/**
* 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.drill.exec.store.easy.json;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;
import com.google.common.collect.Lists;
import org.apache.drill.common.exceptions.ExecutionSetupException;
import org.apache.drill.common.exceptions.UserException;
import org.apache.drill.common.expression.SchemaPath;
import org.apache.drill.exec.ExecConstants;
import org.apache.drill.exec.exception.OutOfMemoryException;
import org.apache.drill.exec.ops.FragmentContext;
import org.apache.drill.exec.ops.OperatorContext;
import org.apache.drill.exec.physical.impl.OutputMutator;
import org.apache.drill.exec.store.AbstractRecordReader;
import org.apache.drill.exec.store.dfs.DrillFileSystem;
import org.apache.drill.exec.store.easy.json.JsonProcessor.ReadState;
import org.apache.drill.exec.store.easy.json.reader.CountingJsonReader;
import org.apache.drill.exec.vector.BaseValueVector;
import org.apache.drill.exec.vector.complex.fn.JsonReader;
import org.apache.drill.exec.vector.complex.impl.VectorContainerWriter;
import org.apache.hadoop.fs.Path;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonNode;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
public class JSONRecordReader extends AbstractRecordReader {
private static final org.slf4j.Logger logger = org.slf4j.LoggerFactory.getLogger(JSONRecordReader.class);
public static final long DEFAULT_ROWS_PER_BATCH = BaseValueVector.INITIAL_VALUE_ALLOCATION;
private VectorContainerWriter writer;
// Data we're consuming
private Path hadoopPath;
private JsonNode embeddedContent;
private InputStream stream;
private final DrillFileSystem fileSystem;
private JsonProcessor jsonReader;
private int recordCount;
private long runningRecordCount = 0;
private final FragmentContext fragmentContext;
private final boolean enableAllTextMode;
private final boolean readNumbersAsDouble;
private final boolean unionEnabled;
private long parseErrorCount;
private final boolean skipMalformedJSONRecords;
private final boolean printSkippedMalformedJSONRecordLineNumber;
ReadState write = null;
/**
* Create a JSON Record Reader that uses a file based input stream.
* @param fragmentContext
* @param inputPath
* @param fileSystem
* @param columns pathnames of columns/subfields to read
* @throws OutOfMemoryException
*/
public JSONRecordReader(final FragmentContext fragmentContext, final String inputPath, final DrillFileSystem fileSystem,
final List<SchemaPath> columns) throws OutOfMemoryException {
this(fragmentContext, inputPath, null, fileSystem, columns);
}
/**
* Create a new JSON Record Reader that uses a in memory materialized JSON stream.
* @param fragmentContext
* @param embeddedContent
* @param fileSystem
* @param columns pathnames of columns/subfields to read
* @throws OutOfMemoryException
*/
public JSONRecordReader(final FragmentContext fragmentContext, final JsonNode embeddedContent,
final DrillFileSystem fileSystem, final List<SchemaPath> columns) throws OutOfMemoryException {
this(fragmentContext, null, embeddedContent, fileSystem, columns);
}
private JSONRecordReader(final FragmentContext fragmentContext, final String inputPath,
final JsonNode embeddedContent, final DrillFileSystem fileSystem,
final List<SchemaPath> columns) {
Preconditions.checkArgument(
(inputPath == null && embeddedContent != null) ||
(inputPath != null && embeddedContent == null),
"One of inputPath or embeddedContent must be set but not both."
);
if(inputPath != null) {
this.hadoopPath = new Path(inputPath);
} else {
this.embeddedContent = embeddedContent;
}
this.fileSystem = fileSystem;
this.fragmentContext = fragmentContext;
// only enable all text mode if we aren't using embedded content mode.
