ResourceUpsert.java

package io.katharsis.dispatcher.controller.resource;

import com.fasterxml.jackson.databind.ObjectMapper;
import io.katharsis.dispatcher.controller.BaseController;
import io.katharsis.queryParams.QueryParams;
import io.katharsis.repository.RepositoryMethodParameterProvider;
import io.katharsis.request.dto.DataBody;
import io.katharsis.request.dto.LinkageData;
import io.katharsis.resource.exception.ResourceException;
import io.katharsis.resource.exception.ResourceNotFoundException;
import io.katharsis.resource.field.ResourceAttributesBridge;
import io.katharsis.resource.field.ResourceField;
import io.katharsis.resource.information.ResourceInformation;
import io.katharsis.resource.registry.RegistryEntry;
import io.katharsis.resource.registry.ResourceRegistry;
import io.katharsis.resource.registry.responseRepository.RelationshipRepositoryAdapter;
import io.katharsis.utils.Generics;
import io.katharsis.utils.PropertyUtils;
import io.katharsis.utils.parser.TypeParser;

import java.io.Serializable;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.Objects;

public abstract class ResourceUpsert extends BaseController {
    final ResourceRegistry resourceRegistry;
    final TypeParser typeParser;
    private final ObjectMapper objectMapper;

    public ResourceUpsert(ResourceRegistry resourceRegistry, TypeParser typeParser, ObjectMapper objectMapper) {
        this.resourceRegistry = resourceRegistry;
        this.typeParser = typeParser;
        this.objectMapper = objectMapper;
    }

    void setId(DataBody dataBody, Object instance, ResourceInformation resourceInformation) {
        if (dataBody.getId() != null) {
            String id = dataBody.getId();

            @SuppressWarnings("unchecked") Class<? extends Serializable> idClass = (Class<? extends Serializable>)
                resourceInformation
                    .getIdField()
                    .getType();
            Serializable castedId = typeParser.parse(id, idClass);
            PropertyUtils.setProperty(instance, resourceInformation.getIdField()
                .getUnderlyingName(), castedId);
        }
    }

    void setAttributes(DataBody dataBody, Object instance, ResourceInformation resourceInformation) {
        if (dataBody.getAttributes() != null) {
            ResourceAttributesBridge resourceAttributesBridge = resourceInformation.getAttributeFields();
            resourceAttributesBridge.setProperties(objectMapper, instance, dataBody.getAttributes());
        }
    }

    protected void saveRelations(QueryParams queryParams, Object savedResource, RegistryEntry registryEntry, DataBody dataBody,
                                 RepositoryMethodParameterProvider parameterProvider) {
        if (dataBody.getRelationships() != null) {
            Map<String, Object> additionalProperties = dataBody.getRelationships()
                .getAdditionalProperties();
            for (Map.Entry<String, Object> property : additionalProperties.entrySet()) {
                if (Iterable.class.isAssignableFrom(property.getValue()
                    .getClass())) {
                    //noinspection unchecked
                    saveRelationsField(queryParams, savedResource, registryEntry, (Map.Entry) property, registryEntry
                        .getResourceInformation(), parameterProvider);
                } else {
                    //noinspection unchecked
                    saveRelationField(queryParams, savedResource, registryEntry, (Map.Entry) property, registryEntry
                        .getResourceInformation(), parameterProvider);
                }

            }
        }
    }

    private void saveRelationsField(QueryParams queryParams, Object savedResource, RegistryEntry registryEntry,
                                    Map.Entry<String, Iterable<LinkageData>> property,
                                    ResourceInformation resourceInformation,
                                    RepositoryMethodParameterProvider parameterProvider) {
        if (!allTypesTheSame(property.getValue())) {
            throw new ResourceException("Not all types are the same for linkage: " + property.getKey());
        }

        String type = getLinkageType(property.getValue());
        RegistryEntry relationRegistryEntry = getRelationRegistryEntry(type);
        @SuppressWarnings("unchecked")
        Class<? extends Serializable> relationshipIdClass = (Class<? extends Serializable>) relationRegistryEntry
            .getResourceInformation()
            .getIdField()
            .getType();
        List<Serializable> castedRelationIds = new LinkedList<>();

        for (LinkageData linkageData : property.getValue()) {
            Serializable castedRelationshipId = typeParser.parse(linkageData.getId(), relationshipIdClass);
            castedRelationIds.add(castedRelationshipId);
        }

        Class<?> relationshipClass = relationRegistryEntry.getResourceInformation()
            .getResourceClass();
        RelationshipRepositoryAdapter relationshipRepository = registryEntry
            .getRelationshipRepositoryForClass(relationshipClass, parameterProvider);
        ResourceField relationshipField = resourceInformation.findRelationshipFieldByName(property.getKey());
        //noinspection unchecked
        relationshipRepository.setRelations(savedResource, castedRelationIds,
            relationshipField.getUnderlyingName(), queryParams);
    }

    private static boolean allTypesTheSame(Iterable<LinkageData> linkages) {
        String type = linkages.iterator()
            .hasNext() ? linkages.iterator()
            .next()
            .getType() : null;
        for (LinkageData linkageData : linkages) {
            if (!Objects.equals(type, linkageData.getType())) {
                return false;
            }
        }
        return true;
    }

    protected String getLinkageType(Iterable<LinkageData> linkages) {
        return linkages.iterator()
            .hasNext() ? linkages.iterator()
            .next()
            .getType() : null;
    }

    private void saveRelationField(QueryParams queryParams, Object savedResource, RegistryEntry registryEntry,
                                   Map.Entry<String, LinkageData> property, ResourceInformation resourceInformation,
                                   RepositoryMethodParameterProvider parameterProvider) {
        RegistryEntry relationRegistryEntry = getRelationRegistryEntry(property.getValue()
            .getType());

