deno_nest

Rely on oak@v12.6.1 and hono@v3.8.1 to simulate some annotation functions of NestJS which is a great frame for Node.js.

I will update the oak or Hono version if need.

The previous framework name was oak_nest, now renamed deno_nest.

It is recommended to use Hono as the underlying layer because its performance is better.

start

You can use CLI to init:

deno run --allow-env --allow-run --allow-net --allow-read --allow-write --import-map https://deno.land/x/deno_nest@v3.1.7/cli/import_map.json https://deno.land/x/deno_nest@v3.1.7/cli/main.ts

Or you can install CLI by:

deno install --allow-env --allow-run --allow-net --allow-read --allow-write --import-map https://deno.land/x/deno_nest@v3.1.7/cli/import_map.json  -n nest -f https://deno.land/x/deno_nest@v3.1.7/cli/main.ts

Then use as nest or nest new.

config

If you not use CLI create project, then efore start your app, you may set deno.json or deno.jsonc before:

"compilerOptions": {
  "emitDecoratorMetadata": true,
  "strictPropertyInitialization": false
},
"imports": {
  "@nest": "https://deno.land/x/deno_nest@v3.1.7/mod.ts",
  "@nest/hono": "https://deno.land/x/deno_nest@v3.1.7/modules/hono/mod.ts",
  "@nest/oak": "https://deno.land/x/deno_nest@v3.1.7/modules/oak/mod.ts",
  "class_validator": "https://deno.land/x/deno_class_validator@v1.0.0/mod.ts"
}

The @nest/hono and @nest/oak only need one.

run

You can see the current App by:

deno task dev

Demo

Controller

Decorators Module、Controller、Injectable、UseGuards、Get、Post、Body、Headers、Query、Res、Req now are available：

import {
  Body,
  type CanActivate,
  Context,
  Controller,
  createParamDecorator,
  createParamDecoratorWithLowLevel,
  ForbiddenException,
  Get,
  Headers,
  Post,
  Query,
  Res,
  UseGuards,
} from "@nest";
import mockjs from "https://deno.land/x/deno_mock@v2.0.0/mod.ts";
import { delay } from "https://deno.land/std@0.194.0/async/mod.ts";

class AuthGuard implements CanActivate {
  async canActivate(context: Context): Promise<boolean> {
    console.log("--AuthGuard---");
    await delay(100);
    // throw new ForbiddenException('this is AuthGuard error');
    return true;
  }
}

class AuthGuard2 implements CanActivate {
  async canActivate(context: Context): Promise<boolean> {
    console.log("--AuthGuard2---");
    return true;
  }
}

class AuthGuard3 implements CanActivate {
  async canActivate(context: Context): Promise<boolean> {
    throw new ForbiddenException("this is AuthGuard3 error");
    return false;
  }
}

@UseGuards(AuthGuard)
@Controller("/user")
export class UserController {
  @UseGuards(AuthGuard2, AuthGuard3)
  @Get("/info/:id")
  test(
    @add() name: string,
    @Query() params: any,
    @Query("age") age: string,
  ) {
    console.log(params, age);
    return "role info " + name + " - " +
      JSON.stringify(params);
  }

  @Get("/info")
  getInfo(@Res() res: Response, @Query() params: any) {
    console.log(params);
    res.body = "role get info " + JSON.stringify(params);
  }

  @Get("list")
  list(context: Context) {
    console.log("---list----");
    this.testInnerCall();
    context.response.body = "list";
  }

  testInnerCall() {
    console.log("---test---");
  }
}

You can customize the decorator by createParamDecorator or createParamDecoratorWithLowLevel:

const Add = createParamDecorator(async (ctx: any) => {
  const result = ctx.request.body(); // content type automatically detected
  if (result.type === "json") {
    const value = await result.value; // an object of parsed JSON
    // console.log('value', value);
    return value.userId;
  }
});

function Add2(params: any) {
  return createParamDecoratorWithLowLevel(async (ctx: any) => {
    return params;
  });
}

Then use like this:

@Post("/info")
info(
  @Add() name: string,
  @Add2("name") name2: string,
  @Body() params: any,
  @Headers() headers: any,
  @Headers("host") host: any,
  @Res() res: Response,
) {
  console.log("ctx", name, name2, params, headers, host);
  res.body = "role info " + name + name2;
}

You can also use class validator like this:

class Dto {
  @Max(2)
  @Min(1)
  pageNum!: number;

  @Max(5)
  @Min(1)
  pageCount!: number;
}

@Post("/info")
info(
  @Body() params: Dto
) {
  console.log("ctx", params);
  return "role info " + name;
}

The Body decorator is using deno_class_validator for validator, which is forked from class-validator which is using in Node.js, if it fails, then will throw an 400 Error.

