Forem: Nicolas Dos Santos

schema-org-java 0.4.0 released - Java library for working with Schema.org data in JSON-LD format

Nicolas Dos Santos — Sun, 12 Feb 2023 21:32:27 +0000

If you've ever worked with structured data, you're probably familiar with Schema.org.

And you must have realized that entities contain a lot of information and that inheritance can be complex.

So it can be tedious to create all the entities needed for your project and then serialize / deserialize the data in JSON-LD format.

schema-org-java is a library to work with Schema.org entities.

The entities can be easily generated with the Maven plugin, and can then be serialized / deserialized to JSON-LD format with the serializer module.

The library has the following features:

Fully supports the vocabulary defined in the http://schema.org namespace.
Fully supports type multiple inheritance, multiple values per property in http://schema.org.
Every Schema.org type has a corresponding Java interface which provides convenient getter/setter methods for getting/setting the values of the properties of that particular type.
Supports the generation of all Schema.org types at once, or specific ones.
Fully supports Schema.org documentation of types and properties by adding Javadoc on generated classes and methods.
Supports different versions of the Schema.org vocabulary.
Supports serializing and deserializing Schema.org objects to and from JSON-LD formats.

Here is a video illustrating the generation and creation of Schema.org entities:

user-images.githubusercontent.com

If you are interested, please take a look and give me your feedback :)

schema-org-java: Java library for working with Schema.org data in JSON-LD format

Nicolas Dos Santos — Mon, 21 Nov 2022 21:49:19 +0000

If you've ever worked with structured data, you're probably familiar with Schema.org.

And you must have realized that entities contain a lot of information and that inheritance can be complex.

So it can be tedious to create all the entities needed for your project and then serialize / deserialize the data in JSON-LD format.

schema-org-java is a library to work with Schema.org entities.

The entities can be easily generated with the Maven plugin, and can then be serialized / deserialized (soon) to JSON-LD format with the serializer module.

The library has the following features:

Fully supports the vocabulary defined in the http://schema.org namespace.
Fully supports type multiple inheritance, multiple values per property in http://schema.org.
Every Schema.org type has a corresponding Java interface which provides convenient getter/setter methods for getting/setting the values of the properties of that particular type.
Supports the generation of all Schema.org types at once, or specific ones.
Fully supports Schema.org documentation of types and properties by adding Javadoc on generated classes and methods.
Supports different versions of the Schema.org vocabulary.
Supports serializing and deserializing (soon) Schema.org objects to and from JSON-LD formats.

Here is a video illustrating the generation and creation of Schema.org entities:

user-images.githubusercontent.com

Several features are not yet developed:

Deserialization
Adding methods to set the data of the fields in list
Added javadoc on setter methods
...

If you are interested, please take a look and give me your feedback :)

Weedow Searchy 0.1.0 released

Nicolas Dos Santos — Tue, 23 Feb 2021 10:24:58 +0000

I'm happy to share with you the release 0.1.0 of Weedow Searchy.

Searchy is a Spring-based library that allows to automatically expose endpoints in order to search for data related to Entities, whatever the database used.

Searchy provides an advanced search engine that does not require the creation of Repositories with custom methods needed to search on different fields of Entities.

We can search on any field, combine multiple criteria to refine the search, and even search on nested fields.

It supports the following data access layers:

JPA
MongoDB

Examples of queries:

GET /search/person

GET /search/person?firstName=John

GET /search/person?address.zipCode=78370

GET /search/person?query=firstName='John' AND lastName='Doe'

GET /search/person?query=birthday != '1981-03-12T10:36:00'

GET /search/person?query=NOT(firstName='John' OR firstName='Jane')

GET /search/person?query=address.street IMATCHES 'RUE*' AND (vehicles.brand='Renault' OR vehicles.brand='Porsche') AND job.active = true AND (job.salary >=50000 AND job.salary<610000) AND characteristics.key = 'hair' AND vehicles.features.value.description IMATCHES '*Navigation Services*'

There is a "Getting Started" section that describes step by step the creation of an application with the library.

Searchy provides several features described in the documentation:

DTO Mappers
Validators
Entity joins handling
Converters
...

Spring Data Search 2.0.0 released

Nicolas Dos Santos — Tue, 05 Jan 2021 12:21:18 +0000

I'm happy to share with you the release 2.0.0 of Spring Data Search.

