T> rightCollection) {
+ checkNotNull(rightCollection, "rightCollection argument is null");
+ SerializableBiFunction<Long, Long, Long> unionFn = Long::sum;
+ return new SetImpl<>(rightCollection, unionFn);
+ }
+
+ private static <T> PCollection<T> performSetOperation(
+ PCollection<T> leftCollection,
+ PCollection<T> rightCollection,
+ SerializableBiFunction<Long, Long, Long> fn) {
+
+ TupleTag<Void> leftCollectionTag = new TupleTag<>();
+ TupleTag<Void> rightCollectionTag = new TupleTag<>();
+
+ MapElements<T, KV<T, Void>> elementToVoid =
+ MapElements.via(
+ new SimpleFunction<T, KV<T, Void>>() {
+ @Override
+ public KV<T, Void> apply(T element) {
+ return KV.of(element, null);
+ }
+ });
+
+ PCollection<KV<T, Void>> left = leftCollection.apply("PrepareLeftKV", elementToVoid);
+ PCollection<KV<T, Void>> right = rightCollection.apply("PrepareRightKV", elementToVoid);
+
+ PCollection<KV<T, CoGbkResult>> coGbkResults =
+ KeyedPCollectionTuple.of(leftCollectionTag, left)
+ .and(rightCollectionTag, right)
+ .apply(CoGroupByKey.create());
+
+ return coGbkResults.apply(
+ ParDo.of(
+ new DoFn<KV<T, CoGbkResult>, T>() {
+
+ @ProcessElement
+ public void processElement(ProcessContext c) {
+ KV<T, CoGbkResult> elementGroups = c.element();
+
+ CoGbkResult value = elementGroups.getValue();
Review comment:
I wonder if it's worth dropping at TODO here to lift combiners through the CoGBK.
----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
For queries about this service, please contact Infrastructure at:
users@infra.apache.org