ai.nitro.bot4j.integration.facebook.receive.webhook.impl.FacebookWebhookImpl.java Source code

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Here is the source code for ai.nitro.bot4j.integration.facebook.receive.webhook.impl.FacebookWebhookImpl.java

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/*
 * Copyright (C) 2016, nitro.ai
 * All rights reserved.
 *
 * This software may be modified and distributed under the terms
 * of the BSD 3-clause license. See the LICENSE file for details.
 */

package ai.nitro.bot4j.integration.facebook.receive.webhook.impl;

import java.io.IOException;

import javax.inject.Inject;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.apache.logging.log4j.util.Strings;

import com.google.common.io.CharStreams;
import com.restfb.DefaultJsonMapper;
import com.restfb.types.webhook.WebhookEntry;
import com.restfb.types.webhook.WebhookObject;
import com.restfb.types.webhook.messaging.MessagingItem;
import com.restfb.types.webhook.messaging.MessagingParticipant;

import ai.nitro.bot4j.integration.facebook.receive.FacebookReceiveHandler;
import ai.nitro.bot4j.integration.facebook.receive.webhook.FacebookWebhook;

public class FacebookWebhookImpl implements FacebookWebhook {

    private final static Logger LOG = LogManager.getLogger(FacebookWebhookImpl.class);

    @Inject
    protected FacebookReceiveHandler facebookMessageHandler;

    @Override
    public String get(final HttpServletRequest req, final HttpServletResponse res) {
        String result = "";

        try {
            result = handleChallenge(req);
        } catch (final Exception e) {
            handleException(e);
        }

        return result;
    }

    protected String handleChallenge(final HttpServletRequest req) throws IOException {
        final String hubMode = req.getParameter("hub.mode");
        final String hubChallenge = req.getParameter("hub.challenge");
        final String result;

        if (isGetModeSubscribe(hubMode, hubChallenge)) {
            result = hubChallenge;
        } else {
            result = "";
        }

        return result;
    }

    protected void handleException(final Exception e) {
        LOG.error(e.getMessage(), e);
    }

    protected void handleMessagingItem(final MessagingItem messagingItem, Long botId) {
        final MessagingParticipant sender = messagingItem.getSender();

        if (sender == null || Strings.isBlank(sender.getId())) {
            LOG.warn("Ignoring message with empty sender");
        } else {
            facebookMessageHandler.handleMessagingItem(messagingItem, botId);
        }
    }

    protected void handleWebhookEntry(final WebhookEntry webhookEntry, Long botId) {
        for (final MessagingItem messagingItem : webhookEntry.getMessaging()) {
            if (messagingItem != null) {
                handleMessagingItem(messagingItem, botId);
            }
        }
    }

    protected boolean isGetModeSubscribe(final String hubMode, final String hubChallenge) {
        return Strings.isNotBlank(hubMode) && Strings.isNotBlank(hubChallenge) && hubMode.equals("subscribe");
    }

    @Override
    public String post(final HttpServletRequest req, final HttpServletResponse res) {
        final String result = "";

        Long botId = Long.parseLong(req.getParameter("bot_id"));

        try {
            final String body = CharStreams.toString(req.getReader());
            final DefaultJsonMapper mapper = new DefaultJsonMapper();
            final WebhookObject webhookObject = mapper.toJavaObject(body, WebhookObject.class);

            for (final WebhookEntry webhookEntry : webhookObject.getEntryList()) {
                handleWebhookEntry(webhookEntry, botId);
            }
        } catch (final Exception e) {
            handleException(e);
        }

        return result;
    }
}