mongo example with new mongock added

2026-06-20 11:14:34 +00:00 · 2020-07-17 01:10:42 +04:00
parent 07e27ac35a
commit d47ea85f45
36 changed files with 831 additions and 16 deletions
@@ -30,6 +30,11 @@
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+        </dependency>
+
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
@@ -0,0 +1,17 @@
+package ru.otus.spring.rest;
+
+import org.junit.jupiter.api.extension.ExtendWith;
+import org.springframework.boot.test.autoconfigure.web.servlet.WebMvcTest;
+import org.springframework.boot.test.mock.mockito.MockBean;
+import org.springframework.test.context.junit.jupiter.SpringExtension;
+
+import static org.junit.jupiter.api.Assertions.*;
+
+@WebMvcTest
+@ExtendWith(SpringExtension.class)
+class PersonControllerTest {
+
+    @org.junit.jupiter.api.Test
+    void listPage() {
+    }
+}
@@ -1,6 +1,8 @@
 package ru.otus.example.ormdemo.models;

 import lombok.*;
+import org.hibernate.annotations.Fetch;
+import org.hibernate.annotations.FetchMode;

 import javax.persistence.*;
 import java.util.List;
@@ -10,6 +12,8 @@ import java.util.List;
@AllArgsConstructor
@Entity // Указывает, что данный класс является сущностью
@Table(name = "otus_students") // Задает имя таблицы, на которую будет отображаться сущность
+@NamedEntityGraph(name = "otus-student-avatars-entity-graph",
+        attributeNodes = {@NamedAttributeNode("avatar")})
 public class OtusStudent {
    @Id // Позволяет указать какое поле является идентификатором
    @GeneratedValue(strategy = GenerationType.IDENTITY) // Стратегия генерации идентификаторов
@@ -30,6 +34,7 @@ public class OtusStudent {
    @JoinColumn(name = "student_id")
    private List<EMail> emails;

+    @Fetch(FetchMode.SUBSELECT)
    // Указывает на связь между таблицами "многие ко многим"
    @ManyToMany(targetEntity = Course.class, fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    // Задает таблицу связей между таблицами для хранения родительской и связанной сущностью
@@ -4,10 +4,7 @@ import org.springframework.stereotype.Repository;
 import org.springframework.transaction.annotation.Transactional;
 import ru.otus.example.ormdemo.models.OtusStudent;

-import javax.persistence.EntityManager;
-import javax.persistence.PersistenceContext;
-import javax.persistence.Query;
-import javax.persistence.TypedQuery;
+import javax.persistence.*;
 import java.util.Collections;
 import java.util.List;
 import java.util.Optional;
@@ -26,31 +23,55 @@ public class OtusStudentRepositoryJpaImpl implements OtusStudentRepositoryJpa {

    @Override
    public OtusStudent save(OtusStudent student) {
-        return null;
+        if (student.getId() == 0) {
+            Query query = em.createQuery("insert into OtusStudent (name) " +
+                    "select :name from OtusStudent s");
+            query.setParameter("name", student.getName());
+            query.executeUpdate();
+            return student;
+        } else {
+            return em.merge(student);
+        }
    }

    @Override
-    public Optional<OtusStudent> findById(long id) {
-        return Optional.empty();
+    public Optional<OtusStudent> findById (long id) {
+        return Optional.ofNullable(em.find(OtusStudent.class, id));
    }

    @Override
    public List<OtusStudent> findAll() {
-        return Collections.emptyList();
+        EntityGraph<?> entityGraph = em.getEntityGraph("otus-student-avatars-entity-graph");
+        TypedQuery<OtusStudent> query = em.createQuery("select s from OtusStudent s join fetch s.emails", OtusStudent.class);
+        query.setHint("javax.persistence.fetchgraph", entityGraph);
+        return query.getResultList();
    }

    @Override
    public List<OtusStudent> findByName(String name) {
-        return Collections.emptyList();
+        TypedQuery<OtusStudent> query = em.createQuery
+                ("select s from OtusStudent s where s.name = :name", OtusStudent.class);
+        query.setParameter("name", name);
+        return query.getResultList();
    }

