Added application layer and blockchain implementation

src/main/java/com/rviewer/skeletons/application/adapter/CartController.java

@@ -1,12 +1,12 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.adapter;
+package com.rviewer.skeletons.application.adapter;
 
+import com.rviewer.skeletons.application.exception.CartAlreadyExistsException;
+import com.rviewer.skeletons.application.exception.CartNotFoundException;
 import com.rviewer.skeletons.domain.model.Cart;
 import com.rviewer.skeletons.domain.model.Item;
 import com.rviewer.skeletons.domain.service.CartService;
-import com.rviewer.skeletons.infrastructure.inbound.api.exception.CartAlreadyExistsException;
-import com.rviewer.skeletons.infrastructure.inbound.api.exception.CartNotFoundException;
-import com.rviewer.skeletons.infrastructure.inbound.api.request.CreateCartReq;
-import com.rviewer.skeletons.infrastructure.inbound.api.request.UpdateCartReq;
+import com.rviewer.skeletons.application.request.CreateCartReq;
+import com.rviewer.skeletons.application.request.UpdateCartReq;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.DeleteMapping;

src/main/java/com/rviewer/skeletons/application/exception/CartAlreadyExistsException.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.exception;
+package com.rviewer.skeletons.application.exception;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.ResponseStatus;

src/main/java/com/rviewer/skeletons/application/exception/CartNotFoundException.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.exception;
+package com.rviewer.skeletons.application.exception;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.web.bind.annotation.ResponseStatus;

src/main/java/com/rviewer/skeletons/application/exception/ControllerExceptionHandler.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.exception;
+package com.rviewer.skeletons.application.exception;
 
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;

src/main/java/com/rviewer/skeletons/application/request/CreateCartReq.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.request;
+package com.rviewer.skeletons.application.request;
 
 import com.rviewer.skeletons.domain.model.Item;
 import lombok.Getter;

src/main/java/com/rviewer/skeletons/application/request/UpdateCartReq.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.inbound.api.request;
+package com.rviewer.skeletons.application.request;
 
 import com.rviewer.skeletons.domain.model.Item;
 import lombok.Getter;

src/main/java/com/rviewer/skeletons/domain/exception/HashGenerationException.java

@@ -0,0 +1,7 @@
+package com.rviewer.skeletons.domain.exception;
+
+public class HashGenerationException extends RuntimeException {
+    public HashGenerationException(Throwable cause) {
+        super("Unable generate hash: " + cause);
+    }
+}

src/main/java/com/rviewer/skeletons/domain/model/Block.java

@@ -0,0 +1,52 @@
+package com.rviewer.skeletons.domain.model;
+
+import com.rviewer.skeletons.domain.exception.HashGenerationException;
+import lombok.AllArgsConstructor;
+import lombok.Data;
+import lombok.With;
+
+import java.nio.charset.StandardCharsets;
+import java.security.MessageDigest;
+import java.time.LocalDateTime;
+import java.util.Random;
+
+@Data
+@AllArgsConstructor
+@With
+public class Block {
+    private LocalDateTime timestamp;
+    private String lasthash;
+    private String data;
+    private Integer nonce;
+    private String hash;
+
+    public Block() {
+        this.timestamp = LocalDateTime.now();
+        this.nonce = new Random().nextInt();
+        this.hash = generateHashFromBlock(this);
+    }
+
+    public static Block getGenesisBlock() {
+        return new Block().withLasthash("");
+    }
+
+    static String generateHashFromBlock(final Block block) throws HashGenerationException {
+        try {
+            final var digest = MessageDigest.getInstance("SHA-256");
+            final byte[] hash = digest.digest(block.getHashData().getBytes(StandardCharsets.UTF_8));
+            final var hexString = new StringBuilder();
+            for (final byte elem : hash) {
+                final var hex = Integer.toHexString(0xff & elem);
+                if (hex.length() == 1) hexString.append('0');
+                hexString.append(hex);
+            }
+            return hexString.toString();
+        } catch (final Exception e) {
+            throw new HashGenerationException(e);
+        }
+    }
+
+    private String getHashData() {
+        return timestamp + lasthash + data + nonce;
+    }
+}

src/main/java/com/rviewer/skeletons/domain/model/Blockchain.java

@@ -0,0 +1,28 @@
+package com.rviewer.skeletons.domain.model;
+
+import org.springframework.stereotype.Component;
+
+import java.util.LinkedList;
+import java.util.List;
+
+@Component
+public class Blockchain {
+    private final LinkedList<Block> blockchainList = new LinkedList<>();
+
+    public LinkedList<Block> getBlockchainList() {
+        return blockchainList;
+    }
+
+    public Block addBlock(Block block) {
+        blockchainList.add(block);
+        return blockchainList.getLast();
+    }
+
+    public Boolean replace(List<Block> blockchainList) {
+        return true;
+    }
+
+    public Boolean isValid(List<Block> blockchainList) {
+        return true;
+    }
+}

src/main/java/com/rviewer/skeletons/domain/ports/secondary/CartDatabasePort.java

@@ -4,7 +4,7 @@ import com.rviewer.skeletons.domain.model.Cart;
 
 import java.util.Optional;
 
