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Spring data mongodb query add boolean field if value exists in array

I'm trying to query some data from mongoDb which contains likes array. Each like object holds user.id of liker.
I need an extra boolean field that says if document is liked by user or not. So I need isLiked to be true if user has liked the document.
Here is what I have done till now:
I used ConditionalOperators.Cond to check if likes.userId is equal to userId of visitor.
#Override
public List<PostExtra> findPostsNearBy(double[] point, Distance distance, String thisUserId) {
mongoTemplate.indexOps(CheckInEntity.class).ensureIndex(new GeospatialIndex("position"));
ConditionalOperators.Cond conditionalOperators = new ConditionalOperators.ConditionalOperatorFactory(Criteria.where("likes.userId").is(thisUserId)).then(true).otherwise(false);
Aggregation aggregation = Aggregation.newAggregation(
Aggregation.geoNear(
locationBasedOperationHelper.findNear(point,distance)
.query(new Query(privacyConsideredOperationHelper.privacyConsideredQuery(userRelationsEntity)))
,"distance"
),
//Aggregation.unwind("likes"),
Aggregation.project("user", "description").and(conditionalOperators).as("isLiked")
);
final AggregationResults<PostExtra> results =
mongoTemplate.aggregate(aggregation, PostEntity.class, PostExtra.class);
return results.getMappedResults();
}
if I remove the comment on Aggregation.unwind("likes") I can only get posts that this user has liked not those he hasn't.
I have seen the same matter here but I dont know whats the MontoTemplate code related to that?
Also I have seen approaches with setIsSubset, still I dont know java implementation.
I'm using spring boot 2.0.4.RELEASE and spring-boot-starter-data-mongodb.
#Document(collection = EntityCollectionNames.POST_COLLECTION_NAME)
public class PostEntity{
#Id
private String id;
#Field
#DBRef
#Indexed
private UserEntity user;
#GeoSpatialIndexed(type = GeoSpatialIndexType.GEO_2DSPHERE)
#Field(value = "position")
private Point position;
#Field(value = "description")
private String description;
#Field
private int likesCount;
#Field
private List<LikeEntity> likes;
}
Post Extra:
public class PostExtra extends PostEntity {
private double distance;
private boolean isLiked;
}
Like:
public class LikeEntity {
#Field
private String userId;
}

After some searching I found out to do it without using unwind I need to implement something like this to project isLiked field:
$cond:[
{$gt:[
{$size:
{$setIntersection:["$likes.userId",userIdsToCheckIn]}
},0]
},true,false]
I tried to do it in spring like this:
ConditionalOperators.Cond conditionalOperators = new ConditionalOperators.ConditionalOperatorFactory(
ComparisonOperators.Gt.valueOf(
ArrayOperators.Size.lengthOfArray(
SetOperators.SetIntersection.arrayAsSet("$likes.userId").intersects(????????)
)
).greaterThanValue(0)
).then(true).otherwise(false);
But I didnt know what to pass to intersects() method and apparently Spring does not let you pass List or Array as that input. Then I found out I can implement my own AggregationExpressions and override toDocument() method.
So I came up with this and it worked:
ConditionalOperators.Cond conditionalOperators = new ConditionalOperators.ConditionalOperatorFactory(
new AggregationExpression() {
#Override
public Document toDocument(AggregationOperationContext aggregationOperationContext) {
return Document.parse("{$gt:[{$size:{$setIntersection:[\"$likes.userId\",[\""+userId+"\"]]}},0]}");
}
}
).then(true).otherwise(false);
Ofcourse I could add $cond to the implementation directly too.
I would still like to know if there are any spring solutions that does not contain mongodb queries directly for this.

spring data elasticsearch dynamic multi tenant index mismatch?

