github-actions[bot] opened a new issue, #297: URL: https://github.com/apache/incubator-wayang/issues/297
incorporate fields later for projectable table scans private final ImmutableIntList fields; https://github.com/apache/incubator-wayang/blob/d46f3c3f0fb963c2ee2640f00a106042fba55431/wayang-api/wayang-api-sql/src/main/java/org/apache/wayang/api/sql/sources/fs/JavaCSVTableSource.java#L56 ```java /* * 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.wayang.api.sql.sources.fs; import org.apache.calcite.rel.type.RelDataType; import org.apache.commons.io.IOUtils; import org.apache.wayang.basic.channels.FileChannel; import org.apache.wayang.basic.data.Record; import org.apache.wayang.core.api.exception.WayangException; import org.apache.wayang.core.optimizer.OptimizationContext; import org.apache.wayang.core.plan.wayangplan.ExecutionOperator; import org.apache.wayang.core.plan.wayangplan.UnarySource; import org.apache.wayang.core.platform.ChannelDescriptor; import org.apache.wayang.core.platform.ChannelInstance; import org.apache.wayang.core.platform.lineage.ExecutionLineageNode; import org.apache.wayang.core.types.DataSetType; import org.apache.wayang.core.util.Tuple; import org.apache.wayang.core.util.fs.FileSystem; import org.apache.wayang.core.util.fs.FileSystems; import org.apache.wayang.core.util.fs.FileUtils; import org.apache.wayang.java.channels.StreamChannel; import org.apache.wayang.java.execution.JavaExecutor; import org.apache.wayang.java.operators.JavaExecutionOperator; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.UncheckedIOException; import java.util.*; import java.util.function.Function; import java.util.stream.Stream; import java.util.stream.StreamSupport; public class JavaCSVTableSource<T> extends UnarySource<T> implements JavaExecutionOperator { private final String sourcePath; private final List<RelDataType> fieldTypes; // TODO: incorporate fields later for projectable table scans // private final ImmutableIntList fields; public JavaCSVTableSource(String sourcePath, DataSetType type, List<RelDataType> fieldTypes) { super(type); this.sourcePath = sourcePath; this.fieldTypes = fieldTypes; } /*public JavaCSVTableSource(DataSetType<T> type) { this(null, type); }*/ @Override public Tuple<Collection<ExecutionLineageNode>, Collection<ChannelInstance>> evaluate( ChannelInstance[] inputs, ChannelInstance[] outputs, JavaExecutor javaExecutor, OptimizationContext.OperatorContext operatorContext) { assert outputs.length == this.getNumOutputs(); final String path; if (this.sourcePath == null) { final FileChannel.Instance input = (FileChannel.Instance) inputs[0]; path = input.getSinglePath(); } else { assert inputs.length == 0; path = this.sourcePath; } final String actualInputPath = FileSystems.findActualSingleInputPath(path); Stream<T> stream = this.createStream(actualInputPath); ((StreamChannel.Instance) outputs[0]).accept(stream); return ExecutionOperator.modelLazyExecution(inputs, outputs, operatorContext); } private Stream<T> createStream(String actualInputPath) { Function<String, T> parser = this::parseLine; return streamLines(actualInputPath).map(parser); } private T parseLine(String s) { Class typeClass = this.getType().getDataUnitType().getTypeClass(); assert typeClass == Record.class; try { String[] tokens = CsvRowConverter.parseLine(s); if (tokens.length != fieldTypes.size()) { throw new IllegalStateException(String.format("Error while parsing CSV file %s at line %s", sourcePath, s)); } final Object[] objects = new Object[tokens.length]; for (int i = 0; i < tokens.length; i++) { objects[i] = CsvRowConverter.convert(fieldTypes.get(i), tokens[i]); } return (T) new Record(objects); } catch (IOException e) { System.out.println(e.getMessage()); } throw new IllegalStateException(String.format("Error while parsing CSV file %s at line %s", sourcePath, s)); } @Override public List<ChannelDescriptor> getSupportedInputChannels(int index) { return Collections.singletonList(FileChannel.HDFS_TSV_DESCRIPTOR); } @Override public List<ChannelDescriptor> getSupportedOutputChannels(int index) { assert index <= this.getNumOutputs() || (index == 0 && this.getNumOutputs() == 0); return Collections.singletonList(StreamChannel.DESCRIPTOR); } /** * Copied from {@link FileUtils} as a quick work around to read CSV file after skipping * header row. * * Creates a {@link Stream} of a lines of the file. * * @param path of the file * @return the {@link Stream} */ private static Stream<String> streamLines(String path) { final FileSystem fileSystem = FileSystems.getFileSystem(path).orElseThrow( () -> new IllegalStateException(String.format("No file system found for %s", path)) ); try { Iterator<String> lineIterator = createLineIterator(fileSystem, path); lineIterator.next(); // skip header row return StreamSupport.stream(Spliterators.spliteratorUnknownSize(lineIterator, 0), false); } catch (IOException e) { throw new WayangException(String.format("%s failed to read %s.", FileUtils.class, path), e); } } /** * Creates an {@link Iterator} over the lines of a given {@code path} (that resides in the given {@code fileSystem}). */ private static Iterator<String> createLineIterator(FileSystem fileSystem, String path) throws IOException { final BufferedReader reader = new BufferedReader(new InputStreamReader(fileSystem.open(path), "UTF-8")); return new Iterator<String>() { String next; { this.advance(); } private void advance() { try { this.next = reader.readLine(); } catch (IOException e) { this.next = null; throw new UncheckedIOException(e); } finally { if (this.next == null) { IOUtils.closeQuietly(reader); } } } @Override public boolean hasNext() { return this.next != null; } @Override public String next() { assert this.hasNext(); final String returnValue = this.next; this.advance(); return returnValue; } }; } } ``` 2b1aef4e9a7503c7e7f9987af1737a27fe565f78 -- This is an automated message from the Apache Git Service. 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