org.trustedanalytics.h2oscoringengine.publisher.steps.AppBitsUploadingStep.java Source code

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Here is the source code for org.trustedanalytics.h2oscoringengine.publisher.steps.AppBitsUploadingStep.java

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/**
 * Copyright (c) 2015 Intel Corporation
 *
 * 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.
 */
package org.trustedanalytics.h2oscoringengine.publisher.steps;

import static org.trustedanalytics.h2oscoringengine.publisher.http.CloudFoundryEndpoints.APP_BITS_ENDPOINT_TEMPLATE;

import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.http.HttpEntity;
import org.springframework.http.HttpHeaders;
import org.springframework.http.HttpMethod;
import org.springframework.http.MediaType;
import org.springframework.http.converter.FormHttpMessageConverter;
import org.springframework.http.converter.HttpMessageConverter;
import org.springframework.http.converter.ResourceHttpMessageConverter;
import org.springframework.http.converter.json.MappingJackson2HttpMessageConverter;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;
import org.springframework.web.client.RestTemplate;
import org.trustedanalytics.h2oscoringengine.publisher.EnginePublicationException;
import org.trustedanalytics.h2oscoringengine.publisher.http.HttpCommunication;

public class AppBitsUploadingStep {

    private static final Logger LOGGER = LoggerFactory.getLogger(AppBitsUploadingStep.class);

    private final String cfApiUrl;
    private final RestTemplate cfRestTemplate;
    private final String appGuid;

    public AppBitsUploadingStep(String cfApiUrl, RestTemplate cfRestTemplate, String appGuid) {
        this.cfApiUrl = cfApiUrl;
        this.cfRestTemplate = cfRestTemplate;
        this.appGuid = appGuid;
    }

    public RegisteringInApplicationBrokerStep uploadBits(Path appBits) throws EnginePublicationException {
        prepareRestTemplateForMultipartRequest();
        LOGGER.info("Uploading bits for app " + appGuid + " from " + appBits);

        try {

            HttpEntity<MultiValueMap<String, Object>> request = prepareMutlipartRequest(appBits);

            String cfUploadAppUrl = cfApiUrl + APP_BITS_ENDPOINT_TEMPLATE;
            cfRestTemplate.exchange(cfUploadAppUrl, HttpMethod.PUT, request, String.class, appGuid);

            return new RegisteringInApplicationBrokerStep(appGuid, cfApiUrl, cfRestTemplate);
        } catch (IOException e) {
            throw new EnginePublicationException("Unable to read application bits from " + appBits.toString(), e);
        }
    }

    private void prepareRestTemplateForMultipartRequest() {
        List<HttpMessageConverter<?>> converters = new ArrayList<>(
                Arrays.asList(new MappingJackson2HttpMessageConverter(), new ResourceHttpMessageConverter(),
                        new FormHttpMessageConverter()));
        cfRestTemplate.getMessageConverters().addAll(converters);
    }

    /**
     * Prepares request to CF
     * <a href="https://apidocs.cloudfoundry.org/225/apps/uploads_the_bits_for_an_app.html">endpoint
     * </a>
     * 
     * @param dataPath
     * @return prepared request
     * @throws IOException
     */
    private HttpEntity<MultiValueMap<String, Object>> prepareMutlipartRequest(Path dataPath) throws IOException {
        HttpEntity<String> resourcesPart = prepareResourcesRequestPart();
        HttpEntity<ByteArrayResource> dataPart = prepareDataRequestPart(dataPath);

        MultiValueMap<String, Object> multiPartRequest = new LinkedMultiValueMap<>();
        multiPartRequest.add("resources", resourcesPart);
        multiPartRequest.add("application", dataPart);

        HttpHeaders headers = new HttpHeaders();
        headers.setContentType(MediaType.MULTIPART_FORM_DATA);

        return new HttpEntity<>(multiPartRequest, headers);

    }

    /**
     * CloudFoundry API requires an array of files it already has in cache.
     * We're sending an empty array here. 
     * 
     * @return
     */
    private HttpEntity<String> prepareResourcesRequestPart() {
        String resourcesJson = "[]";
        return new HttpEntity<>(resourcesJson);
    }

    private HttpEntity<ByteArrayResource> prepareDataRequestPart(Path dataPath) throws IOException {

        ByteArrayResource data = prepareData(dataPath);
        HttpHeaders headers = HttpCommunication.zipHeaders();

        return new HttpEntity<>(data, headers);
    }

    private ByteArrayResource prepareData(Path dataPath) throws IOException {
        return new ByteArrayResource(Files.readAllBytes(dataPath)) {
            @Override
            public String getFilename() {
                return dataPath.getFileName().toString();
            }
        };
    }
}