@gapi

Really easy GraphQL API framework build on top of NodeJS inspired by @Angular

Build with @rxdi - reactive Extension Dependency Injection Container working inside Browser and Node

Created to provide complex backend scalable applications with minimum effort.

For questions/issues you can write ticket here

Starting project for less than 1 minute via Gapi-CLI

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Heroku Ready!

Basic starter project has Heroku Easy Deploy Button!

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Amazon ServerLess Ready!

Check Example

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Part of the frameworks and techniques used without which Gapi would not exist :love_letter:

• Inversion of control pattern IOC explanation taken from this article:

IoC Containers are DI frameworks that can work outside of the programming language. In some you can configure which implementations to use in metadata files (e.g. XML) which are less invasive. With some you can do IoC that would normally be impossible like inject an implementation at pointcuts.

• Pointcuts - aspect-oriented computer programming

• Dependency Injection

• Typescript @Decorators

• @NodeJS

• @HAPI

• @ApolloGraphQL

• @Gapi-cli

• @RXJS

Advanced Starter Example and production build

• @Docker
• @PostgreSQL
• @RabbitMQ

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Video Tutorials

Starting tutorial with some explanation

Easy-starter-in-2-mins-installation-with-cli

Advanced-starter-in-2-mins-installation-with-cli

Start gapi a graphql server with Workers advanced(DOCKER)

Start gapi a graphql server with Workers in 2 minutes(DOCKER)

Integrated external modules:

@Gapi-Typescript-Sequelize

@Gapi-Angular-Client

@Gapi-Amqp-PubSub (Internally)

@Gapi-Onesignal-Notifications

@Gapi-Sequelize

@Gapi-voyager

Installation and basic examples:

To install this library, run:

1npm install @gapi/core

Simplest Gapi server

1import { CoreModule } from '@gapi/core';
2import { Controller, Module, BootstrapFramework } from '@rxdi/core';
3import { GapiObjectType, Query, Type } from '@rxdi/graphql';
4import { GraphQLScalarType, GraphQLInt, GraphQLNonNull } from 'graphql';
5
6@GapiObjectType()
7export class UserType {
8    readonly id: number | GraphQLScalarType = GraphQLInt;
9}
10
11@Controller()
12export class UserQueriesController {
13
14    @Type(UserType)
15    @Query({
16        id: {
17            type: new GraphQLNonNull(GraphQLInt)
18        }
19    })
20    findUser(root, { id }, context): UserType {
21        return {id: id};
22    }
23
24}
25
26@Module({
27    controllers: [UserQueriesController]
28})
29export class AppModule { }
30
31
32BootstrapFramework(AppModule, [CoreModule]).subscribe()

You need to create tsconfig.json with following content

1{
2    "compilerOptions": {
3        "emitDecoratorMetadata": true,
4        "experimentalDecorators": true
5    }
6}

Execute

1ts-node index.ts

Or execute the following command to set these options on runtime:

1export TS_NODE_COMPILER_OPTIONS='{"experimentalDecorators": true, "emitDecoratorMetadata": true}' &&
2ts-node index.ts --compilerOptions $TS_NODE_COMPILER_OPTIONS

To add configuration click here

With CLI

Next create project using CLI or read above how to bootstrap your custom application

Consuming gapi

First we need to install ts-node and nodemon globally

1npm install -g nodemon ts-node

Next install gapi globally using npm

1npm install @gapi/cli -g

To skip the following steps creating project and bootstraping from scratch you can type the following command:

It may take 20 seconds because it will install project dependencies.

Basic project

1gapi new my-project

Advanced Project

1gapi new my-project --advanced

Microservices Project

To create new basic project with microservices from scratch via CLI type:

1gapi new my-project --microservices

Serverless Basic Project

To create new basic serverless project without ORM from scratch via CLI type:

1gapi new my-project --serverless

Serverless Advanced Project

To create new advanced serverless sequelize project from scratch via CLI type:

1gapi new my-project --serverless-sequelize

Enter inside my-project and type:

1npm start

Open browser to

1http://localhost:9000/graphiql

Testing

To start developing with testing GAPI uses JEST and @gapi/cli is preconfigurated for your needs! :)

To run single test type:

1gapi test

Testing watch mode

Note: You need to start server before running tests

Note: Everytime you make change to server it will restart server and execute tests

Note: To add more tests just create e2e.spec.ts or unit.spec.ts somewhere inside the application

Start the application

1gapi start

Execute test with --watch argument

1gapi test --watch

You will end up with something like this

Custom logic before testing ( for example creating MOCK users to database before testing)

Create file test.ts inside root/src/test.ts with this content

Everytime you run test with --before argument it will set environment variable BEFORE_HOOK

1  if (process.env.BEFORE_HOOK) {
2    // do something here
3  }

Then execute tests with --before

1gapi test --before

This command will start root/src/test.ts file and will wait for process.exit(0) so you can customize your before logic check this link for reference

Unit Testing

1import { Container } from '@rxdi/core';
2import { AuthPrivateService } from './auth.service';
3
4const authService: AuthPrivateService = Container.get(AuthPrivateService);
5
6describe('Auth Service', () => {
7  it('unit: signJWTtoken => token : Should sucessfully sign jwt', async done => {
8        const token = authService.signJWTtoken({
9            email: 'dada@abv.bg',
10            id: 1,
11            scope: ['ADMIN']
12        });
13        expect(token).toBeTruthy();
14        const verifyedToken = authService.verifyToken(token);
15        expect(verifyedToken.email).toBe('dada@abv.bg');
16        expect(verifyedToken.id).toBe(1);
17        expect(verifyedToken.scope[0]).toBe('ADMIN');
18        done();
19  });
20});
21

Integrated testing utility inside basic and advanced examples E2E testing

Filepath: root/src/app/user/user-queries.controller.e2e.spec.ts

1import { Container } from '@rxdi/core';
2import { IQuery } from '../core/api-introspection/index';
3import { TestUtil } from '../core/test-util/testing.service';
4import { map } from 'rxjs/operators';
5
6const testUtil: TestUtil = Container.get(TestUtil);
7
8describe('User Queries Controller', () => {
9  it('e2e: queries => (findUser) : Should sucessfully find user', async done => {
10    testUtil.sendRequest<IQuery>({
11      query: `
12        query findUser($id: Int!) {
13            findUser(id: $id) {
14                id
15                settings {
16                    username
17                    firstname
18                }
19            }
20        }
21      `,
22      variables: {
23        id: 1
24      }
25    })
26      .pipe(
27        map(res => {
28            expect(res.success).toBeTruthy();
29            return res.data.findUser;
30        })
31      )
32      .subscribe(async res => {
33        expect(res.id).toBe(1);
34        expect(res.settings.username).toBe('o');
35        expect(res.settings.firstname).toBe('pesho');
36        done();
37      }, err => {
38        expect(err).toBe(null);
39        done();
40      });
41  });
42});
43

