v0.1.2 - Bulkification updates for flow (#10)

* Bulkification updates for flow

README.md

@@ -5,12 +5,12 @@
 
 ## Deployment
 
-<a href="https://login.salesforce.com/packaging/installPackage.apexp?p0=04t6g000008fjhFAAQ">
+<a href="https://login.salesforce.com/packaging/installPackage.apexp?p0=04t6g000008fjhyAAA">
   <img alt="Deploy to Salesforce"
        src="./media/deploy-package-to-prod.png">
 </a>
 
-<a href="https://test.salesforce.com/packaging/installPackage.apexp?p0=04t6g000008fjhFAAQ">
+<a href="https://test.salesforce.com/packaging/installPackage.apexp?p0=04t6g000008fjhyAAA">
   <img alt="Deploy to Salesforce Sandbox"
        src="./media/deploy-package-to-sandbox.png">
 </a>

core/classes/FlowRoundRobinAssigner.cls

@@ -1,8 +1,6 @@
 global without sharing class FlowRoundRobinAssigner {
   @TestVisible
   private static RoundRobinAssigner.IAssignmentRepo stubAssignmentRepo;
-  @TestVisible
-  private static Boolean hasBeenUpdated = false;
 
   private static final Set<Id> PROCESSED_RECORD_IDS = new Set<Id>();
   private static final FlowRoundRobinAssigner SELF = new FlowRoundRobinAssigner();
@@ -26,16 +24,23 @@ global without sharing class FlowRoundRobinAssigner {
 
   @InvocableMethod(category='Round Robin' label='Round robin records')
   global static void assign(List<FlowInput> flowInputs) {
-    if (hasBeenUpdated == false) {
-      for (FlowInput input : flowInputs) {
-        if (input.recordsToRoundRobin?.isEmpty() != false && input.recordToRoundRobin != null) {
-          input.recordsToRoundRobin = new List<SObject>{ input.recordToRoundRobin };
-        }
-        if (input.recordsToRoundRobin.isEmpty() == false) {
-          SELF.trackAssignedIds(input);
-          SELF.roundRobin(input);
-        }
+    FlowInput bulkifiedInput;
+    for (FlowInput input : flowInputs) {
+      if (bulkifiedInput == null) {
+        bulkifiedInput = input;
+      }
+      if (input.recordsToRoundRobin?.isEmpty() != false && input.recordToRoundRobin != null) {
+        input.recordsToRoundRobin = new List<SObject>{ input.recordToRoundRobin };
       }
+      bulkifiedInput.recordsToRoundRobin.addAll(input.recordsToRoundRobin);
+    }
+
+    if (bulkifiedInput?.recordsToRoundRobin.isEmpty() == false) {
+      SELF.trackAssignedIds(bulkifiedInput);
+      SELF.roundRobin(bulkifiedInput);
+    }
+    if (bulkifiedInput?.updateRecords == true) {
+      update bulkifiedInput.recordsToRoundRobin;
     }
   }
 
@@ -44,10 +49,6 @@ global without sharing class FlowRoundRobinAssigner {
     RoundRobinAssigner.IAssignmentRepo assignmentRepo = this.getAssignmentRepo(input);
     RoundRobinAssigner.Details assignmentDetails = this.getAssignmentDetails(input);
     new RoundRobinAssigner(assignmentRepo, assignmentDetails).assignOwners(input.recordsToRoundRobin);
-    if (input.updateRecords) {
-      update input.recordsToRoundRobin;
-      hasBeenUpdated = true;
-    }
   }
 
   private void validateInput(FlowInput input) {

core/classes/FlowRoundRobinAssignerTests.cls

@@ -60,7 +60,6 @@ private class FlowRoundRobinAssignerTests {
 
     FlowRoundRobinAssigner.assign(new List<FlowRoundRobinAssigner.FlowInput>{ input });
 
