feat: add types for result value from getPublic method

Author: jskiller1404

packages/node-mongo/README.md

@@ -276,8 +276,10 @@ Removes private fields from a document and returns a sanitized version. Private
 **Example**
 
 ```typescript
-const service = db.createService<User>("users", {
-  privateFields: ['passwordHash', 'signupToken', 'resetPasswordToken'],
+const USER_PRIVATE_FIELDS = ['passwordHash', 'signupToken', 'resetPasswordToken'] as const
+
+const service = db.createService<User, typeof USER_PRIVATE_FIELDS>("users", {
+  privateFields: USER_PRIVATE_FIELDS,
 });
 
 const user = await service.findOne({ _id: userId });

packages/node-mongo/src/database.ts

@@ -81,11 +81,11 @@ class Database extends EventEmitter {
     await this.client.close();
   };
 
-  createService<T extends IDocument>(
+  createService<T extends IDocument, PrivateFields extends ReadonlyArray<keyof T> = []>(
     collectionName: string,
-    options?: ServiceOptions<T> | undefined,
-  ): Service<T> {
-    return new Service<T>(
+    options?: ServiceOptions<T, PrivateFields> | undefined,
+  ): Service<T, PrivateFields> {
+    return new Service<T, PrivateFields>(
       collectionName,
       this as IDatabase,
       options,

packages/node-mongo/src/service.ts

@@ -38,7 +38,7 @@ import PopulateUtil from './utils/populate';
 
 import { inMemoryPublisher } from './events/in-memory';
 
-const defaultOptions: ServiceOptions<IDocument> = {
+const defaultOptions: ServiceOptions<IDocument, ReadonlyArray<keyof IDocument>> = {
   skipDeletedOnDocs: true,
   publishEvents: true,
   outbox: false,
@@ -50,14 +50,14 @@ const defaultOptions: ServiceOptions<IDocument> = {
 
 const isDev = process.env.NODE_ENV === 'development';
 
-class Service<T extends IDocument> {
+class Service<T extends IDocument, PrivateFields extends ReadonlyArray<keyof T> = []> {
   private client?: MongoClient;
 
   private collection: Collection<T> | null;
 
   private _collectionName: string;
 
-  private options: ServiceOptions<T>;
+  private options: ServiceOptions<T, PrivateFields>;
 
   private db;
 
@@ -68,14 +68,14 @@ class Service<T extends IDocument> {
   constructor(
     collectionName: string,
     db: IDatabase,
-    options: ServiceOptions<T> = {},
+    options: ServiceOptions<T, PrivateFields> = {},
   ) {
     this._collectionName = collectionName;
     this.db = db;
     this.options = {
       ...defaultOptions,
       ...options,
-    };
+    } as ServiceOptions<T, PrivateFields>;
     this.waitForConnection = db.waitForConnection;
 
     if (this.options.outbox) {
@@ -990,9 +990,13 @@ class Service<T extends IDocument> {
     }
   };
 
-  getPublic = <U extends T = T>(doc: U | null): Partial<U> | null => {
-    return omitPrivateFields<U>(doc, this.options.privateFields || []);
-  };
+  getPublic(doc: null): null;
+
+  getPublic(doc: T): Omit<T, PrivateFields[number]>;
+
+  getPublic(doc: T | null): Omit<T, PrivateFields[number]> | null {
+    return omitPrivateFields<T, PrivateFields[number]>(doc, this.options.privateFields || []);
+  }
 }
 
 export default Service;

packages/node-mongo/src/tests/service.spec.ts

@@ -36,6 +36,8 @@ enum AdminPermissions {
   EDIT = 'edit',
 }
 
+const USER_PRIVATE_FIELDS = ['passwordHash'] as const;
+
 const userSchema = z.object({
   _id: z.string(),
   createdOn: z.date().optional(),
@@ -67,9 +69,11 @@ const companyService = database.createService<CompanyType>('companies', {
   schemaValidator: (obj) => companySchema.parseAsync(obj),
 });
 
-const usersServiceWithPrivateFields = database.createService<UserType>('usersWithPrivateFields', {
+
+
+const usersServiceWithPrivateFields = database.createService<UserType, typeof USER_PRIVATE_FIELDS>('usersWithPrivateFields', {
   schemaValidator: (obj) => userSchema.parseAsync(obj),
-  privateFields: ['passwordHash'],
+  privateFields: USER_PRIVATE_FIELDS,
 });
 
 
@@ -1511,7 +1515,9 @@ describe('service.ts', () => {
 
     const publicUser = usersServiceWithPrivateFields.getPublic(user);
 
-    (publicUser?.passwordHash === undefined).should.be.equal(true);
+    // @ts-expect-error Property 'passwordHash' does not exist
+    publicUser?.passwordHash;
+
     publicUser?.fullName?.should.be.equal(userToInsertPayload.fullName);
     publicUser?.age?.should.be.equal(userToInsertPayload.age);
     publicUser?.role?.should.be.equal(userToInsertPayload.role);

packages/node-mongo/src/types/index.ts

@@ -118,7 +118,7 @@ interface IDatabase {
   ) => Promise<TRes>,
 }
 
-interface ServiceOptions<T extends IDocument> {
+interface ServiceOptions<T extends IDocument, PrivateFields extends ReadonlyArray<keyof T> = []> {
   skipDeletedOnDocs?: boolean,
   schemaValidator?: (obj: any) => Promise<any>,
   publishEvents?: boolean,
@@ -128,7 +128,7 @@ interface ServiceOptions<T extends IDocument> {
   collectionOptions?: CollectionOptions;
   collectionCreateOptions?: CreateCollectionOptions;
   escapeRegExp?: boolean;
-  privateFields?: Array<keyof T>;
+  privateFields?: PrivateFields;
 }
 
 export type UpdateFilterFunction<U> = (doc: U) => Partial<U>;

packages/node-mongo/src/utils/helpers.ts

@@ -40,14 +40,13 @@ const addUpdatedOnField = <T>(update: UpdateFilter<T>): UpdateFilter<T> => {
   } as unknown as UpdateFilter<T>;
 };
 
-const omitPrivateFields = <T>(
+const omitPrivateFields = <T extends object, K extends keyof T>(
   doc: T | null,
-  privateFields: Array<keyof T>,
-): Partial<T> | null => {
-  if (!doc) return doc;
+  privateFields: ReadonlyArray<K>,
+): Omit<T, K> | null => {
+  if (!doc) return null;
 
-  return _.omit(doc, privateFields || []) as T;
+  return _.omit<T, K>(doc, privateFields);
 };
 
-
 export { deepCompare, generateId, addUpdatedOnField, omitPrivateFields };