package com.google.devrel.training.conference.spi;
import static com.google.devrel.training.conference.service.OfyService.factory;
import static com.google.devrel.training.conference.service.OfyService.ofy;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import javax.inject.Named;
import com.google.api.server.spi.config.Api;
import com.google.api.server.spi.config.ApiMethod;
import com.google.api.server.spi.config.ApiMethod.HttpMethod;
import com.google.api.server.spi.response.ConflictException;
import com.google.api.server.spi.response.ForbiddenException;
import com.google.api.server.spi.response.NotFoundException;
import com.google.api.server.spi.response.UnauthorizedException;
import com.google.appengine.api.memcache.MemcacheService;
import com.google.appengine.api.memcache.MemcacheServiceFactory;
import com.google.appengine.api.taskqueue.Queue;
import com.google.appengine.api.taskqueue.QueueFactory;
import com.google.appengine.api.taskqueue.TaskOptions;
import com.google.appengine.api.users.User;
import com.google.devrel.training.conference.Constants;
import com.google.devrel.training.conference.domain.Announcement;
import com.google.devrel.training.conference.domain.Conference;
import com.google.devrel.training.conference.domain.Profile;
import com.google.devrel.training.conference.form.ConferenceForm;
import com.google.devrel.training.conference.form.ConferenceQueryForm;
import com.google.devrel.training.conference.form.ProfileForm;
import com.google.devrel.training.conference.form.ProfileForm.TeeShirtSize;
import com.googlecode.objectify.Key;
import com.googlecode.objectify.Work;
import com.googlecode.objectify.cmd.Query;
/**
* Defines conference APIs.
*/
@Api(name = "conference", version = "v1",
scopes = { Constants.EMAIL_SCOPE }, clientIds = {
Constants.WEB_CLIENT_ID,
Constants.API_EXPLORER_CLIENT_ID },
description = "API for the Conference Central Backend application.")
public class ConferenceApi {
/*
* Get the display name from the user's email. For example, if the email is
* lemoncake@example.com, then the display name becomes "lemoncake."
*/
private static final Boolean True = null;
private static final Boolean False = null;
private static String extractDefaultDisplayNameFromEmail(String email) {
return email == null ? null : email.substring(0, email.indexOf("@"));
}
/**
* Creates or updates a Profile object associated with the given user
* object.
*
* @param user
* A User object injected by the cloud endpoints.
* @param profileForm
* A ProfileForm object sent from the client form.
* @return Profile object just created.
* @throws UnauthorizedException
* when the User object is null.
*/
// Declare this method as a method available externally through Endpoints
@ApiMethod(name = "saveProfile", path = "profile", httpMethod = HttpMethod.POST)
// The request that invokes this method should provide data that
// conforms to the fields defined in ProfileForm
// TODO 1 Pass the ProfileForm parameter
// TODO 2 Pass the User parameter
public Profile saveProfile(final User user, ProfileForm profileForm)
throws UnauthorizedException {
// TODO 2
// If the user is not logged in, throw an UnauthorizedException
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
// TODO 2
// Get the userId and mainEmail
String mainEmail = user.getEmail();
String userId = user.getUserId();
// TODO 1
// Get the displayName and teeShirtSize sent by the request.
String displayName = profileForm.getDisplayName();
TeeShirtSize teeShirtSize = profileForm.getTeeShirtSize();
// Get the Profile from the datastore if it exists
// otherwise create a new one
Profile profile = ofy().load().key(Key.create(Profile.class, userId))
.now();
if (profile == null) {
// Populate the displayName and teeShirtSize with default values
// if not sent in the request
if (displayName == null) {
displayName = extractDefaultDisplayNameFromEmail(user
.getEmail());
}
if (teeShirtSize == null) {
teeShirtSize = TeeShirtSize.NOT_SPECIFIED;
}
// Now create a new Profile entity
profile = new Profile(userId, displayName, mainEmail, teeShirtSize);
} else {
// The Profile entity already exists
// Update the Profile entity
profile.update(displayName, teeShirtSize);
}
// TODO 3
// Save the entity in the datastore
ofy().save().entity(profile).now();
// Return the profile
return profile;
}
/**
* Returns a Profile object associated with the given user object. The cloud
* endpoints system automatically inject the User object.
