cmd-johnson/alosaur

Alosaur - Deno web framework with many decorators

Alosaur 🦖

Alosaur - Deno web framework 🦖.

• Area - these are the modules of your application.
• Controller - are responsible for controlling the flow of the application execution.
• Middleware - provide a convenient mechanism for filtering HTTP requests entering your application.
• Hooks - middleware for area, controller and actions with support DI. Have 3 life cyclic functions: onPreAction, onPostAction, onCatchAction
• Decorators - for query, cookie, parametrs, routes and etc.
• Dependency Injection - for all controllers and hooks by default from microsoft/TSyringe (more about alosaur injection).
• Render pages any template render engine More

Documentation

---

Features roadmap

Q4 2020 – Oct-Dec

• WebSocket example
• SSE
• OpenAPI type reference
• microservice connector with WASM
• implement passport strategy

---

Examples

• Basic + OpenAPI v3 generator (Swagger)
• CORS middleware
• SPA middleware
• Static content middleware
• Database PostgreSQL
• Template render: Dejs, Handlebars, Angular, Eta
• Body transform, validator
• DI
• Docker
• Hooks

Simple example

app.ts:

import { Controller, Get, Area, App } from 'https://deno.land/x/alosaur@v0.21.1/mod.ts';

@Controller() // or specific path @Controller("/home")
export class HomeController {
    @Get() // or specific path @Get("/hello")
    text() {
        return 'Hello world';
    }
}

// Declare module
@Area({
    controllers: [HomeController],
})
export class HomeArea {}

// Create alosaur application
const app = new App({
    areas: [HomeArea],
});

app.listen();

tsconfig.app.json:

{
    "compilerOptions": {
        "experimentalDecorators": true,
        "emitDecoratorMetadata": true
    }
}

And run

deno run --allow-net --allow-read --config ./tsconfig.app.json app.ts

---

TODO

• Add render views: Dejs and Handlebars

• Add return value JSON

• Add decorators:

• • @Area
• • @QueryParam
• • @Param param from url: /:id
• • @Body
• • @Cookie
• • @Req
• • @Res
• • @Middleware with regex route
• • @UseHook for contoller and actions
• • Support create custom decorators with app metadata

• Add middleware

• Add static middleware (example: app.useStatic)

• Add CORS middleware

• Add SPA middleware

• Add DI

• Add std exceptions

• Add CI with minimal tests.

• Add OpenAPI v3 generator (see /examples/basic/openapi.ts)

• Add OpenAPI type reference

• Add Hooks example

• Add WebSocket

• Add SSE

• Add validators example class-validator

• Add microservice connector with WASM

• Add benchmarks

• Transfer to Alosaur github organization

• Add docs and more examples

• Plugins & modules

• • Add Angular render engine
• • Add CLI with schematics (https://github.com/alosaur/alosaur-schematics)

• Examples

• • Add basic example
• • Add DI example
• • Add static serve example
• • Add Dejs view render example
• • Add example with SQL drivers (PostgreSQL)
• • Add basic example in Docker container
• • Add WebSocket example
• • Add example with WASM

OpenAPI v3

Full example

AlosaurOpenApiBuilder.create(settings)
  .addTitle("Basic Application")
  .addVersion("1.0.0")
  .addDescription("Example Alosaur OpenApi generate")
  .addServer({
    url: "http://localhost:8000",
    description: "Local server",
  })
  .saveToFile("./examples/basic/api.json");

Generate OpenAPI file:

deno run -A --config ./src/tsconfig.lib.json examples/basic/openapi.ts

Middleware

You can create middleware and register it in area or all application layer.

Full example

@Middleware(new RegExp('/'))
export class Log implements MiddlewareTarget<TState> {
    date: Date = new Date();

    onPreRequest(context: Context<TState>) {
        return new Promise((resolve, reject) => {
            this.date = new Date();
            resolve();
        });
    }

    onPostRequest(context: Context<TState>) {
        return new Promise((resolve, reject) => {
            console.log(new Date().getTime() - this.date.getTime());
            resolve();
        });
    }
}

Register in app settings

const settings: AppSettings = {
    areas: [HomeArea, InfoArea],
    middlewares: [Log],
};

or in app

const app = new App(settings);

app.use(/\//, new Log());

WebSocket middleware example

Use context.response.setNotRespond() for return the rest of the requests

Full example

export class WebsocketMiddleware implements PreRequestMiddleware {
  onPreRequest(context: Context) {
    const { conn, r: bufReader, w: bufWriter, headers } =
      context.request.serverRequest;

    acceptWebSocket({
      conn,
      bufReader,
      bufWriter,
      headers,
    })
      .then(ChatHandler) // execute chat
      .catch(async (e) => {
        console.error(`failed to accept websocket: ${e}`);
        await context.request.serverRequest.respond({ status: 400 });
      });

    context.response.setNotRespond(); // It is necessary to return the rest of the requests by standard
  }
}

Hooks

Hooks - middleware for area, controller and actions with supports DI container.

Hook in Alosaur there are three types: onPreAction, onPostAction, onCatchAction.

