Setup the project

Install the nestjs cli npm i -g @nestjs/cli.
Check the version installed of nestjs nest --version.
You have the documentation for help nest --help.
Recomended plugings to development prettier, eslint, editor config.
Validator of shapes npm i class-validator class-transformer
Utility types in nestjs npm i @nestjs/mapped-types.

Handling the packages with npm

To install a specific version of a package npm install package@version.
To uninstall a global package npm uninstall -g package.

Commands for Nestjs-cli

To initialize a new project nest new project.
To create a controller nest g co controllerName the extra flag --flat creates the controller with not a folder specific for the controller the name is tuned to show that is a controllers like product.controllers.js
To create a service nest g s path.
To create a pipe nest g pipe path.
To create a module nest g mo name.

About using NestJS

When we are definig routes in nestjs doesn't matter if the route that i specify has a starting slash or final slash all the routes omit the starting and the trailing slash for example /tools/ is the same as tools.
In routes when i define a dinamic route like /products/:id and after i define a static route that overlaps with the id like /products/filter the second route can not be interpreted beause the part filter is interpreted as the argument id in the first route to avoid that the static routes must be defined at first and the last must be the dinamically routes.
When a controller is created with the cli it creates two files one for the logic inside the controller and the other for unit tests, the second file has naming pattern like .spec.js, using the cli is a best option beacuse it connects the controllers in the main module.
Also when a controller is created with the cli tool the new controller file has a definition for the enpoint so i can avoid to write the name of the global enpoint all around the code.
Using the specific object Res and Req from nestjs with Request, Response from express we have the advantage that we see the data in the original express object, also we can response with that object and use all the builtin features.
The injection of dependency of services is made into the controllers code, adding first of all the service then when have to declarate the service into the constructor with the shorthad and nest will understand that as a inyection dependenci.
If i am using the object of express to manage the response we cannot use the return inside the controller to return the response that is the way that nest do it, so i have also manually to return that response.
The exceptions into @nestjs/commons made the response for the api with status codes a way easy that can be implemented into services, for example to handle when a search into a database has no response and want to response with the status code 404, there are another kinds of exeptions.
The pipes that are another common in nestjs allows to transform and validate data received before enter into the controller, this are required normally to validate when the data comes from params, query becuase its data is received as string and must be transformed, the builtint pipes must be placed inside the http decorators, also the pipes can be customized.
The customized pipes can be used as any other built int pipes.

The documentation of nest specify that we should use classes instead of interfaces to validate the shape and types in execution time and also in development time, and setup the code with:

  // main.ts
  import { ValidationPipe } from '@nestjs/common';
  ...
  app.useGlobalPipes(
    new ValidationPipe({
      whitelist: true, // Discard unexpected types for body
      forbidNonWhitelisted: true, // Alert for unexpected types for body
      disableErrorMessages: true, // Doesn't show error messages in production
    })
  );
  ...

When the code is moved from the basic structure of controllers and services to a module we have to remove the contollers and providers inyection into the main module, also we have to inyect that dependencies inside each module, also i have to import into the main module the other modules.
When we are sharing services between modules first we have to export the service in the parent module, where we will require that service we have to import the module parent inside the worker module, and inside the service that works generally we have to import normally the service following the full path for the file.
When we are talking about dependency injection with the pattern singleton we can use the provider parameter into the module, there are some kind of injection useClass that is the normal dependency injection, there is other useValue that is an injection of a value with singleton, the other injection is useFactory the features is that asynchronous and allows the dependency injection.
With the previous knowledge we have to use other code of nestjs like Global a decorator that can be usefull to share values globally combined with the dependency injection, and then export that useValue and the value can be used globally with only using the Inject decorator inside the constructor of the service or the controller.
To make calls to another apis inside nestjs we have to use a module called HttpModule and a service from that module called HttpService that comes from the module @nestjs/axios that is a un implementation of axios.
To work with env variables we can use another module of nestjs @nestjs/config that allows to config the env files and work with them of the right way, The config module must be configured in the appmodule, and the config service is the one that can be used to get the values of the enviroment variables with help the method get.
With the statement export default when i have to import i dont have to make destructuring only the importation like import config from './config'.
To validate the schema of the configuration we can use the module joi to valida from the configuration in the app.module the config schema.
The documentation is easy of implement with this steps:
1. import the module @nestjs/swagger.
2. add the configuration into the main.ts before launch the server into a port, this alredy start the documentation.
3. Into the models i have to change the @nestjs/mapped-types by @nestjs/swagger to interpret the data automatically.
4. Into the nestjs-cli.json configure the compilerOptions: {} adding the pluggins to the new module.
5. Then we can use the api decorators inside controllers, models, some of them are ApiOperation, ApiProperty...

Commands for docker

docker-compose up -d servicename to launch the service of the docker compose
docker-compose ps to list all the services
docker-compose down to strip down the service
docker-compose logs -f servicename to show the log register for the service
docker-compose exec servicename bash to launch a console for the service
docker ps to show the whole services on the system
docker inspect to show more information about the system
docker run --name name -p porthost:portcontainer image this will create the docker image.
docker run --name name -e environmentvar -p portHost:portContainer image this will create an image.
docker stop containername to stop the container.
docker ps --all to list all the containers.

d3w3r/nestjs

Setup the project

Handling the packages with npm

Commands for Nestjs-cli

About using NestJS

Commands for docker

Commands for postgres

Git commands

TODO LIST