feat: T-940 Create charges allong with plan create/update (#26)

app/graphql/mutations/plans/create.rb

@@ -10,7 +10,6 @@ class Create < BaseMutation
 
       argument :organization_id, String, required: true
       argument :name, String, required: true
-      argument :billable_metric_ids, [String]
       argument :code, String, required: true
       argument :frequency, Types::Plans::FrequencyEnum, required: true
       argument :billing_period, Types::Plans::BillingPeriodEnum, required: true
@@ -21,6 +20,8 @@ class Create < BaseMutation
       argument :trial_period, Float, required: false
       argument :description, String, required: false
 
+      argument :charges, [Types::Charges::Input]
+
       type Types::Plans::Object
 
       def resolve(**args)

app/graphql/mutations/plans/update.rb

@@ -9,7 +9,6 @@ class Update < BaseMutation
 
       argument :id, String, required: true
       argument :name, String, required: true
-      argument :billable_metric_ids, [String]
       argument :code, String, required: true
       argument :frequency, Types::Plans::FrequencyEnum, required: true
       argument :billing_period, Types::Plans::BillingPeriodEnum, required: true
@@ -20,6 +19,8 @@ class Update < BaseMutation
       argument :trial_period, Float, required: false
       argument :description, String, required: false
 
+      argument :charges, [Types::Charges::Input]
+
       type Types::Plans::Object
 
       def resolve(**args)

app/graphql/types/charges/frequency_enum.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Types
+  module Charges
+    class FrequencyEnum < Types::BaseEnum
+      graphql_name 'ChargeFrequency'
+
+      Charge::FREQUENCIES.each do |type|
+        value type
+      end
+    end
+  end
+end

app/graphql/types/charges/input.rb

@@ -0,0 +1,16 @@
+# frozen_string_literal: true
+
+module Types
+  module Charges
+    class Input < Types::BaseInputObject
+      graphql_name 'ChargeInput'
+
+      argument :billable_metric_id, ID, required: true
+      argument :amount_cents, Integer, required: true
+      argument :amount_currency, Types::CurrencyEnum, required: true
+      argument :frequency, Types::Charges::FrequencyEnum, required: true
+      argument :pro_rata, Boolean, required: true
+      argument :vat_rate, Float, required: false
+    end
+  end
+end

app/graphql/types/charges/object.rb

@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Types
+  module Charges
+    class Object < Types::BaseObject
+      graphql_name 'Charge'
+
+      field :id, ID, null: false
+      field :billable_metric, Types::BillableMetrics::Object, null: false
+      field :amount_cents, Integer, null: false
+      field :amount_currency, Types::CurrencyEnum, null: false
+      field :frequency, Types::Charges::FrequencyEnum, null: false
+      field :pro_rata, Boolean, null: false
+      field :vat_rate, Float
+
+      field :created_at, GraphQL::Types::ISO8601DateTime, null: false
+      field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
+    end
+  end
+end

app/graphql/types/plans/frequency_enum.rb

@@ -3,6 +3,8 @@
 module Types
   module Plans
     class FrequencyEnum < Types::BaseEnum
+      graphql_name 'PlanFrequency'
+
       Plan::FREQUENCIES.each do |type|
         value type
       end

app/graphql/types/plans/object.rb

@@ -19,7 +19,7 @@ class Object < Types::BaseObject
       field :trial_period, Float
       field :description, String
 
-      field :billable_metrics, [Types::BillableMetrics::Object]
+      field :charges, [Types::Charges::Object]
 
       field :created_at, GraphQL::Types::ISO8601DateTime, null: false
       field :updated_at, GraphQL::Types::ISO8601DateTime, null: false

app/models/charge.rb

@@ -3,4 +3,11 @@
 class Charge < ApplicationRecord
   belongs_to :plan
   belongs_to :billable_metric
+
+  FREQUENCIES = %i[
+    one_time
+    recurring
+  ].freeze
+
+  enum frequency: FREQUENCIES
 end

app/services/plans_service.rb

@@ -20,9 +20,8 @@ def create(**args)
       trial_period: args[:trial_period]
     )
 
-    # TODO: create charges
     # Validates billable metrics
-    metric_ids = args[:billable_metric_ids]
+    metric_ids = args[:charges].map { |c| c[:billable_metric_id] }.uniq
     if metric_ids.present? && plan.organization.billable_metrics.where(id: metric_ids).count != metric_ids.count
       return result.fail!('unprocessable_entity', 'Billable metrics does not exists')
     end
@@ -31,7 +30,8 @@ def create(**args)
       # TODO: better handling of validation errors
       plan.save!
 
