feat(services): Add services

Author: Gery Hirschfeld

src/App.ts

@@ -1,6 +1,5 @@
 // Core elements to get the server started
 import {
-    DB,
     Environment,
     Server,
     Logger,
@@ -18,8 +17,11 @@ import * as GraphQLHTTP from 'express-graphql';
 import { Exception } from './exceptions';
 import { Schema } from './schemas';
 import { RootValue } from './RootValue';
-import { Context, RepositoriesContext, DataLoadersContext } from './context';
-import { AuthorRepository, BookRepository } from './repositories';
+import {
+    Context,
+    DataLoadersContext,
+    ServicesContext
+} from './context';
 import { oauth } from './middlewares';
 
 
@@ -29,8 +31,6 @@ export class App {
 
     private log = Logger('app:main');
     private express: express.Application;
-    private repositoriesContext: RepositoriesContext;
-    private dataLoadersContext: DataLoadersContext;
 
     static getInstance(): App {
         if (!App.instance) {
@@ -41,8 +41,6 @@ export class App {
 
     constructor() {
         this.express = Server.init();
-        this.buildRepositoriesContext();
-        this.buildDataLoadersContext();
     }
 
     public main(): void {
@@ -73,9 +71,13 @@ export class App {
             this.log.debug('Setup GraphQLHTTP');
             // Creates a GraphQLHTTP per request
             GraphQLHTTP({
-                schema: Schema.getInstance().get(),
+                schema: Schema.getInstance(),
                 rootValue: new RootValue(),
-                context: new Context(req, res, this.repositoriesContext, this.dataLoadersContext),
+                context: new Context(
+                    req, res,
+                    DataLoadersContext.getInstance(),
+                    ServicesContext.getInstance()
+                ),
                 graphiql: Environment.getConfig().server.graphiql,
                 formatError: exception => ({
                     key: Exception.getKey(exception.message),
@@ -91,16 +93,4 @@ export class App {
         this.log.debug('Server was started on environment %s', Environment.getName());
     }
 
-    private buildRepositoriesContext(): void {
-        this.repositoriesContext = new RepositoriesContext()
-            .setAuthorRepository(new AuthorRepository(DB))
-            .setBookRepository(new BookRepository(DB));
-    }
-
-    private buildDataLoadersContext(): void {
-        this.dataLoadersContext = new DataLoadersContext()
-            .setAuthorDataLoader(this.repositoriesContext.AuthorRepository)
-            .setBookDataLoader(this.repositoriesContext.BookRepository);
-    }
-
 }

src/context/DataloadersContext.ts

@@ -8,9 +8,18 @@ const log = Logger('app:context:DataLoadersContext');
 
 export class DataLoadersContext {
 
+    static instance: DataLoadersContext;
+
     private authorDataLaoder: DataLoader<number, any>;
     private bookDataLaoder: DataLoader<number, any>;
 
+    static getInstance(): DataLoadersContext {
+        if (!DataLoadersContext.instance) {
+            DataLoadersContext.instance = new DataLoadersContext();
+        }
+        return DataLoadersContext.instance;
+    }
+
     public get AuthorDataLoader(): DataLoader<number, any> {
         return this.authorDataLaoder;
     }
@@ -20,13 +29,13 @@ export class DataLoadersContext {
     }
 
     public setAuthorDataLoader(authorRepository: AuthorRepository): DataLoadersContext {
-        this.authorDataLaoder = new DataLoader((ids: number[]) => authorRepository.findAuthorsByIds(ids));
+        this.authorDataLaoder = new DataLoader((ids: number[]) => authorRepository.findByIds(ids));
         log.debug('setAuthorDataLoader');
         return this;
     }
 
     public setBookDataLoader(bookRepository: BookRepository): DataLoadersContext {
-        this.bookDataLaoder = new DataLoader((ids: number[]) => bookRepository.findBooksByIds(ids));
+        this.bookDataLaoder = new DataLoader((ids: number[]) => bookRepository.findByIds(ids));
         log.debug('setBookDataLoader');
         return this;
     }