Filepath: root/src/app/core/test-util/testing.service.ts

1    disableAuthorization() {
2        this.tester = tester({ url: process.env.ENDPOINT_TESTING, contentType: 'application/json' });
3    }
4
5    enableAuthorization() {
6        this.tester = tester({ url: process.env.ENDPOINT_TESTING, contentType: 'application/json', authorization: process.env.TOKEN_TESTING});
7    }
8
9    sendRequest<T>(query: SendRequestQueryType): Observable<Response<T>> {
10        if (query.signiture) {
11            this.tester = tester({
12                url: process.env.ENDPOINT_TESTING,
13                contentType: 'application/json',
14                authorization: query.signiture.token
15            });
16        }
17        return from(this.tester(JSON.stringify(query)));
18    }

Effects

1import { Effect } from '@rxdi/core';
2import { OfType } from '@rxdi/graphql';
3import { EffectTypes } from '../core/api-introspection/EffectTypes';
4
5@Effect()
6export class UserEffects {
7
8    @OfType<EffectTypes>(EffectTypes.login)
9    findUser(result, payload, context) {
10        console.log(result, payload, context);
11    }
12
13}

How it works ?

When the application starts the whole schema is collected via Decorators applied inside GapiControllers.Now when we have our schema collected and bootstraping is done next step is to attach all BehaviorSubject Observables to particular resolver and from that step we got Type based string literal enums a.k.a Gapi Effects.They look like that:

1
2function strEnum<T extends string>(o: Array<T>): {[K in T]: K} {
3    return o.reduce((res, key) => {
4        res[key] = key;
5        return res;
6    }, Object.create(null));
7}
8export const EffectTypes = strEnum(['myevent',
9'login',
10'subscribeToUserMessagesBasic',
11'subscribeToUserMessagesWithFilter',
12'destroyUser',
13'updateUser',
14'addUser',
15'publishSignal']);
16export type EffectTypes = keyof typeof EffectTypes;
17

Import GapiEffect inside Module

1
2import { Module } from '@rxdi/core';
3import { UserQueriesController } from './user-queries.controller';
4import { UserSubscriptionsController } from './user-subscriptions.controller';
5import { UserMutationsController } from './user-mutations.controller';
6import { UserService } from './services/user.service';
7import { AnotherService } from './services/another.service';
8import { UserEffects } from './user.effects';
9
10@Module({
11    controllers: [
12        UserQueriesController,
13        UserSubscriptionsController,
14        UserMutationsController
15    ],
16    services: [
17        UserService,
18        AnotherService
19    ],
20    effects: [
21        UserEffects
22    ]
23})
24export class UserModule {}

If you want to create custom Effect for particular resolver you need to use @EffectName('myevent') Decorator takes String This decorator will override default event which is Name of the Method in this example will be findUser

1  @Type(UserType)
2  @EffectName('myevent')
3  @Query({
4    id: {
5      type: new GraphQLNonNull(GraphQLInt)
6    }
7  })
8  findUser(root, { id }, context) {
9    return {
10      id: 1
11    };
12  }

If you click Save app will automatically reload and you will have such a typing inside autogenerated EffectTypes from api-introspection Then you can lock it with new Typo generated "myevent"

1  @Type(UserType)
2  @EffectName(EffectTypes.myevent)
3  @Query({
4    id: {
5      type: new GraphQLNonNull(GraphQLInt)
6    }
7  })
8  findUser(root, { id }, context) {
9    return {
10      id: 1
11    };
12  }

Purpose of Effects is to create logic after particular resolver is triggered Successfully without thrown error for example:

• Create Analitics about API usage
• Publish message to RabbitMQ Queue and Consume it in another Funnel or Microservice
• Create After effect for UI/UX for example when user Login you can trigger some Push notification for user.
• etc.

Plugins

How to register plugin to the system. Difference between Plugin and Service is that system will trigger register method inside constructor if exist, else it will resolve OnInit and constructor properties. That way you can register your own plugins to the system after everything is bootstrapped. If you decide for example to return Promise on register and resolve it inside setTimeout(() =>resolve(data), 1000) the app will wait till the promise is resolved.

1
2import { Module, Plugin, Service, PluginInterface } from '@rxdi/core';
3import { HAPI_SERVER } from '@rxdi/hapi';
4import { Server } from 'hapi';
5
6@Service()
7export class TestService {
8  testMethod() {
9    return 'Hello world';
10  }
11}
12
13@Plugin()
14export class MyHapiPlugin implements PluginInterface {
15  name = 'MyPlugin';
16  version = '1.0.0';
17
18  constructor(
19    private testService: TestService,
20    @Inject(HAPI_SERVER) private server: Server
21  ) {}
22
23  async register() {
24    this.server.route({
25      method: 'GET',
26      path: '/test',
27      handler: this.handler.bind(this)
28    });
29  }
30
31  async handler(request, h) {
32    return this.testService.helloWorld();
33  }
34
35}
36
37@Module({
38    plugins: [MyHapiPlugin],
39    services: [TestService]
40})
41export class AppModule {}
42

ForRoot configuration for modules

1import { Module, ModuleWithServices, InjectionToken } from '@rxdi/core';
2import { of } from 'rxjs';
3
4@Service()
5export class MODULE_DI_CONFIG {
6    text: string = 'Hello world';
7}
8
9const MY_MODULE_CONFIG = new InjectionToken<MODULE_DI_CONFIG>('my-module-config');
10
11@Module({
12  imports: []
13})
14export class YourModule {
15  public static forRoot(): ModuleWithServices {
16    return {
17      module: YourModule,
18      services: [
19          { provide: MY_MODULE_CONFIG, useValue: { text: 'Hello world' } },
20          { provide: MY_MODULE_CONFIG, useClass: MODULE_DI_CONFIG },
21          { 
22            provide: MY_MODULE_CONFIG,
23            useFactory: () => ({text: 'Hello world'})
24          },
25          { 
26            provide: MY_MODULE_CONFIG,
27            lazy: true, // Will be evaluated and resolved if false will remain Promise
28            useFactory: async () => await Promise.resolve({text: 'Hello world'})
29          },
30          { 
31            provide: MY_MODULE_CONFIG,
32            lazy: true, // Will be evaluated and resolved if false will remain Observable
33            useFactory: () => of({text: 'Hello world'})
34          },
35          { 
36            // this example will download external module from link and save it inside node modules
37            // then will load it inside createUniqueHash token or MY_MODULE_CONFIG.
38            provide: MY_MODULE_CONFIG,
39            useDynamic: {
40                fileName: 'createUniqueHash',
41                namespace: '@helpers',
42                extension: 'js',
43                typings: '',
44                outputFolder: '/node_modules/',
45                link: 'https://ipfs.infura.io/ipfs/QmdQtC3drfQ6M6GFpDdrhYRKoky8BycKzWbTkc4NEzGLug'
46            }
47          }
48      ]
49    }
50  }
51}

