how we can add login method in usercontroller class in loopback4 API? needs more clarification on this

[kanusoni]

Hello,
I have created User controller in loopback4 Explorer but i need login method for JWT authentication.
Whatever is written in loopback.io tutorial is bit confusing so do you have any other tutorial for the clarification.

[dougal83]

Please find a working example below:

  @post('/users/login', {
    responses: {
      '200': {
        description: 'Token',
        content: {
          'application/json': {
            schema: {
              type: 'object',
              properties: {
                token: {
                  type: 'string',
                },
              },
            },
          },
        },
      },
    },
  })
  async login(
    @requestBody(CredentialsRequestBody) credentials: Credentials,
  ): Promise<{token: string}> {
    // ensure the user exists, and the password is correct
    const user = await this.userService.verifyCredentials(credentials);


    // convert a User object into a UserProfile object (reduced set of properties)
    const userProfile = this.userService.convertToUserProfile(user);


    // create a JSON Web Token based on the user profile
    const token = await this.jwtService.generateToken(userProfile);


    return {token};
  }
}

From example shopping. Hope that helps. Please explain what is confusing and we'll see what can be done to improve docs.

[kanusoni]

yes, i have tried this...but i am getting errors.
The variables that you are using like (Credentials, userservice, jwtservice) where we need to define this in our application

Error is like:-
Parameter 'credentials' of public method from exported class has or is using private name 'Credentials'.

Property 'userService' does not exist on type 'UserController'.

[dougal83]

@kanusoni Please take a closer look at the Shopping example and follow the breadcrumbs (look at Constructor that instantiates services and follow the imports to find their implementation. It takes time to familiarise yourself but it is worth it if the tutorial does not suit you.

[dhmlau]

@kanusoni, we recently published an extension called @loopback/authentication-jwt, this might make adding jwt authentication eaiser: https://github.com/strongloop/loopback-next/tree/master/extensions/authentication-jwt.

While learning how to use this extension, I created this blog: https://medium.com/@MobileDiana/add-jwt-authentication-in-your-loopback-4-application-325137642c2c. Hope this helps.

[kanusoni]

@dhmlau Thanks Diana for you reply.
The blog which has been mentioned in above comment section is really helpful. now i am able to create both login and signup method in usercontroller class.
Thanks Again for publishing this blog.

[kanusoni]

@dhmlau can you help me out in the below issue:-
while i am signing in loopback4 explorer with credentials email: foo@bar.com and password: foobar
i am getting error which is shown in screenshot.

because of this issue JWT token is also not generating.
your help will be appreciated. Thanks.

[deepakrkris]

@kanusoni please provide a sample project or sandbox to check your code

[dhmlau]

@kanusoni please provide a sample project or sandbox to check your code

+1. From the error in the screen shot, it seems like the password was not specified. If it was specified and still got this error, it's the best if you can share your app. Thanks.

[kanusoni]

newlbapp.zip <https://drive.google.com/file/d/1ydc8jzw3VRHhaQ_PGn1drz5FJZ3_qsaB/view?usp=drive_web>

…

On Fri, May 15, 2020 at 5:28 AM Diana Lau ***@***.***> wrote: @kanusoni <https://github.com/kanusoni> please provide a sample project or sandbox to check your code +1. From the error in the screen shot, it seems like the password was not specified. If it was specified and still got this error, it's the best if you can share your app. Thanks. — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#5407 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/APSACQH3LNNDATC3TP6QOLDRRSASDANCNFSM4M7OK7VQ> .

[kanusoni]

@deepakrkris @dhmlau sent App to you. please check the code and let me know the solution.
Thanks.