        @SuppressWarnings("unchecked")
        Class<? extends Serializable> relationshipIdClass = (Class<? extends Serializable>) relationRegistryEntry
            .getResourceInformation()
            .getIdField()
            .getType();
        Serializable castedRelationshipId = typeParser.parse(property.getValue()
            .getId(), relationshipIdClass);

        Class<?> relationshipClass = relationRegistryEntry.getResourceInformation()
            .getResourceClass();
        RelationshipRepositoryAdapter relationshipRepository = registryEntry
            .getRelationshipRepositoryForClass(relationshipClass, parameterProvider);
        ResourceField relationshipField = resourceInformation.findRelationshipFieldByName(property.getKey());
        //noinspection unchecked
        relationshipRepository.setRelation(savedResource, castedRelationshipId, relationshipField.getUnderlyingName(),
            queryParams);
    }

    private RegistryEntry getRelationRegistryEntry(String type) {
        RegistryEntry relationRegistryEntry = resourceRegistry.getEntry(type);
        if (relationRegistryEntry == null) {
            throw new ResourceNotFoundException(type);
        }
        return relationRegistryEntry;
    }

    Object buildNewResource(RegistryEntry registryEntry, DataBody dataBody, String resourceName) {
        if (dataBody == null) {
            throw new ResourceException("No data field in the body.");
        }
        if (!resourceName.equals(dataBody.getType())) {
            throw new ResourceException(String.format("Inconsistent type definition between path and body: body type: " +
                "%s, request type: %s", dataBody.getType(), resourceName));
        }
        try {
            return registryEntry.getResourceInformation()
                .getResourceClass()
                .newInstance();
        } catch (InstantiationException | IllegalAccessException e) {
            throw new ResourceException(
                String.format("couldn't create a new instance of %s", registryEntry.getResourceInformation()
                    .getResourceClass()));
        }
    }

    protected void setRelations(Object newResource, RegistryEntry registryEntry, DataBody dataBody, QueryParams
        queryParams,
                                RepositoryMethodParameterProvider parameterProvider) {
        if (dataBody.getRelationships() != null) {
            Map<String, Object> additionalProperties = dataBody.getRelationships()
                .getAdditionalProperties();
            for (Map.Entry<String, Object> property : additionalProperties.entrySet()) {
                if (property.getValue() != null && Iterable.class.isAssignableFrom(property.getValue()
                    .getClass())) {
                    //noinspection unchecked
                    setRelationsField(newResource, registryEntry, (Map.Entry) property, queryParams, parameterProvider);
                } else {
                    //noinspection unchecked
                    setRelationField(newResource, registryEntry, (Map.Entry) property, queryParams, parameterProvider);
                }

            }
        }
    }

    private void setRelationsField(Object newResource, RegistryEntry registryEntry,
                                   Map.Entry<String, Iterable<LinkageData>> property, QueryParams queryParams,
                                   RepositoryMethodParameterProvider parameterProvider) {
        String propertyName = property.getKey();
        ResourceField relationshipField = registryEntry.getResourceInformation()
            .findRelationshipFieldByName(propertyName);
        Class<?> relationshipFieldClass = Generics.getResourceClass(relationshipField.getGenericType(),
            relationshipField.getType());
        RegistryEntry entry = resourceRegistry.getEntry(relationshipFieldClass);
        Class idFieldType = entry.getResourceInformation()
            .getIdField()
            .getType();

        List relationships = new LinkedList<>();
        for (LinkageData linkageData : property.getValue()) {
            Serializable castedRelationshipId = typeParser.parse(linkageData.getId(), idFieldType);
            Object relationObject = entry.getResourceRepository(parameterProvider)
                .findOne(castedRelationshipId, queryParams)
                .getEntity();
            relationships.add(relationObject);
        }
        PropertyUtils.setProperty(newResource, relationshipField.getUnderlyingName(), relationships);
    }

    private void setRelationField(Object newResource, RegistryEntry registryEntry,
                                  Map.Entry<String, LinkageData> property, QueryParams queryParams,
                                  RepositoryMethodParameterProvider parameterProvider) {

        ResourceField relationshipFieldByName = registryEntry.getResourceInformation()
                .findRelationshipFieldByName(property.getKey());

        Object relationObject;
        if (property.getValue() != null) {
            RegistryEntry entry = resourceRegistry.getEntry(relationshipFieldByName.getType());
            Class idFieldType = entry.getResourceInformation()
                .getIdField()
                .getType();
            Serializable castedRelationshipId = typeParser.parse(property.getValue()
                .getId(), idFieldType);
            relationObject = entry.getResourceRepository(parameterProvider)
                .findOne(castedRelationshipId, queryParams)
            .getEntity();
        } else {
            relationObject = null;
        }

        PropertyUtils.setProperty(newResource, relationshipFieldByName.getUnderlyingName(), relationObject);
    }
}