com.springsource.greenhouse.invite.FacebookInviteController.java Source code

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Here is the source code for com.springsource.greenhouse.invite.FacebookInviteController.java

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/*
 * Copyright 2010 the original author or authors.
 *
 * 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 com.springsource.greenhouse.invite;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

import javax.inject.Inject;

import org.springframework.beans.factory.annotation.Value;
import org.springframework.social.connect.UsersConnectionRepository;
import org.springframework.social.facebook.api.Facebook;
import org.springframework.social.facebook.api.Reference;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;

import com.springsource.greenhouse.account.Account;
import com.springsource.greenhouse.account.AccountRepository;
import com.springsource.greenhouse.account.ProfileReference;
import com.springsource.greenhouse.utils.Message;

/**
 * UI Controller for inviting Facebook friends to join our community.
 * @author Keith Donald
 */
@Controller
public class FacebookInviteController {

    private final Facebook facebook;

    private final UsersConnectionRepository connectionRepository;

    private final AccountRepository accountRepository;

    /**
     * Construct the FacebookInviteController.
     * The Facebook ServiceProvider is injected for obtaining the client-side proxy to Facebook's REST API.
     * It is also used to lookup which of a member's Facebook friends have already joined our community.
     */
    @Inject
    public FacebookInviteController(Facebook facebook, UsersConnectionRepository connectionRepository,
            AccountRepository accountRepository) {
        this.facebook = facebook;
        this.connectionRepository = connectionRepository;
        this.accountRepository = accountRepository;
    }

    /**
     * Renders the Facebook friend-finder page as HTML in the web browser.
     * If the member's account is connected to Facebook, adds his or her Facebook friends who are already members to the model.
     * Supports distinguishing between those Facebook friends who have already joined and those who haven't.
     */
    @RequestMapping(value = "/invite/facebook", method = RequestMethod.GET)
    public void friendFinder(Model model, Account account) {
        if (facebook.isAuthorized()) {
            List<ProfileReference> profileReferences = accountRepository
                    .findProfileReferencesByIds(friendAccountIds(account.getId(), facebook));
            model.addAttribute("friends", profileReferences);
        } else {
            model.addAttribute("friends", Collections.emptySet());
        }
        model.addAttribute("facebookAppId", facebookAppId);
    }

    /**
     * Called by the Facebook multi-friend-selector form after sending invitations.
     * Redirects the user back to the invite page and renders a success message.
     * @param inviteIds the invitation ids assigned by Facebook, one for each invitation sent
     */
    @RequestMapping(value = "/invite/facebook/request-form", method = RequestMethod.POST)
    public String invitationsSent(@RequestParam("ids[]") String[] inviteIds, RedirectAttributes redirectAttrs) {
        redirectAttrs.addFlashAttribute(Message.success("Your invitations have been sent"));
        return "redirect:/invite";
    }

    /**
     * Called by the Facebook multi-friend-selector form after choosing to cancel the sending of one or more invites.
     * Redirects the user back to the main invite page.
     */
    @RequestMapping(value = "/invite/facebook/request-form", method = RequestMethod.GET)
    public String invitationsCancelled() {
        return "redirect:/invite";
    }

    // internal helpers

    private List<Long> friendAccountIds(Long accountId, Facebook facebook) {
        List<Reference> friends = facebook.friendOperations().getFriends();
        if (friends.isEmpty()) {
            return Collections.emptyList();
        }
        Set<String> providerUserIds = new HashSet<String>(friends.size());
        for (Reference friend : friends) {
            providerUserIds.add(friend.getId());
        }
        Set<String> userIds = connectionRepository.findUserIdsConnectedTo("facebook", providerUserIds);
        List<Long> friendAccountIds = new ArrayList<Long>(userIds.size());
        for (String localUserId : userIds) {
            friendAccountIds.add(Long.valueOf(localUserId));
        }
        return friendAccountIds;
    }

    @Value("#{environment['facebook.appId']}")
    private String facebookAppId;

}