Merge pull request #15 from exstake/feature/create-exchange-order-mutations

Feature/create exchange order mutations

app/graphql/inputs/create_buy_crypto_order_attributes_input.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+module Inputs
+  class CreateBuyCryptoOrderAttributesInput < Types::BaseInputObject
+    argument :currency_id, ID, required: true
+    argument :amount_cents, Integer, "Amount to be paid", required: true
+  end
+end

app/graphql/inputs/create_sell_crypto_order_attributes_input.rb

@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+module Inputs
+  class CreateSellCryptoOrderAttributesInput < Types::BaseInputObject
+    argument :currency_id, ID, required: true
+    argument :amount, String, "Amount to be paid", required: true
+  end
+end

app/graphql/mutations/base_mutation.rb

@@ -6,8 +6,16 @@ module Mutations
     input_object_class Types::BaseInputObject
     object_class Types::BaseObject
 
-    field :errors, [String],
+    field :errors, [Types::RecordInvalidType],
       null: true,
       description: "Errors encountered during execution of the mutation."
+
+    def current_user
+      context[:current_user]
+    end
+
+    def decode_id(encoded_id)
+      GraphQL::Schema::UniqueWithinType.decode(encoded_id).last
+    end
   end
 end

app/graphql/mutations/create_buy_crypto_order.rb

@@ -0,0 +1,26 @@
+# frozen_string_literal: true
+module Mutations
+  class CreateBuyCryptoOrder < BaseMutation
+    field :order, Types::BuyCryptoOrderType, null: true
+
+    argument :order, Inputs::CreateBuyCryptoOrderAttributesInput, required: true
+
+    def resolve(order:)
+      currency_id = decode_id(order[:currency_id])
+
+      ActiveRecord::Base.transaction do
+        current_user.fiat_balance.withdrawal!(order[:amount_cents])
+
+        record = BuyCryptoOrder.create!(
+          paid_amount_cents: order[:amount_cents],
+          currency_id: currency_id,
+          user_id: current_user.id,
+        )
+
+        { order: record }
+      rescue ActiveRecord::RecordInvalid => e
+        { errors: Resolvers::ModelErrors.from_active_record_model(e.record) }
+      end
+    end
+  end
+end

app/graphql/mutations/create_sell_crypto_order.rb

@@ -0,0 +1,28 @@
+# frozen_string_literal: true
+module Mutations
+  class CreateSellCryptoOrder < BaseMutation
+    field :order, Types::SellCryptoOrderType, null: true
+
+    argument :order, Inputs::CreateSellCryptoOrderAttributesInput, required: true
+
+    def resolve(order:)
+      currency_id = decode_id(order[:currency_id])
+      amount = BigDecimal(order[:amount])
+
+      ActiveRecord::Base.transaction do
+        current_user.balances.find_by!(currency_id: currency_id)
+          .withdrawal!(amount)
+
+        record = SellCryptoOrder.create(
+          paid_amount: amount,
+          currency_id: currency_id,
+          user_id: current_user.id,
+        )
+
+        { order: record }
+      rescue ActiveRecord::RecordInvalid => e
+        { errors: Resolvers::ModelErrors.from_active_record_model(e.record) }
+      end
+    end
+  end
+end

app/graphql/resolvers/model_errors.rb

@@ -0,0 +1,39 @@
+# frozen_string_literal: true
+module Resolvers
+  class ModelErrors
+    attr_reader :full_messages, :field_name, :messages, :path
+
+    def initialize(args)
+      @full_messages = args[:full_messages]
+      @field_name = args[:field_name]
+      @messages = args[:messages]
+      @path = args[:path]
+    end
+
+    def self.from_active_record_model(model)
+      return if model&.errors.blank?
+
+      model.errors.messages.map do |field, messages|
+        new(
+          full_messages: model.errors.full_messages_for(field),
+          field_name: field,
+          messages: messages,
+          path: ["attributes", field]
+        )
+      end
+    end
+
+    def self.from_active_record_model_errors(errors)
+      return if errors.blank?
+
+      errors.messages.map do |field, messages|
+        new(
+          full_messages: errors.full_messages_for(field),
+          field_name: field,
+          messages: messages,
+          path: ["attributes", field]
+        )
+      end
+    end
+  end
+end

app/graphql/types/buy_crypto_order_type.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+module Types
+  class BuyCryptoOrderType < Types::BaseObject
+    implements GraphQL::Types::Relay::Node
+    global_id_field :id
+
+    graphql_name "BuyCryptoOrder"
+
+    field :id, ID, null: false
+
+    field :currency, CurrencyType, null: false
+    def currency
+      dataloader.with(Dataloader::Source, Currency).load(object.currency_id)
+    end
+
+    field :status, ProcessStatusEnum, null: false
+    field :paid_amount_cents, Integer, null: false
+    field :received_amount, String, null: true
+    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
+  end
+end

app/graphql/types/fiat_balance_type.rb

@@ -9,7 +9,5 @@ module Types
     field :id, ID, null: false
     field :amount_cents, Integer, null: false
     field :amount_currency, String, null: false
-    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
-    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
   end
 end

