path: root/sdnr/wt/data-provider/provider/src/main/java/org/onap/ccsdk/features/sdnr/wt/dataprovider/database/EsDataObjectReaderWriter.java

/*
 * ============LICENSE_START=======================================================
 * ONAP : ccsdk features
 * ================================================================================
 * Copyright (C) 2019 highstreet technologies GmbH Intellectual Property.
 * All rights reserved.
 * ================================================================================
 * Licensed 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.
 * ============LICENSE_END=========================================================
 *
 */
package org.onap.ccsdk.features.sdnr.wt.dataprovider.database;

import java.io.IOException;
import java.lang.reflect.Field;
import java.util.List;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import org.onap.ccsdk.features.sdnr.wt.common.database.DatabaseClient;
import org.onap.ccsdk.features.sdnr.wt.common.database.SearchHit;
import org.onap.ccsdk.features.sdnr.wt.common.database.SearchResult;
import org.onap.ccsdk.features.sdnr.wt.common.database.queries.QueryBuilder;
import org.onap.ccsdk.features.sdnr.wt.dataprovider.yangtools.YangToolsMapper;
import org.opendaylight.yang.gen.v1.urn.opendaylight.params.xml.ns.yang.data.provider.rev190801.Entity;
import org.opendaylight.yangtools.concepts.Builder;
import org.opendaylight.yangtools.yang.binding.DataObject;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.fasterxml.jackson.core.JsonProcessingException;

/**
 * Class to rw yang-tool generated objects into elasticsearch database. For "ES _id" exchange the esIdAddAtributteName is used.
 * This attribute mast be of type String and contains for read and write operations the object id.
 * The function can be used without id handling.
 * If id handling is required the parameter needs to be specified by class definition in yang and  setting the name by using setAttributeName()
 *
 * @param <T> Yang tools generated class object.
 */
public class EsDataObjectReaderWriter<T extends DataObject> {

 	private final Logger LOG = LoggerFactory.getLogger(EsDataObjectReaderWriter.class);

 	/** Typename for elastic search data schema **/
	private String dataTypeName;

	/** Elasticsearch Database client to be used **/
	private DatabaseClient db;

	/** Mapper with configuration to use opendaylight yang-tools builder pattern for object creation **/
	private YangToolsMapper yangtoolsMapper;

	/** Class of T as attribute to allow JSON to Class object mapping **/
	private Class<T> clazz;

	/** Field is used to write id. If null no id handling **/
	private @Nullable Field field;

	/** Attribute that is used as id field for the database object **/
	private @Nullable String esIdAddAtributteName;

	/** Interface to be used for write operations. Rule for write: T extends S and  **/
	private Class<? extends DataObject> writeInterfaceClazz; // == "S"

	/**
	 * Elasticsearch database read and write for specific class, defined by opendaylight yang-tools.
	 *
	 * @param db Database access client
	 * @param dataTypeName typename in database schema
	 * @param clazz class of type to be handled
	 * @throws ClassNotFoundException
	 */
	public EsDataObjectReaderWriter(DatabaseClient db, Entity dataTypeName, Class<T> clazz) throws ClassNotFoundException {
		this(db, dataTypeName.getName(), clazz);
	}
	public EsDataObjectReaderWriter(DatabaseClient db, String dataTypeName, Class<T> clazz) throws ClassNotFoundException {
		LOG.info("Create {} for datatype {} class {}", this.getClass().getName(), dataTypeName, clazz.getName());

		this.esIdAddAtributteName = null;
		this.field = null;
		this.writeInterfaceClazz = clazz;
		this.db = db;
		this.dataTypeName = dataTypeName;
		this.yangtoolsMapper = new YangToolsMapper();
		//this.yangtoolsMapper.assertBuilderClass(clazz);
		this.clazz = clazz;
//
//		if (! db.isExistsIndex(dataTypeName)) {
//			throw new IllegalArgumentException("Index "+dataTypeName+" not existing.");
//		}
	}

	public String getDataTypeName() {
		return dataTypeName;
	}
	public Class<T> getClazz() {
		return clazz;
	}
	/**
	 * Simlar to {@link #setEsIdAttributeName()}, but adapts the parameter to yangtools attribute naming schema
	 * @param esIdAttributeName is converted to UnderscoreCamelCase
	 * @return this for further operations.
	 */
	public EsDataObjectReaderWriter<T> setEsIdAttributeNameCamelized(String esIdAttributeName) {
		return setEsIdAttributeName(YangToolsMapper.toCamelCaseAttributeName(esIdAttributeName));
	}

