refactor: Simplify accessing mongoose models

Currently mongoose models are accessed via db connection and require a typecast.
```
import { UserModel } from './user.model';

const User = dbs.admin.model('User') as UserModel;
```

Since model registry is tied to the db connection, there is no need to access it in this way.  We can just import the model (w/ proper typing) directly since it is already being exported.

```
import { User } from './user.model';
```

For use cases where multiple db connections are used.  Models should explicitly be registered on the appropriate connection.
```
// Register model on default/admin db connection
export const MyModel = model('MyModel', MyModelSchema);

// Register model on secondary db connection
export const OtherModel = dbs.other.model('OtherModel', OtherModelSchema);
```

src/app/core/access-checker/access-checker.service.spec.ts

@@ -4,11 +4,9 @@ import should from 'should';
 import { createSandbox } from 'sinon';
 
 import accessChecker from './access-checker.service';
-import { CacheEntryModel, ICacheEntry } from './cache/cache-entry.model';
+import { CacheEntry, ICacheEntry } from './cache/cache-entry.model';
 import cacheEntryService from './cache/cache-entry.service';
-import { config, dbs } from '../../../dependencies';
-
-const CacheEntry = dbs.admin.model('CacheEntry') as CacheEntryModel;
+import { config } from '../../../dependencies';
 
 /**
  * Helpers

src/app/core/access-checker/cache/cache-entry.service.spec.ts

@@ -1,10 +1,7 @@
 import should from 'should';
 
-import { CacheEntryModel } from './cache-entry.model';
+import { CacheEntry } from './cache-entry.model';
 import cacheEntryService from './cache-entry.service';
-import { dbs } from '../../../../dependencies';
-
-const CacheEntry = dbs.admin.model('CacheEntry') as CacheEntryModel;
 
 /**
  * Unit tests

src/app/core/access-checker/cache/cache-entry.service.ts

@@ -1,15 +1,15 @@
 import { FilterQuery } from 'mongoose';
 
-import { CacheEntryDocument, CacheEntryModel } from './cache-entry.model';
-import { dbs, utilService } from '../../../../dependencies';
+import {
+	CacheEntry,
+	CacheEntryDocument,
+	CacheEntryModel
+} from './cache-entry.model';
+import { utilService } from '../../../../dependencies';
 import { PagingResults } from '../../../common/mongoose/paginate.plugin';
 
 class CacheEntryService {
-	model: CacheEntryModel;
-
-	constructor() {
-		this.model = dbs.admin.model('CacheEntry') as CacheEntryModel;
-	}
+	constructor(private model: CacheEntryModel) {}
 
 	/**
 	 * Get the entry from the cache. Gets the most recent version.
@@ -68,4 +68,4 @@ class CacheEntryService {
 	}
 }
 
-export = new CacheEntryService();
+export = new CacheEntryService(CacheEntry);

src/app/core/access-checker/cache/cache-refresh.job.ts

@@ -1,12 +1,10 @@
 import { Job } from 'agenda';
 
-import { CacheEntryModel } from './cache-entry.model';
-import { dbs, logger } from '../../../../dependencies';
+import { CacheEntry } from './cache-entry.model';
+import { logger } from '../../../../dependencies';
 import { JobService } from '../../../common/agenda/job-service';
 import accessChecker from '../access-checker.service';
 
-const CacheEntry = dbs.admin.model('CacheEntry') as CacheEntryModel;
-
 export default class CacheRefreshJobService implements JobService {
 	async run(job: Job) {
 		const refresh = job.attrs.data.refresh ?? 8 * 3600000; // default to 8 hours;

src/app/core/audit/audit.controller.ts

@@ -1,9 +1,7 @@
 import _ from 'lodash';
 
-import { AuditModel } from './audit.model';
-import { dbs, utilService as util } from '../../../dependencies';
-
-const Audit = dbs.admin.model('Audit') as AuditModel;
+import { Audit } from './audit.model';
+import { utilService as util } from '../../../dependencies';
 
 /**
  * Retrieves the distinct values for a field in the Audit collection

src/app/core/audit/audit.service.spec.ts

@@ -1,12 +1,9 @@
 import should from 'should';
 
-import { AuditModel } from './audit.model';
+import { Audit } from './audit.model';
 import auditService from './audit.service';
-import { dbs } from '../../../dependencies';
 import { IUser } from '../user/user.model';
 
-const Audit = dbs.admin.model('Audit') as AuditModel;
-
 /**
  * Globals
  */

src/app/core/audit/audit.service.ts

@@ -1,8 +1,7 @@
 import { Request } from 'express';
 
