Implementing persisting action result mutations

app/imports/api/engine/action/functions/mutationToPropUpdates.ts

@@ -0,0 +1,43 @@
+import { Mutation } from '/imports/api/engine/action/tasks/TaskResult';
+import { newOperation } from '/imports/api/engine/shared/bulkWrite';
+
+export default function mutationToPropUpdates(mutation: Mutation) {
+  const bulkWriteOps: any[] = [];
+  // Updates to creature properties
+  if (mutation.updates) {
+    const propUpdatesById: Record<string, any> = {};
+    for (const update of mutation.updates) {
+      if (!propUpdatesById[update.propId]) {
+        propUpdatesById[update.propId] = newOperation(update.propId);
+      }
+      if (update.set) {
+        propUpdatesById[update.propId].updateOne.update.$set = {
+          ...propUpdatesById[update.propId].updateOne.update.$set,
+          ...update.set,
+        };
+      }
+      if (update.inc) {
+        propUpdatesById[update.propId].updateOne.update.$inc = {
+          ...propUpdatesById[update.propId].updateOne.update.$inc,
+          ...update.inc,
+        };
+      }
+    }
+    for (const id in propUpdatesById) {
+      bulkWriteOps.push(propUpdatesById[id]);
+    }
+  }
+  // Insert creature properties
+  if (mutation.inserts) for (const insertOne of mutation.inserts) {
+    bulkWriteOps.push({
+      insertOne
+    });
+  }
+  // Remove creature properties
+  if (mutation.removals) for (const removeOne of mutation.removals) {
+    bulkWriteOps.push({
+      removeOne,
+    });
+  }
+  return bulkWriteOps;
+}