Refactor & fix sweeper

Fixes #47

server/src/main/java/io/orkes/conductor/server/service/OrkesSweeperProperties.java

@@ -20,11 +20,12 @@
 import lombok.ToString;
 
 @Configuration
-@ConfigurationProperties("conductor.app.sweeper")
+@ConfigurationProperties("conductor.orkes.sweeper")
 @Getter
 @Setter
 @ToString
 public class OrkesSweeperProperties {
+    private int frequencyMillis = 10;
     private int sweepBatchSize = 5;
     private int queuePopTimeout = 100;
 }

server/src/main/java/io/orkes/conductor/server/service/OrkesWorkflowSweepWorker.java

@@ -0,0 +1,221 @@
+/*
+ * Copyright 2023 Orkes, Inc.
+ * <p>
+ * Licensed under the Orkes Community License (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ * <p>
+ * https://github.com/orkes-io/licenses/blob/main/community/LICENSE.txt
+ * <p>
+ * 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.
+ */
+package io.orkes.conductor.server.service;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.concurrent.CompletableFuture;
+import java.util.stream.Collectors;
+
+import org.apache.commons.lang3.StringUtils;
+import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
+import org.springframework.scheduling.annotation.Async;
+import org.springframework.stereotype.Component;
+
+import com.netflix.conductor.core.config.ConductorProperties;
+import com.netflix.conductor.core.dal.ExecutionDAOFacade;
+import com.netflix.conductor.core.exception.NotFoundException;
+import com.netflix.conductor.core.execution.WorkflowExecutor;
+import com.netflix.conductor.core.execution.tasks.SystemTaskRegistry;
+import com.netflix.conductor.core.execution.tasks.WorkflowSystemTask;
+import com.netflix.conductor.core.utils.QueueUtils;
+import com.netflix.conductor.core.utils.Utils;
+import com.netflix.conductor.dao.QueueDAO;
+import com.netflix.conductor.metrics.Monitors;
+import com.netflix.conductor.model.TaskModel;
+import com.netflix.conductor.model.WorkflowModel;
+
+import io.orkes.conductor.metrics.MetricsCollector;
+
+import lombok.extern.slf4j.Slf4j;
+
+import static com.netflix.conductor.core.config.SchedulerConfiguration.SWEEPER_EXECUTOR_NAME;
+import static com.netflix.conductor.core.utils.Utils.DECIDER_QUEUE;
+
+@Component
+@ConditionalOnProperty(name = "conductor.orkes.sweeper.enabled", havingValue = "true")
+@Slf4j
+public class OrkesWorkflowSweepWorker {
+
+    private final QueueDAO queueDAO;
+    private final ConductorProperties properties;
+    private final WorkflowExecutor workflowExecutor;
+    private final ExecutionDAOFacade executionDAOFacade;
+    private final MetricsCollector metricsCollector;
+    private final SystemTaskRegistry systemTaskRegistry;
+
+    public OrkesWorkflowSweepWorker(
+            QueueDAO queueDAO,
+            WorkflowExecutor workflowExecutor,
+            ExecutionDAOFacade executionDAOFacade,
+            MetricsCollector metricsCollector,
+            SystemTaskRegistry systemTaskRegistry,
+            ConductorProperties properties) {
+        this.queueDAO = queueDAO;
+        this.executionDAOFacade = executionDAOFacade;
+        this.metricsCollector = metricsCollector;
+        this.systemTaskRegistry = systemTaskRegistry;
+        this.properties = properties;
+        this.workflowExecutor = workflowExecutor;
+    }
+
+    @Async(SWEEPER_EXECUTOR_NAME)
+    public CompletableFuture<Void> sweepAsync(String workflowId) {
+        metricsCollector.getTimer("workflowSweeper").record(() -> sweep(workflowId));
+        return CompletableFuture.completedFuture(null);
+    }
+
+    private void sweep(String workflowId) {
+        try {
+            log.info("Running sweeper for workflow {}", workflowId);
+            // 1. Run decide on the workflow
+            WorkflowModel workflow = decideAndRemove(workflowId);
+            if (workflow == null || workflow.getStatus().isTerminal()) {
+                if (workflow == null) {
+                    // The workflow does not exist anymore, possible if it was completed and
+                    // archived
+                    queueDAO.remove(DECIDER_QUEUE, workflowId);
+                }
+                return;
+            }
+
+            // 2. If decide returns false
+            //    - Check if the workflow has at least one scheduled or in progress task?
+            //    - If scheduled or in progress - Check if it exists in its corresponding queue, if
+            // not add it back
+            //    - If no scheduled or in progress task exists
+            //         1. Set the last task as isExecuted = false to force a re-evaluation
+            //         2. Call decide
+
+            if (System.currentTimeMillis() - workflow.getUpdatedTime() < 60_000L) {
+                // Only do this once every 60 second
+                return;
+            }
+            List<TaskModel> pendingTasks = getAllPendingTasks(workflow);
+            if (pendingTasks.size() > 0) {
+                pendingTasks.forEach(this::ensurePendingTaskIsInQueue);
+            } else {
+                log.warn(
+                        "Workflow {} doesn't have an open pending task, requires force evaluation",
+                        workflow.getWorkflowId());