-import { AuditDocument, AuditModel } from './audit.model';
+import { Audit, AuditDocument } from './audit.model';
 import {
-	dbs,
 	config,
 	logger,
 	auditLogger,
@@ -34,17 +33,14 @@ class AuditService {
 		eventObject: unknown,
 		eventMetadata = null
 	): Promise<AuditDocument> {
-		// Delay resolving the Audit model until we can be sure it has been initialized
-		const Audit = dbs.admin.model('Audit') as AuditModel;
-
 		requestOrEventActor = await requestOrEventActor;
 
 		let actor = {};
 		if (this.isUser(requestOrEventActor)) {
 			actor = requestOrEventActor;
 		} else if (requestOrEventActor.user && requestOrEventActor.headers) {
 			const user = requestOrEventActor.user as UserDocument;
-			actor = await user.auditCopy(
+			actor = user.auditCopy(
 				utilService.getHeaderField(requestOrEventActor.headers, 'x-real-ip')
 			);
 			eventMetadata = requestOrEventActor.headers;

src/app/core/export/export-config.model.ts

@@ -77,7 +77,7 @@ ExportConfigSchema.methods.auditCopy = function () {
 /**
  * Model Registration
  */
-export const Message = model<IExportConfig, ExportConfigModel>(
+export const ExportConfig = model<IExportConfig, ExportConfigModel>(
 	'ExportConfig',
 	ExportConfigSchema
 );

src/app/core/export/export-config.service.ts

@@ -1,10 +1,13 @@
 import { Types } from 'mongoose';
 
-import { ExportConfigDocument, ExportConfigModel } from './export-config.model';
-import { dbs } from '../../../dependencies';
+import {
+	ExportConfig,
+	ExportConfigDocument,
+	ExportConfigModel
+} from './export-config.model';
 
 class ExportConfigService {
-	model = dbs.admin.model('ExportConfig') as ExportConfigModel;
+	constructor(private model: ExportConfigModel) {}
 
 	/**
 	 * Generate a new ExportConfig document in the collection.
@@ -22,4 +25,4 @@ class ExportConfigService {
 	}
 }
 
-export = new ExportConfigService();
+export = new ExportConfigService(ExportConfig);

src/app/core/feedback/feedback.controller.spec.ts

@@ -1,13 +1,10 @@
 import { assert, createSandbox, spy, stub } from 'sinon';
 
 import * as feedbackController from './feedback.controller';
-import { FeedbackModel } from './feedback.model';
+import { Feedback } from './feedback.model';
 import feedbackService from './feedback.service';
-import { auditService, dbs, logger } from '../../../dependencies';
-import { UserModel } from '../user/user.model';
-
-const Feedback = dbs.admin.model('Feedback') as FeedbackModel;
-const User = dbs.admin.model('User') as UserModel;
+import { auditService, logger } from '../../../dependencies';
+import { User } from '../user/user.model';
 
 describe('Feedback Controller2', () => {
 	let res;

src/app/core/feedback/feedback.controller.ts

@@ -1,11 +1,8 @@
-import { FeedbackModel } from './feedback.model';
 import feedbackService from './feedback.service';
-import { auditService, config, dbs, utilService } from '../../../dependencies';
+import { auditService, config } from '../../../dependencies';
 import * as exportConfigController from '../export/export-config.controller';
 import exportConfigService from '../export/export-config.service';
 
-const Feedback = dbs.admin.model('Feedback') as FeedbackModel;
-
 export const submitFeedback = async function (req, res) {
 	const audit = await auditService.audit(
 		'Feedback submitted',
@@ -62,16 +59,16 @@ export const adminGetFeedbackCSV = async function (req, res) {
 
 	const query = result.config.q ? JSON.parse(result.config.q) : null;
 	const search = result.config.s;
-	const sort = utilService.getSortObj(result.config);
 
-	const feedbackCursor = Feedback.find(query)
-		.textSearch(search)
-		.sort(sort)
-		.populate({
+	const feedbackCursor = feedbackService.cursorSearch(
+		result.config,
+		search,
+		query,
+		{
 			path: 'creator',
 			select: ['username', 'organization', 'name', 'email']
-		})
-		.cursor();
+		}
+	);
 
 	exportConfigController.exportCSV(
 		req,
@@ -86,7 +83,11 @@ export const search = async (req, res) => {
 	const results = await feedbackService.search(
 		req.query,
 		req.body.s,
-		req.body.q
+		req.body.q,
+		{
+			path: 'creator',
+			select: ['username', 'organization', 'name', 'email']
+		}
 	);
 	res.status(200).json(results);
 };

src/app/core/feedback/feedback.service.spec.ts

@@ -1,13 +1,10 @@
 import should from 'should';
 import { assert, createSandbox } from 'sinon';
 
-import { FeedbackModel } from './feedback.model';
+import { Feedback } from './feedback.model';
 import feedbackService from './feedback.service';
-import { auditService, emailService, config, dbs } from '../../../dependencies';
-import { UserModel } from '../user/user.model';
-
-const User = dbs.admin.model('User') as UserModel;
-const Feedback = dbs.admin.model('Feedback') as FeedbackModel;
+import { auditService, emailService, config } from '../../../dependencies';
+import { User } from '../user/user.model';
 
