it.geosolutions.figis.requester.HTTPUtils.java Source code

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/*
 * ====================================================================
 *
 * Intersection Engine
 *
 * Copyright (C) 2007 - 2011 GeoSolutions S.A.S.
 * http://www.geo-solutions.it
 *
 * GPLv3 + Classpath exception
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.
 *
 * ====================================================================
 *
 * This software consists of voluntary contributions made by developers
 * of GeoSolutions.  For more information on GeoSolutions, please see
 * <http://www.geo-solutions.it/>.
 *
 */
package it.geosolutions.figis.requester;

import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;
import java.net.ConnectException;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import org.apache.commons.httpclient.Credentials;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.UsernamePasswordCredentials;
import org.apache.commons.httpclient.auth.AuthScope;
import org.apache.commons.httpclient.methods.DeleteMethod;
import org.apache.commons.httpclient.methods.EntityEnclosingMethod;
import org.apache.commons.httpclient.methods.FileRequestEntity;
import org.apache.commons.httpclient.methods.GetMethod;
import org.apache.commons.httpclient.methods.PostMethod;
import org.apache.commons.httpclient.methods.PutMethod;
import org.apache.commons.httpclient.methods.RequestEntity;
import org.apache.commons.httpclient.methods.StringRequestEntity;
import org.apache.commons.io.IOUtils;
import org.apache.log4j.Level;
import org.apache.log4j.Logger;

/**
* Low level HTTP utilities.
*/
class HTTPUtils {
    private static final Logger LOGGER = Logger.getLogger(HTTPUtils.class);

    /**
    * Performs an HTTP GET on the given URL.
    *
    * @param url The URL where to connect to.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    */
    public static String get(String url) throws MalformedURLException {
        return get(url, null, null);
    }

    /**
    * Performs an HTTP GET on the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    */
    public static String get(String url, String username, String pw) throws MalformedURLException {
        GetMethod httpMethod = null;
        try {
            HttpClient client = new HttpClient();
            setAuth(client, url, username, pw);
            httpMethod = new GetMethod(url);
            client.getHttpConnectionManager().getParams().setConnectionTimeout(5000);

            int status = client.executeMethod(httpMethod);
            if (status == HttpStatus.SC_OK) {
                InputStream is = httpMethod.getResponseBodyAsStream();
                String response = IOUtils.toString(is);
                if (response.trim().length() == 0) // sometime gs rest fails
                {
                    LOGGER.warn("ResponseBody is empty");

                    return null;
                } else {
                    return response;
                }
            } else {
                LOGGER.info("(" + status + ") " + HttpStatus.getStatusText(status) + " -- " + url);
            }
        } catch (ConnectException e) {
            LOGGER.error("Couldn't connect to [" + url + "]", e);
        } catch (IOException e) {
            LOGGER.error("Error talking to [" + url + "]", e);
        } finally {
            if (httpMethod != null) {
                httpMethod.releaseConnection();
            }
        }

        return null;
    }

    /**
    * PUTs a File to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param file The File to be sent.
    * @param contentType The content-type to advert in the PUT.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String put(String url, File file, String contentType, String username, String pw) {
        return put(url, new FileRequestEntity(file, contentType), username, pw);
    }

    /**
    * PUTs a String to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param content The content to be sent as a String.
    * @param contentType The content-type to advert in the PUT.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String put(String url, String content, String contentType, String username, String pw) {
        try {
            return put(url, new StringRequestEntity(content, contentType, null), username, pw);
        } catch (UnsupportedEncodingException ex) {
            LOGGER.error("Cannot PUT " + url, ex);

            return null;
        }
    }

    /**
    * PUTs a String representing an XML document to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param content The XML content to be sent as a String.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String putXml(String url, String content, String username, String pw) {
        return put(url, content, "text/xml", username, pw);
    }

    /**
    * Performs a PUT to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param requestEntity The request to be sent.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String put(String url, RequestEntity requestEntity, String username, String pw) {
        return send(new PutMethod(url), url, requestEntity, username, pw);
    }

