refactors data access layer to use pop ORM for eager loading, adds book titles rented to renters in response body

2020-05-31 00:40:32 -04:00
parent a06b4d70ab
commit 28e52a4e08
29 changed files with 732 additions and 287 deletions
@@ -0,0 +1,8 @@
+package rental
+
+import "errors"
+
+var (
+	ErrInvalidBook     = errors.New("book not supported in library")
+	ErrUnavailableBook = errors.New("book is not available at this library")
+)
@@ -0,0 +1,65 @@
+package rental
+
+import (
+	"fmt"
+
+	"github.com/gofrs/uuid"
+)
+
+// Storage defines behavior for interacting with the inventory store.
+type Storage interface {
+	IsBookAvailable(title string) (available bool, err error)
+	RenterAlreadyCheckedOut(renterId uuid.UUID, title string) (checkedOut bool, err error)
+	CheckoutBook(renterId uuid.UUID, title string) error
+	ReturnBook(renterId uuid.UUID, title string) error
+}
+
+type service struct {
+	store Storage
+}
+
+// Service defines behavior for interacting with the inventory service.
+type Service interface {
+	IsBookAvailable(title string) (available bool, err error)
+	CheckoutBook(renterId uuid.UUID, title string) error
+	ReturnBook(renterId uuid.UUID, title string) error
+}
+
+// NewService creates a new inventory service.
+func NewService(s Storage) *service {
+	return &service{
+		s,
+	}
+}
+
+// IsBookAvailable checks if a book is available to rent at this library.
+func (s *service) IsBookAvailable(title string) (available bool, err error) {
+	return s.store.IsBookAvailable(title)
+}
+
+// CheckoutBook checks a book out to a renter.
+func (s *service) CheckoutBook(renterId uuid.UUID, title string) error {
+	available, err := s.IsBookAvailable(title)
+	if err != nil {
+		return err
+	}
+
+	if !available {
+		return ErrUnavailableBook
+	}
+
+	checkedOut, err := s.store.RenterAlreadyCheckedOut(renterId, title)
+	// If there was an error or the book is checked out by the renter already we'll
+	// say the book is unavailable.
+	if err != nil || checkedOut {
+		fmt.Println("unavailable book", err, checkedOut)
+		return ErrUnavailableBook
+	}
+
+	return s.store.CheckoutBook(renterId, title)
+}
+
+// ReturnBook returns a book for a renter.
+func (s *service) ReturnBook(renterId uuid.UUID, title string) error {
+	return s.store.ReturnBook(renterId, title)
+}
@@ -0,0 +1,158 @@
+// Code generated by MockGen. DO NOT EDIT.
+// Source: rental.go
+
+// Package rental is a generated GoMock package.
+package rental
+
+import (
+	uuid "github.com/gofrs/uuid"
+	gomock "github.com/golang/mock/gomock"
+	reflect "reflect"
+)
+
+// MockStorage is a mock of Storage interface
+type MockStorage struct {
+	ctrl     *gomock.Controller
+	recorder *MockStorageMockRecorder
+}
+
+// MockStorageMockRecorder is the mock recorder for MockStorage
+type MockStorageMockRecorder struct {
+	mock *MockStorage
+}
+
+// NewMockStorage creates a new mock instance
+func NewMockStorage(ctrl *gomock.Controller) *MockStorage {
+	mock := &MockStorage{ctrl: ctrl}
+	mock.recorder = &MockStorageMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use
+func (m *MockStorage) EXPECT() *MockStorageMockRecorder {
+	return m.recorder
+}
+
+// IsBookAvailable mocks base method
+func (m *MockStorage) IsBookAvailable(title string) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "IsBookAvailable", title)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// IsBookAvailable indicates an expected call of IsBookAvailable
+func (mr *MockStorageMockRecorder) IsBookAvailable(title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "IsBookAvailable", reflect.TypeOf((*MockStorage)(nil).IsBookAvailable), title)
+}
+
+// RenterAlreadyCheckedOut mocks base method
