Merge pull request #28 from sankeyraut/v2

feat: v2 architecture

.gitignore

@@ -1,8 +1,5 @@
-unicorn_properties/samconfig.toml
 unicorn_properties/PropertyFunctions/target/*
-unicorn_contracts/samconfig.toml
 unicorn_contracts/ContractsFunction/target/**
-unicorn_web/samconfig.toml
 unicorn_web/PropertyFunctions/target/**
 **/.aws-sam/
 .DS_Store**

unicorn_contracts/ContractsFunction/pom.xml

@@ -174,6 +174,14 @@
           </execution>
         </executions>
       </plugin>
+        <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-compiler-plugin</artifactId>
+            <configuration>
+                <source>16</source>
+                <target>16</target>
+            </configuration>
+        </plugin>
     </plugins>
   </build>
 </project>

unicorn_contracts/ContractsFunction/src/main/java/contracts/ContractEventHandler.java

@@ -0,0 +1,150 @@
+package contracts;
+
+import com.amazonaws.services.lambda.runtime.Context;
+import com.amazonaws.services.lambda.runtime.RequestHandler;
+
+import com.amazonaws.services.lambda.runtime.events.SQSEvent;
+import com.amazonaws.services.lambda.runtime.events.SQSEvent.SQSMessage;
+
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import contracts.utils.Contract;
+
+import contracts.utils.ContractStatusEnum;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import software.amazon.awssdk.services.dynamodb.DynamoDbClient;
+import software.amazon.awssdk.services.dynamodb.model.AttributeValue;
+import software.amazon.awssdk.services.dynamodb.model.ConditionalCheckFailedException;
+import software.amazon.awssdk.services.dynamodb.model.PutItemRequest;
+import software.amazon.awssdk.services.dynamodb.model.ResourceNotFoundException;
+import software.amazon.awssdk.services.dynamodb.model.UpdateItemRequest;
+import software.amazon.cloudwatchlogs.emf.logger.MetricsLogger;
+import software.amazon.lambda.powertools.metrics.MetricsUtils;
+import software.amazon.lambda.powertools.tracing.Tracing;
+
+import java.util.Date;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.UUID;
+
+public class ContractEventHandler implements RequestHandler<SQSEvent, Void> {
+
+    // Initialise environment variables
+    private static String DDB_TABLE = System.getenv("DYNAMODB_TABLE");
+    ObjectMapper objectMapper = new ObjectMapper();
+
+    DynamoDbClient dynamodbClient = DynamoDbClient.builder()
+            .build();
+
+    Logger logger = LogManager.getLogger();
+    MetricsLogger metricsLogger = MetricsUtils.metricsLogger();
+
+    @Override
+    public Void handleRequest(SQSEvent event, Context context) {
+
+        for (SQSMessage msg : event.getRecords()) {
+            // cehck in message attributes about the http method (HttpMethod)
+            logger.debug(msg.toString());
+            String httpMethod = msg.getMessageAttributes().get("HttpMethod").getStringValue();
+            if ("POST".equalsIgnoreCase(httpMethod)) {
+                try {
+                    createContract(msg.getBody());
+                    logger.debug("Contract Saved");
+                } catch (JsonProcessingException jsonException) {
+                    logger.error("Unknown Exception occoured: " + jsonException.getMessage());
+                    logger.fatal(jsonException);
+                    jsonException.printStackTrace();
+                }
+
+            } else if ("PUT".equalsIgnoreCase(httpMethod)) {
+                try {
+                    // update the event
+                    updateContract(msg.getBody());
+                } catch (JsonProcessingException jsonException) {
+                    logger.error("Unknown Exception occoured: " + jsonException.getMessage());
+                    logger.fatal(jsonException);
+                    jsonException.printStackTrace();
+                }
+
+            }
+
+        }
+        return null;
+    }
+
+    @Tracing
+    private void createContract(String strContract) throws JsonProcessingException {
+        String contractId = UUID.randomUUID().toString();
+        Long createDate = new Date().getTime();
+        Contract contract = objectMapper.readValue(strContract, Contract.class);