app/graphql/types/mutation_type.rb

@@ -1,5 +1,7 @@
 # frozen_string_literal: true
 module Types
   class MutationType < Types::BaseObject
+    field :create_sell_crypto_order, mutation: Mutations::CreateSellCryptoOrder
+    field :create_buy_crypto_order, mutation: Mutations::CreateBuyCryptoOrder
   end
 end

app/graphql/types/process_status_enum.rb

@@ -0,0 +1,10 @@
+# frozen_string_literal: true
+module Types
+  class ProcessStatusEnum < Types::BaseEnum
+    graphql_name "ProcessStatus"
+
+    value "PROCESSING", value: "processing"
+    value "COMPLETED", value: "completed"
+    value "CANCELED", value: "canceled"
+  end
+end

app/graphql/types/query_type.rb

@@ -18,5 +18,15 @@ module Types
     def fiat_balances
       Pundit.policy_scope(current_user, FiatBalance)
     end
+
+    field :sell_crypto_orders, SellCryptoOrderType.connection_type, null: false
+    def sell_crypto_orders
+      []
+    end
+
+    field :buy_crypto_orders, BuyCryptoOrderType.connection_type, null: false
+    def buy_crypto_orders
+      []
+    end
   end
 end

app/graphql/types/record_invalid_type.rb

@@ -0,0 +1,11 @@
+# frozen_string_literal: true
+
+module Types
+  class RecordInvalidType < Types::BaseObject
+    graphql_name "RecordInvalid"
+    field :full_messages, [String], null: false
+    field :field_name, String, null: true
+    field :messages, [String], null: true
+    field :path, [String], null: true
+  end
+end

app/graphql/types/sell_crypto_order_type.rb

@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+module Types
+  class SellCryptoOrderType < Types::BaseObject
+    implements GraphQL::Types::Relay::Node
+    global_id_field :id
+
+    graphql_name "SellCryptoOrder"
+
+    field :id, ID, null: false
+
+    field :currency, CurrencyType, null: false
+    def currency
+      dataloader.with(Dataloader::Source, Currency).load(object.currency_id)
+    end
+
+    field :status, ProcessStatusEnum, null: false
+    field :paid_amount, String, null: false
+    field :received_amount_cents, Integer, null: true
+    field :created_at, GraphQL::Types::ISO8601DateTime, null: false
+    field :updated_at, GraphQL::Types::ISO8601DateTime, null: false
+  end
+end

app/graphql/x_stake_schema.rb

@@ -1,6 +1,6 @@
 # frozen_string_literal: true
 class XStakeSchema < GraphQL::Schema
-  # mutation(Types::MutationType)
+  mutation(Types::MutationType)
   query(Types::QueryType)
   use GraphQL::Dataloader
 

app/javascript/__generated__/schema.graphql

@@ -34,19 +34,24 @@ type BalanceEdge {
   node: Balance!
 }
 
-type Currency implements Node {
+type BuyCryptoOrder implements Node {
+  createdAt: ISO8601DateTime!
+  currency: Currency!
   id: ID!
-  name: String!
+  paidAmountCents: Int!
+  receivedAmount: Float
+  status: ProcessStatus!
+  updatedAt: ISO8601DateTime!
 }
 
 """
-The connection type for Currency.
+The connection type for BuyCryptoOrder.
 """
-type CurrencyConnection {
+type BuyCryptoOrderConnection {
   """
   A list of edges.
   """
-  edges: [CurrencyEdge!]!
+  edges: [BuyCryptoOrderEdge!]!
 
   """
   Information to aid in pagination.
@@ -57,7 +62,7 @@ type CurrencyConnection {
 """
 An edge in a connection.
 """
-type CurrencyEdge {
+type BuyCryptoOrderEdge {
   """
   A cursor for use in pagination.
   """
@@ -66,7 +71,82 @@ type CurrencyEdge {
   """
   The item at the end of the edge.
   """
-  node: Currency!
+  node: BuyCryptoOrder!
+}
+
+input CreateBuyCryptoOrderAttributesInput {
+  """
+  Amount to be paid
+  """
+  amount: Float!
+  currencyId: ID!
+}
+
+"""
+Autogenerated input type of CreateBuyCryptoOrder
+"""
+input CreateBuyCryptoOrderInput {
+  """
+  A unique identifier for the client performing the mutation.
+  """
+  clientMutationId: String
+  order: CreateBuyCryptoOrderAttributesInput!
+}
+
+"""
+Autogenerated return type of CreateBuyCryptoOrder
+"""
+type CreateBuyCryptoOrderPayload {
+  """
+  A unique identifier for the client performing the mutation.
+  """
+  clientMutationId: String
+
+  """
+  Errors encountered during execution of the mutation.
+  """
+  errors: [String!]
+  order: BuyCryptoOrder!
+}
+
+input CreateSellCryptoOrderAttributesInput {
+  """
+  Amount to be paid
+  """
+  amount: Float!
+  currencyId: ID!
+}
+
+"""
+Autogenerated input type of CreateSellCryptoOrder
+"""
+input CreateSellCryptoOrderInput {
+  """
+  A unique identifier for the client performing the mutation.
+  """
+  clientMutationId: String
+  order: CreateSellCryptoOrderAttributesInput!
+}
+
+"""
+Autogenerated return type of CreateSellCryptoOrder
+"""
+type CreateSellCryptoOrderPayload {
+  """
+  A unique identifier for the client performing the mutation.
+  """
+  clientMutationId: String
+
+  """
+  Errors encountered during execution of the mutation.
+  """
+  errors: [String!]
+  order: SellCryptoOrder!
+}
+
+type Currency implements Node {
+  id: ID!
+  name: String!
 }
 
