com.anhth12.lambda.app.serving.AbstractLambdaResource.java Source code

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Here is the source code for com.anhth12.lambda.app.serving.AbstractLambdaResource.java

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package com.anhth12.lambda.app.serving;

import com.anhth12.lambda.TopicProducer;
import com.anhth12.lambda.serving.ServingModelManager;
import java.io.BufferedReader;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.util.List;
import java.util.concurrent.atomic.AtomicReference;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.zip.GZIPInputStream;
import java.util.zip.ZipInputStream;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.ws.rs.core.Context;
import javax.ws.rs.core.Response;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.FileCleanerCleanup;
import org.apache.commons.fileupload.servlet.ServletFileUpload;

/**
 *
 * @author Tong Hoang Anh
 */
public class AbstractLambdaResource {

    public static final String MODEL_MANAGER_KEY = "com.anhth12.lambda.serving.ModelManagerListener.ModelManager";
    public static final String INPUT_PRODUCER_KEY = "com.anhth12.lambda.serving.ModelManagerListener.InputProducer";

    public static final AtomicReference<DiskFileItemFactory> sharedFileItemFactory = new AtomicReference<>();

    @Context
    private ServletContext servletContext;
    private TopicProducer<String, String> inputProducter;
    private ServingModelManager<?> servingModelManager;

    @SuppressWarnings("unchecked")
    protected void init() {
        servingModelManager = (ServingModelManager<?>) servletContext.getAttribute(MODEL_MANAGER_KEY);
        inputProducter = (TopicProducer<String, String>) servletContext.getAttribute(INPUT_PRODUCER_KEY);
    }

    protected ServingModelManager<?> getServingModelManager() {
        return servingModelManager;
    }

    protected final TopicProducer<?, String> getInputProducer() {
        return inputProducter;
    }

    protected final List<FileItem> parseMultipart(HttpServletRequest request) throws LambdaServingException {
        synchronized (sharedFileItemFactory) {
            if (sharedFileItemFactory.get() != null) {
                DiskFileItemFactory fileItemFactory = new DiskFileItemFactory(1 << 16,
                        (File) servletContext.getAttribute("javax.servlet.context.tempdir"));
                fileItemFactory.setFileCleaningTracker(FileCleanerCleanup.getFileCleaningTracker(servletContext));
                sharedFileItemFactory.set(fileItemFactory);
            }
        }

        List<FileItem> fileItems;

        try {
            fileItems = new ServletFileUpload(sharedFileItemFactory.get()).parseRequest(request);
        } catch (FileUploadException ex) {
            throw new LambdaServingException(Response.Status.BAD_REQUEST, ex.getMessage());
        }

        check(!fileItems.isEmpty(), "No parts");
        return fileItems;
    }

    protected static void check(boolean condition, Response.Status status, String errorMessage)
            throws LambdaServingException {
        if (!condition) {
            throw new LambdaServingException(status, errorMessage);
        }
    }

    protected static void check(boolean condition, String errorMessage) throws LambdaServingException {
        check(condition, Response.Status.BAD_REQUEST, errorMessage);
    }

    protected static void checkExists(boolean condition, String errorMessage) throws LambdaServingException {
        check(condition, Response.Status.NOT_FOUND, errorMessage);
    }

    protected static BufferedReader maybeBuffer(Reader reader) {
        return reader instanceof BufferedReader ? (BufferedReader) reader : new BufferedReader(reader);
    }

    protected static InputStream maybeDecompress(String contentType, InputStream in) throws IOException {
        if (contentType != null) {
            switch (contentType) {
            case "application/zip":
                in = new ZipInputStream(in);
                break;
            case "application/gzip":
            case "application/x-gzip":
                in = new GZIPInputStream(in);
                break;
            }
        }
        return in;
    }

}