ru.parallel.octotron.http.requests.HttpExchangeWrapper.java Source code

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Here is the source code for ru.parallel.octotron.http.requests.HttpExchangeWrapper.java

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/*******************************************************************************
 * Copyright (c) 2014 SRCC MSU
 *
 * Distributed under the MIT License - see the accompanying file LICENSE.txt.
 ******************************************************************************/

package ru.parallel.octotron.http.requests;

import com.sun.net.httpserver.Headers;
import com.sun.net.httpserver.HttpExchange;
import org.apache.commons.io.IOUtils;
import ru.parallel.utils.format.ErrorString;
import ru.parallel.utils.format.TypedString;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.util.logging.Level;
import java.util.logging.Logger;

/**
 * stores all request information and<br>
 * allows to finish them with certain results<br>
 * */
public class HttpExchangeWrapper {
    private final static Logger LOGGER = Logger.getLogger("octotron");

    private final HttpExchange http_request;
    private final OutputStream http_request_writer;

    private boolean finished = false;

    private final String query;
    private final String path;

    public HttpExchangeWrapper(HttpExchange http_request) {
        this.http_request = http_request;
        http_request_writer = http_request.getResponseBody();

        query = http_request.getRequestURI().getQuery();
        path = http_request.getRequestURI().getPath();
    }

    /**
     * finish the current request, fill content_type and<br>
     * return code with data from result<br>
     * */
    public void Finish(TypedString result) throws IOException {
        int return_code;

        if (result instanceof ErrorString)
            return_code = HttpURLConnection.HTTP_BAD_REQUEST;
        else
            return_code = HttpURLConnection.HTTP_OK;

        Finish(result.string, result.GetContentType(), return_code);
    }

    /**
     * successfully finish request with specified response<br>
     * */
    public void FinishString(String response) throws IOException {
        Finish(response, "text/plain", HttpURLConnection.HTTP_OK);
    }

    /**
     * finish the current request with error and show the error description<br>
     * */
    public void FinishError(String description) throws IOException {
        Finish(description, "text/plain", HttpURLConnection.HTTP_BAD_REQUEST);
    }

    /**
     * finish the current request with specified content type and return code<br>
     * */
    private void Finish(String data, String content_type, int return_code) throws IOException {
        if (finished)
            throw new IOException("attempt to finish a finished request");

        finished = true;

        InputStream http_request_reader = http_request.getRequestBody();

        // read all body if the request has send something useless
        try {
            IOUtils.readLines(http_request_reader);
        } catch (IOException e) {
            LOGGER.log(Level.WARNING, "could not read from a request", e);
        } finally {
            try {
                http_request_reader.close();
            } catch (IOException e) {
                LOGGER.log(Level.WARNING, "could not read close a request", e);
            }
        }

        Headers header = http_request.getResponseHeaders();
        header.set("Content-Type", content_type + "; charset=us-ascii");

        // send headers and data
        try {
            byte[] raw_data = data.getBytes();
            http_request.sendResponseHeaders(return_code, raw_data.length);
            http_request_writer.write(raw_data);
        } catch (IOException e) // most likely a client closed without reading
        {
            LOGGER.log(Level.WARNING, "could not write all data", e);
        } finally {
            try {
                http_request_writer.close();
            } catch (IOException e) // may fail to close because did not write enough bytes
            {
                LOGGER.log(Level.WARNING, "could not close a writer", e);
            }
        }

        http_request.close();
    }

    public String GetQuery() {
        if (query == null)
            return "";
        return query;
    }

    public String GetPath() {
        if (path == null)
            return "";
        return path;
    }
}