    @Override
    public void updateNameById(long id, String name) {
-
+        Query query = em.createQuery("update OtusStudent s " +
+                "set s.name = :name " +
+                "where s.id = :id");
+        query.setParameter("name", name);
+        query.setParameter("id", id);
+        query.executeUpdate();
    }

    @Override
    public void deleteById(long id) {
+        Query query = em.createQuery("delete " +
+                "from OtusStudent s " +
+                "where s.id = :id");
+        query.setParameter("id", id);
+        query.executeUpdate();
    }

 }
@@ -27,7 +27,7 @@ class OtusStudentRepositoryJpaImplTest {
    private static final long FIRST_STUDENT_ID = 1L;
    private static final String FIRST_STUDENT_NAME = "student_01";

-    private static final int EXPECTED_QUERIES_COUNT = 31;
+    private static final int EXPECTED_QUERIES_COUNT = 2;

    private static final String STUDENT_AVATAR_URL = "где-то там";
    private static final String STUDENT_EMAIL = "any@mail.com";
@@ -43,6 +43,7 @@ class OtusStudentRepositoryJpaImplTest {
    @DisplayName(" должен загружать информацию о нужном студенте по его id")
    @Test
    void shouldFindExpectedStudentById() {
+
        val optionalActualStudent = repositoryJpa.findById(FIRST_STUDENT_ID);
        val expectedStudent = em.find(OtusStudent.class, FIRST_STUDENT_ID);
        assertThat(optionalActualStudent).isPresent().get()
@@ -37,8 +37,6 @@ public class OtusStudent {
    @JoinColumn(name = "student_id")
    private List<EMail> emails;

-    @Fetch(FetchMode.SELECT)
-    @BatchSize(size = 5)
    // Указывает на связь между таблицами "многие ко многим"
    @ManyToMany(targetEntity = Course.class, fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    // Задает таблицу связей между таблицами для хранения родительской и связанной сущностью
@@ -47,6 +47,8 @@ class OtusStudentRepositoryJpaImplTest {

        System.out.println("\n\n\n\n----------------------------------------------------------------------------------------------------------");
        val students = repositoryJpa.findAll();
+        val student = repositoryJpa.findById(1L);
+
        assertThat(students).isNotNull().hasSize(EXPECTED_NUMBER_OF_STUDENTS)
                .allMatch(s -> !s.getName().equals(""))
                .allMatch(s -> s.getCourses() != null && s.getCourses().size() > 0)
@@ -257,6 +257,7 @@ class EmployeeRepositoryImplTest {
        BigDecimal newSalary = oldSalary.multiply(new BigDecimal(2));
        em.detach(employee3);
        employeeRepository.doubleEmployeesSalary(oldSalary);
+        //em.refresh(employee3);

        employee3 = em.find(Employee.class, THIRD_EMPLOYEE_ID);
        assertThat(employee3.getSalary()).isEqualTo(newSalary);
@@ -271,7 +272,7 @@ class EmployeeRepositoryImplTest {
        assertThat(employee8).isNotNull();
        employeeRepository.deleteEmployeesWithoutDepartment();

-        em.clear();
+        em.flush();