 /**
  * Unit tests

src/app/core/feedback/feedback.service.ts

@@ -1,8 +1,14 @@
+import { Readable } from 'stream';
+
 import { FilterQuery, PopulateOptions, Types } from 'mongoose';
 
-import { FeedbackDocument, FeedbackModel, Statuses } from './feedback.model';
 import {
-	dbs,
+	Feedback,
+	FeedbackDocument,
+	FeedbackModel,
+	Statuses
+} from './feedback.model';
+import {
 	config,
 	emailService,
 	logger,
@@ -12,11 +18,7 @@ import { PagingResults } from '../../common/mongoose/paginate.plugin';
 import { UserDocument } from '../user/user.model';
 
 class FeedbackService {
-	model: FeedbackModel;
-
-	constructor() {
-		this.model = dbs.admin.model('Feedback') as FeedbackModel;
-	}
+	constructor(private model: FeedbackModel) {}
 
 	create(
 		user: UserDocument,
@@ -65,7 +67,12 @@ class FeedbackService {
 	search(
 		queryParams = {},
 		search = '',
-		query: FilterQuery<FeedbackDocument> = {}
+		query: FilterQuery<FeedbackDocument> = {},
+		populate:
+			| string
+			| string[]
+			| PopulateOptions
+			| Array<string | PopulateOptions> = []
 	): Promise<PagingResults<FeedbackDocument>> {
 		const page = utilService.getPage(queryParams);
 		const limit = utilService.getLimit(queryParams, 100);
@@ -76,13 +83,30 @@ class FeedbackService {
 			.find(query)
 			.textSearch(search)
 			.sort(sort)
-			.populate({
-				path: 'creator',
-				select: ['username', 'organization', 'name', 'email']
-			})
+			.populate(populate as string[])
 			.paginate(limit, page);
 	}
 
+	cursorSearch(
+		queryParams = {},
+		search = '',
+		query: FilterQuery<FeedbackDocument> = {},
+		populate:
+			| string
+			| string[]
+			| PopulateOptions
+			| Array<string | PopulateOptions> = []
+	): Readable {
+		const sort = utilService.getSortObj(queryParams);
+
+		return this.model
+			.find(query)
+			.textSearch(search)
+			.sort(sort)
+			.populate(populate as string[])
+			.cursor();
+	}
+
 	async sendFeedbackEmail(
 		user: UserDocument,
 		feedback: FeedbackDocument,
@@ -133,4 +157,4 @@ class FeedbackService {
 	}
 }
 
-export = new FeedbackService();
+export = new FeedbackService(Feedback);

src/app/core/messages/messages.service.spec.ts

@@ -1,17 +1,10 @@
 import mongoose from 'mongoose';
 import should from 'should';
 
-import { DismissedMessageModel } from './dismissed-message.model';
-import { MessageModel } from './message.model';
+import { DismissedMessage } from './dismissed-message.model';
+import { Message } from './message.model';
 import messagesService from './messages.service';
-import { dbs } from '../../../dependencies';
-import { UserModel } from '../user/user.model';
-
-const User = dbs.admin.model('User') as UserModel;
-const Message = dbs.admin.model('Message') as MessageModel;
-const DismissedMessage = dbs.admin.model(
-	'DismissedMessage'
-) as DismissedMessageModel;
+import { User } from '../user/user.model';
 
 /**
  * Helpers

src/app/core/messages/messages.service.ts

@@ -3,27 +3,29 @@ import path from 'path';
 import { FilterQuery, PopulateOptions, Types } from 'mongoose';
 
 import {
+	DismissedMessage,
 	DismissedMessageDocument,
 	DismissedMessageModel,
 	IDismissedMessage
 } from './dismissed-message.model';
-import { IMessage, MessageDocument, MessageModel } from './message.model';
-import { dbs, config, utilService } from '../../../dependencies';
+import {
+	IMessage,
+	Message,
+	MessageDocument,
+	MessageModel
+} from './message.model';
+import { config, utilService } from '../../../dependencies';
 import { PublishProvider } from '../../common/event/publish.provider';
 import { PagingResults } from '../../common/mongoose/paginate.plugin';
 import { UserDocument } from '../user/user.model';
 
 class MessagesService {
-	model: MessageModel;
-	dismissedModel: DismissedMessageModel;
 	publishProvider: PublishProvider;
 
-	constructor() {
-		this.model = dbs.admin.model('Message') as MessageModel;
-		this.dismissedModel = dbs.admin.model(
-			'DismissedMessage'
-		) as DismissedMessageModel;
-	}
+	constructor(
+		private model: MessageModel,
+		private dismissedModel: DismissedMessageModel
+	) {}
 
 	create(user: UserDocument, doc: unknown): Promise<MessageDocument> {
 		const message = new this.model(doc);
@@ -144,4 +146,4 @@ class MessagesService {
 	}
 }
 
-export = new MessagesService();
+export = new MessagesService(Message, DismissedMessage);