*
* @param user
* A User object injected by the cloud endpoints.
* @return Profile object.
* @throws UnauthorizedException
* when the User object is null.
*/
@ApiMethod(name = "getProfile", path = "profile", httpMethod = HttpMethod.GET)
public Profile getProfile(final User user) throws UnauthorizedException {
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
// TODO
// load the Profile Entity
String userId = user.getUserId();
Key key = Key.create(Profile.class, userId);
Profile profile = (Profile) ofy().load().key(key).now();
return profile;
}
/**
* Gets the Profile entity for the current user
* or creates it if it doesn't exist
* @param user
* @return user's Profile
*/
private static Profile getProfileFromUser(User user) {
// First fetch the user's Profile from the datastore.
Profile profile = ofy().load().key(
Key.create(Profile.class, user.getUserId())).now();
if (profile == null) {
// Create a new Profile if it doesn't exist.
// Use default displayName and teeShirtSize
String email = user.getEmail();
profile = new Profile(user.getUserId(),
extractDefaultDisplayNameFromEmail(email), email, TeeShirtSize.NOT_SPECIFIED);
}
return profile;
}
/**
* Creates a new Conference object and stores it to the datastore.
*
* @param user A user who invokes this method, null when the user is not signed in.
* @param conferenceForm A ConferenceForm object representing user's inputs.
* @return A newly created Conference Object.
* @throws UnauthorizedException when the user is not signed in.
*/
@ApiMethod(name = "createConference", path = "conference", httpMethod = HttpMethod.POST)
public Conference createConference(final User user, final ConferenceForm conferenceForm)
throws UnauthorizedException {
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
// Allocate Id first, in order to make the transaction idempotent.
final String userId = user.getUserId();
Key<Profile> profileKey = Key.create(Profile.class, userId);
final Key<Conference> conferenceKey = factory().allocateId(profileKey, Conference.class);
final long conferenceId = conferenceKey.getId();
final Queue queue = QueueFactory.getDefaultQueue();
// Start a transaction.
Conference conference = ofy().transact(new Work<Conference>() {
@Override
public Conference run() {
// Fetch user's Profile.
Profile profile = getProfileFromUser(user);
Conference conference = new Conference(conferenceId, userId, conferenceForm);
// Save Conference and Profile.
ofy().save().entities(conference, profile).now();
queue.add(ofy().getTransaction(),
TaskOptions.Builder.withUrl("/tasks/send_confirmation_email")
.param("email", profile.getMainEmail())
.param("conferenceInfo", conference.toString()));
return conference;
}
});
return conference;
}
@ApiMethod(
name = "queryConferences_nofilters",
path = "queryConferences_nofilters",
httpMethod = HttpMethod.POST
)
public List<Conference> queryConferences_nofilters() {
// Find all entities of type Conference
Query<Conference> query = ofy().load().type(Conference.class).order("name");
return query.list();
}
/**
* Queries against the datastore with the given filters and returns the result.
*
* Normally this kind of method is supposed to get invoked by a GET HTTP method,
* but we do it with POST, in order to receive conferenceQueryForm Object via the POST body.
*
* @param conferenceQueryForm A form object representing the query.
* @return A List of Conferences that match the query.
*/
@ApiMethod(
name = "queryConferences",
path = "queryConferences",
httpMethod = HttpMethod.POST
)
public List<Conference> queryConferences(ConferenceQueryForm conferenceQueryForm) {
Iterable<Conference> conferenceIterable = conferenceQueryForm.getQuery();
List<Conference> result = new ArrayList<>(0);
List<Key<Profile>> organizersKeyList = new ArrayList<>(0);
for (Conference conference : conferenceIterable) {
organizersKeyList.add(Key.create(Profile.class, conference.getOrganizerUserId()));
result.add(conference);
}
// To avoid separate datastore gets for each Conference, pre-fetch the Profiles.
ofy().load().keys(organizersKeyList);
return result;
}
public List<Conference> filterPlayground() {
// Query<Conference> query = ofy().load().type(Conference.class).order("name");
Query<Conference> query = ofy().load().type(Conference.class);
/*
// Filter on city
query = query.filter("city =", "London");
// query = query.filter("city =", "Default City");
// Add a filter for topic = "Medical Innovations"
query = query.filter("topics =", "Medical Innovations");
// Add a filter for maxAttendees
query = query.filter("maxAttendees >", 8);
query = query.filter("maxAttendees <", 10).order("maxAttendees").order("name");
// Add a filter for month {unindexed composite query}
// Find conferences in June
query = query.filter("month =", 6);
*/
// multiple sort orders
query = query.filter("city =", "Tokyo").filter("seatsAvailable <", 10).
filter("seatsAvailable >" , 0).order("seatsAvailable").order("name").
order("month");
return query.list();
}
/**
* Returns a list of Conferences that the user created.