        employee2 = em.find(Employee.class, SECOND_EMPLOYEE_ID);
        employee8 = em.find(Employee.class, EIGTH_EMPLOYEE_ID);
@@ -0,0 +1,29 @@
+HELP.md
+/target/
+!.mvn/wrapper/maven-wrapper.jar
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+/build/
+
+### VS Code ###
+.vscode/
@@ -0,0 +1,7 @@
+## Пример работы с MongoDB
+
+В примере демонстрируется:
+* *два подхода к хранению вложенных сущностей*
+* *инициализация базы данными с помощью инструмента миграций Mongock*   
+* *использование AbstractMongoEventListener для выполнения каскадных операций*
+* *работа с массивами с помощью агрегаций и Criteria api*
@@ -0,0 +1,130 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <parent>
+        <groupId>org.springframework.boot</groupId>
+        <artifactId>spring-boot-starter-parent</artifactId>
+        <version>2.3.1.RELEASE</version>
+        <relativePath/> <!-- lookup parent from repository -->
+    </parent>
+
+    <groupId>ru.otus.example</groupId>
+    <artifactId>mongo-db-demo</artifactId>
+    <version>0.0.1-SNAPSHOT</version>
+    <name>mongo-db-demo</name>
+    <description>Demo project for MongoDB</description>
+
+    <properties>
+        <java.version>11</java.version>
+        <maven.compiler.sourcre>11</maven.compiler.sourcre>
+        <maven.compiler.target>11</maven.compiler.target>
+        <mongock.version>4.1.2.BETA</mongock.version>
+    </properties>
+
+    <dependencies>
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-data-mongodb</artifactId>
+
+        </dependency>
+
+        <dependency>
+            <groupId>org.projectlombok</groupId>
+            <artifactId>lombok</artifactId>
+            <optional>true</optional>
+        </dependency>
+
+        <!-- https://mvnrepository.com/artifact/com.github.cloudyrock.mongock/mongock-spring-v5 -->
+        <dependency>
+            <groupId>com.github.cloudyrock.mongock</groupId>
+            <artifactId>mongock-spring-v5</artifactId>
+            <version>${mongock.version}</version>
+        </dependency>
+
+        <dependency>
+            <groupId>com.github.cloudyrock.mongock</groupId>
+            <artifactId>mongodb-springdata-v3-driver</artifactId>
+            <version>${mongock.version}</version>
+        </dependency>
+
+
+
+        <dependency>
+            <groupId>org.springframework.boot</groupId>
+            <artifactId>spring-boot-starter-test</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+        <!--Тестирование-->
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-api</artifactId>
+            <version>${junit-jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-engine</artifactId>
+            <version>${junit-jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter-params</artifactId>
+            <version>${junit-jupiter.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-core</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.mockito</groupId>
+            <artifactId>mockito-junit-jupiter</artifactId>
+            <version>${mockito.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>org.assertj</groupId>
+            <artifactId>assertj-core</artifactId>
+            <version>${assertj.version}</version>
+            <scope>test</scope>
+        </dependency>
+
+        <dependency>
+            <groupId>de.flapdoodle.embed</groupId>
+            <artifactId>de.flapdoodle.embed.mongo</artifactId>
+            <scope>test</scope>
+        </dependency>
+
+
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.springframework.boot</groupId>
+                <artifactId>spring-boot-maven-plugin</artifactId>
+            </plugin>
+        </plugins>
+    </build>
+
+    <repositories>
+        <repository>
+            <id>spring-milestones</id>
+            <name>Spring Milestones</name>
+            <url>https://repo.spring.io/milestone</url>
+        </repository>
+    </repositories>
+
+</project>
@@ -0,0 +1,16 @@
+package ru.otus.example.mongodbdemo;
+
+import com.github.cloudyrock.spring.v5.EnableMongock;
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+
+@EnableMongock
+@SpringBootApplication
+@EnableConfigurationProperties
