[BOOK-79] feat: infra - BookRepository 기능개발 (#15)

Author: minwoo1999

infra/src/main/kotlin/org/yapp/infra/book/repository/JpaBookRepository.kt

@@ -0,0 +1,12 @@
+package org.yapp.infra.book.repository
+
+import org.springframework.data.jpa.repository.JpaRepository
+import org.yapp.infra.book.entity.BookEntity
+
+/**
+ * JPA repository for BookEntity.
+ */
+interface JpaBookRepository : JpaRepository<BookEntity, String> {
+
+    fun findByIsbn(isbn: String): BookEntity?
+}

infra/src/main/kotlin/org/yapp/infra/book/repository/impl/BookRepositoryImpl.kt

@@ -0,0 +1,23 @@
+package org.yapp.infra.book.repository.impl
+
+import org.springframework.stereotype.Repository
+import org.yapp.domain.book.Book
+import org.yapp.domain.book.BookRepository
+import org.yapp.infra.book.entity.BookEntity
+import org.yapp.infra.book.repository.JpaBookRepository
+
+@Repository
+class BookRepositoryImpl(
+    private val jpaBookRepository: JpaBookRepository
+) : BookRepository {
+
+    override fun findByIsbn(isbn: String): Book? {
+        return jpaBookRepository.findByIsbn(isbn)?.toDomain()
+    }
+
+    override fun save(book: Book): Book {
+        val bookEntity = BookEntity.fromDomain(book)
+        val savedEntity = jpaBookRepository.save(bookEntity)
+        return savedEntity.toDomain()
+    }
+}