* In order to receive the websafeConferenceKey via the JSON params, uses a POST method.
*
* @param user A user who invokes this method, null when the user is not signed in.
* @return a list of Conferences that the user created.
* @throws UnauthorizedException when the user is not signed in.
*/
@ApiMethod(
name = "getConferencesCreated",
path = "getConferencesCreated",
httpMethod = HttpMethod.POST
)
public List<Conference> getConferencesCreated(final User user) throws UnauthorizedException {
// If not signed in, throw a 401 error.
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
String userId = user.getUserId();
Key<Profile> userKey = Key.create(Profile.class, userId);
return ofy().load().type(Conference.class)
.ancestor(userKey)
.order("name").list();
}
/**
* Just a wrapper for Boolean.
* We need this wrapped Boolean because endpoints functions must return
* an object instance, they can't return a Type class such as
* String or Integer or Boolean
*/
public static class WrappedBoolean {
private final Boolean result;
private final String reason;
public WrappedBoolean(Boolean result) {
this.result = result;
this.reason = "";
}
public WrappedBoolean(Boolean result, String reason) {
this.result = result;
this.reason = reason;
}
public Boolean getResult() {
return result;
}
public String getReason() {
return reason;
}
}
/**
* Returns a Conference object with the given conferenceId.
*
* @param websafeConferenceKey The String representation of the Conference Key.
* @return a Conference object with the given conferenceId.
* @throws NotFoundException when there is no Conference with the given conferenceId.
*/
@ApiMethod(
name = "getConference",
path = "conference/{websafeConferenceKey}",
httpMethod = HttpMethod.GET
)
public Conference getConference(
@Named("websafeConferenceKey") final String websafeConferenceKey)
throws NotFoundException {
Key<Conference> conferenceKey = Key.create(websafeConferenceKey);
Conference conference = ofy().load().key(conferenceKey).now();
if (conference == null) {
throw new NotFoundException("No Conference found with key: " + websafeConferenceKey);
}
return conference;
}
/**
* Register to attend the specified Conference.
*
* @param user An user who invokes this method, null when the user is not signed in.
* @param websafeConferenceKey The String representation of the Conference Key.
* @return Boolean true when success, otherwise false
* @throws UnauthorizedException when the user is not signed in.
* @throws NotFoundException when there is no Conference with the given conferenceId.
*/
@ApiMethod(
name = "registerForConference",
path = "conference/{websafeConferenceKey}/registration",
httpMethod = HttpMethod.POST
)
public WrappedBoolean registerForConference(final User user,
@Named("websafeConferenceKey") final String websafeConferenceKey)
throws UnauthorizedException, NotFoundException,
ForbiddenException, ConflictException {
// If not signed in, throw a 401 error.
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
// Get the userId
final String userId = user.getUserId();
WrappedBoolean result = ofy().transact(new Work<WrappedBoolean>() {
@Override
public WrappedBoolean run() {
try {
// Get the conference key
// Will throw ForbiddenException if the key cannot be created
Key<Conference> conferenceKey = Key.create(websafeConferenceKey);
// Get the Conference entity from the datastore
Conference conference = ofy().load().key(conferenceKey).now();
// 404 when there is no Conference with the given conferenceId.
if (conference == null) {
return new WrappedBoolean (false,
"No Conference found with key: "
+ websafeConferenceKey);
}
// Get the user's Profile entity
Profile profile = getProfileFromUser(user);
// Has the user already registered to attend this conference?
if (profile.getConferenceKeysToAttend().contains(
websafeConferenceKey)) {
return new WrappedBoolean (false, "Already registered");
} else if (conference.getSeatsAvailable() <= 0) {
return new WrappedBoolean (false, "No seats available");
} else {
// All looks good, go ahead and book the seat
profile.addToConferenceKeysToAttend(websafeConferenceKey);
conference.bookSeats(1);
// Save the Conference and Profile entities
ofy().save().entities(profile, conference).now();
// We are booked!
