adamdebreceni commented on a change in pull request #821: URL: https://github.com/apache/nifi-minifi-cpp/pull/821#discussion_r454328316
########## File path: extensions/standard-processors/processors/RetryFlowFile.cpp ########## @@ -0,0 +1,183 @@ +/** + * + * Licensed to the Apache Software Foundation (ASF) under one or more + * contributor license agreements. See the NOTICE file distributed with + * this work for additional information regarding copyright ownership. + * The ASF licenses this file to You under the Apache License, Version 2.0 + * (the "License"); you may not use this file except in compliance with + * the License. You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include "RetryFlowFile.h" + +#include "core/PropertyValidation.h" + +namespace org { +namespace apache { +namespace nifi { +namespace minifi { +namespace processors { + +core::Property RetryFlowFile::RetryAttribute(core::PropertyBuilder::createProperty("Retry Attribute") + ->withDescription( + "The name of the attribute that contains the current retry count for the FlowFile." + "WARNING: If the name matches an attribute already on the FlowFile that does not contain a numerical value, " + "the processor will either overwrite that attribute with '1' or fail based on configuration.") + ->withDefaultValue("flowfile.retries") + ->supportsExpressionLanguage(true) + ->build()); + +core::Property RetryFlowFile::MaximumRetries(core::PropertyBuilder::createProperty("Maximum Retries") + ->withDescription("The maximum number of times a FlowFile can be retried before being passed to the 'retries_exceeded' relationship.") + ->withDefaultValue<uint64_t>(3) + ->supportsExpressionLanguage(true) + ->build()); + +core::Property RetryFlowFile::PenalizeRetries(core::PropertyBuilder::createProperty("Penalize Retries") + ->withDescription("If set to 'true', this Processor will penalize input FlowFiles before passing them to the 'retry' relationship. This does not apply to the 'retries_exceeded' relationship.") + ->withDefaultValue<bool>(true) + ->build()); + +core::Property RetryFlowFile::FailOnNonNumericalOverwrite(core::PropertyBuilder::createProperty("Fail on Non-numerical Overwrite") + ->withDescription("If the FlowFile already has the attribute defined in 'Retry Attribute' that is *not* a number, fail the FlowFile instead of resetting that value to '1'") + ->withDefaultValue<bool>(false) + ->build()); + +core::Property RetryFlowFile::ReuseMode(core::PropertyBuilder::createProperty("Reuse Mode") + ->withDescription( + "Defines how the Processor behaves if the retry FlowFile has a different retry UUID than " + "the instance that received the FlowFile. This generally means that the attribute was " + "not reset after being successfully retried by a previous instance of this processor.") + ->withAllowableValues<std::string>({FAIL_ON_REUSE, WARN_ON_REUSE, RESET_REUSE}) + ->withDefaultValue(FAIL_ON_REUSE) + ->build()); + +core::Relationship RetryFlowFile::Retry("retry", + "Input FlowFile has not exceeded the configured maximum retry count, pass this relationship back to the input Processor to create a limited feedback loop."); +core::Relationship RetryFlowFile::RetriesExceeded("retries_exceeded", + "Input FlowFile has exceeded the configured maximum retry count, do not pass this relationship back to the input Processor to terminate the limited feedback loop."); +core::Relationship RetryFlowFile::Failure("failure", + "The processor is configured such that a non-numerical value on 'Retry Attribute' results in a failure instead of resetting " + "that value to '1'. This will immediately terminate the limited feedback loop. Might also include when 'Maximum Retries' contains " + " attribute expression language that does not resolve to an Integer."); + +void RetryFlowFile::initialize() { + setSupportedProperties({ + RetryAttribute, + MaximumRetries, + PenalizeRetries, + FailOnNonNumericalOverwrite, + ReuseMode, + }); + setSupportedRelationships({ + Retry, + RetriesExceeded, + Failure, + }); +} + +void RetryFlowFile::onSchedule(core::ProcessContext* context, core::ProcessSessionFactory* /* sessionFactory */) { + context->getProperty(RetryAttribute.getName(), retry_attribute_); + context->getProperty(MaximumRetries.getName(), maximum_retries_); + context->getProperty(PenalizeRetries.getName(), penalize_retries_); + context->getProperty(FailOnNonNumericalOverwrite.getName(), fail_on_non_numerical_overwrite_); + context->getProperty(ReuseMode.getName(), reuse_mode_); + readDynamicPropertyKeys(context); +} + +void RetryFlowFile::onTrigger(core::ProcessContext* context, core::ProcessSession* session) { + std::shared_ptr<FlowFileRecord> flow_file = std::static_pointer_cast<FlowFileRecord> (session->get()); + if (!flow_file) { + return; + } + + utils::optional<uint64_t> maybe_retry_property_value = getRetryPropertyValue(flow_file); + if (!maybe_retry_property_value) { + session->transfer(flow_file, Failure); + return; + } + uint64_t retry_property_value = maybe_retry_property_value.value(); + const std::string last_retried_by_property_name = retry_attribute_ + ".uuid"; + const std::string current_processor_uuid = getUUIDStr(); + std::string last_retried_by_uuid; + if (flow_file->getAttribute(last_retried_by_property_name, last_retried_by_uuid)) { + if (last_retried_by_uuid != current_processor_uuid) { + if (reuse_mode_ == FAIL_ON_REUSE) { + logger_->log_error("FlowFile %s was previously retried with the same attribute by a different " + "processor (uuid: %s, current uuid: %s). Transfering flowfile to 'failure'...", + flow_file->getUUIDStr(), last_retried_by_uuid, current_processor_uuid); + session->transfer(flow_file, Failure); + return; + } + // Assuming reuse_mode_ == WARN_ON_REUSE || reuse_mode_ == RESET_REUSE + core::logging::LOG_LEVEL reuse_mode_log_level(core::logging::LOG_LEVEL::debug); Review comment: most vexing parse? ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: us...@infra.apache.org