+public class MongoDbDemoApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(MongoDbDemoApplication.class, args);
+	}
+}
@@ -0,0 +1,43 @@
+package ru.otus.example.mongodbdemo.changelogs;
+
+import com.github.cloudyrock.mongock.ChangeLog;
+import com.github.cloudyrock.mongock.ChangeSet;
+import com.mongodb.client.MongoDatabase;
+import lombok.val;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.model.Teacher;
+import ru.otus.example.mongodbdemo.repositories.KnowledgeRepository;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+import ru.otus.example.mongodbdemo.repositories.TeacherRepository;
+
+@ChangeLog(order = "001")
+public class InitMongoDBDataChangeLog {
+
+    private Knowledge springDataKnowledge;
+    private Knowledge mongockKnowledge;
+    private Knowledge aggregationApiKnowledge;
+
+    @ChangeSet(order = "000", id = "dropDB", author = "stvort", runAlways = true)
+    public void dropDB(MongoDatabase database){
+        database.drop();
+    }
+
+    @ChangeSet(order = "001", id = "initKnowledges", author = "stvort", runAlways = true)
+    public void initKnowledges(KnowledgeRepository repository){
+        springDataKnowledge = repository.save(new Knowledge("Spring Data"));
+        mongockKnowledge = repository.save(new Knowledge("Mongock"));
+        aggregationApiKnowledge = repository.save(new Knowledge("AggregationApi"));
+    }
+
+    @ChangeSet(order = "002", id = "initStudents", author = "stvort", runAlways = true)
+    public void initStudents(StudentRepository repository){
+        repository.save(new Student("Student #1", springDataKnowledge, mongockKnowledge));
+    }
+
+    @ChangeSet(order = "003", id = "Teacher", author = "stvort", runAlways = true)
+    public void initTeachers(TeacherRepository repository){
+        val teacher = new Teacher("Teacher #1", springDataKnowledge, mongockKnowledge, aggregationApiKnowledge);
+        repository.save(teacher);
+    }
+}
@@ -0,0 +1,24 @@
+package ru.otus.example.mongodbdemo.events;
+
+import lombok.RequiredArgsConstructor;
+import lombok.val;
+import org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener;
+import org.springframework.data.mongodb.core.mapping.event.AfterDeleteEvent;
+import org.springframework.stereotype.Component;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+
+@Component
+@RequiredArgsConstructor
+public class MongoKnowledgeCascadeDeleteEventsListener extends AbstractMongoEventListener<Knowledge> {
+
+    private final StudentRepository studentRepository;
+
+    @Override
+    public void onAfterDelete(AfterDeleteEvent<Knowledge> event) {
+        super.onAfterDelete(event);
+        val source = event.getSource();
+        val id = source.get("_id").toString();
+        studentRepository.removeExperienceArrayElementsById(id);
+    }
+}
@@ -0,0 +1,27 @@
+package ru.otus.example.mongodbdemo.events;
+
+import lombok.RequiredArgsConstructor;
+import lombok.val;
+import org.springframework.data.mongodb.core.mapping.event.AbstractMongoEventListener;
+import org.springframework.data.mongodb.core.mapping.event.BeforeConvertEvent;
+import org.springframework.stereotype.Component;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.repositories.KnowledgeRepository;
+
+import java.util.Objects;
+
+@Component
+@RequiredArgsConstructor
+public class MongoStudentCascadeSaveEventsListener extends AbstractMongoEventListener<Student> {
+
+    private final KnowledgeRepository knowledgeRepository;
+
+    @Override
+    public void onBeforeConvert(BeforeConvertEvent<Student> event) {
+        super.onBeforeConvert(event);
+        val student = event.getSource();
+        if (student.getExperience() != null) {
+            student.getExperience().stream().filter(e -> Objects.isNull(e.getId())).forEach(knowledgeRepository::save);
+        }
+    }
+}
@@ -0,0 +1,21 @@
+package ru.otus.example.mongodbdemo.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+@Document
+public class Knowledge {
+    @Id
+    private String id;
+    private String name;
+
+    public Knowledge(String name) {
+        this.name = name;
+    }
+}
@@ -0,0 +1,29 @@
+package ru.otus.example.mongodbdemo.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.mapping.DBRef;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+import java.util.Arrays;