(#amazon-serverless)

Amazon Serverless

Inside main.ts

1import { AppModule } from './app/app.module';
2import { BootstrapFramework, Container } from '@rxdi/core';
3import { FrameworkImports } from './framework-imports';
4import { format } from 'url';
5import { HAPI_SERVER } from '@rxdi/hapi';
6import { Server } from 'hapi';
7
8const App = BootstrapFramework(AuthMicroserviceModule, [FrameworkImports], { init: true }).toPromise();
9
10export const handler = async (event, context, callback) => {
11    const app = await App;
12    const url = format({
13        pathname: event.path,
14        query: event.queryStringParameters
15    });
16    const options = {
17        method: event.httpMethod,
18        url,
19        payload: event.body,
20        headers: event.headers,
21        validate: false
22    };
23    let res = {
24        statusCode: 502,
25        result: null
26    };
27    try {
28        res = await Container.get<Server>(HAPI_SERVER).inject(options);
29    } catch (e) {
30        console.error(JSON.stringify(e));
31    }
32    const headers = Object.assign({
33        'Access-Control-Allow-Origin': '*',
34        'Access-Control-Allow-Methods': 'DELETE,GET,HEAD,OPTIONS,PATCH,POST,PUT'
35    });
36    return {
37        statusCode: res.statusCode,
38        body: res.result,
39        headers
40    };
41};

Serverless-offline

If we want to use AWS Lambdas Offline we need to set RandomPort to true inside HapiConfig because HAPI will generate random PORT everytime and as far as i know lambas are independent server which will be started everytime when someone execute that particular function.So when running offline it will not say that port 9000 is opened with another server.

1import { AppModule } from './app/app.module';
2import { BootstrapFramework } from '@rxdi/core';
3import { CoreModule } from '@gapi/core';
4
5const GapiCoreModule = CoreModule.forRoot({
6    server: {
7        randomPort: true,
8        hapi: {
9            port: 9000
10        }
11    },
12    graphql: {
13        path: '/graphql',
14        openBrowser: false,
15        writeEffects: false,
16        graphiQlPath: '/graphiql',
17        graphiqlOptions: {
18            endpointURL: '/graphql',
19            subscriptionsEndpoint: `ws://localhost:9000/subscriptions`,
20            websocketConnectionParams: {
21                token: process.env.GRAPHIQL_TOKEN
22            }
23        },
24        graphqlOptions: {
25            schema: null
26        }
27    },
28});
29BootstrapFramework(AppModule, [GapiCoreModule], {
30    init: false,
31    initOptions: {
32        effects: true,
33        plugins: true,
34        services: true,
35        controllers: true
36    },
37    logger: {
38        logging: true,
39        date: true,
40        exitHandler: true,
41        fileService: true,
42        hashes: true
43    }
44})
45.subscribe(
46    () => console.log('Started!'),
47    (e) => console.error(e)
48);

Lambdas cannot use Typescript so we need to compile our application to es6 as commonjs module

1tsc

Create serverless.yml

1service: gapi-serverless
2provider:
3  name: aws
4  runtime: nodejs8.10
5  stage: development
6  profile: default
7  region: us-east-2
8
9functions:
10  root:
11    handler: src/main.handler
12    events:
13      - http:
14          path: "/{proxy+}"
15          method: any
16          cors: true
17          integration: lambda-proxy
18
19plugins:
20  - serverless-offline
21

Then we can run

1serverless deploy

Later you can create PROXY server and map all existing Lambdas as a single GRAPHQL Schema

1import { Module } from '@rxdi/core';
2import { MicroserviceModule } from '@gapi/microservices';
3import { CoreModule } from './core/core.module';
4
5@Module({
6  imports: [
7    CoreModule,
8    MicroserviceModule.forRoot([
9      {name: 'microservice1', link: 'https://hkzdqnc1i2.execute-api.us-east-2.amazonaws.com/development/graphql'}
10    ]),
11  ]
12})
13export class AppModule {}
14

(#gapi-configuration)

Configuration

Since 1.0.0 version @gapi micrated to @rxdi there is a little changes which are with Configuration @gapi now uses @rxdi/core infrastructure so it is a Framework created on top of it This @gapi/core module is wrapper for 3 modules from @rxdi infrastructure: @rxdi/graphql, @rxdi/graphql-pubsub, @rxdi/hapi When you install @gapi/core automatically will be installed these 3 modules and inside of @gapi/core module there is a Default configuration for CoreModule which this module exports { CoreModule } example:

1const DEFAULT_CONFIG = {
2    server: {
3        hapi: {
4            port: 9000
5        },
6    },
7    graphql: {
8        path: '/graphql',
9        openBrowser: true,
10        writeEffects: true,
11        graphiql: true,
12        graphiQlPlayground: false,
13        graphiQlPath: '/graphiql',
14        watcherPort: '',
15        graphiqlOptions: {
16            endpointURL: '/graphql',
17            subscriptionsEndpoint: `${
18                process.env.GRAPHIQL_WS_SSH ? 'wss' : 'ws'
19                }://${process.env.GRAPHIQL_WS_PATH || 'localhost'}${
20                process.env.DEPLOY_PLATFORM === 'heroku'
21                    ? ''
22                    : `:${process.env.API_PORT ||
23                    process.env.PORT}`
24                }/subscriptions`,
25            websocketConnectionParams: {
26                token: process.env.GRAPHIQL_TOKEN
27            }
28        },
29        graphqlOptions: {
30            schema: null
31        }
32    },
33};
34...

Full example can be checked here

Based on that change if we want to not use default configuration instead of this

1BootstrapFramework(AppModule, [CoreModule]).subscribe()

We need to add more complex configuration and call it framework-imports where our configuration will live This module will be imported before AppModule will bootstrap.