This library allows to automatically expose endpoints in order to search for data related to Entities.

It provides an advanced search engine that can search on any Entity field, combine multiple criteria to refine the search, and even search on nested Entity fields.

Kobee1203 / spring-data-search

Automatically exposes Entity endpoints to search for data using a powerful query language

There are some new features, and some fixed bugs.
But above all there was a core refactoring to support different data access layers (JPA, MongoDB, ...).
Currently, there is only JPA supported (which was already supported by previous versions). But the next step is to add support to MongoDB.

This refactoring required some modifications in the APIs.
There is a page describing how to migrate from 1.x to 2.x.

Whats's new:

Allow special keywords to be used as query values:
- CURRENT_DATE: keyword representing the current date. Similar to the current_date() function in SQL.
- CURRENT_TIME: keyword representing the current time. Similar to the current_time() function in SQL
- CURRENT_DATE_TIME: keyword representing the current date time. Similar to the current_timestamp() function in SQL
Application property spring.data.search.default-alias-resolver.field-suffixes: Comma-separated list of field suffixes to be removed in order to create a field's alias from the com.weedow.spring.data.search.config.DefaultAliasResolver. Default value is Entity,Entities
Improved search on fields of Map type: You can use the special keys key or value to query the keys or values respectively. And now, you can query on the nested fields of the Objects representing by key or value
- /search/person?tasks.key.name=shopping
- /search/person?vehicles.features.value.name=gps

If you are interested and want to know more, please go to the project page where you will find all the details.

Spring Data Search 1.0.1 released

Nicolas Dos Santos — Wed, 04 Nov 2020 21:35:38 +0000

I'm happy to share with you the release 1.0.1 of Spring Data Search.
This library allows to automatically expose endpoints to search for data using a powerful query language.

What's New:

Changing the base path
Handle Map type fields on Entities
Support for Reactive application
2 new sample applications added in Java and in Spring WebFlux, available in the distribution zip

Kobee1203 / spring-data-search

Automatically exposes endpoints to search for data using a powerful query language

If you don't know this library, let me briefly explain its purpose and how to set it up in 5 minutes.

About

Spring Data Search allows to automatically expose endpoints in order to search for data related to JPA entities.

Spring Data Search provides an advanced search engine that does not require the creation of JPA repositories with custom methods needed to search on different fields of JPA entities.

We can search on any field, combine multiple criteria to refine the search, and even search on nested fields.

Why use Spring Data Search?

Spring Data Rest builds on top of the Spring Data repositories and automatically exports those as REST resources.

However, when we want to search for JPA entities according to different criteria, we need to define several methods in the Repositories to perform different searches.

Moreover, by default REST endpoints return JPA Entities content directly to the client, without mapping with a dedicated DTO class.
We can use Projections on Repositories, but this means that from the architecture level, we strongly associate the infrastructure layer with the application layer.

Spring Data Search allows to easily expose an endpoint for a JPA entity and thus be able to search on any fields of this entity, to combine several criteria and even search on fields belonging to sub-entities.

Let's say you manage Persons associated with Addresses, Vehicles and a Job.
You want to allow customers to search for them, regardless of the search criteria:

Search for Persons whose first name is "John" or "Jane"
Search for Persons whose company where they work is "Acme", and own a car or a motorbike
Search for Persons who live in London

You could create a Repository with custom methods to perform all these searches, and you could add new custom methods according to the needs.

Alternatively, you can use Spring Data Search which allows you to perform all these searches with a minimum configuration, without the need of a custom Repository. If you want to do other different searches, you do not need to add new methods to do that.

Getting Started in 5 minutes

Go to https://start.spring.io/
Generate a new Java project sample-app-java with the following dependencies:
- Spring Web
- Spring Data JPA
- H2 Database

Update the generated project by adding the dependency of Spring Data Search:

For Maven project, add the dependency in the pom.xml file:

<dependency>
  <groupId>com.weedow</groupId>
  <artifactId>spring-data-search</artifactId>
  <version>1.0.1</version>
</dependency>

For Gradle project, add the dependency in the build.gradle file:

implementation "com.weedow:spring-data-search:1.0.1"

Create a new file Person.java to add a new JPA Entity Person with the following content:

import javax.persistence.*;
import java.time.LocalDateTime;
import java.util.Set;