+import java.util.List;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+@Document
+public class Student {
+    @Id
+    private String id;
+    private String name;
+
+    @DBRef
+    private List<Knowledge> experience;
+
+    public Student(String name, Knowledge... experience) {
+        this.name = name;
+        this.experience = Arrays.asList(experience);
+    }
+}
@@ -0,0 +1,28 @@
+package ru.otus.example.mongodbdemo.model;
+
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.NoArgsConstructor;
+import org.springframework.data.annotation.Id;
+import org.springframework.data.mongodb.core.mapping.Document;
+
+import java.util.Arrays;
+import java.util.List;
+
+@Data
+@NoArgsConstructor
+@AllArgsConstructor
+@Document
+public class Teacher {
+    @Id
+    private String id;
+    private String name;
+
+    private List<Knowledge> experience;
+
+    public Teacher(String name, Knowledge... experience) {
+        this.name = name;
+        this.experience = Arrays.asList(experience);
+
+    }
+}
@@ -0,0 +1,7 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import org.springframework.data.mongodb.repository.MongoRepository;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+
+public interface KnowledgeRepository extends MongoRepository<Knowledge, String> {
+}
@@ -0,0 +1,8 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import org.springframework.data.mongodb.repository.MongoRepository;
+import ru.otus.example.mongodbdemo.model.Student;
+
+
+public interface StudentRepository extends MongoRepository<Student, String>, StudentRepositoryCustom {
+}
@@ -0,0 +1,12 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import ru.otus.example.mongodbdemo.model.Knowledge;
+
+import java.util.List;
+
+public interface StudentRepositoryCustom {
+    List<Knowledge> getStudentExperienceById(String studentId);
+
+    long getExperienceArrayLengthByStudentId(String id);
+    void removeExperienceArrayElementsById(String id);
+}
@@ -0,0 +1,69 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import lombok.Data;
+import lombok.RequiredArgsConstructor;
+import lombok.val;
+import org.bson.Document;
+import org.bson.types.ObjectId;
+import org.springframework.data.mongodb.core.MongoTemplate;
+import org.springframework.data.mongodb.core.aggregation.Aggregation;
+import org.springframework.data.mongodb.core.query.Criteria;
+import org.springframework.data.mongodb.core.query.Query;
+import org.springframework.data.mongodb.core.query.Update;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.utils.RawResultPrinter;
+
+
+import java.util.List;
+
+import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
+import static org.springframework.data.mongodb.core.aggregation.ObjectOperators.ObjectToArray.valueOfToArray;
+import static org.springframework.data.mongodb.core.query.Criteria.where;
+
+@RequiredArgsConstructor
+public class StudentRepositoryCustomImpl implements StudentRepositoryCustom {
+
+    @Data
+    private class ArraySizeProjection {
+        private int size;
+    }
+
+    private final MongoTemplate mongoTemplate;
+    private final RawResultPrinter rawResultPrinter;
+
+    @Override
+    public List<Knowledge> getStudentExperienceById(String studentId) {
+        Aggregation aggregation = newAggregation(
+                match(Criteria.where("id").is(studentId))
+                , unwind("experience")
+                , project().andExclude("_id").and(valueOfToArray("experience")).as("experience_map")
+                , project().and("experience_map").arrayElementAt(1).as("experience_id_map")
+                , project().and("experience_id_map.v").as("experience_id")
+                , lookup("knowledge", "experience_id", "_id", "experience")
+                , project().and("experience._id").as("_id").and("experience.name").as("name")
+        );
+
+        Document rawResults = mongoTemplate.aggregate(aggregation, Student.class, Knowledge.class).getRawResults();
+        rawResultPrinter.prettyPrintRawResult(rawResults);
+        return mongoTemplate.aggregate(aggregation, Student.class, Knowledge.class).getMappedResults();
+    }
+