-      plan.billable_metric_ids = metric_ids if metric_ids.present?
+      # TODO: group validation errors
+      args[:charges].each { |c| create_charge(plan, c) }
     end
 
     result.plan = plan
@@ -54,8 +54,7 @@ def update(**args)
     plan.vat_rate = args[:vat_rate]
     plan.trial_period = args[:trial_period]
 
-    # TODO: create charges
-    metric_ids = args[:billable_metric_ids]
+    metric_ids = args[:charges].map { |c| c[:billable_metric_id] }.uniq
     if metric_ids.present? && plan.organization.billable_metrics.where(id: metric_ids).count != metric_ids.count
       return result.fail!('unprocessable_entity', 'Billable metrics does not exists')
     end
@@ -64,7 +63,11 @@ def update(**args)
       # TODO: better handling of validation errors
       plan.save!
 
-      plan.billable_metric_ids = metric_ids if metric_ids.present?
+      # TODO: update existing instead of removing all
+      plan.charges.delete_all
+
+      # TODO: group validation errors
+      args[:charges].each { |c| create_charge(plan, c) }
     end
 
     result.plan = plan
@@ -81,4 +84,17 @@ def destroy(id)
     result.plan = plan
     result
   end
+
+  private
+
+  def create_charge(plan, args)
+    plan.charges.create!(
+      billable_metric_id: args[:billable_metric_id],
+      amount_cents: args[:amount_cents],
+      amount_currency: args[:amount_currency],
+      frequency: args[:frequency].to_sym,
+      pro_rata: args[:pro_rata],
+      vat_rate: args[:vat_rate]
+    )
+  end
 end

db/migrate/20220324141856_add_properties_to_charges.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class AddPropertiesToCharges < ActiveRecord::Migration[7.0]
+  def change
+    change_table :charges do |t|
+      t.integer :amount_cents, null: false
+      t.string :amount_currency, null: false
+      t.integer :frequency, null: false
+      t.boolean :pro_rata, null: false
+      t.float :vat_rate
+    end
+  end
+end

schema.graphql

@@ -27,6 +27,32 @@ enum BillingPeriodEnum {
   subscruption_date
 }
 
+type Charge {
+  amountCents: Int!
+  amountCurrency: CurrencyEnum!
+  billableMetric: BillableMetric!
+  createdAt: ISO8601DateTime!
+  frequency: ChargeFrequency!
+  id: ID!
+  proRata: Boolean!
+  updatedAt: ISO8601DateTime!
+  vatRate: Float
+}
+
+enum ChargeFrequency {
+  one_time
+  recurring
+}
+
+input ChargeInput {
+  amountCents: Int!
+  amountCurrency: CurrencyEnum!
+  billableMetricId: ID!
+  frequency: ChargeFrequency!
+  proRata: Boolean!
+  vatRate: Float
+}
+
 type CollectionMetadata {
   currentPage: Int!
   limitValue: Int!
@@ -56,16 +82,16 @@ Autogenerated input type of CreatePlan
 input CreatePlanInput {
   amountCents: Int!
   amountCurrency: CurrencyEnum!
-  billableMetricIds: [String!]!
   billingPeriod: BillingPeriodEnum!
+  charges: [ChargeInput!]!
 
   """
   A unique identifier for the client performing the mutation.
   """
   clientMutationId: String
   code: String!
   description: String
-  frequency: FrequencyEnum!
+  frequency: PlanFrequency!
   name: String!
   organizationId: String!
   proRata: Boolean!
@@ -129,12 +155,6 @@ type DestroyPlanPayload {
   id: ID
 }
 
-enum FrequencyEnum {
-  monthly
-  weekly
-  yearly
-}
-
 """
 An ISO 8601-encoded datetime
 """
@@ -232,12 +252,12 @@ type Organization {
 type Plan {
   amountCents: Int!
   amountCurrency: CurrencyEnum!
-  billableMetrics: [BillableMetric!]
   billingPeriod: BillingPeriodEnum!
+  charges: [Charge!]
   code: String!
   createdAt: ISO8601DateTime!
   description: String
-  frequency: FrequencyEnum!
+  frequency: PlanFrequency!
   id: ID!
   name: String!
   organization: Organization
@@ -252,6 +272,12 @@ type PlanCollection {
   metadata: CollectionMetadata!
 }
 
+enum PlanFrequency {
+  monthly
+  weekly
+  yearly
+}
+
 type Query {
   """
   Query billable metrics of an organization
@@ -307,16 +333,16 @@ Autogenerated input type of UpdatePlan
 input UpdatePlanInput {
   amountCents: Int!
   amountCurrency: CurrencyEnum!
-  billableMetricIds: [String!]!
   billingPeriod: BillingPeriodEnum!
+  charges: [ChargeInput!]!
 
   """
   A unique identifier for the client performing the mutation.
   """
   clientMutationId: String
   code: String!
   description: String
-  frequency: FrequencyEnum!
+  frequency: PlanFrequency!
   id: String!
   name: String!
   proRata: Boolean!