Github user vasia commented on a diff in the pull request:
https://github.com/apache/flink/pull/1149#discussion_r39948692
--- Diff:
flink-staging/flink-gelly/src/main/java/org/apache/flink/graph/GraphCsvReader.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.flink.graph;
+import com.google.common.base.Preconditions;
+
+import org.apache.flink.api.common.functions.MapFunction;
+import org.apache.flink.api.java.DataSet;
+import org.apache.flink.api.java.io.CsvReader;
+import org.apache.flink.api.java.tuple.Tuple2;
+import org.apache.flink.api.java.tuple.Tuple3;
+import org.apache.flink.core.fs.Path;
+import org.apache.flink.types.NullValue;
+import org.apache.flink.api.java.ExecutionEnvironment;
+
+/**
+ * A class to build a Graph using path(s) provided to CSV file(s) with
optional vertex and edge data.
+ * The class also configures the CSV readers used to read edge and vertex
data such as the field types,
+ * the delimiters (row and field), the fields that should be included or
skipped, and other flags,
+ * such as whether to skip the initial line as the header.
+ * The configuration is done using the functions provided in the {@link
org.apache.flink.api.java.io.CsvReader} class.
+ */
+
+public class GraphCsvReader {
+
+ @SuppressWarnings("unused")
+ private final Path vertexPath, edgePath;
+ private final ExecutionEnvironment executionContext;
+ protected CsvReader edgeReader;
+ protected CsvReader vertexReader;
+ protected MapFunction<?, ?> mapper;
+ protected Class<?> vertexKey;
+ protected Class<?> vertexValue;
+ protected Class<?> edgeValue;
+
+//--------------------------------------------------------------------------------------------------------------------
+ public GraphCsvReader(Path vertexPath, Path edgePath,
ExecutionEnvironment context) {
+ this.vertexPath = vertexPath;
+ this.edgePath = edgePath;
+ this.vertexReader = new CsvReader(vertexPath, context);
+ this.edgeReader = new CsvReader(edgePath, context);
+ this.mapper = null;
+ this.executionContext = context;
+ }
+
+ public GraphCsvReader(Path edgePath, ExecutionEnvironment context) {
+ this.vertexPath = null;
+ this.edgePath = edgePath;
+ this.edgeReader = new CsvReader(edgePath, context);
+ this.vertexReader = null;
+ this.mapper = null;
+ this.executionContext = context;
+ }
+
+ public <K, VV> GraphCsvReader(Path edgePath, final MapFunction<K, VV>
mapper, ExecutionEnvironment context) {
+ this.vertexPath = null;
+ this.edgePath = edgePath;
+ this.edgeReader = new CsvReader(edgePath, context);
+ this.vertexReader = null;
+ this.mapper = mapper;
+ this.executionContext = context;
+ }
+
+ public GraphCsvReader (String edgePath, ExecutionEnvironment context) {
+ this(new Path(Preconditions.checkNotNull(edgePath, "The file
path may not be null.")), context);
+
+ }
+
+ public GraphCsvReader(String vertexPath, String edgePath,
ExecutionEnvironment context) {
+ this(new Path(Preconditions.checkNotNull(vertexPath, "The file
path may not be null.")),
+ new Path(Preconditions.checkNotNull(edgePath,
"The file path may not be null.")), context);
+ }
+
+
+ public <K, VV> GraphCsvReader(String edgePath, final MapFunction<K, VV>
mapper, ExecutionEnvironment context) {
+ this(new Path(Preconditions.checkNotNull(edgePath, "The
file path may not be null.")), mapper, context);
+ }
+
+ /**
+ * Creates a Graph from CSV input with vertex values and edge values.
+ * The vertex values are specified through a vertices input file or a
user-defined map function.
+ *
+ * @param vertexKey the type of the vertex IDs
+ * @param vertexValue the type of the vertex values
+ * @param edgeValue the type of the edge values
+ * @return a Graph with vertex and edge values.
+ */
+ @SuppressWarnings("unchecked")
+ public <K, VV, EV> Graph<K, VV, EV> types(Class<K> vertexKey, Class<VV>
vertexValue,
+ Class<EV> edgeValue) {
+
+ DataSet<Tuple2<K, VV>> vertices = null;
+
+ if (edgeReader == null) {
+ throw new RuntimeException("The edges input file cannot
be null!");
+ }
+
+ DataSet<Tuple3<K, K, EV>> edges = edgeReader.types(vertexKey,
vertexKey, edgeValue);
+
+ // the vertex value can be provided by an input file or a
user-defined mapper
+ if (vertexReader != null) {
+ vertices = vertexReader.types(vertexKey, vertexValue);
+ return Graph.fromTupleDataSet(vertices, edges,
executionContext);
+ }
+ else if (mapper != null) {
+ return Graph.fromTupleDataSet(edges, (MapFunction<K,
VV>) mapper, executionContext);
+ }
+ else {
+ throw new RuntimeException("Vertex values have to be
specified through a vertices input file"
+ + "or a user-defined map function.");
+ }
+ }
+
+ /**
+ * Creates a Graph from CSV input with edge values, but without vertex
values.
+ * @param vertexKey the type of the vertex IDs
+ * @param edgeValue the type of the edge values
+ * @return a Graph where the edges are read from an edges CSV file
(with values).
+ */
+ public <K, EV> Graph<K, NullValue, EV> edgeTypes(Class<K> vertexKey,
Class<EV> edgeValue) {
+
+ if (edgeReader == null) {
+ throw new RuntimeException("The edges input file cannot
be null!");
+ }
+
+ DataSet<Tuple3<K, K, EV>> edges = edgeReader.types(vertexKey,
vertexKey, edgeValue);
+
+ return Graph.fromTupleDataSet(edges, executionContext);
+ }
+
+ /**
+ * Creates a Graph from CSV input without vertex values or edge values.
+ * @param vertexKey the type of the vertex IDs
+ * @return a Graph where the vertex IDs are read from the edges input
file.
+ */
+ public <K> Graph<K, NullValue, NullValue> keyType(Class<K> vertexKey) {
+
+ if (edgeReader == null) {
+ throw new RuntimeException("The edges input file cannot
be null!");
+ }
+
+ @SuppressWarnings("serial")
+ DataSet<Tuple3<K, K, NullValue>> edges =
edgeReader.types(vertexKey, vertexKey)
+ .map(new MapFunction<Tuple2<K, K>, Tuple3<K, K,
NullValue>>() {
+
+ public Tuple3<K, K, NullValue>
map(Tuple2<K, K> edge) {
+ return new Tuple3<K, K,
NullValue>(edge.f0, edge.f1, NullValue.getInstance());
--- End diff --
good catch! thnx!
---
If your project is set up for it, you can reply to this email and have your
reply appear on GitHub as well. If your project does not have this feature
enabled and wishes so, or if the feature is enabled but not working, please
contact infrastructure at infrastruct...@apache.org or file a JIRA ticket
with INFRA.
---