Full example

type PayloadType = string; // can use any type for payload
type State = any;

export class MyHook implements HookTarget<State, PayloadType> {

  // this hook run before controller action
  onPreAction(context: Context<State>, payload: PayloadType) {
      // you can rewrite result and set request immediately
      context.response.result = Content({error: {token: false}}, 403);
      context.response.setImmediately();
      // if response setted immediately no further action will be taken
  };
  
  // this hook run after controller action
  onPostAction(context: Context<State>, payload: PayloadType) {
    // you can filtered response result here
  };
  
  // this hook run only throw exception in controller action
  onCatchAction(context: Context<State>, payload: PayloadType) {
  
  };
}

uses:

@UseHook(MyContollerHook) // or @UseHook(MyHook, 'payload') for all actions in controller
@Controller()
export class HomeController {

    @UseHook(MyHook, 'payload') // only for one action
    @Get('/')
    text(@Res() res: any) {
        return ``;
    }
}

Global error handler

Errors that haven't been caught elsewhere get in here

const app = new App(
// app settings
);


// added global error handler
app.error((context: Context<any>, error: Error) => {
  context.response.result = Content("This page unprocessed error", (error as HttpError).httpCode || 500);
  context.response.setImmediately();
});

Action outputs: Content, View, Redirect

There are 3 ways of information output

• Content similar return {}; by default Status 200 OK
• View uses with template engine, return View("index", model);
• Redirect and RedirectPermanent status 301,302 return Redirect('/to/page')

Full example

return {}; // return 200 status

// or
return Content("Text or Model", 404); // return 404 status

// or 
return View("page", 404); // return 404 status

Render pages

Alosaur can suppport any html renderer. All you have to do is define the rendering function in the settings. For example Dejs, Handlebars, Angular, Eta

// Handlebars
...
// Basedir path
const viewPath = `${Deno.cwd()}/examples/handlebars/views`;

// Create Handlebars render
const handle = new Handlebars();

app.useViewRender({
    type: 'handlebars',
    basePath: viewPath,
    getBody: async (path: string, model: any, config: ViewRenderConfig) => await handle.renderView(path, model),
});

...

Handlebars support custom config, more about handlebars for deno

 new Handlebars(
    {
        baseDir: viewPath,
        extname: '.hbs',
        layoutsDir: 'layouts/',
        partialsDir: 'partials/',
        defaultLayout: 'main',
        helpers: undefined,
        compilerOptions: undefined,
    }
)

Transformers and validators

You can use different transformers

For example class-validator and class-transformer for body.

Full example

post.model.ts:

import validator from "https://jspm.dev/class-validator@0.8.5";

const { Length, Contains, IsInt, Min, Max, IsEmail, IsFQDN, IsDate } =
  validator;

export class PostModel {
  @Length(10, 20)
  title?: string;

  @Contains("hello")
  text?: string;

  @IsInt()
  @Min(0)
  @Max(10)
  rating?: number;

  @IsEmail()
  email?: string;
}

app.ts

import validator from "https://jspm.dev/class-validator@0.8.5";
import transformer from "https://jspm.dev/class-transformer@0.2.3";
import { App, Area, Controller, Post, Body } from 'https://deno.land/x/alosaur/mod.ts';
import { PostModel } from './post.model.ts';

const { validate } = validator;
const { plainToClass } = transformer;

// Create controller
@Controller()
export class HomeController {

    @Post('/')
    async post(@Body(PostModel) data: PostModel) {

        return {
            data,
            errors: await validate(data)
        }
    }
}

// Declare controller in area
@Area({
    controllers: [HomeController],
})
export class HomeArea { }

// Create app
const app = new App({
    areas: [HomeArea],
});

// add transform function
app.useTransform({
    type: 'body', // parse body params
    getTransform: (transform: any, body: any) => {
        return plainToClass(transform, body);
    }
})

// serve application
app.listen();

You can also use just a function instead of a transformer.

function parser(body): ParsedObject {
    // your code
    return body;
}

...
@Post('/')
post(@Body(parser) data: ParsedObject) {

}

Custom Decorators

You can add any decorator and put it in a DI system.

Full example

Example with hooks:

import {
    Content,
    Context,
    HookTarget,
    BusinessType,
    getMetadataArgsStorage,
    container
} from "https://deno.land/x/alosaur/mod.ts";

type AuthorizeRoleType = string | undefined;

/**
 * Authorize decorator with role
 */
export function Authorize(role?: AuthorizeRoleType): Function {
  return function (object: any, methodName?: string) {
    // add hook to global metadata
    getMetadataArgsStorage().hooks.push({
      type: methodName ? BusinessType.Action : BusinessType.Controller,
      object,
      target: object.constructor,
      method: methodName,
      instance: container.resolve(AutorizeHook),
      payload: role,
    });
  };
}

export class AutorizeHook implements HookTarget<unknown, AuthorizeRoleType> {
  onPreAction(context: Context<unknown>, role: AuthorizeRoleType) {
    const queryParams = getQueryParams(context.request.url);

    if (queryParams == undefined || queryParams.get("role") !== role) {
      context.response.result = Content({ error: { token: false } }, 403);
      context.response.setImmediately();
    }
  }
}

Then you can add anywhere you want. For example action of controller:

  // ..controller

  // action
  @Authorize("admin")
  @Get("/protected")
  getAdminPage() {
    return "Hi! this protected info";
  }