1import { CoreModule, Module } from '@gapi/core';
2import { AuthService } from './app/core/services/auth/auth.service';
3import { AuthModule } from '@gapi/auth';
4import { readFileSync } from 'fs';
5
6@Module({
7    imports: [
8        AuthModule.forRoot({
9            algorithm: 'HS256',
10            cert: readFileSync('./cert.key'),
11            cyper: {
12                algorithm: 'aes256',
13                iv: 'Jkyt1H3FA8JK9L3B',
14                privateKey: '8zTVzr3p53VC12jHV54rIYu2545x47lA'
15            }
16        }),
17        CoreModule.forRoot({
18            server: {
19                hapi: {
20                    port: process.env.API_PORT || process.env.PORT || 9000
21                }
22            },
23            pubsub: {
24                authentication: AuthService
25            },
26            graphql: {
27                path: process.env.GRAPHQL_PATH,
28                openBrowser: process.env.OPEN_BROWSER === 'true' ? true : false,
29                watcherPort: 8967,
30                writeEffects: process.env.WRITE_EFFECTS === 'true' ? true : false,
31                graphiql: process.env.GRAPHIQL === 'true' ? true : false,
32                graphiQlPlayground: process.env.ENABLE_GRAPHIQL_PLAYGROUND === 'true' ? true : false,
33                graphiQlPath: process.env.GRAPHIQL_PATH,
34                authentication: AuthService,
35                graphiqlOptions: {
36                    endpointURL: process.env.GRAPHQL_PATH,
37                    passHeader: `'Authorization':'${process.env.GRAPHIQL_TOKEN}'`,
38                    subscriptionsEndpoint: `${process.env.GRAPHIQL_WS_SSH ? 'wss' : 'ws'}://${process.env.GRAPHIQL_WS_PATH || 'localhost'}${process.env.DEPLOY_PLATFORM === 'heroku'
39                        ? ''
40                        : `:${process.env.API_PORT ||
41                            process.env.PORT}`}/subscriptions`,
42                    websocketConnectionParams: {
43                        token: process.env.GRAPHIQL_TOKEN
44                    }
45                },
46                graphqlOptions: {
47                    schema: null
48                }
49            },
50        }),
51
52    ]
53})
54export class FrameworkImports {}
55

Now you can import FrameworkImports

1import { BootstrapFramework } from '@rxdi/core';
2import { FrameworkImports } from './framework-imports';
3import { AppModule } from './app/app.module';
4
5BootstrapFramework(AppModule, [FrameworkImports]).subscribe()

Docker

Following commands will start RabbitMQ, PostgreSQL, API, NGINX as a services and you need DOCKER installed on your system!

More information you can find inside project basic or advanced Documentation

API will be served on https://localhost:80 and https://localhost:80/subscriptions

Your custom certificates can be added here "root/nginx/certs/cert.key" "root/nginx/certs/cert.pem"

To build project with Docker type:

1gapi app build

To start project with Docker type:

1gapi app start

To stop project type:

1gapi app stop

Workers

All workers will be mapped as Proxy and will be reverted to https://localhost:80 and https://localhost:80/subscriptions

So you don't have to worry about if some of your workers stopped responding

Todo: Create monitoring for all workers and main API

To start workers type:

1gapi workers start

To stop workers type:

1gapi workers stop

Creating application from scratch and custom bootstrapping Without CLI

Create folder structure like this root/src/app

Create AppModule like the example above

Inject UserModule into imports inside AppModule

Folder root/src/app/app.module.ts

1import { Module } from '@rxdi/core';
2import { UserModule } from './user/user.module';
3import { CoreModule } from './core/core.module';
4
5@Module({
6    imports: [
7        UserModule,
8        CoreModule
9    ]
10})
11export class AppModule { }
12

Create module UserModule in where we will Inject our created controllers

Folder root/src/app/user/user.module.ts

1
2import { Module } from '@rxdi/core';
3import { UserQueriesController } from './user-queries.controller';
4import { UserSubscriptionsController } from './user-subscriptions.controller';
5import { UserMutationsController } from './user-mutations.controller';
6import { UserService } from './services/user.service';
7import { AnotherService } from './services/another.service';
8import { UserEffect } from './user.effect';
9
10@Module({
11    controllers: [
12        UserQueriesController,
13        UserSubscriptionsController,
14        UserMutationsController
15    ],
16    services: [
17        UserService,
18        AnotherService
19    ],
20    effects: [
21        UserEffect
22    ]
23})
24export class UserModule {}

Define UserType schema

Folder root/src/user/type/user.type.ts

You can customize every resolver from schema and you can create nested schemas with @GapiObjectType decorator

User Schema

Note that you can modify response result via @Resolve('key for modifier defined inside constructor')

Root is the value of previews resolver so for example root.id = '1';

When you return some value from @Resolve decorator root.id will be replaced with returned value so it will be 5 in the example

If you remove @Resolve decorator it will be passed value returned from the first root resolver

1import { GapiObjectType, Resolve, InjectType } from '@rxdi/graphql';
2import { GraphQLScalarType, GraphQLInt, GraphQLString } from 'graphql';
3import { UserSettings } from './user.settings';
4
5@GapiObjectType()
6export class UserType {
7    readonly id: number | GraphQLScalarType = GraphQLInt;
8    readonly email: string | GraphQLScalarType = GraphQLString;
9    readonly type: string | GraphQLScalarType =  GraphQLString;
10    readonly password: string | GraphQLScalarType =  GraphQLString;
11    readonly name: string | GraphQLScalarType =  GraphQLString;
12    readonly settings: UserSettings = InjectType(UserSettings);
13
14    @Resolve('id')
15    getId?(root, payload, context) {
16        return 1;
17    }
18}

UserSettings Schema

1import { Injector } from '@rxdi/core';
2import { GapiObjectType, Resolve } from '@rxdi/graphql';
3import { AnotherService } from '../services/another.service';
4import { GraphQLScalarType, GraphQLBoolean } from 'graphql';
5
6@GapiObjectType()
7export class UserSettings {
8
9    @Injector(AnotherService) private anotherService?: AnotherService;
10
11    readonly sidebar: boolean | GraphQLScalarType = GraphQLBoolean;
12
13    @Resolve('sidebar')
14    async getSidebar?(root, payload, context) {
15        return await this.anotherService.returnTrueAsync();
16    }
17
18}

UserMessage Schema for Subscriptions

1import { GapiObjectType } from '@rxdi/graphql';
2import { GraphQLScalarType, GraphQLString } from 'graphql';
3
4@GapiObjectType()
5export class UserMessage {
6    readonly message: string | GraphQLScalarType = GraphQLString;
7}

UserToken

1import { GapiObjectType, InjectType } from '@rxdi/graphql';
2import { UserType } from './user.type';
3import { GraphQLScalarType, GraphQLString } from 'graphql';
4
5@GapiObjectType()
6export class UserTokenType {
7    readonly token: string | GraphQLScalarType = GraphQLString;
8    readonly user: UserType = InjectType(UserType);
9}