	/**
	 * Attribute name of class that is containing the object id
	 * @param esIdAttributeName of the implementation class for the yangtools interface.
	 *        Expected attribute name format is CamelCase with leading underline. @
	 * @return this for further operations.
	 * @throws SecurityException if no access or IllegalArgumentException if wrong type or no attribute with this name.
	 */
	public EsDataObjectReaderWriter<T> setEsIdAttributeName(String esIdAttributeName) {
		LOG.debug("Set attribute '{}'", esIdAttributeName);
		this.esIdAddAtributteName = null; // Reset status
		this.field = null;

		Field attributeField;
		try {
			Builder<T> builder = yangtoolsMapper.getBuilder(clazz);
			T object = builder.build();
			attributeField = object.getClass().getDeclaredField(esIdAttributeName);
			if (attributeField.getType().equals(String.class)) {
				attributeField.setAccessible(true);
				this.esIdAddAtributteName = esIdAttributeName; //Set new status if everything OK
				this.field = attributeField;
			} else {
				String msg = "Wrong field type " + attributeField.getType().getName() + " of " + esIdAttributeName;
				LOG.debug(msg);
				throw new IllegalArgumentException(msg);
			}
		} catch (NoSuchFieldException e) {
			// Convert to run-time exception
			String msg = "NoSuchFieldException for '" + esIdAttributeName + "' in class " + clazz.getName();
			LOG.debug(msg);
			throw new IllegalArgumentException(msg);
		} catch (SecurityException e) {
			LOG.debug("Access problem "+esIdAttributeName,e);
			throw e;
		}
		return this;
	}

	/**
	 * Specify subclass of T for write operations.
	 * @param writeInterfaceClazz
	 */
	public EsDataObjectReaderWriter<T> setWriteInterface( @Nonnull Class<? extends DataObject> writeInterfaceClazz ) {
		LOG.debug("Set write interface to {}", writeInterfaceClazz);
		if (writeInterfaceClazz == null)
			throw new IllegalArgumentException("Null not allowed here.");

		this.writeInterfaceClazz = writeInterfaceClazz;
		return this;
	}

	/**
	 * Write child object to database with specific id
	 * @param object
	 * @param @Nullable esId use the id or if null generate unique id
	 * @return String with id or null
	 */
	public @Nullable <S extends DataObject> String write(S object, @Nullable String esId) {
		if (writeInterfaceClazz.isInstance(object)) {
			try {
				String json = yangtoolsMapper.writeValueAsString(object);
				return db.doWriteRaw(dataTypeName, esId, json);
			} catch (JsonProcessingException e) {
				LOG.error("Write problem: ", e);
			}
		} else {
			LOG.error("Type {} does not provide interface {}", object!=null?object.getClass().getName():"null",
					writeInterfaceClazz.getName());
		}
		return null;
	}
	/**
	 * Update partial child object to database with match/term query
	 * @param object
	 * @param esId
	 * @return String with esId or null
	 */
	public @Nullable <S extends DataObject> boolean update(S object, QueryBuilder query) {
		if (writeInterfaceClazz.isInstance(object)) {
			try {
				String json = yangtoolsMapper.writeValueAsString(object);
				return db.doUpdate(this.dataTypeName,json,query);
			} catch (JsonProcessingException e) {
				LOG.error("Update problem: ", e);
			}
		} else {
			LOG.error("Type {} does not provide interface {}", object!=null?object.getClass().getName():"null",
					writeInterfaceClazz.getName());
		}
		return false;
	}
	/**
	 * Write/ update partial child object to database with specific id Write if not
	 * exists, else update
	 * @param object
	 * @param esId
	 * @return String with esId or null
	 */
	public @Nullable <S extends DataObject> String update(S object, String esId) {
		return this.update(object, esId,null);
	}
	public @Nullable <S extends DataObject> String update(S object, String esId,List<String> onylForInsert) {
		if (writeInterfaceClazz.isInstance(object)) {
			try {
				String json = yangtoolsMapper.writeValueAsString(object);
				return db.doUpdateOrCreate(dataTypeName, esId, json,onylForInsert);
			} catch (JsonProcessingException e) {
				LOG.error("Update problem: ", e);
			}
		} else {
			LOG.error("Type {} does not provide interface {}", object!=null?object.getClass().getName():"null",
					writeInterfaceClazz.getName());
		}
		return null;
	}