+func (m *MockStorage) RenterAlreadyCheckedOut(renterId uuid.UUID, title string) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "RenterAlreadyCheckedOut", renterId, title)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// RenterAlreadyCheckedOut indicates an expected call of RenterAlreadyCheckedOut
+func (mr *MockStorageMockRecorder) RenterAlreadyCheckedOut(renterId, title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "RenterAlreadyCheckedOut", reflect.TypeOf((*MockStorage)(nil).RenterAlreadyCheckedOut), renterId, title)
+}
+
+// CheckoutBook mocks base method
+func (m *MockStorage) CheckoutBook(renterId uuid.UUID, title string) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "CheckoutBook", renterId, title)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// CheckoutBook indicates an expected call of CheckoutBook
+func (mr *MockStorageMockRecorder) CheckoutBook(renterId, title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CheckoutBook", reflect.TypeOf((*MockStorage)(nil).CheckoutBook), renterId, title)
+}
+
+// ReturnBook mocks base method
+func (m *MockStorage) ReturnBook(renterId uuid.UUID, title string) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "ReturnBook", renterId, title)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// ReturnBook indicates an expected call of ReturnBook
+func (mr *MockStorageMockRecorder) ReturnBook(renterId, title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ReturnBook", reflect.TypeOf((*MockStorage)(nil).ReturnBook), renterId, title)
+}
+
+// MockService is a mock of Service interface
+type MockService struct {
+	ctrl     *gomock.Controller
+	recorder *MockServiceMockRecorder
+}
+
+// MockServiceMockRecorder is the mock recorder for MockService
+type MockServiceMockRecorder struct {
+	mock *MockService
+}
+
+// NewMockService creates a new mock instance
+func NewMockService(ctrl *gomock.Controller) *MockService {
+	mock := &MockService{ctrl: ctrl}
+	mock.recorder = &MockServiceMockRecorder{mock}
+	return mock
+}
+
+// EXPECT returns an object that allows the caller to indicate expected use
+func (m *MockService) EXPECT() *MockServiceMockRecorder {
+	return m.recorder
+}
+
+// IsBookAvailable mocks base method
+func (m *MockService) IsBookAvailable(title string) (bool, error) {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "IsBookAvailable", title)
+	ret0, _ := ret[0].(bool)
+	ret1, _ := ret[1].(error)
+	return ret0, ret1
+}
+
+// IsBookAvailable indicates an expected call of IsBookAvailable
+func (mr *MockServiceMockRecorder) IsBookAvailable(title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "IsBookAvailable", reflect.TypeOf((*MockService)(nil).IsBookAvailable), title)
+}
+
+// CheckoutBook mocks base method
+func (m *MockService) CheckoutBook(renterId uuid.UUID, title string) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "CheckoutBook", renterId, title)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// CheckoutBook indicates an expected call of CheckoutBook
+func (mr *MockServiceMockRecorder) CheckoutBook(renterId, title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "CheckoutBook", reflect.TypeOf((*MockService)(nil).CheckoutBook), renterId, title)
+}
+
+// ReturnBook mocks base method
+func (m *MockService) ReturnBook(renterId uuid.UUID, title string) error {
+	m.ctrl.T.Helper()
+	ret := m.ctrl.Call(m, "ReturnBook", renterId, title)
+	ret0, _ := ret[0].(error)
+	return ret0
+}
+
+// ReturnBook indicates an expected call of ReturnBook
+func (mr *MockServiceMockRecorder) ReturnBook(renterId, title interface{}) *gomock.Call {
+	mr.mock.ctrl.T.Helper()