Query

Folder root/src/user/query.controller.ts

1import { Controller } from '@rxdi/core';
2import { Type, Query, Public } from '@rxdi/graphql';
3import { GraphQLNonNull, GraphQLInt, GraphQLString } from 'graphql';
4import { UserService } from './services/user.service';
5import { UserType } from './types/user.type';
6import { UserTokenType } from './types/user-login.type';
7import { AuthPrivateService } from '../core/services/auth/auth.service';
8import { IUserType, IUserTokenType } from '../core/api-introspection/index';
9
10@Controller()
11export class UserQueriesController {
12
13    constructor(
14        private userService: UserService,
15        private authService: AuthPrivateService
16    ) { }
17
18    @Type(UserType)
19    @Public()
20    @Query({
21        id: {
22            type: new GraphQLNonNull(GraphQLInt)
23        }
24    })
25    findUser(root, { id }, context): IUserType {
26        return this.userService.findUser(id);
27    }
28
29    @Type(UserTokenType)
30    @Public()
31    @Query({
32        email: {
33            type: new GraphQLNonNull(GraphQLString)
34        },
35        password: {
36            type: new GraphQLNonNull(GraphQLString)
37        }
38    })
39    login(root, { email, password }, context) {
40        let credential: IUserTokenType;
41
42        // Find user from database
43        const user = <IUserType>{
44            id: 1,
45            email: email,
46            type: 'ADMIN',
47            settings: {
48                sidebar: true
49            },
50            password: this.authService.encryptPassword(password),
51            name: 'Test Testov'
52        };
53
54        if (this.authService.decryptPassword(user.password) === password) {
55            credential = {
56                user: user,
57                token: this.authService.signJWTtoken({
58                    email: user.email,
59                    id: user.id,
60                    scope: [user.type]
61                })
62            };
63        } else {
64            throw new Error('missing-username-or-password');
65        }
66        return credential;
67    }
68
69}
70

Mutation

Folder root/src/user/mutation.controller.ts

1import { Controller } from '@rxdi/core';
2import { UserService } from './services/user.service';
3import { UserType } from './types/user.type';
4import { UserMessage } from './types/user-message.type';
5import { IUserType } from '../core/api-introspection';
6import { PubSubService } from '@rxdi/graphql-pubsub';
7import { Scope, Type, Mutation, Public } from '@rxdi/graphql';
8import { GraphQLNonNull, GraphQLString, GraphQLInt } from 'graphql';
9
10@Controller()
11export class UserMutationsController {
12
13    constructor(
14        private userService: UserService,
15        private pubsub: PubSubService
16    ) {}
17
18    @Scope('ADMIN')
19    @Type(UserMessage)
20    @Public()
21    @Mutation({
22        message: {
23            type: new GraphQLNonNull(GraphQLString)
24        },
25        signal: {
26            type: new GraphQLNonNull(GraphQLString)
27        },
28    })
29    publishSignal(root, { message, signal }, context): UserMessage  {
30        console.log(`${signal} Signal Published message: ${message} by ${context.email}`);
31        this.pubsub.publish(signal, `${signal} Signal Published message: ${message} by ${context.email}`);
32        return {message};
33    }
34
35    @Scope('ADMIN')
36    @Type(UserType)
37    @Mutation({
38        id: {
39            type: new GraphQLNonNull(GraphQLInt)
40        }
41    })
42    deleteUser(root, { id }, context): IUserType  {
43        return this.userService.deleteUser(id);
44    }
45
46    @Scope('ADMIN')
47    @Type(UserType)
48    @Mutation({
49        id: {
50            type: new GraphQLNonNull(GraphQLInt)
51        }
52    })
53    updateUser(root, { id }, context): IUserType {
54        return this.userService.updateUser(id);
55    }
56
57    @Scope('ADMIN')
58    @Type(UserType)
59    @Mutation({
60        id: {
61            type: new GraphQLNonNull(GraphQLInt)
62        }
63    })
64    addUser(root, { id }, context): IUserType  {
65        return this.userService.addUser(id);
66    }
67
68}
69
70

Subscription

Folder root/src/user/user.subscription.controller.ts

1
2import { Controller } from '@rxdi/core';
3import { Type, Scope, Public } from '@rxdi/graphql';
4import { withFilter } from 'graphql-subscriptions';
5import { GraphQLNonNull, GraphQLInt } from 'graphql';
6import { PubSubService, Subscribe, Subscription } from '@rxdi/graphql-pubsub';
7import { UserMessage } from './types/user-message.type';
8
9@Controller()
10export class UserSubscriptionsController {
11
12    constructor(
13        private pubsub: PubSubService
14    ) {}
15
16    @Scope('ADMIN')
17    @Type(UserMessage)
18    @Public()
19    @Subscribe((self: UserSubscriptionsController) => self.pubsub.asyncIterator('CREATE_SIGNAL_BASIC'))
20    @Subscription()
21    subscribeToUserMessagesBasic(message): UserMessage {
22        return { message };
23    }
24
25    @Scope('ADMIN')
26    @Type(UserMessage)
27    @Subscribe(
28        withFilter(
29            (self: UserSubscriptionsController) => self.pubsub.asyncIterator('CREATE_SIGNAL_WITH_FILTER'),
30            (payload, {id}, context) => {
31                console.log('Subscribed User: ', id, JSON.stringify(context));
32                return true;
33            }
34        )
35    )
36    @Subscription({
37        id: {
38            type: new GraphQLNonNull(GraphQLInt)
39        }
40    })
41    subscribeToUserMessagesWithFilter(message): UserMessage {
42        return { message };
43    }
44
45}
46
47

Example subscription query Basic

1subscription {
2  subscribeToUserMessagesBasic {
3    message
4  }
5}

Example subscription query WithFilter

1subscription {
2  subscribeToUserMessagesWithFilter(id:1)  {
3    message
4  }
5}

Create Service with @Service decorator somewhere

Folder root/src/user/services/user.service.ts

1
2import { Service } from '@rxdi/core';
3import { IUserType } from '../../core/api-introspection';
4
5@Service()
6export class AnotherService {
7    trimFirstLetter(username: string): string {
8        return username.charAt(1);
9    }
10
11    trimFirstLetterAsync(username): Promise<string> {
12        return Promise.resolve(this.trimFirstLetter(username));
13    }
14
15    returnTrueAsync() {
16        return Promise.resolve(true);
17    }
18}
19
20@Service()
21export class UserService {
22    constructor(
23    ) { }
24
25    findUser(id: number): IUserType {
26        return {
27            id: 1,
28            email: 'test@gmail.com',
29            type: 'ADMIN',
30            password: '123456',
31            name: 'Pesho',
32            settings: {
33                sidebar: true
34            }
35        };
36    }
37
38    addUser(id: number): IUserType {
39        return {
40            id: 1,
41            email: 'test@gmail.com',
42            type: 'ADMIN',
43            password: '123456',
44            name: 'Pesho',
45            settings: {
46                sidebar: true
47            }
48        };
49    }
50
51    deleteUser(id: number): IUserType {
52        return {
53            id: 1,
54            email: 'test@gmail.com',
55            type: 'ADMIN',
56            password: '123456',
57            name: 'Pesho',
58            settings: {
59                sidebar: true
60            }
61        };
62    }
63
64    updateUser(id): IUserType {
65        return {
66            id: 1,
67            email: 'test@gmail.com',
68            type: 'ADMIN',
69            password: '123456',
70            name: 'Pesho',
71            settings: {
72                sidebar: true
73            }
74        };
75    }
76
77}