@Entity
public class Person {

    @Id
    @GeneratedValue
    private Long id;

    @Column(nullable = false)
    private String firstName;

    @Column(nullable = false)
    private String lastName;

    @Column(unique = true, length = 100)
    private String email;

    @Column
    private LocalDateTime birthday;

    @Column
    private Double height;

    @Column
    private Double weight;

    @ElementCollection(fetch = FetchType.EAGER)
    private Set<String> nickNames;

    @ElementCollection
    @CollectionTable(name = "person_phone_numbers", joinColumns = {@JoinColumn(name = "person_id")})
    @Column(name = "phone_number")
    private Set<String> phoneNumbers;

    public Long getId() {
        return id;
    }

    public Person setId(Long id) {
        this.id = id;
        return this;
    }

    public String getFirstName() {
        return firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public String getEmail() {
        return email;
    }

    public LocalDateTime getBirthday() {
        return birthday;
    }

    public Double getHeight() {
        return height;
    }

    public Double getWeight() {
        return weight;
    }

    public Set<String> getNickNames() {
        return nickNames;
    }

    public Person setNickNames(Set<String> nickNames) {
        this.nickNames = nickNames;
        return this;
    }

    public Set<String> getPhoneNumbers() {
        return phoneNumbers;
    }

    public Person setPhoneNumbers(Set<String> phoneNumbers) {
        this.phoneNumbers = phoneNumbers;
        return this;
    }

    public boolean equals(Object object) {
        if (this == object) {
            return true;
        }
        if (object == null || getClass() != object.getClass()) {
            return false;
        }
        if (!super.equals(object)) {
            return false;
        }

        Person person = (Person) object;

        if (!firstName.equals(person.firstName)) {
            return false;
        }
        if (!lastName.equals(person.lastName)) {
            return false;
        }

        return true;
    }

    public int hashCode() {
        int result = super.hashCode();
        result = 31 * result + firstName.hashCode();
        result = 31 * result + lastName.hashCode();
        return result;
    }
}

Add the following Configuration class to add a new SearchDescriptor:

import com.example.sampleappjava.entity.Person;
import com.weedow.spring.data.search.config.SearchConfigurer;
import com.weedow.spring.data.search.descriptor.SearchDescriptor;
import com.weedow.spring.data.search.descriptor.SearchDescriptorBuilder;
import com.weedow.spring.data.search.descriptor.SearchDescriptorRegistry;
import org.springframework.context.annotation.Configuration;

@Configuration
public class SampleAppJavaConfiguration implements SearchConfigurer {

    @Override
    public void addSearchDescriptors(SearchDescriptorRegistry registry) {
        registry.addSearchDescriptor(personSearchDescriptor());
    }

    private SearchDescriptor<Person> personSearchDescriptor() {
        return new SearchDescriptorBuilder<Person>(Person.class).build();
    }
}

Create a new file data.sql in /src/main/resources, and add the following content:

  INSERT INTO PERSON (id, first_name, last_name, email, birthday, height, weight)
      VALUES (1, 'John', 'Doe', 'john.doe@acme.com', '1981-03-12 10:36:00', 174.0, 70.5);
  INSERT INTO PERSON (id, first_name, last_name, email, birthday, height, weight)
      VALUES (2, 'Jane', 'Doe', 'jane.doe@acme.com', '1981-11-26 12:30:00', 165.0, 68.0);

  INSERT INTO PERSON_PHONE_NUMBERS (person_id, phone_number) VALUES (1, '+33612345678');
  INSERT INTO PERSON_PHONE_NUMBERS (person_id, phone_number) VALUES (2, '+33687654321');

  INSERT INTO PERSON_NICK_NAMES (person_id, nick_names) VALUES (1, 'Johnny');
  INSERT INTO PERSON_NICK_NAMES (person_id, nick_names) VALUES (1, 'Joe');

Run the application:
- For Maven Project: ./mvnw spring-boot:run
- For Gradle Project: ./gradlew bootRun
- From your IDE: Run the Main Class com.example.sampleappjava.SampleAppJavaApplication
Open your browser and go to the URL http://localhost:8080/search/person
You can filter the results by adding query parameters representing the JPA Entity fields. Here is an example where the results are filtered by the first name:

You can also filter using the Advanced Query.

If you are interested and want to know more, please go to the project page where you will find all the details.