I am experimenting with spring data elasticsearch by implementing a cluster which will host multi-tenant indexes, one index per tenant.
I am able to create and set settings dynamically for each needed index, like
public class SpringDataES {
#Autowired
private ElasticsearchTemplate es;
#Autowired
private TenantIndexNamingService tenantIndexNamingService;
private void createIndex(String indexName) {
Settings indexSettings = Settings.builder()
.put("number_of_shards", 1)
.build();
CreateIndexRequest indexRequest = new CreateIndexRequest(indexName, indexSettings);
es.getClient().admin().indices().create(indexRequest).actionGet();
es.refresh(indexName);
}
private void preapareIndex(String indexName){
if (!es.indexExists(indexName)) {
createIndex(indexName);
}
updateMappings(indexName);
}
The model is created like this
#Document(indexName = "#{tenantIndexNamingService.getIndexName()}", type = "movies")
public class Movie {
#Id
#JsonIgnore
private String id;
private String movieTitle;
#CompletionField(maxInputLength = 100)
private Completion movieTitleSuggest;
private String director;
private Date releaseDate;
where the index name is passed dynamically via the SpEl
#{tenantIndexNamingService.getIndexName()}
that is served by
#Service
public class TenantIndexNamingService {
private static final String INDEX_PREFIX = "test_index_";
private String indexName = INDEX_PREFIX;
public TenantIndexNamingService() {
}
public String getIndexName() {
return indexName;
}
public void setIndexName(int tenantId) {
this.indexName = INDEX_PREFIX + tenantId;
}
public void setIndexName(String indexName) {
this.indexName = indexName;
}
}
So, whenever I have to execute a CRUD action, first I am pointing to the right index and then to execute the desired action
tenantIndexNamingService.setIndexName(tenantId);
movieService.save(new Movie("Dead Poets Society", getCompletion("Dead Poets Society"), "Peter Weir", new Date()));
My assumption is that the following dynamically index assignment, will not work correctly in a multi-threaded web application:
#Document(indexName = "#{tenantIndexNamingService.getIndexName()}"
This is because TenantIndexNamingService is singleton.
So my question is how achieve the right behavior in a thread save manner?

I would probably go with an approach similar to the following one proposed for Cassandra:
https://dzone.com/articles/multi-tenant-cassandra-cluster-with-spring-data-ca
You can have a look at the related GitHub repository here:
https://github.com/gitaroktato/spring-boot-cassandra-multitenant-example
Now, since Elastic has differences in how you define a Document, you should mainly focus in defining a request-scoped bean that will encapsulate your tenant-id and bind it to your incoming requests.

Here is my solution. I create a RequestScope bean to hold the indexes per HttpRequest
how does singleton bean handle dynamic index

Merging several Flux into one from Mongo Collection

I am a bit new to spring reactive programming. I am currently developing an app using spring-boot-starter-webflux:2.0.0.M5.
I have a Foodtruck mongodb model which contains menus :
#Document(collection = "Foodtruck")
#lombok.Getter
#lombok.Setter
#lombok.NoArgsConstructor
#lombok.AllArgsConstructor
public class Foodtruck {
#Id
private String id;
#URL
private String siteUrl;
#NotBlank
private String name;
private String description;
#NotBlank
private String address;
private List<Menu> menus;
#JsonIgnore
private GridFS image;
}
And here is the model for Menu :
#lombok.Getter
#lombok.Setter
#lombok.NoArgsConstructor
#lombok.AllArgsConstructor
#Document(collection = "menus")
public class Menu {
#Id
private String id;
private List<DayOfWeek> days;
#NotBlank
private String label;
private String description;
private Double price;
private List<Dish> dishes;
#JsonIgnore
private GridFS image;
}
To get all my menus, I first need to get all my restaurants and then merge all the Flux obtained, and return them through my rest controller.
Here is the service I call from my rest resource :
#Service
public class MenuServiceImpl implements MenuService {
FoodtruckService foodtruckService;
public MenuServiceImpl(FoodtruckService foodtruckService) {
this.foodtruckService = foodtruckService;
}
#Override
public Flux<Menu> getAllMenus() {
Flux<Menu> allMenuFlux = Flux.empty();
Flux<Foodtruck> foodtruckFlux = foodtruckService.getAllFoodtrucks();
foodtruckFlux.toStream().forEach(foodtruck -> {
Flux<Menu> currentMenuFlux = Flux.fromIterable(foodtruck.getMenus());
allMenuFlux.mergeWith(currentMenuFlux);
});
return allMenuFlux;
}
}
The mergeWith does not seems to add anything to allMenuFlux. I think I have an understanding problem here.
I have been through the documentation, tested other methods like concat or zip, but it does not interleave flux events as I wish. I can't manage to merge these Flux correctly.
I also think there is a better way to get mongo embedded documents through a menu repository, since my method seems to be a bit overkill, and can cause performance problems in the long run. I have tried and it does not work.
EDIT:
After trying the following code (Being sure that my list is not empty), the resulting fluxtest3 variable is merged correctly :
Flux<Menu> allMenuFlux = Flux.empty();
Flux<Foodtruck> foodtruckFlux = foodtruckService.getAllFoodtrucks();
List<Foodtruck> test = foodtruckFlux.collectList().block();
Flux<Menu> fluxtest1 = Flux.fromIterable(test.get(0).getMenus());
Flux<Menu> fluxtest2 = Flux.fromIterable(test.get(1).getMenus());
Flux<Menu> fluxtest3 = fluxtest1.mergeWith(fluxtest2);
But that's not exactly what I want. Why isn't it working with an empty flux as parent flux.
What am I missing here ?
Thanks in advance for your help.