-    System.assertEquals(true, FlowRoundRobinAssigner.hasBeenUpdated);
     System.assertEquals(UserInfo.getUserId(), cpa.OwnerId);
   }
 

core/classes/QueryAssigner.cls

@@ -1,9 +1,17 @@
 public without sharing class QueryAssigner implements RoundRobinAssigner.IAssignmentRepo {
+  private static final Map<String, List<SObject>> QUERY_TO_RECORDS = new Map<String, List<SObject>>();
   private final List<Id> validAssignmentIds;
 
   public QueryAssigner(String query, String assignmentFieldName) {
     Set<Id> assignmentIds = new Set<Id>();
-    List<SObject> matchingRecords = Database.query(query);
+    List<SObject> matchingRecords;
+    if (QUERY_TO_RECORDS.containsKey(query)) {
+      matchingRecords = QUERY_TO_RECORDS.get(query);
+    } else {
+      matchingRecords = Database.query(query);
+      QUERY_TO_RECORDS.put(query, matchingRecords);
+    }
+
     for (SObject matchingRecord : matchingRecords) {
       assignmentIds.add((Id) matchingRecord.get(assignmentFieldName));
     }

core/classes/RoundRobinRepository.cls

@@ -1,7 +1,6 @@
 public without sharing class RoundRobinRepository extends AbstractCacheRepo {
   private static Map<String, RoundRobin__c> CACHED_ASSIGNMENTS;
 
-  @SuppressWarnings('PMD.ApexCRUDViolation')
   public void accept(IThreadSafeCacheVisitor visitor, List<SObject> records) {
     RoundRobin__c currentAssignment = this.getCurrentAssignment(visitor.getVisitKey());
     visitor.visitRecords(records, currentAssignment);
@@ -47,39 +46,56 @@ public without sharing class RoundRobinRepository extends AbstractCacheRepo {
 
   @SuppressWarnings('PMD.ApexCRUDViolation')
   private Boolean commitUpdatedAssignment(RoundRobin__c assignment) {
-    Boolean wasCommitSuccessful = true;
     Map<String, RoundRobin__c> currentCache = this.getCachedAssignments();
     if (
       currentCache.containsKey(assignment.Name) &&
       currentCache.get(assignment.Name).LastUpdated__c > CACHED_ASSIGNMENTS.get(assignment.Name).LastUpdated__c
     ) {
-      assignment = currentCache.get(assignment.Name);
-      wasCommitSuccessful = false;
-    } else {
-      assignment.LastUpdated__c = System.now();
-      /**
-       * integration tests with after save Flows have shown something unfortunate:
-       * though the second (recursive) call to the assigner is spawned in a second transaction
-       * the RoundRobin__c.getAll() still doesn't contain the Id of the inserted record (for the times where the assignment
-       * is being run for the first time).
-       * That means that we can't just call "upsert", and instead have to do this goofy
-       * song and dance to ensure the Id is appended correctly
-       */
-      if (assignment.Id == null) {
-        List<RoundRobin__c> existingAssignments = [SELECT Id FROM RoundRobin__c WHERE Name = :assignment.Name];
-        if (existingAssignments.isEmpty() == false) {
-          assignment.Id = existingAssignments[0].Id;
-        }
+      return false;
+    }
+    assignment.LastUpdated__c = System.now();
+    /**
+     * integration tests with after save Flows have shown something unfortunate:
+     * though the second (recursive) call to the assigner is spawned in a second transaction
+     * the RoundRobin__c.getAll() call still doesn't contain the Id of the inserted record (for the times where the assignment
+     * is being run for the first time).
+     * That means that we can't just call "upsert", and instead have to do this goofy
+     * song and dance to ensure the Id is appended correctly
+     */
+    if (assignment.Id == null) {
+      List<RoundRobin__c> existingAssignments = [SELECT Id FROM RoundRobin__c WHERE Name = :assignment.Name];
+      if (existingAssignments.isEmpty() == false) {
+        assignment.Id = existingAssignments[0].Id;
       }
-      if (assignment.Id != null) {
-        update assignment;
-      } else {
-        insert assignment;
+    }
+    if (assignment.Id != null) {
+      try {
+        /**
+         * if two separate threads are trying to round robin at the same time, the LastUpdated__c check above
+         * isn't enough to ensure write-safety, and unfortunately FOR UPDATE is the only mutex Apex offers
+         * as a write-safe guarantee. One downside (among many) is that FOR UPDATE frequently throws; another is
+         * that another locking thread can release early - let's protect against both those eventualities
+         */
+        RoundRobin__c lockedAssignment = [SELECT Id, Name, LastUpdated__c FROM RoundRobin__c WHERE Id = :assignment.Id FOR UPDATE];
+        if (lockedAssignment.LastUpdated__c >= assignment.LastUpdated__c) {
+          // lock was released early, but the existing Index__c now almost certainly has stale values in it
+          // re-round robin to get the now-correct values
+          return false;
+        }
+        lockedAssignment.Index__c = assignment.Index__c;
+        lockedAssignment.LastUpdated__c = assignment.LastUpdated__c;
+        update lockedAssignment;
+        // purely for the map assignment, below
+        assignment = lockedAssignment;
+      } catch (DmlException ex) {
+        return false;
       }
+    } else {
+      insert assignment;
     }
 