this.enableAllTextMode = embeddedContent == null && fragmentContext.getOptions().getOption(ExecConstants.JSON_READER_ALL_TEXT_MODE_VALIDATOR);
this.readNumbersAsDouble = embeddedContent == null && fragmentContext.getOptions().getOption(ExecConstants.JSON_READ_NUMBERS_AS_DOUBLE_VALIDATOR);
this.unionEnabled = embeddedContent == null && fragmentContext.getOptions().getOption(ExecConstants.ENABLE_UNION_TYPE);
this.skipMalformedJSONRecords = fragmentContext.getOptions().getOption(ExecConstants.JSON_SKIP_MALFORMED_RECORDS_VALIDATOR);
this.printSkippedMalformedJSONRecordLineNumber = fragmentContext.getOptions().getOption(ExecConstants.JSON_READER_PRINT_INVALID_RECORDS_LINE_NOS_FLAG_VALIDATOR);
setColumns(columns);
}
@Override
public String toString() {
return super.toString()
+ "[hadoopPath = " + hadoopPath
+ ", recordCount = " + recordCount
+ ", parseErrorCount = " + parseErrorCount
+ ", runningRecordCount = " + runningRecordCount + ", ...]";
}
@Override
public void setup(final OperatorContext context, final OutputMutator output) throws ExecutionSetupException {
try{
if (hadoopPath != null) {
this.stream = fileSystem.openPossiblyCompressedStream(hadoopPath);
}
this.writer = new VectorContainerWriter(output, unionEnabled);
if (isSkipQuery()) {
this.jsonReader = new CountingJsonReader(fragmentContext.getManagedBuffer());
} else {
this.jsonReader = new JsonReader(fragmentContext.getManagedBuffer(), ImmutableList.copyOf(getColumns()), enableAllTextMode, true, readNumbersAsDouble);
}
setupParser();
}catch(final Exception e){
handleAndRaise("Failure reading JSON file", e);
}
}
@Override
protected List<SchemaPath> getDefaultColumnsToRead() {
return ImmutableList.of();
}
private void setupParser() throws IOException {
if(hadoopPath != null){
jsonReader.setSource(stream);
}else{
jsonReader.setSource(embeddedContent);
}
jsonReader.setIgnoreJSONParseErrors(skipMalformedJSONRecords);
}
protected void handleAndRaise(String suffix, Exception e) throws UserException {
String message = e.getMessage();
int columnNr = -1;
if (e instanceof JsonParseException) {
final JsonParseException ex = (JsonParseException) e;
message = ex.getOriginalMessage();
columnNr = ex.getLocation().getColumnNr();
}
UserException.Builder exceptionBuilder = UserException.dataReadError(e)
.message("%s - %s", suffix, message);
if (columnNr > 0) {
exceptionBuilder.pushContext("Column ", columnNr);
}
if (hadoopPath != null) {
exceptionBuilder.pushContext("Record ", currentRecordNumberInFile())
.pushContext("File ", hadoopPath.toUri().getPath());
}
throw exceptionBuilder.build(logger);
}
private long currentRecordNumberInFile() {
return runningRecordCount + recordCount + 1;
}
@Override
public int next() {
writer.allocate();
writer.reset();
recordCount = 0;
parseErrorCount = 0;
if(write == ReadState.JSON_RECORD_PARSE_EOF_ERROR){
return recordCount;
}
outside: while(recordCount < DEFAULT_ROWS_PER_BATCH){
try{
writer.setPosition(recordCount);
write = jsonReader.write(writer);
if(write == ReadState.WRITE_SUCCEED){
recordCount++;
}
else if(write == ReadState.JSON_RECORD_PARSE_ERROR || write == ReadState.JSON_RECORD_PARSE_EOF_ERROR){
if(skipMalformedJSONRecords == false){
handleAndRaise("Error parsing JSON", new Exception(hadoopPath.getName() + " : line nos :" + (recordCount+1)));
}
++parseErrorCount;
if(printSkippedMalformedJSONRecordLineNumber){
logger.debug("Error parsing JSON in " + hadoopPath.getName() + " : line nos :" + (recordCount+parseErrorCount));
}
if(write == ReadState.JSON_RECORD_PARSE_EOF_ERROR){
break outside;
}
}
else{
break outside;
}
}
catch(IOException ex)
{
handleAndRaise("Error parsing JSON", ex);
}
}
jsonReader.ensureAtLeastOneField(writer);
writer.setValueCount(recordCount);
updateRunningCount();
return recordCount;
}
private void updateRunningCount() {
runningRecordCount += recordCount;
}
@Override
public void close() throws Exception {
if(stream != null) {
stream.close();
}
}
}