I think there are a couple of misunderstandings at work here.
If you ever convert a Flux to a Collection, Stream or similar and then something obtained from that back to a Flux you are most certainly doing something wrong. These classes force your pipeline to collect multiple elements, then process them and then convert them back to a Flux. In almost every case this should be possible just with operations offered by Flux.
The methods on Flux don't change the Flux but create new instances with additional behavior. So if you have code like this:
Flux<Menu> allMenuFlux = Flux.empty();
Flux<Foodtruck> foodtruckFlux = foodtruckService.getAllFoodtrucks();
foodtruckFlux.toStream().forEach(foodtruck -> {
Flux<Menu> currentMenuFlux = Flux.fromIterable(foodtruck.getMenus());
allMenuFlux.mergeWith(currentMenuFlux);
});
return allMenuFlux;
Everytime you call allMenuFlux.mergeWith(currentMenuFlux); you create a new Flux just so the Garbage Collector can take care of it. allMenuFlux is still the empty `Flux you started with.
What you really seem to want is:
return foodtruckService.getAllFoodtrucks()
.flatMap(Foodtruck::getMenus);
See the documentation for flatMap. The difference between flatMap and mergeWith is that mergeWith keeps the original elements. Which is superfluous if there are none as in your use-cases.
Bonus: Your additional question
Flux<Menu> fluxtest1 = Flux.fromIterable(test.get(0).getMenus());
Flux<Menu> fluxtest2 = Flux.fromIterable(test.get(1).getMenus());
Flux<Menu> fluxtest3 = fluxtest1.mergeWith(fluxtest2);
Here you are not returning the original fluxtest1 but the newly generated fluxtest2. Therefore it does work.

Vaadin with SpringBoot

Hi SO i'm newbie in Vaadin, tries to create form and bind to that POJO object.
...Some declaration
Binder<User> binder = new Binder<>(User.class);
#Autowired
public FormUser(UserRepository userRepository, AuthorityRepository authorityRepository){
this.userRepository = userRepository;
this.authorityRepository = authorityRepository;
authorities = new ListSelect<>("Authorities", authorityRepository.findAll());
authorities.setItemCaptionGenerator(Authority::getAuthority);
//Set items
username.setIcon(FontAwesome.USER);
password.setIcon(FontAwesome.USER_SECRET);
saveButton.addClickListener(e -> {
userRepository.save(user);
});
setSpacing(true);
addComponents(username, password, authorities, saveButton);
binder.bindInstanceFields(this);
}
When try to access view that contains FormUser get this error:
java.lang.IllegalStateException: Property type 'java.util.Collection' doesn't match the field type 'java.util.Set< dev.gva.model.Authority >'. Binding should be configured manually using converter.
Authority :
public class Authority{
private Long id;
private String authority;
getter/setters..
}
User:
public class User{
private Long id;
private Collection<Authority> authorities;
other fields, getters/setters...
}
How to write this converter? Thanks

Instead adding boilerplate code for conversions you should use Set or List for your authorities-attribute within the User-class. An advantage of that would be also that no duplicates are allowed in authorities. The difference between Set and List is that List is ordered and could be accessed by an index. You decide what you need, but Set might be enough.