Controller use Service

You can use Injectable to flag the service can be injectable, and it can be used by your Controller or other Service.

import { Injectable } from "@nest";

@Injectable()
export class RoleService {
  info() {
    return "info from RoleService";
  }
}

@Injectable()
export class UserService {
  constructor(
    private readonly roleService: RoleService,
  ) {}
  info() {
    return mockjs.mock({
      name: "@name",
      "age|1-100": 50,
      "val|0-2": 1,
      role: this.roleService.info(),
      user2: this.userService2.info(),
    });
  }
}

@Controller("user")
export class User2Controller {
  constructor(
    private readonly userService: UserService,
    private readonly roleService: RoleService,
  ) {
  }
  @Get("/user2")
  info() {
    return this.userService.info() + this.roleService.info();
  }
}

If you like to use the Service alone in anywhere, you can with Factory like this:

import { Factory } from "@nest";
Factory(UserService).info();

use Module

First is the AppModule:

import { Module } from "@nest";
import { AppController } from "./app.controller.ts";
import { UserModule } from "./user/user.module.ts";

@Module({
  imports: [
    UserModule,
  ],
  controllers: [AppController],
})
export class AppModule {}

Then is UserModule, and the providers can contain the services which are not used by controllers.

import { Module } from "@nest";
import { RoleController } from "./controllers/role.controller.ts";
import { UserController } from "./controllers/user.controller.ts";
import { User2Controller } from "./controllers/user2.controller.ts";
import { ScheduleService } from "./services/schedule.service.ts";

@Module({
  imports: [],
  controllers: [
    UserController,
    RoleController,
    User2Controller,
  ],
  providers: [
    ScheduleService,
  ],
})
export class UserModule {
}

Then this is your main.ts:

import { Context, isHttpError, NestFactory, Status } from "@nest";
import { HonoRouter } from "@nest/hono";
import { AppModule } from "./app.module.ts";

const app = await NestFactory.create(AppModule, HonoRouter);
app.setGlobalPrefix("api");

// Timing
app.use(async (req, res, next) => {
  const start = Date.now();
  await next();
  const ms = Date.now() - start;
  res.headers.set("X-Response-Time", `${ms}ms`);
});

app.get("/", (_req, res) => {
  res.body = "Hello World!";
});

const port = Number(Deno.env.get("PORT") || 1000);
console.log(`app will start with: http://localhost:${port}`);
await app.listen({ port });

If you want to use oak instead of Hono, you can change like this:

import { OakRouter } from "@nest/oak";

const app = await NestFactory.create(AppModule, OakRouter);

use static files

If you want to serve your own static files, you can use the following:

app.useStaticAssets("example/static", {
  prefix: "static",
});

It must be used before the routes (app.use(app.routes())).

connect db

If you want to connect db such as Mongodb, you can do like this:

import { Module } from "@nest";
import { AppController } from "./app.controller.ts";
import { UserModule } from "./user/user.module.ts";

@Module({
  imports: [
    MongoFactory.forRoot(globals.db), // it can return a Promise
    UserModule,
  ],
  controllers: [AppController],
})
export class AppModule {}

And you may provide a method to inject your Model:

export const InjectModel = (Cls: Constructor) =>
(
  target: Constructor,
  _property: any,
  index: number,
) => {
  Reflect.defineMetadata("design:inject" + index, {
    params: [Cls],
    fn: getModel,
  }, target);
};

The function getModel can return a new Model which will be used in Service. It maybe like this:

async function getModel<T>(
  cls: SchemaCls,
): Promise<Model<T>> {
  // do some else
  return new cls();
}

You can also use the Inject decorator to help you:

import { Inject } from "@nest";
export const InjectModel = (Cls: Constructor) => Inject(() => getModel(Cls));

To support it, I changed the router.register method to asynchronous. It was not a pleasant decision.

Here is a Service example:

@Injectable()
export class UserService {
  constructor(@InjectModel(User) private readonly model: Model<User>) {
  }
  async save(createUserDto: AddUserDto): Promise<string> {
    console.log(this.model);
    const id = await this.model.insertOne(createUserDto);
    console.log(id);
    return id.toString();
  }
}

In the above code, this.model is the getModel result.

register Dynamic Module

You can also register a Dynamic Module like this:

import { DynamicModule } from "@nest";
import { ASYNC_KEY } from "./async.constant.ts";
import { AsyncService } from "./async.service.ts";

export class AsyncModule {
  static register(db: string): DynamicModule {
    return {
      module: AsyncModule,
      providers: [{
        provide: ASYNC_KEY,
        useFactory: () => { // can be async
          console.log("AsyncModule.register: ", db);
          return Promise.resolve(true);
        },
      }, AsyncService],
    };
  }
}

And the AsyncService like this:

import { Inject, Injectable } from "@nest";
import { ASYNC_KEY } from "./async.constant.ts";

@Injectable()
export class AsyncService {
  constructor(@Inject(ASYNC_KEY) private readonly connection: string) {
    console.log(
      "injected CONNECTION_ASYNC maybe true: ",
      this.connection,
      "----",
      connection,
    );
  }

  info() {
    return "info from AsyncService and the conecction is: " + this.connection;
  }
}

The ASYNC_KEY recommended use symbol like this:

export const ASYNC_KEY = Symbol("CONNECTION_ASYNC");

Then the AsyncModule can be use by other modules and the service can be injected to other service.