+
+        Map<String, AttributeValue> expressionValues = new HashMap<>();
+        expressionValues.put(":cancelled", AttributeValue.builder().s(ContractStatusEnum.CANCELLED.name()).build());
+        expressionValues.put(":closed", AttributeValue.builder().s(ContractStatusEnum.CLOSED.name()).build());
+        expressionValues.put(":expired", AttributeValue.builder().s(ContractStatusEnum.EXPIRED.name()).build());
+
+        HashMap<String, AttributeValue> itemValues = new HashMap<>();
+        itemValues.put("property_id", AttributeValue.builder().s(contract.getPropertyId()).build());
+        itemValues.put("seller_name", AttributeValue.builder().s(contract.getSellerName()).build());
+        itemValues.put("contract_created",
+                AttributeValue.builder().n(createDate.toString()).build());
+        itemValues.put("contract_last_modified_on",
+                AttributeValue.builder().n(createDate.toString()).build());
+        itemValues.put("contract_id", AttributeValue.builder().s(contractId).build());
+        itemValues.put("contract_status", AttributeValue.builder().s(ContractStatusEnum.DRAFT.name()).build());
+        itemValues.put("address",
+                AttributeValue.builder().s(objectMapper.writeValueAsString(contract.getAddress())).build());
+        PutItemRequest putItemRequest = PutItemRequest.builder().tableName(DDB_TABLE)
+                .item(itemValues)
+                .conditionExpression(
+                        "attribute_not_exists(property_id) OR contract_status IN (:cancelled , :closed, :expired)")
+                .expressionAttributeValues(expressionValues)
+                .build();
+        try {
+            dynamodbClient.putItem(putItemRequest);
+        } catch (ConditionalCheckFailedException conditionalCheckFailedException) {
+            logger.error("Unable to create contract for Property '" + contract.getPropertyId()
+                    + "'.There already is a contract for this property in status " + ContractStatusEnum.DRAFT + " or "
+                    + ContractStatusEnum.APPROVED);
+        }
+    }
+
+    @Tracing
+    private void updateContract(String strContract) throws JsonProcessingException {
+        Contract contract = objectMapper.readValue(strContract, Contract.class);
+        logger.info("Property ID is : " + contract.getPropertyId());
+        HashMap<String, AttributeValue> itemKey = new HashMap<>();
+
+        itemKey.put("property_id", AttributeValue.builder().s(contract.getPropertyId()).build());
+
+        Map<String, AttributeValue> expressionAttributeValues = new HashMap<>();
+        expressionAttributeValues.put(":draft", AttributeValue.builder().s(ContractStatusEnum.DRAFT.name()).build());
+        expressionAttributeValues.put(":t", AttributeValue.builder().s(ContractStatusEnum.APPROVED.name()).build());
+        expressionAttributeValues.put(":m", AttributeValue.builder().s(String.valueOf(new Date().getTime())).build());
+
+        UpdateItemRequest request = UpdateItemRequest.builder()
+                .tableName(DDB_TABLE)
+                .key(itemKey)
+                .updateExpression("set contract_status=:t, modified_date=:m")
+                .expressionAttributeValues(expressionAttributeValues)
+                .conditionExpression(
+                        "attribute_exists(property_id) AND contract_status IN (:draft)")
+                .build();
+        try {
+            dynamodbClient.updateItem(request);
+        } catch (ConditionalCheckFailedException conditionalCheckFailedException) {
+            logger.error("Unable to update contract for Property '" + contract.getPropertyId()
+                    + "'.Status is not in " + ContractStatusEnum.DRAFT);
+        } catch (ResourceNotFoundException conditionalCheckFailedException) {
+            logger.error("Unable to update contract for Property '" + contract.getPropertyId()
+                    + "'. Not Found");
+        }
+    }
+
+    public void setDynamodbClient(DynamoDbClient dynamodbClient) {
+        this.dynamodbClient = dynamodbClient;
+    }
+
+}