Spring Data Elasticsearch: Multiple Index with same Document

I'm using spring-data-elasticsearch and for the beginning everything works fine.
#Document( type = "products", indexName = "empty" )
public class Product
{
...
}
public interface ProductRepository extends ElasticsearchRepository<Product, String>
{
...
}
In my model i can search for products.
#Autowired
private ProductRepository repository;
...
repository.findByIdentifier( "xxx" ).getCategory() );
So, my problem is - I've the same Elasticsearch type in different indices and I want to use the same document for all queries. I can handle more connections via a pool - but I don't have any idea how I can implement this.
I would like to have, something like that:
ProductRepository customerRepo = ElasticsearchPool.getRepoByCustomer("abc", ProductRepository.class);
repository.findByIdentifier( "xxx" ).getCategory();
Is it possible to create a repository at runtime, with an different index ?
Thanks a lot
Marcel

Yes. It's possible with Spring. But you should use ElasticsearchTemplate instead of Repository.
For example. I have two products. They are stored in different indices.
#Document(indexName = "product-a", type = "product")
public class ProductA {
#Id
private String id;
private String name;
private int value;
//Getters and setters
}
#Document(indexName = "product-b", type = "product")
public class ProductB {
#Id
private String id;
private String name;
//Getters and setters
}
Suppose if they have the same type, so they have the same fields. But it's not necessary. Two products can have totally different fields.
I have two repositories:
public interface ProductARepository extends ElasticsearchRepository<ProductA, String> {
}
public interface ProductBRepository
extends ElasticsearchRepository<ProductB, String> {
}
It's not necessary too. Only for testing. The fact that ProductA is stored in "product-a" index and ProductB is stored in "product-b" index.
How to query two(ten, dozen) indices with the same type?
Just build custom repository like this
#Repository
public class CustomProductRepositoryImpl {
#Autowired
private ElasticsearchTemplate elasticsearchTemplate;
public List<ProductA> findProductByName(String name) {
MatchQueryBuilder queryBuilder = QueryBuilders.matchPhrasePrefixQuery("name", name);
//You can query as many indices as you want
IndicesQueryBuilder builder = QueryBuilders.indicesQuery(queryBuilder, "product-a", "product-b");
SearchQuery searchQuery = new NativeSearchQueryBuilder().withQuery(builder).build();
return elasticsearchTemplate.query(searchQuery, response -> {
SearchHits hits = response.getHits();
List<ProductA> result = new ArrayList<>();
Arrays.stream(hits.getHits()).forEach(h -> {
Map<String, Object> source = h.getSource();
//get only id just for test
ProductA productA = new ProductA()
.setId(String.valueOf(source.getOrDefault("id", null)));
result.add(productA);
});
return result;
});
}
}
You can search as many indices as you want and you can transparently inject this behavior into ProductARepository adding custom behavior to single repositories
Second solution is to use indices aliases, but you had to create custom model or custom repository too.

We can use the withIndices method to switch the index if needed:
NativeSearchQueryBuilder nativeSearchQueryBuilder = nativeSearchQueryBuilderConfig.getNativeSearchQueryBuilder();
// Assign the index explicitly.
nativeSearchQueryBuilder.withIndices("product-a");
// Then add query as usual.
nativeSearchQueryBuilder.withQuery(allQueries)
The #Document annotation in entity will only clarify the mapping, to query against a specific index, we still need to use above method.
#Document(indexName="product-a", type="_doc")