    /**
    * POSTs a File to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param file The File to be sent.
    * @param contentType The content-type to advert in the POST.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String post(String url, File file, String contentType, String username, String pw) {
        return post(url, new FileRequestEntity(file, contentType), username, pw);
    }

    /**
    * POSTs a String to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param content The content to be sent as a String.
    * @param contentType The content-type to advert in the POST.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String post(String url, String content, String contentType, String username, String pw) {
        try {
            return post(url, new StringRequestEntity(content, contentType, null), username, pw);
        } catch (UnsupportedEncodingException ex) {
            LOGGER.error("Cannot POST " + url, ex);

            return null;
        }
    }

    /**
    * POSTs a String representing an XML document to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param content The XML content to be sent as a String.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String postXml(String url, String content, String username, String pw) {
        return post(url, content, "text/xml", username, pw);
    }

    /**
    * Performs a POST to the given URL.
    * <BR>Basic auth is used if both username and pw are not null.
    *
    * @param url The URL where to connect to.
    * @param requestEntity The request to be sent.
    * @param username Basic auth credential. No basic auth if null.
    * @param pw Basic auth credential. No basic auth if null.
    * @return The HTTP response as a String if the HTTP response code was 200 (OK).
    * @throws MalformedURLException
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    public static String post(String url, RequestEntity requestEntity, String username, String pw) {
        return send(new PostMethod(url), url, requestEntity, username, pw);
    }

    /**
    * Send an HTTP request (PUT or POST) to a server.
    * <BR>Basic auth is used if both username and pw are not null.
    * <P>
    * Only <UL>
    * <LI>200: OK</LI>
    * <LI>201: ACCEPTED</LI>
    * <LI>202: CREATED</LI>
    * </UL> are accepted as successful codes; in these cases the response string will be returned.
    *
    * @return the HTTP response or <TT>null</TT> on errors.
    */
    private static String send(final EntityEnclosingMethod httpMethod, String url, RequestEntity requestEntity,
            String username, String pw) {

        try {
            HttpClient client = new HttpClient();
            setAuth(client, url, username, pw);
            client.getHttpConnectionManager().getParams().setConnectionTimeout(5000);
            if (requestEntity != null) {
                httpMethod.setRequestEntity(requestEntity);
            }

            int status = client.executeMethod(httpMethod);

            switch (status) {
            case HttpURLConnection.HTTP_OK:
            case HttpURLConnection.HTTP_CREATED:
            case HttpURLConnection.HTTP_ACCEPTED:

                String response = IOUtils.toString(httpMethod.getResponseBodyAsStream());
                if (LOGGER.isInfoEnabled()) {
                    LOGGER.info("HTTP " + httpMethod.getStatusText() + ": " + response);
                }
                return response;
            default:
                LOGGER.warn("Bad response: code[" + status + "]" + " msg[" + httpMethod.getStatusText() + "]"
                        + " url[" + url + "]" + " method[" + httpMethod.getClass().getSimpleName() + "]: "
                        + IOUtils.toString(httpMethod.getResponseBodyAsStream()));

                return null;
            }
        } catch (ConnectException e) {
            LOGGER.error("Couldn't connect to [" + url + "]", e);

            return null;
        } catch (IOException e) {
            LOGGER.error("Error talking to " + url + " : " + e.getLocalizedMessage(), e);

            return null;
        } finally {
            if (httpMethod != null) {
                httpMethod.releaseConnection();
            }
        }
    }

    public static boolean delete(String url, final String user, final String pw) {

        DeleteMethod httpMethod = null;

        try {
            HttpClient client = new HttpClient();
            setAuth(client, url, user, pw);
            httpMethod = new DeleteMethod(url);
            client.getHttpConnectionManager().getParams().setConnectionTimeout(5000);

