fix: using uuid

Author: xmlking

docs/awesome/awesome-gradle.md

@@ -0,0 +1,3 @@
+Awesome Gradle
+
+A curated list of awesome Gradle build tool tips and blogs.

docs/awesome/awesome-spring.md

@@ -0,0 +1,14 @@
+Awesome Spring
+
+A curated list of awesome Spring Framework libraries and blogs.
+
+## Architecture 
+- [Hexagonal Architecture on Spring Boot](https://jivimberg.io/blog/2020/02/01/hexagonal-architecture-on-spring-boot/)
+- [Using UUID on Spring Data JPA Entities](https://jivimberg.io/blog/2018/11/05/using-uuid-on-spring-data-jpa-entities/)
+
+### Event Driven Architecture
+- [How Wix manages Schemas for Kafka (and gRPC) used by 2000 microservices](https://medium.com/wix-engineering/how-wix-manages-schemas-for-kafka-and-grpc-used-by-2000-microservices-2117416ea17b)
+- [Spring Cloud Data Flow: The Core Components](https://www.zaloni.com/resources/blogs/the-core-components-of-spring-cloud-data-flow/)
+
+## Testing
+- [Mockk All the Things](https://jivimberg.io/blog/2019/05/09/mockk-features-rundown/)

docs/concepts/testing.md

@@ -1,3 +1,4 @@
 # Testing
 
 - [Testing Koin applications with Kotest](https://dev.to/kerooker/testing-koin-applications-with-kotlintest-1iip)
+- [Mockk All the Things](https://jivimberg.io/blog/2019/05/09/mockk-features-rundown/)

gradle/libs.versions.toml

@@ -188,6 +188,7 @@ spring-boot-starter-security = { module = "org.springframework.boot:spring-boot-
 spring-boot-starter-oauth2-resource-server = { module = "org.springframework.boot:spring-boot-starter-oauth2-resource-server" }
 spring-boot-reactor-kotlin-extensions = { module = "io.projectreactor.kotlin:reactor-kotlin-extensions" }
 spring-boot-reactor-kafka = { module = "io.projectreactor.kafka:reactor-kafka" }
+spring-boot-kafka = { module = "org.springframework.kafka:spring-kafka" }
 
 spring-boot-starter-graphql = { module = "org.springframework.boot:spring-boot-starter-graphql" }
 spring-boot-starter-validation  = { module = "org.springframework.boot:spring-boot-starter-validation" }
@@ -354,6 +355,7 @@ spring-boot-mockk-test = { module = "com.ninja-squad:springmockk", version.ref =
 spring-boot-reactor-test = { module = "io.projectreactor:reactor-test" }
 spring-boot-graphql-test = { module = "org.springframework.graphql:spring-graphql-test" }
 spring-boot-security-test = { module = "org.springframework.security:spring-security-test" }
+spring-boot-kafka-test = { module = "org.springframework.kafka:spring-kafka-test" }
 turbine-test = { module = "app.cash.turbine:turbine", version.ref = "turbine" }
 junit4-test = { module = "junit:junit", version.ref = "junit4" }
 spring-boot-flyway-test = { module = "org.flywaydb.flyway-test-extensions:flyway-spring-test", version.ref = "flywayTest" }

services/spring-graphql-r2dbc/src/main/kotlin/micro/apps/service/domain/book/BookService.kt

@@ -14,11 +14,11 @@ class BookService(private val bookRepository: BookRepository, private val author
     // @Transactional
     suspend fun createBook(input: CreateBookInput): Book {
         val book = bookRepository.save(
-            Book(/*id = UuidCreator.getTimeOrderedEpoch(),*/ title = input.title, pages = input.pages, category = input.category)
+            Book(title = input.title, pages = input.pages, category = input.category)
         )
         logger.atDebug().addKeyValue("book", book).log("saved book")
         authorRepository.save(
-            Author(/*id = UuidCreator.getTimeOrderedEpoch(),*/ name = input.author, age = 0, bookId = book.id)
+            Author( name = input.author, age = 0, bookId = book.id)
         )
         return book
     }

services/spring-graphql-r2dbc/src/main/kotlin/micro/apps/service/domain/book/models.kt

@@ -1,5 +1,6 @@
 package micro.apps.service.domain.book
 
+import com.github.f4b6a3.uuid.UuidCreator
 import org.springframework.data.annotation.CreatedBy
 import org.springframework.data.annotation.CreatedDate
 import org.springframework.data.annotation.Id
@@ -13,7 +14,14 @@ import java.util.UUID
 
 @Table("books")
 data class Book(
-    @Id val id: UUID? = null,
+    // setting id = null, lets database set UUID if supported.
+    // @Id val id: UUID? = null,
+    /**
+     * Having application generated ids means the id is known even before the entity is persisted.
+     * This lets us model our entities as immutable objects and we avoid having to handle null values on the id
+     * https://jivimberg.io/blog/2018/11/05/using-uuid-on-spring-data-jpa-entities/
+     */
+    @Id val id: UUID = UuidCreator.getTimeOrderedEpoch(),
     val title: String,
     val pages: Int,
     val category: Category,
@@ -42,7 +50,7 @@ enum class Category {
 
 @Table("authors")
 data class Author(
-    @Id val id: UUID? = null,
+    @Id val id: UUID = UuidCreator.getTimeOrderedEpoch(),
     val name: String,
     val age: Int?,
     @Column("book_id")

services/spring-graphql-r2dbc/src/main/resources/graphql/book.graphqls

@@ -1,5 +1,7 @@
 extend type Query {
     bookById(id: UUID!): Book
+    bookByTitle(title: String!): Book
+    books : [Book!]
 }
 
 extend type Mutation {