@Module({
  imports: [
    UserModule,
    AsyncModule.register("localhost:4878"),
  ],
  controllers: [AppController],
})
export class AppModule {}

You can also see the RedisModule example this way or use the modules such as cache and scheduler in the modules dir.

use alias

If you want to manage your API with version, then you can use the alias.

Controller alias

no prefix

Here is a controller file named user.controller.ts:

@Controller("user", {
  alias: "/v1/user/",
})
export class UserController {
  @Get("/info")
  info() {
    return "info";
  }
}

Then you will have both API such as /user/info and /v1/user/info.

has global prefix

If you has setted global API prefix by this:

const app = await NestFactory.create(AppModule);
app.setGlobalPrefix("/api");

Then you API is /api/user/info and /v1/user/info.

If you want your alias with prefix such as /api/v1/user/info, you can set alias with template ${prefix}/:

@Controller("user", {
  alias: "${prefix}/v1/user/",
})

Similarly, you can set suffix like this:

@Controller("user", {
  alias: "/v1/${suffix}",
})

Of course, you can set it at the same time:

@Controller("user", {
  alias: "${prefix}/v1/${suffix}",
})

If you want your API not start with global prefix,then use the options isAbsolute:

@Controller("/v1/user", {
  isAbsolute: true,
})

method alias

@Controller("/user")
export class UserController {
  @Get("/info", {
    alias: "/v1/user/info",
  })
  info() {}
}

Then you will have both API /user/info and /v1/user/info.

template

The template ${prefix} and ${suffix} also work like above, and add ${controller}:

@Controller("/user")
export class UserController {
  @Get("/info", {
    alias: "${prefix}/v3/${controller}/${suffix}",
  })
  info() {}
}

isAbsolute

isAbsolute also work to set a Special API such as:

@Controller("/user")
export class UserController {
  @Get("/v2/user/info", {
    isAbsolute: true,
  })
  info() {}
}

Then get an API /v2/user/info.

You can also use template as same:

@Controller("/user")
export class UserController {
  @Get("${prefix}/v2/${controller}/info", {
    isAbsolute: true,
  })
  info() {}
}

But if you set global prefix /api, this will get /api/v2/user/info.

global prefix exclude

If you not want to set isAbsolute in every Controller, you can set an RegExp by exclude when you setGlobalPrefix, it can be a String which will call new RegExp or RegExp.

const app = await NestFactory.create(AppModule);
app.setGlobalPrefix("/api", {
  exclude: ["^/?v\\d{1,3}/", /^\/?v\d{1,3}\//],
});

unit

If you want to test your application, you can use createTestingModule to help use.

First, let us create Service B and C, create a Controller A.

@Injectable()
class B {
  findAll() {
    return "b";
  }
}

@Controller("")
class A {
  constructor(private readonly b: B) {}

  find() {
    return this.b.findAll();
  }
}

Then use createTestingModule:

import { createTestingModule } from "@nest";

Deno.test("test origin only with controller", async () => {
  const moduleRef = await createTestingModule({
    controllers: [A],
  })
    .compile();
  const a = await moduleRef.get(A);
  assert(a instanceof A);
  const b = await moduleRef.get(B);
  assert(b instanceof B);
  assert(a["b"] === b);
  assertEquals(a.find(), "b");
});

Deno.test("test origin with providers", async () => {
  const moduleRef = await createTestingModule({
    controllers: [A],
    providers: [B],
  })
    .compile();
  const a = await moduleRef.get(A);
  assert(a instanceof A);
  const b = await moduleRef.get(B);
  assert(b instanceof B);
  assert(a["b"] === b);
  assertEquals(a.find(), "b");
});

Deno.test("inject data by other object", async () => {
  const d = {
    findAll() {
      return "d";
    },
  };
  const moduleRef = await createTestingModule({
    controllers: [A],
  }).overrideProvider(B, d)
    .compile();
  const a = await moduleRef.get(A);
  assert(a instanceof A);
  const b = await moduleRef.get(B);
  assert(!(b instanceof B));
  assert(a["b"] === b);
  assert(b === d);
  assertEquals(a.find(), "d");
});

Deno.test("change provider self", async () => {
  const moduleRef = await createTestingModule({
    controllers: [A],
  })
    .compile();
  const a = await moduleRef.get(A);
  assert(a instanceof A);
  const b = await moduleRef.get(B);
  assert(b instanceof B);

  b.findAll = () => {
    return "bb";
  };

  assert(a["b"] === b);
  assertEquals(a.find(), "bb");
});

Deno.test("resolve will return not same", async () => {
  const moduleRef = await createTestingModule({
    controllers: [A],
  })
    .compile();
  const b = await moduleRef.get(B);
  assert(b instanceof B);
  const c = await moduleRef.resolve(B);
  assert(c instanceof B);
  assert(b !== c);

  const d = await moduleRef.resolve(B);
  assert(d !== c);
});

TODO

support Guard
support Interceptor
support ExceptionFilter
unit test self
provide API to help unit
support oak
support hono
static assets
support lifecycle
Nest CLI
Nest Doc
unit Hono and Oak self

You can see more in the example dirs.