public SqsToIotCoreStack()

in dynamodb-api/src/main/java/com/awssamples/dynamodbapi/SqsToIotCoreStack.java [148:252]
76 lines of code
2 McCabe index (conditional complexity)

    public SqsToIotCoreStack(final Construct parent, final String name) {
        super(parent, name);

        // Build all of the necessary JARs
        build();

        Map<String, String> arguments = CdkHelper.getArguments();

        // Get the queue ARN from the arguments or build the message queue and extract the ARN
        String inboundSqsQueueArn = getInboundQueueArn()
                .getOrElse(() -> buildInboundMessageQueue().getQueueArn());

        String outboundSqsQueueArn = getOutboundQueueArn()
                .getOrElse(() -> buildOutboundMessageQueue().getQueueArn());

        Table messageTable = buildMessageTable();

        String uuidName = getUuid()
                .getOrElse(this::getDefaultUuidNameAndWarn);

        String messageIdName = getMessageId()
                .getOrElse(this::getDefaultMessageNameIdAndWarn);

        // Resources to move messages from SQS to DynamoDB
        Role moveFromSqsToDynamoDbRole = buildMoveFromSqsToDynamoDbRole(inboundSqsQueueArn, messageTable);
        Function moveFromSqsToDynamoDb = buildMoveFromSqsToDynamoDbLambda(inboundSqsQueueArn, uuidName, messageIdName, messageTable, moveFromSqsToDynamoDbRole);
        buildEventSourceMapping(inboundSqsQueueArn, moveFromSqsToDynamoDb);

        // Default environment for all functions just contains the table name
        Map<String, String> defaultEnvironment = getDefaultEnvironment(messageTable);

        // Resources to get messages from DynamoDB and publish to IoT Core
        List<PolicyStatement> getItemPolicyStatementsForMessageTable = List.of(getGetItemPolicyStatementForTable(messageTable));
        Role getRole = buildIotEventRoleForTopicPrefix(GET_ROLE_NAME, GET_RESPONSE_TOPIC_PREFIX, getItemPolicyStatementsForMessageTable, List.empty());
        String getRequestTopicFilter = String.join(MQTT_TOPIC_SEPARATOR, GET_REQUEST_TOPIC_PREFIX, MULTI_LEVEL_MQTT_WILDCARD);
        Map<String, String> getMessageLambdaEnvironment = getGetMessageLambdaEnvironment();
        Function getLambda = buildIotEventLambda(GET_LAMBDA_FUNCTION_NAME, getRole, defaultEnvironment, getMessageLambdaEnvironment, GET_METHOD_NAME);
        CfnTopicRule getRule = buildIotEventRule(this, GET_RULE_NAME, getLambda, DEFAULT_SELECT_CLAUSE, getRequestTopicFilter);
        allowIotTopicRuleToInvokeLambdaFunction(this, getRule, getLambda, GET_LAMBDA_PERMISSIONS);

        // Resources to query for available messages from DynamoDB and publish to IoT Core
        List<PolicyStatement> queryPolicyStatementsForMessageTable = List.of(getQueryPolicyStatementForTable(messageTable));
        Role queryRole = buildIotEventRoleForTopicPrefix(QUERY_ROLE_NAME, QUERY_RESPONSE_TOPIC_PREFIX, queryPolicyStatementsForMessageTable, List.empty());
        String queryRequestTopicFilter = String.join(MQTT_TOPIC_SEPARATOR, QUERY_REQUEST_TOPIC_PREFIX, MULTI_LEVEL_MQTT_WILDCARD);
        Map<String, String> queryMessageLambdaEnvironment = getQueryMessageLambdaEnvironment();
        Function queryLambda = buildIotEventLambda(QUERY_LAMBDA_FUNCTION_NAME, queryRole, defaultEnvironment, queryMessageLambdaEnvironment, QUERY_METHOD_NAME);
        CfnTopicRule queryRule = buildIotEventRule(this, QUERY_RULE_NAME, queryLambda, DEFAULT_SELECT_CLAUSE, queryRequestTopicFilter);
        allowIotTopicRuleToInvokeLambdaFunction(this, queryRule, queryLambda, QUERY_LAMBDA_PERMISSIONS);

        // Resources to delete messages from DynamoD0
        List<PolicyStatement> deleteItemPolicyStatementsForMessageTable = List.of(getDeleteItemPolicyStatementForTable(messageTable));
        Role deleteRole = buildIotEventRoleForTopicPrefix(DELETE_ROLE_NAME, DELETE_RESPONSE_TOPIC_PREFIX, deleteItemPolicyStatementsForMessageTable, List.empty());
        String deleteRequestTopicFilter = String.join(MQTT_TOPIC_SEPARATOR, DELETE_REQUEST_TOPIC_PREFIX, MULTI_LEVEL_MQTT_WILDCARD);
        Map<String, String> deleteMessageLambdaEnvironment = getDeleteMessageLambdaEnvironment();
        Function deleteLambda = buildIotEventLambda(DELETE_LAMBDA_FUNCTION_NAME, deleteRole, defaultEnvironment, deleteMessageLambdaEnvironment, DELETE_METHOD_NAME);
        CfnTopicRule deleteRule = buildIotEventRule(this, DELETE_RULE_NAME, deleteLambda, DEFAULT_SELECT_CLAUSE, deleteRequestTopicFilter);
        allowIotTopicRuleToInvokeLambdaFunction(this, deleteRule, deleteLambda, DELETE_LAMBDA_PERMISSIONS);