+    @Override
+    public long getExperienceArrayLengthByStudentId(String studentId) {
+        val aggregation = Aggregation.newAggregation(
+                match(where("id").is(studentId)),
+                project().andExclude("_id").and("experience").size().as("size"));
+
+        val arraySizeProjection = mongoTemplate.aggregate(aggregation, Student.class, ArraySizeProjection.class).getUniqueMappedResult();
+        return arraySizeProjection == null ? 0 : arraySizeProjection.getSize();
+    }
+
+    @Override
+    public void removeExperienceArrayElementsById(String id) {
+        val query = Query.query(Criteria.where("$id").is(new ObjectId(id)));
+        val update = new Update().pull("experience", query);
+        mongoTemplate.updateMulti(new Query(), update, Student.class);
+    }
+
+}
@@ -0,0 +1,7 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import org.springframework.data.mongodb.repository.MongoRepository;
+import ru.otus.example.mongodbdemo.model.Teacher;
+
+public interface TeacherRepository extends MongoRepository<Teacher, String>, TeacherRepositoryCustom {
+}
@@ -0,0 +1,9 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import ru.otus.example.mongodbdemo.model.Knowledge;
+
+import java.util.List;
+
+public interface TeacherRepositoryCustom {
+    List<Knowledge> getTeacherExperienceById(String teacherId);
+}
@@ -0,0 +1,28 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import lombok.RequiredArgsConstructor;
+import lombok.val;
+import org.springframework.data.mongodb.core.MongoTemplate;
+import org.springframework.data.mongodb.core.query.Criteria;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Teacher;
+
+import java.util.List;
+
+import static org.springframework.data.mongodb.core.aggregation.Aggregation.*;
+
+@RequiredArgsConstructor
+public class TeacherRepositoryCustomImpl implements TeacherRepositoryCustom {
+
+    private final MongoTemplate mongoTemplate;
+
+    @Override
+    public List<Knowledge> getTeacherExperienceById(String teacherId) {
+        val aggregation = newAggregation(
+                match(Criteria.where("id").is(teacherId))
+                , unwind("experience")
+                , project().andExclude("_id").and("experience.id").as("_id").and("experience.name").as("name")
+        );
+        return mongoTemplate.aggregate(aggregation, Teacher.class, Knowledge.class).getMappedResults();
+    }
+}
@@ -0,0 +1,8 @@
+package ru.otus.example.mongodbdemo.utils;
+
+import org.bson.Document;
+
+public interface RawResultPrinter {
+    @SuppressWarnings("unchecked")
+    void prettyPrintRawResult(Document document);
+}
@@ -0,0 +1,18 @@
+package ru.otus.example.mongodbdemo.utils;
+
+import org.bson.Document;
+import org.springframework.stereotype.Component;
+
+import java.util.List;
+import java.util.stream.Collectors;
+
+@Component
+public class RawResultPrinterImpl implements RawResultPrinter {
+    @SuppressWarnings("unchecked")
+    @Override
+    public void prettyPrintRawResult(Document document) {
+        List<Document> results = (List<Document>) document.get("results");
+        String resultsAsString = results.stream().map(Document::toString).collect(Collectors.joining("\n"));
+        System.out.println(resultsAsString);
+    }
+}
@@ -0,0 +1,9 @@
+spring:
+  data:
+    mongodb:
+      uri: mongodb://localhost
+      port: 27017
+      database: awesomeMongo
+logging:
+  level:
+    root: ERROR
@@ -0,0 +1,14 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import org.springframework.boot.context.properties.EnableConfigurationProperties;
+import org.springframework.boot.test.autoconfigure.data.mongo.DataMongoTest;
+import org.springframework.context.annotation.ComponentScan;
+import org.springframework.context.annotation.Import;
+import ru.otus.example.mongodbdemo.utils.RawResultPrinterImpl;
+
+@DataMongoTest
+@EnableConfigurationProperties
+@ComponentScan({"ru.otus.example.mongodbdemo.config", "ru.otus.example.mongodbdemo.repositories"})
+@Import(RawResultPrinterImpl.class)
+public abstract class AbstractRepositoryTest {
+}
@@ -0,0 +1,29 @@
+package ru.otus.example.mongodbdemo.repositories;
+