 type FiatBalance implements Node {
@@ -112,6 +192,21 @@ An ISO 8601-encoded datetime
 """
 scalar ISO8601DateTime
 
+type Mutation {
+  createBuyCryptoOrder(
+    """
+    Parameters for CreateBuyCryptoOrder
+    """
+    input: CreateBuyCryptoOrderInput!
+  ): CreateBuyCryptoOrderPayload
+  createSellCryptoOrder(
+    """
+    Parameters for CreateSellCryptoOrder
+    """
+    input: CreateSellCryptoOrderInput!
+  ): CreateSellCryptoOrderPayload
+}
+
 """
 An object with an ID.
 """
@@ -147,6 +242,12 @@ type PageInfo {
   startCursor: String
 }
 
+enum ProcessStatus {
+  CANCELED
+  COMPLETED
+  PROCESSING
+}
+
 type Query {
   balances(
     """
@@ -169,7 +270,7 @@ type Query {
     """
     last: Int
   ): BalanceConnection!
-  currencies(
+  buyCryptoOrders(
     """
     Returns the elements in the list that come after the specified cursor.
     """
@@ -189,7 +290,7 @@ type Query {
     Returns the last _n_ elements from the list.
     """
     last: Int
-  ): CurrencyConnection!
+  ): BuyCryptoOrderConnection!
   currentUser: User
   fiatBalances(
     """
@@ -232,6 +333,67 @@ type Query {
     """
     ids: [ID!]!
   ): [Node]!
+  sellCryptoOrders(
+    """
+    Returns the elements in the list that come after the specified cursor.
+    """
+    after: String
+
+    """
+    Returns the elements in the list that come before the specified cursor.
+    """
+    before: String
+
+    """
+    Returns the first _n_ elements from the list.
+    """
+    first: Int
+
+    """
+    Returns the last _n_ elements from the list.
+    """
+    last: Int
+  ): SellCryptoOrderConnection!
+}
+
+type SellCryptoOrder implements Node {
+  createdAt: ISO8601DateTime!
+  currency: Currency!
+  id: ID!
+  paidAmount: Float!
+  receivedAmountCents: Int
+  status: ProcessStatus!
+  updatedAt: ISO8601DateTime!
+}
+
+"""
+The connection type for SellCryptoOrder.
+"""
+type SellCryptoOrderConnection {
+  """
+  A list of edges.
+  """
+  edges: [SellCryptoOrderEdge!]!
+
+  """
+  Information to aid in pagination.
+  """
+  pageInfo: PageInfo!
+}
+
+"""
+An edge in a connection.
+"""
+type SellCryptoOrderEdge {
+  """
+  A cursor for use in pagination.
+  """
+  cursor: String!
+
+  """
+  The item at the end of the edge.
+  """
+  node: SellCryptoOrder!
 }
 
 type User {

app/models/balance.rb

@@ -25,5 +25,13 @@ class Balance < ApplicationRecord
   belongs_to :user
   belongs_to :currency
 
-  validates :amount, presence: true
+  validates :amount, presence: true, numericality: { greater_than_or_equal_to: 0 }
+
+  def withdrawal!(value)
+    update!(amount: amount - value)
+  end
+
+  def deposit!(value)
+    update!(amount: amount + value)
+  end
 end

app/models/fiat_balance.rb

@@ -24,7 +24,17 @@ class FiatBalance < ApplicationRecord
 
   monetize :amount_cents
 
+  validates :amount_cents, numericality: { greater_than_or_equal_to: 0 }
+
   def amount_formatted
     amount.format
   end
+
+  def withdrawal!(value)
+    update!(amount_cents: amount_cents - value)
+  end
+
+  def deposit!(value)
+    update!(amount_cents: amount_cents + value)
+  end
 end

app/models/user.rb

@@ -25,7 +25,7 @@ class User < ApplicationRecord
     :recoverable, :rememberable, :validatable
 
   has_many :documents, class_name: "UserDocument", dependent: :destroy
-  has_one :balance, dependent: :restrict_with_error
+  has_many :balances, dependent: :restrict_with_error
   has_one :fiat_balance, dependent: :restrict_with_error
 
   validates :first_name, :last_name, :email, presence: true