+	return mr.mock.ctrl.RecordCallWithMethodType(mr.mock, "ReturnBook", reflect.TypeOf((*MockService)(nil).ReturnBook), renterId, title)
+}
@@ -0,0 +1,158 @@
+package rental
+
+import (
+	"errors"
+	"testing"
+
+	"github.com/gofrs/uuid"
+	"github.com/golang/mock/gomock"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestRental_IsBookAvailable(t *testing.T) {
+	testCases := []struct {
+		TestName  string
+		Title     string
+		Available bool
+		Error     error
+	}{
+		{
+			TestName:  "success-available",
+			Title:     "Book #1",
+			Available: true,
+		},
+		{
+			TestName:  "success-unavailable",
+			Title:     "Book #2",
+			Available: false,
+		},
+		{
+			TestName: "failure",
+			Title:    "Book #3",
+			Error:    errors.New("test error"),
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.TestName, func(t *testing.T) {
+			ctrl := gomock.NewController(t)
+			defer ctrl.Finish()
+
+			mockStorage := NewMockStorage(ctrl)
+			mockStorage.EXPECT().IsBookAvailable(tc.Title).Return(tc.Available, tc.Error)
+
+			service := NewService(mockStorage)
+			available, err := service.IsBookAvailable(tc.Title)
+
+			assert.Equal(t, tc.Available, available)
+			assert.Equal(t, tc.Error, err)
+		})
+	}
+}
+
+func TestRental_CheckoutBook(t *testing.T) {
+	testCases := []struct {
+		TestName        string
+		Title           string
+		Available       bool
+		AvailableError  error
+		CheckedOut      bool
+		CheckedOutError error
+		Error           error
+	}{
+		{
+			TestName:  "success",
+			Title:     "Book #1",
+			Available: true,
+		},
+		{
+			TestName:  "unavailable",
+			Title:     "Book #2",
+			Available: false,
+			Error:     ErrUnavailableBook,
+		},
+		{
+			TestName:       "availability_error",
+			Title:          "Book #3",
+			AvailableError: errors.New("test error"),
+			Error:          errors.New("test error"),
+		},
+		{
+			TestName:   "checked-out",
+			Title:      "Book #4",
+			Available:  true,
+			CheckedOut: true,
+			Error:      ErrUnavailableBook,
+		},
+		{
+			TestName:  "failure",
+			Title:     "Book #4",
+			Available: true,
+			Error:     errors.New("test error"),
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.TestName, func(t *testing.T) {
+			ctrl := gomock.NewController(t)
+			defer ctrl.Finish()
+
+			renterId, err := uuid.NewV4()
+			if err != nil {
+				t.Error(err)
+			}
+
+			mockStorage := NewMockStorage(ctrl)
+			mockStorage.EXPECT().IsBookAvailable(tc.Title).Return(tc.Available, tc.AvailableError)
+			if tc.Available && tc.AvailableError == nil {
+				mockStorage.EXPECT().RenterAlreadyCheckedOut(renterId, tc.Title).Return(tc.CheckedOut, tc.CheckedOutError)
+				if !tc.CheckedOut && tc.CheckedOutError == nil {
+					mockStorage.EXPECT().CheckoutBook(renterId, tc.Title).Return(tc.Error)
+				}
+			}
+
+			service := NewService(mockStorage)
+			err = service.CheckoutBook(renterId, tc.Title)
+
+			assert.Equal(t, tc.Error, err)
+		})
+	}
+}
+
+func TestRental_ReturnBook(t *testing.T) {
+	testCases := []struct {
+		TestName string
+		Title    string
+		Error    error
+	}{
+		{
+			TestName: "success",
+			Title:    "Book #1",
+		},
+		{
+			TestName: "failure",
+			Title:    "Book #2",
+			Error:    errors.New("test error"),
+		},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.TestName, func(t *testing.T) {
+			ctrl := gomock.NewController(t)
+			defer ctrl.Finish()
+
+			renterId, err := uuid.NewV4()
+			if err != nil {
+				t.Error(err)
+			}
+
+			mockStorage := NewMockStorage(ctrl)
+			mockStorage.EXPECT().ReturnBook(renterId, tc.Title).Return(tc.Error)
+
+			service := NewService(mockStorage)
+			err = service.ReturnBook(renterId, tc.Title)
+
+			assert.Equal(t, tc.Error, err)
+		})
+	}
+}