    /**
     * Read object from database, by using the id field
     * @param object
     * @return
     */
    public @Nullable T read(String esId) {
    	@Nullable T res = (T)null;
		if (esId != null) {
			String json = db.doReadJsonData(dataTypeName, esId);
			try {
				res = yangtoolsMapper.readValue(json.getBytes(), clazz);
			} catch (IOException e) {
				LOG.error("Problem: ", e);
			}
		}
        return res;
    }

    /**
     * Remove object
     * @param esId to identify the object.
     * @return success
     */
    public boolean remove(String esId) {
    	return db.doRemove(this.dataTypeName, esId);
    }

	public int remove(QueryBuilder query) {
		return this.db.doRemove(this.dataTypeName, query);
	}
    /**
     * Get all elements of related type
     * @return all Elements
     */
    public SearchResult<T> doReadAll() {
        return doReadAll(null);
    }
    public SearchResult<T> doReadAll(QueryBuilder query) {
    	return this.doReadAll(query,false);
	}
    /**
     * Read all existing objects of a type
     * @param query for the elements
     * @return the list of all objects
     */

    public SearchResult<T> doReadAll(QueryBuilder query, boolean ignoreException) {

    	SearchResult<T> res = new SearchResult<T>();
        int idx = 0;                //Idx for getAll
        int iterateLength = 100;    //Step width for iterate

        SearchResult<SearchHit> result;
        List<SearchHit> hits;
        do {
            if(query!=null) {
                LOG.debug("read data in {} with query {}",dataTypeName,query.toJSON());
                result=db.doReadByQueryJsonData( dataTypeName, query,ignoreException);
            }
            else {
            	result = db.doReadAllJsonData(dataTypeName,ignoreException);
            }
            hits=result.getHits();
            LOG.debug("Read: {} elements: {}  Failures: {}",dataTypeName,hits.size(), yangtoolsMapper.getMappingFailures());

            T object;
            idx += result.getHits().size();
			for (SearchHit hit : hits) {
				object = getT(hit.getSourceAsString());
				LOG.debug("Mapp Object: {}\nSource: '{}'\nResult: '{}'\n Failures: {}", hit.getId(),
						hit.getSourceAsString(), object, yangtoolsMapper.getMappingFailures());
				if (object != null) {
					setEsId(object, hit.getId());
					res.add(object);
				} else {
					LOG.warn("Mapp result null Object: {}\n Source: '{}'\n : '", hit.getId(), hit.getSourceAsString());
				}
			}

		} while (hits.size() == iterateLength); // Do it until end indicated, because less hits than iterateLength
												// allows.
        res.setTotal(result.getTotal());
        return res;
    }

	/* ---------------------------------------------
     * Private functions
     */

	private void setEsId(T object, String esId) {
		if (field != null) {
			try {
				field.set(object, esId);
			} catch (IllegalArgumentException | IllegalAccessException e) {
				LOG.debug("Field set problem.", e);			}
		}
	}

    private @Nullable T getT(String jsonString) {
    	try {
			return yangtoolsMapper.readValue( jsonString, clazz );
		} catch (IOException e) {
			LOG.info("Mapping problem", e);
			return (T)null;
		}
    }

}