     CACHED_ASSIGNMENTS.put(assignment.Name, assignment);
-    return wasCommitSuccessful;
+    return true;
   }
 
   private Map<String, RoundRobin__c> getCachedAssignments() {

integration-tests/classes/RoundRobinFlowIntegrationTests.cls

@@ -14,10 +14,16 @@ private class RoundRobinFlowIntegrationTests {
     roundRobinUser.LastName = 'roundRobinUser';
     insert roundRobinUser;
 
-    Lead lead = new Lead(LastName = 'Test Assignment', Company = 'Test');
-    insert lead;
+    List<Lead> leads = new List<Lead>();
+    // stress test!
+    for (Integer index = 0; index < 200; index++) {
+      leads.add(new Lead(LastName = 'Assignment ' + index, Company = 'Round Robin'));
+    }
+    insert leads;
 
-    lead = [SELECT Id, OwnerId FROM Lead];
-    System.assertEquals(roundRobinUser.Id, lead.OwnerId);
+    leads = [SELECT Id, OwnerId FROM Lead];
+    for (Lead lead : leads) {
+      System.assertEquals(roundRobinUser.Id, lead.OwnerId);
+    }
   }
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "salesforce-round-robin",
-  "version": "0.1.1",
+  "version": "0.1.2",
   "description": "Round robin records in Salesforce (SFDC) using Flow or Apex. Performant, fair, fast assignment with configurable user pools",
   "repository": {
     "type": "git",

sfdx-project.json

@@ -5,8 +5,8 @@
             "definitionFile": "config/project-scratch-def.json",
             "package": "salesforce-round-robin",
             "path": "core",
-            "versionName": "Reverts mutex due to bulkification issues with Flow, adds more safety for recursive Flow transactions",
-            "versionNumber": "0.1.1.0",
+            "versionName": "Better flow bulkification for updates, reinstated mutex",
+            "versionNumber": "0.1.2.0",
             "versionDescription": "Invocable & Apex-ready Round Robin Assigner for Salesforce Flow, Process Builder, Apex and more",
             "releaseNotesUrl": "https://github.com/jamessimone/salesforce-round-robin/releases/latest"
         },
@@ -21,6 +21,7 @@
         "salesforce-round-robin": "0Ho6g000000GnClCAK",
         "salesforce-round-robin@0.0.4-0": "04t6g000008SjZEAA0",
         "salesforce-round-robin@0.1.0-0": "04t6g000008SjpyAAC",
-        "salesforce-round-robin@0.1.1-0": "04t6g000008fjhFAAQ"
+        "salesforce-round-robin@0.1.1-0": "04t6g000008fjhFAAQ",
+        "salesforce-round-robin@0.1.2-0": "04t6g000008fjhyAAA"
     }
 }