Finally Bootstrap your application

Folder root/src/main.ts

1import { AppModule } from './app/app.module';
2import { BootstrapFramework } from '@rxdi/core';
3import { CoreModule } from '@gapi/core';
4
5BootstrapFramework(AppModule, [CoreModule], {
6    init: false,
7    initOptions: {
8        effects: true,
9        plugins: true,
10        services: true,
11        controllers: true
12    },
13    logger: {
14        logging: true,
15        date: true,
16        exitHandler: true,
17        fileService: true,
18        hashes: true
19    }
20})
21.subscribe(
22    () => console.log('Started!'),
23    (e) => console.error(e)
24);

Start your application using following command inside root folder of the repo

Important the script will search main.ts inside root/src/main.ts where we bootstrap our module bellow

gapi start

Basic authentication

Create Core Module

Folder root/src/app/core/core.module.ts

1
2import { Module } from '@rxdi/core';
3import { AuthPrivateService } from './services/auth/auth.service';
4
5@Module({
6    services: [
7        AuthPrivateService
8    ]
9})
10export class CoreModule {}

Create PrivateAuthService @Service() this is complete Subscriptions Query Mutation Authentication via single method "validateToken()"

Above there are example methods from GapiAuth module which are provided on air for encrypting and decrypting user password

Folder root/src/app/core/services/auth/auth.service

1
2import { Service } from '@rxdi/core';
3import * as Boom from 'boom';
4
5export interface UserInfo {
6    scope: ['ADMIN', 'USER'];
7    type: 'ADMIN' | 'USER';
8    iat: number;
9}
10
11@Service()
12export class AuthPrivateService {
13
14    constructor(
15        // private authService: AuthService,
16        // private connectionHookService: ConnectionHookService
17    ) {
18        // this.connectionHookService.modifyHooks.onSubConnection = this.onSubConnection.bind(this);
19        // this.authService.modifyFunctions.validateToken = this.validateToken.bind(this);
20    }
21
22    onSubConnection(connectionParams): UserInfo {
23        if (connectionParams.token) {
24            return this.validateToken(connectionParams.token, 'Subscription');
25        } else {
26            throw Boom.unauthorized();
27        }
28    }
29
30    validateToken(token: string, requestType: 'Query' | 'Subscription' = 'Query'): UserInfo {
31        const user = <UserInfo>this.verifyToken(token);
32        user.type = user.scope[0];
33        console.log(`${requestType} from: ${JSON.stringify(user)}`);
34        if (user) {
35            return user;
36        } else {
37            throw Boom.unauthorized();
38        }
39    }
40
41    verifyToken(token: string): any {
42        // return this.authService.verifyToken(token);
43        return token;
44    }
45
46    signJWTtoken(tokenData: any): any {
47        // return this.authService.sign(tokenData);
48        return tokenData;
49    }
50
51    issueJWTToken(tokenData: any) {
52        // const jwtToken = this.authService.sign({
53        //     email: '',
54        //     id: 1,
55        //     scope: ['ADMIN', 'USER']
56        // });
57        // return jwtToken;
58    }
59
60    decryptPassword(password: string): any {
61        // return this.authService.decrypt(password);
62        return password;
63    }
64
65    encryptPassword(password: string): any {
66        // return this.authService.encrypt(password);
67        return password;
68    }
69
70}
71

Final import CoreModule inside AppModule

1import { Module } from '@rxdi/core';
2import { UserModule } from './user/user.module';
3import { UserService } from './user/services/user.service';
4import { CoreModule } from './core/core.module';
5
6@Module({
7    imports: [
8        UserModule,
9        CoreModule
10    ]
11})
12export class AppModule { }

Dependency Injection

1
2import { Module, InjectionToken } from '@rxdi/core';
3import { UserModule } from './user/user.module';
4import { CoreModule } from './core/core.module';
5
6class UserId {
7    id: number;
8}
9
10export const UserIdToken = new InjectionToken<UserId>('UserId');
11
12@Module({
13    imports: [
14        UserModule,
15        CoreModule
16    ],
17    services: [
18        {
19            provide: 'UserId',
20            useValue: {id: 1}
21        },
22        {
23            provide: UserIdToken,
24            useFactory: () => {
25                return {id: 1};
26            }
27        },
28        {
29            provide: UserIdToken,
30            useClass: UserId
31        }
32    ]
33})
34export class AppModule { }

1@Controller()
2export class UserQueriesController {
3    constructor(
4        @Inject('UserId') private userId: {id: number}, // Value injection
5        @Inject(UserIdToken) private userId: UserId, // Token injection
6        @Inject(UserIdToken) private userId: UserId, // Class injection
7    ) {
8        console.log(this.userId.id);
9        // Will print 1
10    }
11}

You can put also Observable as a value

1import { Module } from '@rxdi/core';
2import { UserModule } from './user/user.module';
3import { CoreModule } from './core/core.module';
4import { BehaviorSubject } from 'rxjs/BehaviorSubject';
5
6@Module({
7    imports: [
8        UserModule,
9        CoreModule
10    ],
11    services: [
12        {
13            provide: 'Observable',
14            useValue: new BehaviorSubject(1)
15        }
16    ]
17})
18export class AppModule { }

Then inject this service somewhere in your application

1import { Controller } from '@rxdi/core';
2import { BehaviorSubject } from 'rxjs/BehaviorSubject';
3import { PubSubService } from '@rxdi/graphql-pubsub';
4
5@Controller()
6export class UserSubscriptionsController {
7
8    constructor(
9        @Inject('Observable') private observable: BehaviorSubject<number>,
10        private pubsub: PubSubService
11    ) {
12        this.observable.subscribe(() => this.pubsub.publish('CREATE_SIGNAL_BASIC', `Signal Published message: ${this.observable.getValue()}`));
13    }
14}

Then you can put it inside another service and emit values

1import { Service, Inject } from '@rxdi/core';
2import { BehaviorSubject } from 'rxjs/BehaviorSubject';
3import { TimerObservable } from 'rxjs/observable/TimerObservable';
4
5@Service()
6export class UserService {
7    constructor(
8        @Inject('Observable') private observable: BehaviorSubject<number>
9    ) {
10        TimerObservable.create(0, 1000).subscribe((t) => this.observable.next(t))
11    }

Cross reference circular dependency

1import { UserService } from './user.service';
2
3@Service()
4export class AnotherService {
5    @Inject(() => UserService) private userService: UserService

