Batch Couch DB create calls (#6779)

* Implement persistence batching for Couch DB

* Add tests for persistence batching

---------

Co-authored-by: Shefali Joshi <simplyrender@gmail.com>

src/plugins/persistence/couch/CouchObjectProvider.js

@@ -24,6 +24,7 @@ import CouchDocument from './CouchDocument';
 import CouchObjectQueue from './CouchObjectQueue';
 import { PENDING, CONNECTED, DISCONNECTED, UNKNOWN } from './CouchStatusIndicator';
 import { isNotebookOrAnnotationType } from '../../notebook/notebook-constants.js';
+import _ from 'lodash';
 
 const REV = '_rev';
 const ID = '_id';
@@ -42,6 +43,8 @@ class CouchObjectProvider {
     this.batchIds = [];
     this.onEventMessage = this.onEventMessage.bind(this);
     this.onEventError = this.onEventError.bind(this);
+    this.flushPersistenceQueue = _.debounce(this.flushPersistenceQueue.bind(this));
+    this.persistenceQueue = [];
   }
 
   /**
@@ -668,9 +671,12 @@ class CouchObjectProvider {
     if (!this.objectQueue[key].pending) {
       this.objectQueue[key].pending = true;
       const queued = this.objectQueue[key].dequeue();
-      let document = new CouchDocument(key, queued.model);
+      let couchDocument = new CouchDocument(key, queued.model);
-      document.metadata.created = Date.now();
+      couchDocument.metadata.created = Date.now();
-      this.request(key, 'PUT', document)
+      this.#enqueueForPersistence({
+        key,
+        document: couchDocument
+      })
         .then((response) => {
           this.#checkResponse(response, queued.intermediateResponse, key);
         })
@@ -683,6 +689,42 @@ class CouchObjectProvider {
     return intermediateResponse.promise;
   }
 
+  #enqueueForPersistence({ key, document }) {
+    return new Promise((resolve, reject) => {
+      this.persistenceQueue.push({
+        key,
+        document,
+        resolve,
+        reject
+      });
+      this.flushPersistenceQueue();
+    });
+  }
+
+  async flushPersistenceQueue() {
+    if (this.persistenceQueue.length > 1) {
+      const batch = {
+        docs: this.persistenceQueue.map((queued) => queued.document)
+      };
+      const response = await this.request('_bulk_docs', 'POST', batch);
+      response.forEach((responseMetadatum) => {
+        const queued = this.persistenceQueue.find(
+          (queuedMetadatum) => queuedMetadatum.key === responseMetadatum.id
+        );
+        if (responseMetadatum.ok) {
+          queued.resolve(responseMetadatum);
+        } else {
+          queued.reject(responseMetadatum);
+        }
+      });
+    } else if (this.persistenceQueue.length === 1) {
+      const { key, document, resolve, reject } = this.persistenceQueue[0];
+
+      this.request(key, 'PUT', document).then(resolve).catch(reject);
+    }
+    this.persistenceQueue = [];
+  }
+
   /**
    * @private
    */

src/plugins/persistence/couch/pluginSpec.js

@@ -243,6 +243,135 @@ describe('the plugin', () => {
       expect(requestMethod).toEqual('GET');
     });
   });
+  describe('batches persistence', () => {
+    let successfulMockPromise;
+    let partialFailureMockPromise;
+    let objectsToPersist;
+
+    beforeEach(() => {
+      successfulMockPromise = Promise.resolve({
+        json: () => {
+          return [
+            {
+              id: 'object-1',
+              ok: true
+            },
+            {
+              id: 'object-2',
+              ok: true
+            },
+            {
+              id: 'object-3',
+              ok: true
+            }
+          ];
+        }
+      });
+
+      partialFailureMockPromise = Promise.resolve({
+        json: () => {
+          return [
+            {
+              id: 'object-1',
+              ok: true
+            },
+            {
+              id: 'object-2',
+              ok: false
+            },
+            {
+              id: 'object-3',
+              ok: true
+            }
+          ];
+        }
+      });
+
+      objectsToPersist = [
+        {
+          identifier: {
+            namespace: '',
+            key: 'object-1'
+          },
+          name: 'object-1',
+          type: 'folder',
+          modified: 0
+        },
+        {
+          identifier: {
+            namespace: '',
+            key: 'object-2'
+          },
+          name: 'object-2',
+          type: 'folder',
+          modified: 0
+        },
+        {
+          identifier: {
+            namespace: '',
+            key: 'object-3'
+          },
+          name: 'object-3',
+          type: 'folder',
+          modified: 0
+        }
+      ];
+    });
+    it('for multiple simultaneous successful saves', async () => {
+      fetch.and.returnValue(successfulMockPromise);
+
+      await Promise.all(
+        objectsToPersist.map((objectToPersist) => openmct.objects.save(objectToPersist))
+      );
+
+      const requestUrl = fetch.calls.mostRecent().args[0];
+      const requestMethod = fetch.calls.mostRecent().args[1].method;
+      const requestBody = JSON.parse(fetch.calls.mostRecent().args[1].body);
+
+      expect(fetch).toHaveBeenCalledTimes(1);
+      expect(requestUrl.includes('_bulk_docs')).toBeTrue();
+      expect(requestMethod).toEqual('POST');
+      expect(
+        objectsToPersist.every(
+          (object, index) => object.identifier.key === requestBody.docs[index]._id
+        )
+      ).toBeTrue();
+    });
+    it('for multiple simultaneous saves with partial failure', async () => {
+      fetch.and.returnValue(partialFailureMockPromise);
+
+      let saveResults = await Promise.all(
+        objectsToPersist.map((objectToPersist) =>
+          openmct.objects
+            .save(objectToPersist)
+            .then(() => true)
+            .catch(() => false)
+        )
+      );
+      expect(saveResults[0]).toBeTrue();
+      expect(saveResults[1]).toBeFalse();
+      expect(saveResults[2]).toBeTrue();
+    });
+    it('except for a single save', async () => {
+      fetch.and.returnValue({
+        json: () => {
+          return {
+            id: 'object-1',
+            ok: true
+          };
+        }
+      });
+      await openmct.objects.save(objectsToPersist[0]);
+
+      const requestUrl = fetch.calls.mostRecent().args[0];
+      const requestMethod = fetch.calls.mostRecent().args[1].method;
+
+      expect(fetch).toHaveBeenCalledTimes(1);
+      expect(requestUrl.includes('_bulk_docs')).toBeFalse();
+      expect(requestUrl.endsWith('object-1')).toBeTrue();
+      expect(requestMethod).toEqual('PUT');
+    });
+  });
   describe('implements server-side search', () => {
     let mockPromise;
     beforeEach(() => {