            int status = client.executeMethod(httpMethod);
            String response = "";
            if (status == HttpStatus.SC_OK) {
                InputStream is = httpMethod.getResponseBodyAsStream();
                response = IOUtils.toString(is);
                if (response.trim().equals("")) // sometimes gs rest fails
                {
                    if (LOGGER.isDebugEnabled()) {
                        LOGGER.debug(
                                "ResponseBody is empty (this may be not an error since we just performed a DELETE call)");
                    }

                    return true;
                }
                if (LOGGER.isDebugEnabled()) {
                    LOGGER.debug("(" + status + ") " + httpMethod.getStatusText() + " -- " + url);
                }

                return true;
            } else {
                if (LOGGER.isInfoEnabled()) {
                    LOGGER.info("(" + status + ") " + httpMethod.getStatusText() + " -- " + url);
                    LOGGER.info("Response: '" + response + "'");
                }
            }
        } catch (ConnectException e) {
            LOGGER.info("Couldn't connect to [" + url + "]", e);
        } catch (IOException e) {
            LOGGER.info("Error talking to [" + url + "]", e);
        } finally {
            if (httpMethod != null) {
                httpMethod.releaseConnection();
            }
        }

        return false;
    }

    /**
    * @return true if the server response was an HTTP_OK
    */
    public static boolean httpPing(String url) {
        return httpPing(url, null, null);
    }

    public static boolean httpPing(String url, String username, String pw) {

        GetMethod httpMethod = null;

        try {
            HttpClient client = new HttpClient();
            setAuth(client, url, username, pw);
            httpMethod = new GetMethod(url);
            client.getHttpConnectionManager().getParams().setConnectionTimeout(2000);

            int status = client.executeMethod(httpMethod);
            if (status != HttpStatus.SC_OK) {
                LOGGER.warn("PING failed at '" + url + "': (" + status + ") " + httpMethod.getStatusText());

                return false;
            } else {
                return true;
            }

        } catch (ConnectException e) {
            if (LOGGER.isInfoEnabled()) {
                LOGGER.log(Level.INFO, e.getLocalizedMessage(), e);
            }
            return false;
        } catch (IOException e) {
            if (LOGGER.isInfoEnabled()) {
                LOGGER.log(Level.INFO, e.getLocalizedMessage(), e);
            }
            return false;
        } finally {
            if (httpMethod != null) {
                httpMethod.releaseConnection();
            }
        }
    }

    /**
    * Used to query for REST resources.
    *
    * @param url The URL of the REST resource to query about.
    * @param username
    * @param pw
    * @return true on 200, false on 404.
    * @throws RuntimeException on unhandled status or exceptions.
    */
    public static boolean exists(String url, String username, String pw) {

        GetMethod httpMethod = null;

        try {
            HttpClient client = new HttpClient();
            setAuth(client, url, username, pw);
            httpMethod = new GetMethod(url);
            client.getHttpConnectionManager().getParams().setConnectionTimeout(2000);

            int status = client.executeMethod(httpMethod);
            switch (status) {
            case HttpStatus.SC_OK:
                return true;
            case HttpStatus.SC_NOT_FOUND:
                return false;
            default:
                throw new RuntimeException("Unhandled response status at '" + url + "': (" + status + ") "
                        + httpMethod.getStatusText());
            }
        } catch (ConnectException e) {
            throw new RuntimeException(e);
        } catch (IOException e) {
            throw new RuntimeException(e);
        } finally {
            if (httpMethod != null) {
                httpMethod.releaseConnection();
            }
        }
    }

    private static void setAuth(HttpClient client, String url, String username, String pw)
            throws MalformedURLException {
        URL u = new URL(url);
        if ((username != null) && (pw != null)) {
            Credentials defaultcreds = new UsernamePasswordCredentials(username, pw);
            client.getState().setCredentials(new AuthScope(u.getHost(), u.getPort()), defaultcreds);
            client.getParams().setAuthenticationPreemptive(true); // GS2 by default always requires authentication
        } else {
            if (LOGGER.isDebugEnabled()) {
                LOGGER.debug("Not setting credentials to access to " + url);
            }
        }
    }

}