1import { AnotherService } from './another.service';
2
3@Service()
4export class UserService {
5    @Inject(() => AnotherService) private anotherService: AnotherService

You can see the subscription when you subscribe to basic chanel inside GraphiQL dev panel

1subscription {
2  subscribeToUserMessagesBasic {
3    message
4  }
5}

The result will be

1{
2  "subscribeToUserMessagesBasic": {
3    "message": "Signal Published message: 495"
4  }
5}

Complex schema object with nested schemas of same type

1import { GapiObjectType, InjectType, Resolve, Type } from '@rxdi/graphql';
2import { GraphQLGapiObjectType, GraphQLString, GraphQLInt, GraphQLList, GraphQLBoolean, GraphQLScalarType } from "graphql";
3
4@GapiObjectType()
5export class UserSettingsType {
6    readonly id: number | GraphQLScalarType = GraphQLInt;
7    readonly color: string | GraphQLScalarType = GraphQLString;
8    readonly language: string | GraphQLScalarType = GraphQLString;
9    readonly sidebar: boolean | GraphQLScalarType = GraphQLBoolean;
10}
11
12@GapiObjectType()
13export class UserWalletSettingsType {
14    readonly type: string | GraphQLScalarType = GraphQLString;
15    readonly private: string | GraphQLScalarType = GraphQLString;
16    readonly security: string | GraphQLScalarType = GraphQLString;
17    readonly nested: UserSettingsType = InjectType(UserSettingsType);
18    readonly nested2: UserSettingsType = InjectType(UserSettingsType);
19    readonly nested3: UserSettingsType = InjectType(UserSettingsType);
20
21    // If you want you can change every value where you want with @Resolve decorator
22    @Resolve('type')
23    changeType(root, args, context) {
24        return root.type + ' new-type';
25    }
26
27    // NOTE: you can name function methods as you wish can be Example3 for example important part is to define 'nested3' as a key to map method :)
28    @Resolve('nested3')
29    Example3(root, args, context) {
30        // CHANGE value of object type when returning
31        // UserSettingsType {
32        //     "id": 1,
33        //     "color": "black",
34        //     "language": "en-US",
35        //     "sidebar": true
36        // }
37        // root.nested3.id
38        // root.nested3.color
39        // root.nested3.language
40        // root.nested3.sidebar
41        return root.nested3;
42    }
43}
44
45
46@GapiObjectType()
47export class UserWalletType {
48    readonly id: number | GraphQLScalarType = GraphQLInt;
49    readonly address: string | GraphQLScalarType = GraphQLString;
50    readonly settings: string | UserWalletSettingsType = InjectType(UserWalletSettingsType);
51}
52
53
54@GapiObjectType()
55export class UserType {
56    readonly id: number | GraphQLScalarType = GraphQLInt;
57    readonly email: string | GraphQLScalarType = GraphQLString;
58    readonly firstname: string | GraphQLScalarType = GraphQLString;
59    readonly lastname: string | GraphQLScalarType = GraphQLString;
60    readonly settings: string | UserSettingsType = InjectType(UserWalletSettingsType);
61    readonly wallets: UserWalletType = new GraphQLList(InjectType(UserWalletType));
62}
63

When you create such a query from graphiql dev tools

1query {
2  findUser(id:1) {
3    id
4    email
5     firstname
6     lastname
7    settings {
8      id
9      color
10      language
11      sidebar
12    }
13    wallets {
14      id
15      address
16      settings {
17        type
18        private
19        security
20        nested {
21          id
22          color
23          language
24          sidebar
25        }
26        nested2 {
27          id
28          color
29          language
30          sidebar
31        }
32        nested3 {
33          id
34          color
35          language
36          sidebar
37        }
38      }
39    }
40  }
41}
42

This query respond to chema above

1
2   findUser(id: number): UserType {
3        return {
4            id: 1,
5            email: "kristiqn.tachev@gmail.com",
6            firstname: "Kristiyan",
7            lastname: "Tachev",
8            settings: {
9                id: 1,
10                color: 'black',
11                language: 'en-US',
12                sidebar: true
13            },
14            wallets: [{
15                id: 1, address: 'dadadada', settings: {
16                    type: "ethereum",
17                    private: false,
18                    security: "TWO-STEP",
19                    nested: {
20                        id: 1,
21                        color: 'black',
22                        language: 'en-US',
23                        sidebar: true
24                    },
25                    nested2: {
26                        id: 1,
27                        color: 'black',
28                        language: 'en-US',
29                        sidebar: true
30                    },
31                    nested3: {
32                        id: 1,
33                        color: 'black',
34                        language: 'en-US',
35                        sidebar: true
36                    },
37                    nested4: {
38                        id: 1,
39                        color: 'black',
40                        language: 'en-US',
41                        sidebar: true
42                    },
43                    
44                }
45            }]
46        };
47    }

The return result from graphql QL will be

1{
2  "data": {
3    "findUser": {
4      "id": 1,
5      "email": "kristiqn.tachev@gmail.com",
6      "firstname": "Kristiyan",
7      "lastname": "Tachev",
8      "settings": {
9        "id": 1,
10        "color": "black",
11        "language": "en-US",
12        "sidebar": true
13      },
14      "wallets": [
15        {
16          "id": 1,
17          "address": "dadadada",
18          "settings": {
19            "type": "ethereum new-type",
20            "private": "false",
21            "security": "TWO-STEP",
22            "nested": {
23              "id": 1,
24              "color": "black",
25              "language": "en-US",
26              "sidebar": true
27            },
28            "nested2": {
29              "id": 1,
30              "color": "black",
31              "language": "en-US",
32              "sidebar": true
33            },
34            "nested3": {
35              "id": 1,
36              "color": "black",
37              "language": "en-US",
38              "sidebar": true
39            }
40          }
41        }
42      ]
43    }
44  }
45}

Decorators

All Gapi Decorators

@Query - Define Query object added above method inside @Controller

@Mutation - Define Mutation object added above method inside @Controller

@Subscription - Define Subscription object added above method inside @Controller

@Subscribe - It will be used with @Subscription Decorator and it takes PubSubIterator function @Subscribe(() => UserSubscriptionsController.pubsub.asyncIterator('CREATE_SIGNAL_BASIC')) can be used also withFilter

1    @Subscribe(
2        withFilter(
3            (self: UserSubscriptionsController) => self.pubsub.asyncIterator('CREATE_SIGNAL_WITH_FILTER'),
4            (payload, {id}, context) => {
5                console.log('User trying to subscribe: ', id, JSON.stringify(context));
6                // if user passes your expression it will be subscribed to this subscription
7                return id !== context.id;
8            }
9        )
10    )
11    @Subscription()
12    subscribeToUserMessagesWithFilter(message): UserMessage {
13        return { message };
14    }