return new WrappedBoolean(true, "Registration successful");
}
}
catch (Exception e) {
return new WrappedBoolean(false, "Unknown exception");
}
}
});
// if result is false
if (!result.getResult()) {
if (result.getReason().contains("No Conference found with key")) {
throw new NotFoundException (result.getReason());
}
else if (result.getReason() == "Already registered") {
throw new ConflictException("You have already registered");
}
else if (result.getReason() == "No seats available") {
throw new ConflictException("There are no seats available");
}
else {
throw new ForbiddenException("Unknown exception");
}
}
return result;
}
/**
* Unregister from the specified Conference.
*
* @param user An user who invokes this method, null when the user is not signed in.
* @param websafeConferenceKey The String representation of the Conference Key to unregister
* from.
* @return Boolean true when success, otherwise false.
* @throws UnauthorizedException when the user is not signed in.
* @throws NotFoundException when there is no Conference with the given conferenceId.
*/
@ApiMethod(
name = "unregisterFromConference",
path = "conference/{websafeConferenceKey}/registration",
httpMethod = HttpMethod.DELETE
)
public WrappedBoolean unregisterFromConference(final User user,
@Named("websafeConferenceKey")
final String websafeConferenceKey)
throws UnauthorizedException, NotFoundException, ForbiddenException, ConflictException {
// If not signed in, throw a 401 error.
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
WrappedBoolean result = ofy().transact(new Work<WrappedBoolean>() {
@Override
public WrappedBoolean run() {
Key<Conference> conferenceKey = Key.create(websafeConferenceKey);
Conference conference = ofy().load().key(conferenceKey).now();
// 404 when there is no Conference with the given conferenceId.
if (conference == null) {
return new WrappedBoolean(false,
"No Conference found with key: " + websafeConferenceKey);
}
// Un-registering from the Conference.
Profile profile = getProfileFromUser(user);
if (profile.getConferenceKeysToAttend().contains(websafeConferenceKey)) {
profile.unregisterFromConference(websafeConferenceKey);
conference.giveBackSeats(1);
ofy().save().entities(profile, conference).now();
return new WrappedBoolean(true);
} else {
return new WrappedBoolean(false, "You are not registered for this conference");
}
}
});
// if result is false
if (!result.getResult()) {
if (result.getReason().contains("No Conference found with key")) {
throw new NotFoundException (result.getReason());
}
else {
throw new ForbiddenException(result.getReason());
}
}
// NotFoundException is actually thrown here.
return new WrappedBoolean(result.getResult());
}
/**
* Returns a collection of Conference Object that the user is going to attend.
*
* @param user An user who invokes this method, null when the user is not signed in.
* @return a Collection of Conferences that the user is going to attend.
* @throws UnauthorizedException when the User object is null.
*/
@ApiMethod(
name = "getConferencesToAttend",
path = "getConferencesToAttend",
httpMethod = HttpMethod.GET
)
public Collection<Conference> getConferencesToAttend(final User user)
throws UnauthorizedException, NotFoundException {
// If not signed in, throw a 401 error.
if (user == null) {
throw new UnauthorizedException("Authorization required");
}
Profile profile = ofy().load().key(Key.create(Profile.class, user.getUserId())).now();
if (profile == null) {
throw new NotFoundException("Profile doesn't exist.");
}
List<String> keyStringsToAttend = profile.getConferenceKeysToAttend();
List<Key<Conference>> keysToAttend = new ArrayList<>();
for (String keyString : keyStringsToAttend) {
keysToAttend.add(Key.<Conference>create(keyString));
}
return ofy().load().keys(keysToAttend).values();
}
@ApiMethod(
name = "getAnnouncement",
path = "announcement",
httpMethod = HttpMethod.GET
)
public Announcement getAnnouncement() {
MemcacheService memcacheService = MemcacheServiceFactory.getMemcacheService();
Object message = memcacheService.get(Constants.MEMCACHE_ANNOUNCEMENTS_KEY);
if (message != null) {
return new Announcement(message.toString());
}
return null;
}
}