-public interface DatabasePort {
+public interface CartDatabasePort {
 
     Optional<Cart> get(String id);
     void save(Cart cart);

src/main/java/com/rviewer/skeletons/domain/service/CartService.java

@@ -1,8 +1,10 @@
 package com.rviewer.skeletons.domain.service;
 
+import com.rviewer.skeletons.domain.model.Block;
+import com.rviewer.skeletons.domain.model.Blockchain;
 import com.rviewer.skeletons.domain.model.Cart;
 import com.rviewer.skeletons.domain.ports.primary.CartServicePort;
-import com.rviewer.skeletons.domain.ports.secondary.DatabasePort;
+import com.rviewer.skeletons.domain.ports.secondary.CartDatabasePort;
 import org.springframework.stereotype.Component;
 
 import javax.transaction.Transactional;
@@ -11,24 +13,34 @@ import java.util.Optional;
 @Component
 @Transactional
 public class CartService implements CartServicePort {
-    private final DatabasePort databasePort;
+    private final CartDatabasePort cartDatabasePort;
+    private final Blockchain blockchain;
 
-    public CartService(DatabasePort databasePort) {
-        this.databasePort = databasePort;
+    public CartService(CartDatabasePort cartDatabasePort, Blockchain blockchain) {
+        this.cartDatabasePort = cartDatabasePort;
+        this.blockchain = blockchain;
     }
 
     @Override
     public Optional<Cart> get(String id) {
-        return databasePort.get(id);
+        return cartDatabasePort.get(id);
     }
 
     @Override
     public void save(Cart cart) {
-        databasePort.save(cart);
+        cartDatabasePort.save(cart);
+        if (blockchain.getBlockchainList().isEmpty()) {
+            blockchain.addBlock(Block.getGenesisBlock().withData(cart.toString()));
+        } else {
+            blockchain.addBlock(new Block().withData(cart.toString())
+                    .withLasthash(blockchain.getBlockchainList().getLast().getHash()));
+        }
     }
 
     @Override
     public void delete(String id) {
-        databasePort.delete(id);
+        cartDatabasePort.delete(id);
+        blockchain.addBlock(new Block().withData("deleted cart with id:" + id)
+                .withLasthash(blockchain.getBlockchainList().getLast().getHash()));
     }
 }

src/main/java/com/rviewer/skeletons/infrastructure/database/adapter/CartDatabaseAdapter.java

@@ -1,20 +1,20 @@
-package com.rviewer.skeletons.infrastructure.outbound.database.adapter;
+package com.rviewer.skeletons.infrastructure.database.adapter;
 
 import com.rviewer.skeletons.domain.model.Cart;
-import com.rviewer.skeletons.domain.ports.secondary.DatabasePort;
-import com.rviewer.skeletons.infrastructure.outbound.database.repository.PostgresCartRepository;
-import com.rviewer.skeletons.infrastructure.outbound.database.dto.PostgresCart;
+import com.rviewer.skeletons.domain.ports.secondary.CartDatabasePort;
+import com.rviewer.skeletons.infrastructure.database.dto.PostgresCart;
+import com.rviewer.skeletons.infrastructure.database.repository.PostgresCartRepository;
 import org.springframework.stereotype.Component;
 
 import java.util.Optional;
 import java.util.UUID;
 
 @Component
-public class PostgresAdapter implements DatabasePort {
+public class CartDatabaseAdapter implements CartDatabasePort {
 
     private final PostgresCartRepository postgresCartRepository;
 
-    public PostgresAdapter(PostgresCartRepository postgresCartRepository) {
+    public CartDatabaseAdapter(PostgresCartRepository postgresCartRepository) {
         this.postgresCartRepository = postgresCartRepository;
     }
 

src/main/java/com/rviewer/skeletons/infrastructure/database/dto/PostgresCart.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.outbound.database.dto;
+package com.rviewer.skeletons.infrastructure.database.dto;
 
 import com.rviewer.skeletons.domain.model.Cart;
 import lombok.AllArgsConstructor;

src/main/java/com/rviewer/skeletons/infrastructure/database/dto/PostgresItem.java

@@ -1,4 +1,4 @@
-package com.rviewer.skeletons.infrastructure.outbound.database.dto;
+package com.rviewer.skeletons.infrastructure.database.dto;
 
 import com.rviewer.skeletons.domain.model.Item;
 import lombok.AllArgsConstructor;

src/main/java/com/rviewer/skeletons/infrastructure/database/repository/PostgresCartRepository.java

@@ -1,6 +1,6 @@
-package com.rviewer.skeletons.infrastructure.outbound.database.repository;
+package com.rviewer.skeletons.infrastructure.database.repository;
 