@Public - Works with (@Query, @Mutation, Subscription) adds property "public = true" will make this particular resolver Public without authentication

@Scope - Can take arguments like what kind of User can use this Resolver @scope('ADMIN', 'USER', 'SALES')

@Type - Works with (@Query, @Mutation, Subscription) passing ObjectType class here for example UserType this is internally new GraphQLObjectType

@GapiObjectType - Internally is using new GraphQLObjectType() adding name of the class as a {name: constructor.name} can take {name: 'YourCustomName'} as argument also the same Object type can be used for generating new GraphQLInputObjectType when passing {input: true} used for Arguments

@Resolve - This is used internally inside GapiObjectType and it is related with modifying return result from GraphQL like in the following example

1@GapiObjectType()
2export class UserType {
3    id: number | GraphQLScalarType = GraphQLInt;
4    
5    @Resolve('id')
6    getId?(root, payload, context) {
7        return 5;
8    }
9}
10

Important part is that getId? method needs to be OPTIONAL because it will be part of the Interface defined by the class UserType so everywhere if you use UserType it will ask you to add getId as a function but we just want to modify the return result from Schema with Resolve method decorator.

@Controller - It will define Controllers inside Gapi Application you can have as many as you wish controllers just when you are ready import them inside @Module({controllers: ...CONTROLLERS})

@Guard - this decorator will add Guards to particular resolvers can be used this way:

1import { Controller } from '@rxdi/core';
2import { Type, Query, Guard } from '@rxdi/graphql';
3import { UserService } from './services/user.service';
4import { UserListType } from './types/user-list.type';
5import { AdminOnly } from '../core/guards/admin-only.guard';
6
7@Controller()
8export class UserQueriesController {
9
10    constructor(
11        private userService: UserService
12    ) { }
13
14    @Type(UserListType)
15    @Guard(AdminOnly)
16    @Query()
17    listUsers() {
18        return this.userService.findAll();
19    }
20
21}
22
23

Or you can apply them globaly to controller like this

1
2import { Query, GraphQLControllerOptions, InjectType } from '@rxdi/graphql';
3import { UserService } from './services/user.service';
4import { UserListType } from './types/user-list.type';
5import { AdminOnly } from '../core/guards/admin-only.guard';
6
7@Controller<GraphQLControllerOptions>({
8    guards: [AdminOnly],
9    type: InjectType(UserListType)
10})
11export class UserQueriesController {
12
13    constructor(
14        private userService: UserService
15    ) { }
16
17    @Query()
18    listUsers() {
19        return this.userService.findAll();
20    }
21}
22

The basic guard example:

1import { Service, CanActivateResolver, GenericGapiResolversType } from '@gapi/core';
2import { ENUMS } from '../enums';
3import { UserType } from '../../user/types/user.type';
4
5@Service()
6export class AdminOnly implements CanActivateResolver {
7    canActivate(
8        context: UserType,
9        payload,
10        descriptor: GenericGapiResolversType
11    ) {
12        return context.type === 'ADMIN';
13    }
14}
15

Valid use cases are:

1@Service()
2export class AdminOnly implements CanActivateResolver {
3    canActivate(
4        context: UserType,
5        payload,
6        descriptor: GenericGapiResolversType
7    ) {
8        return Observable.create(o => o.next(true));
9
10        return new Promise((r) => r(true));
11
12        return Observable.create(o => o.next(false));
13
14        return new Promise((r) => r(false));
15        if (context.type !== 'ADMIN') {
16            throw new Error('error');
17        }
18    }
19}
20

If you try to mix @Guard decorator and apply globaly guards it will merge them so you will have both of the guards.

@Interceptor - This abstraction can be used to modify or just log result before you process it to the client can be used like this:

Logging interceptor

1import { InterceptResolver, Service, GenericGapiResolversType } from '@gapi/core';
2import { Observable } from 'rxjs';
3import { tap } from 'rxjs/operators';
4import { UserType } from '../../user/types/user.type';
5
6@Service()
7export class LoggerInterceptor implements InterceptResolver {
8    intercept(
9        chainable$: Observable<any>,
10        context: UserType,
11        payload,
12        descriptor: GenericGapiResolversType
13    ) {
14        console.log('Before...');
15        const now = Date.now();
16        return chainable$.pipe(
17            tap(() => console.log(`After... ${Date.now() - now}ms`)),
18        );
19    }
20}

Then you can attach it inside Query, Mutation, Subscription decorators

1    @Interceptor(LoggerInterceptor)
2    @Query({
3        id: {
4            type: new GraphQLNonNull(GraphQLString)
5        }
6    })
7    findUser(root, { id }): Promise<User> {
8        return this.userService.findUserById(id);
9    }
10

You can also modify result returned

Modify interceptor

1import { InterceptResolver, Service, GenericGapiResolversType } from '@gapi/core';
2import { Observable } from 'rxjs';
3import { tap } from 'rxjs/operators';
4import { UserType } from '../../user/types/user.type';
5
6@Service()
7export class ModifyInterceptor implements InterceptResolver {
8    intercept(
9        chainable$: Observable<any>,
10        context: UserType,
11        payload,
12        descriptor: GenericGapiResolversType
13    ) {
14        console.log('Before...');
15        const now = Date.now();
16        return chainable$.pipe(
17            map((res) => {
18                console.log(`After... ${Date.now() - now}ms`);
19                return res;
20            }),
21        );
22    }
23}

@Module - This is the starting point of the application when we bootstrap our module inside root/src/main.ts.Also can be used to create another Modules which can be imported inside AppModule {imports: ...IMPORTS}

@Service - Passed above class, this Decorator will insert metadata related with this class and all Dependencies Injected inside constructor() so when application starts you will get a Singleton of many Services if they are not Factory Services(Will explain how to create Factory in next release).So you can use single instance of a Service injected everywhere inside your application.

@Inject - It will inject Service with specific NAME for example when using InjectionToken('my-name') you can do something like

1constructor(
2    @Inject('my-name') private name: string;
3) {}

@Injector - Use this very carefully! It will Inject Services before application is fully loaded used to load Instance of a class before the real load of application it is used only inside GapiObjectType because Types are the first thing that will be loaded inside Gapi Application so we need our Services on Processing Decorators which is when the application loads.If you can use Dependency Injection internally provided.

@InjectType - This is BETA decorator for now is used without Decorator sign @ example:

1@GapiObjectType()
2export class UserType {
3    readonly id: number | GraphQLScalarType = GraphQLInt;
4    readonly settings: string | UserSettings = InjectType(UserSettingsType);
5}

In future releases it will be used as follows:

1@GapiObjectType()
2export class UserType {
3    readonly id: number | GraphQLScalarType = GraphQLInt;
4    @InjectType(UserSettingsType) readonly settings: string;
5}

TODO: Better documentation...

Enjoy ! :)