/**
* 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.avro.tool;
import java.io.IOException;
import java.io.InputStream;
import java.io.PrintStream;
import java.util.List;
import java.util.Map;
import org.apache.trevni.Input;
import org.apache.trevni.ColumnFileReader;
import org.apache.trevni.MetaData;
import org.apache.trevni.ColumnMetaData;
import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonGenerator;
import org.codehaus.jackson.JsonEncoding;
import org.codehaus.jackson.util.MinimalPrettyPrinter;
/** Tool to print Trevni file metadata as JSON. */
public class TrevniMetadataTool implements Tool {
static final JsonFactory FACTORY = new JsonFactory();
private JsonGenerator generator;
private ColumnFileReader reader;
@Override
public String getName() {
return "trevni_meta";
}
@Override
public String getShortDescription() {
return "Dumps a Trevni file's metadata as JSON.";
}
@Override
public int run(InputStream stdin, PrintStream out, PrintStream err,
List<String> args) throws Exception {
String filename;
boolean pretty = false;
if (args.size() == 2 && "-pretty".equals(args.get(0))) {
pretty = true;
filename = args.get(1);
} else if (args.size() == 1) {
filename = args.get(0);
} else {
err.println("Usage: [-pretty] input");
return 1;
}
dump(TrevniUtil.input(filename), out, pretty);
return 0;
}
/** Read a Trevni file and print each row as a JSON object. */
public void dump(Input input, PrintStream out, boolean pretty)
throws IOException {
this.generator = FACTORY.createJsonGenerator(out, JsonEncoding.UTF8);
if (pretty) {
generator.useDefaultPrettyPrinter();
} else { // ensure newline separation
MinimalPrettyPrinter pp = new MinimalPrettyPrinter();
pp.setRootValueSeparator(System.getProperty("line.separator"));
generator.setPrettyPrinter(pp);
}
this.reader = new ColumnFileReader(input);
generator.writeStartObject();
generator.writeNumberField("rowCount", reader.getRowCount());
generator.writeNumberField("columnCount", reader.getColumnCount());
generator.writeFieldName("metadata");
dump(reader.getMetaData());
generator.writeFieldName("columns");
generator.writeStartArray();
for (ColumnMetaData c : reader.getColumnMetaData())
dump(c);
generator.writeEndArray();
generator.writeEndObject();
generator.flush();
out.println();
reader.close();
}
private void dump(MetaData<?> meta) throws IOException {
generator.writeStartObject();
for (Map.Entry<String,byte[]> e : meta.entrySet())
generator.writeStringField(e.getKey(),
new String(e.getValue(), "ISO-8859-1"));
generator.writeEndObject();
}
}