Service call and result of work

Services can only be called via .call and .call! methods.

Via .call!

The .call! method will fail if it catches any exception.

UsersService::Accept.call!(user: User.first)

Via .call

The .call method will only fail if it catches an exception in the input arguments. Internal and output attributes, as well as methods for failures — all this will be collected in the result.

UsersService::Accept.call(user: User.first)

Result

All services have the result of their work. For example, in case of success this call:

service_result = UsersService::Accept.call(user: User.first)

Will return this:

#<Servactory::Result:0x0000000107ad9e88 @user="...">

And then work with thе result in this way:

Notification::SendJob.perform_later(service_result.user.id)

Result content

Output attributes

Anything that has been added via the output method in the service will be available in Result.

Helpers

As a result of the work of the service, there are success? and failure? methods, which can help determine the result of the work for further processing.

Errors

It is possible to get all errors via the errors method, or just the first one via the error method.

Info

From outside the service, can get information about its input, internal, and output attributes.

It is valuable, when implementing complex class handling, for example.

For example, the following attributes are described in a service:

class BuildFullName < ApplicationService::Base
  input :first_name, type: String
  input :middle_name, type: String, required: false
  input :last_name, type: String

  internal :prepared_full_name, type: String

  output :full_name, type: String

  # ...
end

Get information about them in the following ways:

BuildFullName.info

# => <Servactory::Info::Result:0x00000001118c7078 @inputs=[:first_name, :middle_name, :last_name], @internals=[:prepared_full_name], @outputs=[:full_name]>

BuildFullName.info.inputs

# => [:first_name, :middle_name, :last_name]

BuildFullName.info.internals

# => [:prepared_full_name]

BuildFullName.info.outputs

# => [:full_name]