+import lombok.val;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@DisplayName("TeacherRepository должен ")
+class TeacherRepositoryTest extends AbstractRepositoryTest {
+
+    @Autowired
+    private TeacherRepository teacherRepository;
+
+    @DisplayName(" возвращать корректный список знаний преподавателя")
+    @Test
+    void shouldReturnCorrectKnowledgeList(){
+        val teachers = teacherRepository.findAll();
+        val teacher = teachers.get(0);
+        val experience = teacher.getExperience();
+        assertThat(experience).isNotNull().hasSize(3);
+
+        val actualExperience = teacherRepository.getTeacherExperienceById(teacher.getId());
+        assertThat(actualExperience).containsExactlyInAnyOrder(experience.toArray(new Knowledge[0]));
+
+    }
+}
@@ -0,0 +1,58 @@
+package ru.otus.example.mongodbdemo.repositories.plain;
+
+import lombok.val;
+import org.assertj.core.api.AbstractObjectAssert;
+import org.assertj.core.api.AbstractOptionalAssert;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.repositories.AbstractRepositoryTest;
+import ru.otus.example.mongodbdemo.repositories.KnowledgeRepository;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+
+import java.util.List;
+import java.util.function.Function;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+
+@DisplayName("KnowledgeRepository при отсутствии listener-ов в контексте ")
+class KnowledgeRepositoryWithoutListenerTest extends AbstractRepositoryTest {
+
+    @Autowired
+    private KnowledgeRepository knowledgeRepository;
+
+    @Autowired
+    private StudentRepository studentRepository;
+
+    @DisplayName("при удалении Knowledge не должен удалять его из опыта студента")
+    @Test
+    void shouldLeaveKnowledgeInStudentExperienceWhenRemovingKnowledge() {
+
+        // Загрузка студента и его первого знания
+        val students = studentRepository.findAll();
+        val student = students.get(0);
+        val experience = student.getExperience();
+        val firstKnowledge = experience.get(0);
+
+        // Удаление знания из коллекции знаний
+        knowledgeRepository.delete(firstKnowledge);
+
+        // Загружаем студента заново и проверяем, что знание действительно удалено (размер стал меньше на 1)
+        val expectedExperienceArrayLength = experience.size() - 1;
+        val actualStudentOptional = studentRepository.findById(student.getId());
+        assertThat(actualStudentOptional)
+                .isNotEmpty().get()
+                .matches(s -> s.getExperience() != null && s.getExperience().size() == expectedExperienceArrayLength);
+
+
+        // Загружаем размер массива с помощью аггрегаций и проверяем, что на самом деле размер массива в БД не изменился
+        val actualExperienceArrayLength = studentRepository.getExperienceArrayLengthByStudentId(student.getId());
+        assertThat(actualExperienceArrayLength).isNotEqualTo(expectedExperienceArrayLength);
+
+
+
+    }
+}
@@ -0,0 +1,27 @@
+package ru.otus.example.mongodbdemo.repositories.plain;
+
+import lombok.val;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.data.mapping.MappingException;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.repositories.AbstractRepositoryTest;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+
+import static org.assertj.core.api.Assertions.*;
+
+@DisplayName("StudentRepository при отсутствии listener-ов в контексте ")
+class StudentRepositoryWithoutListenerTest extends AbstractRepositoryTest {
+
+    @Autowired
+    private StudentRepository studentRepository;
+
+    @DisplayName("должен кидать MappingException во время сохранения студента с отсутствующими в БД знаниями")
+    @Test
+    void shouldThrowMappingExceptionWhenSaveStudentWithNewKnowledge(){
+        val student = new Student("Student #2", new Knowledge("Knowledge #3"));
+        assertThatThrownBy(() -> studentRepository.save(student)).isInstanceOf(MappingException.class);
+    }
+}
@@ -0,0 +1,49 @@
+package ru.otus.example.mongodbdemo.repositories.withlisteners;
+
+import lombok.val;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.ComponentScan;
+import ru.otus.example.mongodbdemo.repositories.AbstractRepositoryTest;