-import com.rviewer.skeletons.infrastructure.outbound.database.dto.PostgresCart;
+import com.rviewer.skeletons.infrastructure.database.dto.PostgresCart;
 import org.springframework.data.repository.CrudRepository;
 import org.springframework.stereotype.Repository;
 

src/main/resources/application.properties

@@ -2,7 +2,7 @@ server.port=8080
 application.title=Cartfidential
 application.version=1.0.0
 
-spring.datasource.initialization-mode=always
+spring.sql.init.mode=always
 spring.datasource.username = rv_user
 spring.datasource.password = rv_password
 spring.datasource.driverClassName = org.postgresql.Driver

src/test/java/com/rviewer/skeletons/infrastructure/inbound/api/adapter/CartControllerTest.java

@@ -4,8 +4,8 @@ import com.fasterxml.jackson.databind.ObjectMapper;
 import com.rviewer.skeletons.domain.model.Cart;
 import com.rviewer.skeletons.domain.model.Item;
 import com.rviewer.skeletons.domain.service.CartService;
-import com.rviewer.skeletons.infrastructure.inbound.api.exception.CartAlreadyExistsException;
-import com.rviewer.skeletons.infrastructure.inbound.api.exception.CartNotFoundException;
+import com.rviewer.skeletons.application.exception.CartAlreadyExistsException;
+import com.rviewer.skeletons.application.exception.CartNotFoundException;
 import org.junit.jupiter.api.Test;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.boot.test.autoconfigure.web.servlet.AutoConfigureMockMvc;
@@ -21,7 +21,7 @@ import java.util.List;
 import java.util.Optional;
 import java.util.UUID;
 
-import static com.rviewer.skeletons.infrastructure.inbound.api.exception.ControllerExceptionHandler.INVALID_BODY;
+import static com.rviewer.skeletons.application.exception.ControllerExceptionHandler.INVALID_BODY;
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.when;

src/test/java/com/rviewer/skeletons/infrastructure/outbound/adapter/CartDatabaseAdapterTest.java

@@ -2,9 +2,9 @@ package com.rviewer.skeletons.infrastructure.outbound.adapter;
 
 import com.rviewer.skeletons.domain.model.Cart;
 import com.rviewer.skeletons.domain.model.Item;
-import com.rviewer.skeletons.infrastructure.outbound.database.adapter.PostgresAdapter;
-import com.rviewer.skeletons.infrastructure.outbound.database.dto.PostgresCart;
-import com.rviewer.skeletons.infrastructure.outbound.database.repository.PostgresCartRepository;
+import com.rviewer.skeletons.infrastructure.database.adapter.CartDatabaseAdapter;
+import com.rviewer.skeletons.infrastructure.database.dto.PostgresCart;
+import com.rviewer.skeletons.infrastructure.database.repository.PostgresCartRepository;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 import org.mockito.ArgumentCaptor;
@@ -23,16 +23,16 @@ import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.when;
 
 @SpringBootTest
-class PostgresAdapterTest {
+class CartDatabaseAdapterTest {
 
     @Autowired
-    private PostgresAdapter postgresAdapter;
+    private CartDatabaseAdapter cartDatabaseAdapter;
     @Mock
     private PostgresCartRepository postgresCartRepository;
 
     @BeforeEach
     void init() {
-        postgresAdapter = new PostgresAdapter(postgresCartRepository);
+        cartDatabaseAdapter = new CartDatabaseAdapter(postgresCartRepository);
     }
 
     @Test
@@ -43,7 +43,7 @@ class PostgresAdapterTest {
 
         when(postgresCartRepository.findById(id)).thenReturn(Optional.ofNullable(PostgresCart.fromDomain(expectedCart)));
 
-        Optional<Cart> result = postgresAdapter.get(id.toString());
+        Optional<Cart> result = cartDatabaseAdapter.get(id.toString());
         assertThat(Optional.of(result)).hasValue(Optional.of(expectedCart));
     }
 
@@ -53,7 +53,7 @@ class PostgresAdapterTest {
         Item item = new Item(UUID.randomUUID(), "item", 1, 100F);
         Cart newCart = new Cart(id, List.of(item));
 
-        postgresAdapter.save(newCart);
+        cartDatabaseAdapter.save(newCart);
 
         ArgumentCaptor<PostgresCart> captor = ArgumentCaptor.forClass(PostgresCart.class);
         verify(postgresCartRepository).save(captor.capture());
@@ -68,7 +68,7 @@ class PostgresAdapterTest {
 
         when(postgresCartRepository.findById(id)).thenReturn(Optional.ofNullable(PostgresCart.fromDomain(cartToDelete)));
 
-        postgresAdapter.delete(cartToDelete.getId().toString());
+        cartDatabaseAdapter.delete(cartToDelete.getId().toString());
 
         verify(postgresCartRepository, times(1)).deleteById(cartToDelete.getId());
     }