src/context/RepositoriesContext.ts

@@ -0,0 +1,44 @@
+import {
+    AuthorService,
+    BookService
+} from '../services';
+
+import { Logger } from '../core/logger';
+const log = Logger('app:context:ServicesContext');
+
+
+export class ServicesContext {
+
+    static instance: ServicesContext;
+
+    private authorService: AuthorService;
+    private bookService: BookService;
+
+    static getInstance(): ServicesContext {
+        if (!ServicesContext.instance) {
+            ServicesContext.instance = new ServicesContext();
+        }
+        return ServicesContext.instance;
+    }
+
+    public get AuthorService(): AuthorService {
+        return this.authorService;
+    }
+
+    public get BookService(): BookService {
+        return this.bookService;
+    }
+
+    public setAuthorService(authorService: AuthorService): ServicesContext {
+        this.authorService = authorService;
+        log.debug('setAuthorService');
+        return this;
+    }
+
+    public setBookService(bookService: BookService): ServicesContext {
+        this.bookService = bookService;
+        log.debug('setBookService');
+        return this;
+    }
+
+}

src/context/ServicesContext.ts

@@ -1,7 +1,7 @@
 import * as Express from 'express';
 
-import { RepositoriesContext } from './RepositoriesContext';
 import { DataLoadersContext } from './DataloadersContext';
+import { ServicesContext } from './ServicesContext';
 
 
 export class Context<A> {
@@ -16,8 +16,8 @@ export class Context<A> {
     constructor(
         private request: Express.Request,
         private repsonse: Express.Response,
-        private repositories: RepositoriesContext,
-        private dataLoaders: DataLoadersContext
+        private dataLoaders: DataLoadersContext,
+        private services: ServicesContext
     ) { }
 
     public get Args(): A {
@@ -32,14 +32,14 @@ export class Context<A> {
         return this.request;
     }
 
-    public get Repositories(): RepositoriesContext {
-        return this.repositories;
-    }
-
     public get DataLoaders(): DataLoadersContext {
         return this.dataLoaders;
     }
 
+    public get Services(): ServicesContext {
+        return this.services;
+    }
+
     public getLanguage(): string[] {
         return this.request.acceptsLanguages();
     }

src/context/context.ts

@@ -1,3 +1,33 @@
 export * from './Context';
-export * from './RepositoriesContext';
 export * from './DataloadersContext';
+export * from './ServicesContext';
+
+import { DB } from '../core/Database';
+import {
+    AuthorRepository,
+    BookRepository
+} from '../repositories';
+
+
+/**
+ * Dataloaders
+ */
+import { DataLoadersContext } from './DataloadersContext';
+DataLoadersContext.getInstance()
+    .setAuthorDataLoader(new AuthorRepository(DB))
+    .setBookDataLoader(new BookRepository(DB));
+
+
+/**
+ * Services
+ */
+import { ServicesContext } from './ServicesContext';
+
+import {
+    BookService,
+    AuthorService
+} from '../services';
+
+ServicesContext.getInstance()
+    .setBookService(new BookService(new BookRepository(DB)))
+    .setAuthorService(new AuthorService(new AuthorRepository(DB)));

src/context/index.ts

@@ -3,6 +3,10 @@ import { NotFoundException } from '../exceptions';
 
 export class Utils {
 
+    static isEmpty<T>(list: T[]): boolean {
+        return !Utils.hasResults(list);
+    };
+
     static hasResults<T>(list: T[]): boolean {
         return (typeof list === 'object' && !!list && list.length) ? list.length > 0 : false;
     };

src/core/Utils.ts

@@ -0,0 +1,13 @@
+// import { DI } from '../DI';
+
+// export const service = <T extends { new (...args: any[]): {} }>(constructor: T) => {
+
+//     console.log(constructor.name);
+//     console.log(constructor);
+
+//     DI.getInstance().register(constructor.name, constructor);
+
+//     return class extends constructor {
+
+//     };
+// };

src/core/anotations/service.ts

@@ -3,7 +3,7 @@ import { Exception } from './Exception';
 
 export class ValidationException extends Exception {
 
-    constructor(message: string) {
+    constructor(message?: string) {
         super(message);
         this.name = 'ValidationException';
         this.key = 'e_validation';