+                forceSetLastTaskAsNotExecuted(workflow);
+                workflow = decideAndRemove(workflowId);
+                log.debug(
+                        "Force evaluation result for workflow {} - {}",
+                        workflowId,
+                        workflow == null ? null : workflow.getStatus());
+                if (workflow == null || workflow.getStatus().isTerminal()) {
+                    return;
+                }
+            }
+            // 3. If parent workflow exists, call repair on that too - meaning ensure the parent is
+            // in the decider queue
+            if (workflow.getParentWorkflowId() != null) {
+                ensureWorkflowExistsInDecider(workflow.getParentWorkflowId());
+            }
+        } catch (NotFoundException e) {
+            queueDAO.remove(DECIDER_QUEUE, workflowId);
+            log.info("Workflow NOT found for id:{}. Removed it from decider queue", workflowId, e);
+            return;
+        } catch (Exception e) {
+            log.error("Error running sweep for " + workflowId, e);
+        }
+
+        // 4. TODO: Don't do this now - Check the min timeout for all running tasks and set
+        //          Math.min(minTime, 1 hour) for decider queue
+        queueDAO.setUnackTimeout(
+                DECIDER_QUEUE, workflowId, properties.getWorkflowOffsetTimeout().toMillis());
+    }
+
+    private void forceSetLastTaskAsNotExecuted(WorkflowModel workflow) {
+        if (workflow.getTasks() != null && workflow.getTasks().size() > 0) {
+            TaskModel taskModel = workflow.getTasks().get(workflow.getTasks().size() - 1);
+            log.warn(
+                    "Force setting isExecuted to false for last task - {} for workflow {}",
+                    taskModel.getTaskId(),
+                    taskModel.getWorkflowInstanceId());
+            taskModel.setExecuted(false);
+            executionDAOFacade.updateTask(taskModel);
+        }
+    }
+
+    private List<TaskModel> getAllPendingTasks(WorkflowModel workflow) {
+        if (workflow.getTasks() != null && workflow.getTasks().size() > 0) {
+            return workflow.getTasks().stream()
+                    .filter(taskModel -> !taskModel.isExecuted())
+                    .collect(Collectors.toList());
+        }
+        return Collections.emptyList();
+    }
+
+    /** Decide with lock and remove terminal workflow from <code>DECIDER_QUEUE</code> */
+    private WorkflowModel decideAndRemove(String workflowId) {
+        WorkflowModel workflowModel = executionDAOFacade.getWorkflowModel(workflowId, true);
+        workflowModel = workflowExecutor.decideWithLock(workflowModel);
+        if (workflowModel == null) {
+            return null;
+        }
+        if (workflowModel.getStatus().isTerminal()) {
+            queueDAO.remove(DECIDER_QUEUE, workflowId);
+        }
+        return workflowModel;
+    }
+
+    private boolean ensurePendingTaskIsInQueue(TaskModel task) {
+        if (shouldTaskExistInQueue(task)) {
+            // Ensure QueueDAO contains this taskId
+            String taskQueueName = QueueUtils.getQueueName(task);
+            if (!queueDAO.containsMessage(taskQueueName, task.getTaskId())) {
+                queueDAO.push(taskQueueName, task.getTaskId(), task.getCallbackAfterSeconds());
+                log.info(
+                        "Task {} in workflow {} re-queued for repairs",
+                        task.getTaskId(),
+                        task.getWorkflowInstanceId());
+                metricsCollector
+                        .getCounter("repairTaskReQueued", task.getTaskDefName())
+                        .increment();
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean ensureWorkflowExistsInDecider(String workflowId) {
+        if (StringUtils.isNotEmpty(workflowId)) {
+            String queueName = Utils.DECIDER_QUEUE;
+            if (!queueDAO.containsMessage(queueName, workflowId)) {
+                queueDAO.push(
+                        queueName, workflowId, properties.getWorkflowOffsetTimeout().getSeconds());
+                log.info("Workflow {} re-queued for repairs", workflowId);
+                Monitors.recordQueueMessageRepushFromRepairService(queueName);
+                return true;
+            }
+        }
+        return false;
+    }
+
+    private boolean shouldTaskExistInQueue(TaskModel task) {
+        if (systemTaskRegistry.isSystemTask(task.getTaskType())) {
+            WorkflowSystemTask workflowSystemTask = systemTaskRegistry.get(task.getTaskType());
+            return workflowSystemTask.isAsync() // Is Async
+                    // Not async complete OR is async complete, but in scheduled state
+                    && (!workflowSystemTask.isAsyncComplete(task)
+                            || (workflowSystemTask.isAsyncComplete(task)
+                                    && task.getStatus() == TaskModel.Status.SCHEDULED))
+                    // Status is IN_PROGRESS or SCHEDULED
+                    && (task.getStatus() == TaskModel.Status.IN_PROGRESS
+                            || task.getStatus() == TaskModel.Status.SCHEDULED);
+        }
+        return task.getStatus() == TaskModel.Status.SCHEDULED;
+    }
+}