Configuration overhaul: make mail-related configuration clearer

[josecelano]

Parent issue: #591

Make mail-related configuration more straightforward. There are a couple of options that could be confusing: email_on_signup and email_verification_enabled.

Current version

[auth]
email_on_signup = "optional"

[mail]
email_verification_enabled = false
from = "example@email.com"
reply_to = "noreply@email.com"

New version

[registration]
# Other future options related to registration in addition to mail.
# All options related to mail go into the mail subtype.

[registration.mail]
required = true
verified = true

The new version adds a new section for the registration configuration. That section contains a subtype with two fields for the email:

• required: true if the email is mandatory for registration.
• verified: true if the app sends a verification email to verify the user's email.

The second one maps directly to the old field email_verification_enabled.

Regarding the first one email_on_signup, it has these values:

• required: the user must provide a valid email even if email verification is disabled.
• optional: the app shows the email field in the registration form, but the user can omit it. It can be empty. Some user's profiles may have it and others may not.
• ignored: the frontend app does not show the email field at all. However, the API accepts that param in the POST request but, it ignores it.

It will be simplified:

• When required is true the signup form contains the email field and is mandatory.
• When required is false the signup form does NOT contain the email field and is not mandatory. However in the future, the user can provide an email in the user's profile settings page.

Notes

We have to check some invalid configurations and show an error when the application is starting.

• If registration.mail.verified is true, the mail server configuration must be provided (it can't be None).

[josecelano]

Hey @da2ce7, can you please review this? If we implement it as I have described it, we will remove the option to provide an email, even if it's not mandatory, until we allow it in the profile settings (new feature).

This could be a helpful feature for some reason. I think email is the only way to communicate with users now, so even if we don't require it, it could be useful to allow the user to provide it.

[da2ce7]

@josecelano

I would rename mail to email.

Here are the different variants.

Registration Disabled:

# [registration]

Registration without email option:

[registration]

Registration optionally including an email address:

[registration]
[registration.email]

Registration with email:

[registration]
[registration.email]
required = true

Registration with optional email, but if email is supplied it is verified:

[registration]
[registration.email]
verified = true

Registration with email and email is verified:

[registration]
[registration.email]
required = true
verified = true

[josecelano]

Hi @da2ce7, just to confirm, do you prefer to represent the omitted value for required and verified with an Option or set the default value to false?

This would be the Rust struct using Options (omitting other configuration fields):

struct Config {
  registration: Option<Registration> // default None. Registration disabled.
}

struct Registration {
  mail: Option<Email> // default None. Registration without email.
}

struct Email {
  required: Option<bool>, // default None.
  verified: Option<bool>, // default None.
}

And this would be the Rust struct using defaults (omitting other configuration fields):

struct Config {
  registration: Option<Registration> // default None. Registration disabled.
}

struct Registration {
  mail: Option<Email> // default None. Registration without email.
}

struct Email {
  required: bool, // default false
  verified: bool, // default false
}

In practice, you must assume a true or false default value for Option. So I would use the direct option.

And these are the "debug" instances for each case (assuming no optional booleans):

Registration Disabled:

Config {
  registration: None
}

Registration without email option:

Config {
  registration: Some(Registration {
    mail: None
  })
}

Registration optionally including an email address:

Config {
  registration: Some(Registration {
    mail: Some({
      required: false,
      verified: false,
    })
  })
}

Registration with email:

Config {
  registration: Some(Registration {
    mail: Some({
      required: true,
      verified: false,
    })
  })
}

Registration with optional email, but if email is supplied it is verified:

Config {
  registration: Some(Registration {
    mail: Some({
      required: false,
      verified: true,
    })
  })
}

Registration with email and email is verified:

Config {
  registration: Some(Registration {
    mail: Some({
      required: true,
      verified: true,
    })
  })
}

And in JSON:

Registration Disabled:

{}

Registration without email option:

{
  "registration": {}
}

Registration optionally including an email address:

{
  "registration": {
    "email": {}
  }
}

Registration with email:

{
  "registration": {
    "email": {
      "required": true
    }
  }
}

Registration with optional email, but if email is supplied it is verified:

{
  "registration": {
    "email": {
      "verified": true
    }
  }
}

Registration with email and email is verified:

{
  "registration": {
    "email": {
      "required": true,
      "verified": true
    }
  }
}