it.reply.orchestrator.resource.DeploymentResourceAssembler.java Source code

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Here is the source code for it.reply.orchestrator.resource.DeploymentResourceAssembler.java

Source

package it.reply.orchestrator.resource;

/*
 * Copyright  2015-2017 Santer Reply S.p.A.
 *
 * 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.
 */
import it.reply.orchestrator.controller.DeploymentController;
import it.reply.orchestrator.dal.entity.Deployment;
import it.reply.orchestrator.service.utils.MyLinkBuilder;

import org.springframework.hateoas.mvc.ControllerLinkBuilder;
import org.springframework.hateoas.mvc.ResourceAssemblerSupport;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestAttributes;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

import java.net.URI;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.locks.StampedLock;

import javax.servlet.http.HttpServletRequest;

@Component
public class DeploymentResourceAssembler extends ResourceAssemblerSupport<Deployment, DeploymentResource> {

    private URI uri;

    StampedLock lock = new StampedLock();

    public DeploymentResourceAssembler() {
        super(DeploymentController.class, DeploymentResource.class);
    }

    @Override
    public DeploymentResource toResource(Deployment entity) {
        return getDeploymentResource(entity);
    }

    private DeploymentResource getDeploymentResource(Deployment entity) {

        DeploymentResource resource = new DeploymentResource();
        resource.setUuid(entity.getId());
        resource.setCreationTime(entity.getCreated());
        resource.setUpdateTime(entity.getUpdated());
        resource.setStatus(entity.getStatus());
        resource.setStatusReason(entity.getStatusReason());
        resource.setCloudProviderName(entity.getCloudProviderName());

        resource.setTask(entity.getTask());

        resource.setOutputs(entity.getOutputs());

        if (entity.getCallback() != null) {
            resource.setCallback(entity.getCallback());
        }

        // TODO Use ControllerLinkBuilder when
        // https://github.com/spring-projects/spring-hateoas/issues/408 will be resolved
        URI ctrlUri = null;
        if (isInHttpRequest()) {
            ctrlUri = ControllerLinkBuilder.linkTo(DeploymentController.class).toUri();
            if (uri == null) {
                long writeStamp = lock.tryWriteLock();
                if (writeStamp != 0) {
                    uri = ctrlUri;
                    lock.unlockWrite(writeStamp);
                }
            }
        } else {
            if (uri != null || lock.isWriteLocked()) {
                try {
                    long readStamp = lock.tryReadLock(30, TimeUnit.SECONDS);
                    if (readStamp != 0) {
                        ctrlUri = uri;
                        lock.unlockRead(readStamp);
                    }
                } catch (InterruptedException ex) {
                    // DO NOTHING
                }
            }
        }
        if (ctrlUri == null) {
            ctrlUri = URI.create("");
        }

        resource.add(MyLinkBuilder.getNewBuilder(ctrlUri).slash("deployments").slash(entity).withSelfRel());
        resource.add(MyLinkBuilder.getNewBuilder(ctrlUri).slash("deployments").slash(entity).slash("resources")
                .withRel("resources"));
        resource.add(MyLinkBuilder.getNewBuilder(ctrlUri).slash("deployments").slash(entity).slash("template")
                .withRel("template"));
        /////////////////////////////////////////////////////////////////////////////////
        return resource;
    }

    // Dirty hack due to Spring Hateoas being unable to generate links outside of HTTP sessions
    // https://github.com/spring-projects/spring-hateoas/issues/408
    private boolean isInHttpRequest() {
        RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
        if (requestAttributes != null && requestAttributes instanceof ServletRequestAttributes) {
            HttpServletRequest servletRequest = ((ServletRequestAttributes) requestAttributes).getRequest();
            return servletRequest != null;
        }
        return false;
    }

}