+import ru.otus.example.mongodbdemo.repositories.KnowledgeRepository;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@DisplayName("KnowledgeRepository при наличии listener-ов в контексте ")
+@ComponentScan("ru.otus.example.mongodbdemo.events")
+class KnowledgeRepositoryWithListenerTest extends AbstractRepositoryTest {
+
+    @Autowired
+    private KnowledgeRepository knowledgeRepository;
+
+    @Autowired
+    private StudentRepository studentRepository;
+
+    @DisplayName("при удалении Knowledge должен удалить его из опыта студента")
+    @Test
+    void shouldRemoveKnowledgeFromStudentExperienceWhenRemovingKnowledge() {
+
+        // Загрузка студента и его первого знания
+        val students = studentRepository.findAll();
+        val student = students.get(0);
+        val experience = student.getExperience();
+        val firstKnowledge = experience.get(0);
+
+        // Удаление знания из коллекции знаний
+        knowledgeRepository.delete(firstKnowledge);
+
+        // Загружаем студента заново и проверяем, что знание действительно удалено (размер стал меньше на 1)
+        val expectedExperienceArrayLength = experience.size() - 1;
+        val actualStudentOptional = studentRepository.findById(student.getId());
+        assertThat(actualStudentOptional)
+                .isNotEmpty().get()
+                .matches(s -> s.getExperience() != null && s.getExperience().size() == expectedExperienceArrayLength);
+
+        // Загружаем размер массива с помощью аггрегаций и проверяем, что размер массива в БД тоже изменился
+        val actualExperienceArrayLength = studentRepository.getExperienceArrayLengthByStudentId(student.getId());
+        assertThat(actualExperienceArrayLength).isEqualTo(expectedExperienceArrayLength);
+
+    }
+}
@@ -0,0 +1,41 @@
+package ru.otus.example.mongodbdemo.repositories.withlisteners;
+
+import lombok.val;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.Test;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.context.annotation.ComponentScan;
+import ru.otus.example.mongodbdemo.model.Knowledge;
+import ru.otus.example.mongodbdemo.model.Student;
+import ru.otus.example.mongodbdemo.repositories.AbstractRepositoryTest;
+import ru.otus.example.mongodbdemo.repositories.StudentRepository;
+
+import java.util.List;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+@DisplayName("StudentRepository при наличии listener-ов в контексте ")
+@ComponentScan("ru.otus.example.mongodbdemo.events")
+class StudentRepositoryWithListenersTest extends AbstractRepositoryTest {
+
+    @Autowired
+    private StudentRepository studentRepository;
+
+    @DisplayName("должен корректно сохранять студента с отсутствующими в БД знаниями")
+    @Test
+    void shouldCorrectSaveStudentWithNewKnowledge(){
+        val student = new Student("Student #2", new Knowledge("Knowledge #3"));
+        val actual = studentRepository.save(student);
+        assertThat(actual.getId()).isNotNull();
+        assertThat(actual.getName()).isEqualTo(student.getName());
+    }
+
+    @DisplayName("должен возвращать корректный список знаний студента")
+    @Test
+    void shouldReturnCorrectStudentKnowledgeList(){
+        val student = studentRepository.findAll().get(0);
+        List<Knowledge> knowledgeList = studentRepository.getStudentExperienceById(student.getId());
+        assertThat(knowledgeList).containsExactlyInAnyOrderElementsOf(student.getExperience());
+    }
+
+}
@@ -0,0 +1,18 @@
+spring:
+  data:
+    mongodb:
+      port: 0
+      database: test
+      #uri: mongodb://localhost
+      #port: 27017
+      #database: awesomeMongo
+
+
+
+  mongock:
+    change-logs-scan-package:
+      - ru.otus.example.mongodbdemo.changelogs
+
+logging:
+  level:
+    root: ERROR
@@ -6,7 +6,7 @@
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
-        <version>2.2.1.RELEASE</version>
+        <version>2.2.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

@@ -20,7 +20,7 @@
        <java.version>11</java.version>
        <maven.compiler.sourcre>11</maven.compiler.sourcre>
        <maven.compiler.target>11</maven.compiler.target>
-        <mongock.version>2.0.2</mongock.version>
+        <mongock.version>3.2.8</mongock.version>
    </properties>

    <dependencies>