| /** |
| * 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 com.datatorrent.contrib.parser; |
| |
| import java.io.IOException; |
| import java.util.Iterator; |
| |
| import org.codehaus.jettison.json.JSONException; |
| import org.codehaus.jettison.json.JSONObject; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import org.apache.hadoop.classification.InterfaceStability; |
| |
| import com.fasterxml.jackson.databind.DeserializationFeature; |
| import com.fasterxml.jackson.databind.JsonNode; |
| import com.fasterxml.jackson.databind.ObjectMapper; |
| import com.github.fge.jackson.JsonLoader; |
| import com.github.fge.jsonschema.core.exceptions.ProcessingException; |
| import com.github.fge.jsonschema.core.report.ProcessingMessage; |
| import com.github.fge.jsonschema.core.report.ProcessingReport; |
| import com.github.fge.jsonschema.main.JsonSchema; |
| import com.github.fge.jsonschema.main.JsonSchemaFactory; |
| import com.google.common.annotations.VisibleForTesting; |
| |
| import com.datatorrent.api.AutoMetric; |
| import com.datatorrent.api.Context.OperatorContext; |
| import com.datatorrent.api.DefaultOutputPort; |
| import com.datatorrent.lib.parser.Parser; |
| import com.datatorrent.lib.util.KeyValPair; |
| import com.datatorrent.netlet.util.DTThrowable; |
| |
| /** |
| * Operator that parses a json string tuple against a specified json schema and |
| * emits JSONObject on one port, POJO on other port and tuples that could not be |
| * parsed on error port.<br> |
| * Schema is specified in a json format as per http://json-schema.org/ <br> |
| * Example for the schema can be seen here http://json-schema.org/example1.html <br> |
| * User can choose to skip validations by not specifying the schema at all. <br> |
| * <br> |
| * <b>Properties</b><br> |
| * <b>jsonSchema</b>:schema as a string<br> |
| * <b>clazz</b>:Pojo class <br> |
| * <b>Ports</b> <br> |
| * <b>in</b>:input tuple as a String. Each tuple represents a json string<br> |
| * <b>parsedOutput</b>:tuples that are validated against the schema are emitted |
| * as JSONObject on this port<br> |
| * <b>out</b>:tuples that are validated against the schema are emitted as pojo |
| * on this port<br> |
| * <b>err</b>:tuples that do not confine to schema are emitted on this port as |
| * KeyValPair<String,String><br> |
| * Key being the tuple and Val being the reason. |
| * |
| * |
| * @displayName JsonParser |
| * @category Parsers |
| * @tags json pojo parser |
| * @since 3.2.0 |
| */ |
| @InterfaceStability.Evolving |
| public class JsonParser extends Parser<byte[], KeyValPair<String, String>> |
| { |
| |
| /** |
| * Contents of the schema.Schema is specified as per http://json-schema.org/ |
| */ |
| private String jsonSchema; |
| private transient JsonSchema schema; |
| private transient ObjectMapper objMapper; |
| /** |
| * output port to emit validate records as JSONObject |
| */ |
| public transient DefaultOutputPort<JSONObject> parsedOutput = new DefaultOutputPort<JSONObject>(); |
| /** |
| * metric to keep count of number of tuples emitted on {@link #parsedOutput} |
| * port |
| */ |
| @AutoMetric |
| long parsedOutputCount; |
| |
| @Override |
| public void beginWindow(long windowId) |
| { |
| super.beginWindow(windowId); |
| parsedOutputCount = 0; |
| } |
| |
| @Override |
| public void setup(OperatorContext context) |
| { |
| try { |
| if (jsonSchema != null) { |
| JsonSchemaFactory factory = JsonSchemaFactory.byDefault(); |
| JsonNode schemaNode = JsonLoader.fromString(jsonSchema); |
| schema = factory.getJsonSchema(schemaNode); |
| } |
| objMapper = new ObjectMapper(); |
| objMapper.disable(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES); |
| } catch (ProcessingException | IOException e) { |
| DTThrowable.wrapIfChecked(e); |
| } |
| } |
| |
| @Override |
| public void processTuple(byte[] tuple) |
| { |
| if (tuple == null) { |
| if (err.isConnected()) { |
| err.emit(new KeyValPair<String, String>(null, "null tuple")); |
| } |
| errorTupleCount++; |
| return; |
| } |
| String incomingString = new String(tuple); |
| try { |
| if (schema != null) { |
| ProcessingReport report = null; |
| JsonNode data = JsonLoader.fromString(incomingString); |
| report = schema.validate(data); |
| if (report != null && !report.isSuccess()) { |
| Iterator<ProcessingMessage> iter = report.iterator(); |
| StringBuilder s = new StringBuilder(); |
| while (iter.hasNext()) { |
| ProcessingMessage pm = iter.next(); |
| s.append(pm.asJson().get("instance").findValue("pointer")).append(":").append(pm.asJson().get("message")) |
| .append(","); |
| } |
| s.setLength(s.length() - 1); |
| errorTupleCount++; |
| if (err.isConnected()) { |
| err.emit(new KeyValPair<String, String>(incomingString, s.toString())); |
| } |
| return; |
| } |
| } |
| if (parsedOutput.isConnected()) { |
| parsedOutput.emit(new JSONObject(incomingString)); |
| parsedOutputCount++; |
| } |
| if (out.isConnected()) { |
| out.emit(objMapper.readValue(tuple, clazz)); |
| emittedObjectCount++; |
| } |
| } catch (JSONException | ProcessingException | IOException e) { |
| errorTupleCount++; |
| if (err.isConnected()) { |
| err.emit(new KeyValPair<String, String>(incomingString, e.getMessage())); |
| } |
| logger.error("Failed to parse json tuple {}, Exception = {} ", tuple, e); |
| } |
| } |
| |
| @Override |
| public Object convert(byte[] tuple) |
| { |
| throw new UnsupportedOperationException("Not supported"); |
| } |
| |
| @Override |
| public KeyValPair<String, String> processErrorTuple(byte[] input) |
| { |
| throw new UnsupportedOperationException("Not supported"); |
| } |
| |
| /** |
| * Get jsonSchema contents as a string to be used during validation |
| * |
| * @return jsonSchema |
| */ |
| public String getJsonSchema() |
| { |
| return jsonSchema; |
| } |
| |
| /** |
| * Sets jsonSchema to be used during validation |
| * |
| * @param jsonSchema |
| * schema as a string |
| */ |
| public void setJsonSchema(String jsonSchema) |
| { |
| this.jsonSchema = jsonSchema; |
| } |
| |
| /** |
| * Get errorTupleCount |
| * |
| * @return errorTupleCount |
| */ |
| @VisibleForTesting |
| public long getErrorTupleCount() |
| { |
| return errorTupleCount; |
| } |
| |
| /** |
| * Get emittedObjectCount |
| * |
| * @return emittedObjectCount |
| */ |
| @VisibleForTesting |
| public long getEmittedObjectCount() |
| { |
| return emittedObjectCount; |
| } |
| |
| /** |
| * Get incomingTuplesCount |
| * |
| * @return incomingTuplesCount |
| */ |
| @VisibleForTesting |
| public long getIncomingTuplesCount() |
| { |
| return incomingTuplesCount; |
| } |
| |
| /** |
| * Set schema. |
| * |
| * @param schema |
| */ |
| @VisibleForTesting |
| public void setSchema(JsonSchema schema) |
| { |
| this.schema = schema; |
| } |
| |
| private static final Logger logger = LoggerFactory.getLogger(JsonParser.class); |
| } |