        // Resources to get the next message ID from DynamoDB
        List<PolicyStatement> nextItemPolicyStatementsForMessageTable = List.of(getNextItemPolicyStatementForTable(messageTable));
        Role nextRole = buildIotEventRoleForTopicPrefix(NEXT_ROLE_NAME, NEXT_RESPONSE_TOPIC_PREFIX, nextItemPolicyStatementsForMessageTable, List.empty());
        String nextRequestTopicFilter = String.join(MQTT_TOPIC_SEPARATOR, NEXT_REQUEST_TOPIC_PREFIX, MULTI_LEVEL_MQTT_WILDCARD);
        Map<String, String> nextMessageLambdaEnvironment = getNextMessageLambdaEnvironment();
        Function nextLambda = buildIotEventLambda(NEXT_LAMBDA_FUNCTION_NAME, nextRole, defaultEnvironment, nextMessageLambdaEnvironment, NEXT_METHOD_NAME);
        CfnTopicRule nextRule = buildIotEventRule(this, NEXT_RULE_NAME, nextLambda, DEFAULT_SELECT_CLAUSE, nextRequestTopicFilter);
        allowIotTopicRuleToInvokeLambdaFunction(this, nextRule, nextLambda, NEXT_LAMBDA_PERMISSIONS);

        // Resources to get the list of devices with unread messages from DynamoDB
        Map<String, String> devicesMessageLambdaEnvironment = getDevicesMessageLambdaEnvironment();
        Function devicesLambda;

        if (dynamoDbDeviceLookup) {
            List<PolicyStatement> devicesDynamoDbPolicyStatementsForMessageTable = List.of(getDevicesPolicyStatementForTable(messageTable));
            Role dynamoDbDevicesRole = buildIotEventRoleForTopic(DEVICES_ROLE_NAME, DEVICES_RESPONSE_TOPIC, devicesDynamoDbPolicyStatementsForMessageTable, List.empty());
            Function dynamoDbDevicesLambda = buildIotEventLambda(DEVICES_LAMBDA_FUNCTION_NAME, dynamoDbDevicesRole, defaultEnvironment, devicesMessageLambdaEnvironment, DEVICES_DYNAMODB_METHOD_NAME);
            devicesLambda = dynamoDbDevicesLambda;
        } else {
            List<PolicyStatement> devicesRegistryPolicyStatements = List.of(searchIndexPolicyStatement);
            Role registryDevicesRole = buildIotEventRoleForTopic(DEVICES_ROLE_NAME, DEVICES_RESPONSE_TOPIC, devicesRegistryPolicyStatements, List.empty());
            Function registryDevicesLambda = buildIotEventLambda(DEVICES_LAMBDA_FUNCTION_NAME, registryDevicesRole, defaultEnvironment, devicesMessageLambdaEnvironment, DEVICES_REGISTRY_METHOD_NAME);
            devicesLambda = registryDevicesLambda;
        }

        CfnTopicRule devicesRule = buildIotEventRule(this, DEVICES_RULE_NAME, devicesLambda, DEFAULT_SELECT_CLAUSE, DEVICES_REQUEST_TOPIC);
        allowIotTopicRuleToInvokeLambdaFunction(this, devicesRule, devicesLambda, DEVICES_LAMBDA_PERMISSIONS);

        // Resources to send messages to SQS
        List<PolicyStatement> sendToSqsPolicyStatements = List.of(getSqsSendMessagePolicyStatement(outboundSqsQueueArn));
        Role sendRole = buildIotEventRoleForTopicPrefix(SEND_ROLE_NAME, SEND_RESPONSE_TOPIC_PREFIX, sendToSqsPolicyStatements, List.empty());
        String sendRequestTopicFilter = String.join(MQTT_TOPIC_SEPARATOR, SEND_REQUEST_TOPIC_PREFIX, MULTI_LEVEL_MQTT_WILDCARD);
        Map<String, String> sendMessageLambdaEnvironment = getSendMessageLambdaEnvironment(outboundSqsQueueArn);
        Function sendLambda = buildIotEventLambda(SEND_LAMBDA_FUNCTION_NAME, sendRole, defaultEnvironment, sendMessageLambdaEnvironment, SEND_METHOD_NAME);
        CfnTopicRule sendRule = buildIotEventRule(this, SEND_RULE_NAME, sendLambda, DEFAULT_SELECT_CLAUSE, sendRequestTopicFilter);
        allowIotTopicRuleToInvokeLambdaFunction(this, sendRule, sendLambda, SEND_LAMBDA_PERMISSIONS);

        // Resources to receive notifications and add devices to the registry
        List<PolicyStatement> notificationCreateThingPolicyStatements = List.of(createThingPolicyStatement,
                updateThingShadowPolicyStatement,
                updateThingGroupsForThingPolicyStatement,
                createThingGroupPolicyStatement);
        Role notificationRole = buildRoleAssumedByLambda(this, NOTIFICATION_ROLE_NAME, notificationCreateThingPolicyStatements, List.of());
        Function notificationLambda = buildIotEventLambda(NOTIFICATION_LAMBDA_FUNCTION_NAME, notificationRole, defaultEnvironment, NOTIFICATION_METHOD_NAME);
        CfnTopicRule notificationRule = buildIotEventRule(this, NOTIFICATION_RULE_NAME, notificationLambda, DEFAULT_SELECT_CLAUSE, NOTIFICATION_TOPIC_FILTER);
        allowIotTopicRuleToInvokeLambdaFunction(this, notificationRule, notificationLambda, NOTIFICATION_LAMBDA_PERMISSIONS);
    }