feat: implement repo expense methods

README.md

@@ -564,3 +564,16 @@ querier.
 Since this repo layer is just a wrapping layer between the `sqlc.models` and
 my own models, I can extract the conversion part to functions and test them.
 I'm not testing the whole thing but I test what I can.
+
+### 2024/10/24
+
+When writing the tests. I am asking myself the differences between `[]T`,
+`[]*T` and `*[]T`.
+
+`*[]T` is simple, it is a reference to the original slice. So modifying it
+means modifying the original slice.
+
+But between `[]*T` and `[]T`, the only difference that I see (pointed out by
+`ChatGPT`) is how the memory is allocated. With `[]T` it might be better for
+the GC to deal with the memory free. I thing for my project I will stick to
+`[]T`.

internal/howmuch/adapter/repo/event.go

@@ -35,7 +35,7 @@ import (
 )
 
 type eventRepository struct {
-	queries sqlc.Querier
+	queries *sqlc.Queries
 }
 
 func NewEventRepository(db *sql.DB) repo.EventRepository {
@@ -62,7 +62,7 @@ func convToEventRetrieved(eventDTO *sqlc.GetEventByIDRow) (*model.EventRetrieved
 		return nil, err
 	}
 
-	var users []*model.UserBaseRetrieved
+	var users []model.UserBaseRetrieved
 	err = json.Unmarshal(eventDTO.Users, &users)
 	if err != nil {
 		// Unexpected
@@ -99,8 +99,8 @@ func (e *eventRepository) GetByID(ctx context.Context, eventID int) (*model.Even
 	return convToEventRetrieved(&eventDTO)
 }
 
-func convToEventList(eventsDTO []sqlc.ListEventsByUserIDRow) ([]*model.EventListRetrieved, error) {
+func convToEventList(eventsDTO []sqlc.ListEventsByUserIDRow) ([]model.EventListRetrieved, error) {
-	var events []*model.EventListRetrieved
+	var events []model.EventListRetrieved
 
 	for _, evDTO := range eventsDTO {
 		var owner model.UserBaseRetrieved
@@ -110,10 +110,12 @@ func convToEventList(eventsDTO []sqlc.ListEventsByUserIDRow) ([]*model.EventList
 			log.ErrorLog("json unmarshal error", "err", err)
 			return nil, err
 		}
-		ev := &model.EventListRetrieved{
+		ev := model.EventListRetrieved{
 			ID:          int(evDTO.ID),
 			Name:        evDTO.Name,
 			Description: evDTO.Description.String,
+			Owner:       &owner,
+			CreatedAt:   evDTO.CreatedAt,
 		}
 
 		events = append(events, ev)
@@ -126,7 +128,7 @@ func convToEventList(eventsDTO []sqlc.ListEventsByUserIDRow) ([]*model.EventList
 func (e *eventRepository) ListEventsByUserID(
 	ctx context.Context,
 	userID int,
-) ([]*model.EventListRetrieved, error) {
+) ([]model.EventListRetrieved, error) {
 	eventsDTO, err := e.queries.ListEventsByUserID(ctx, int32(userID))
 	if err != nil {
 		log.ErrorLog("query error", "err", err)

internal/howmuch/adapter/repo/event_test.go

@@ -0,0 +1,122 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package repo
+
+import (
+	"database/sql"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/adapter/repo/sqlc"
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/model"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestConvToEventRetrieved(t *testing.T) {
+	input := &sqlc.GetEventByIDRow{
+		ID:              123,
+		Name:            "event",
+		Description:     sql.NullString{Valid: false},
+		TotalAmount:     sql.NullInt32{Valid: false},
+		DefaultCurrency: "EUR",
+		CreatedAt:       time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		UpdatedAt:       time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		Owner:           json.RawMessage(`{"id":1, "first_name":"owner", "last_name":"owner"}`),
+		Users:           json.RawMessage(`[{"id":1, "first_name":"owner", "last_name":"owner"}]`),
+	}
+
+	want := &model.EventRetrieved{
+		ID:              123,
+		Name:            "event",
+		Description:     "",
+		TotalAmount:     model.Money{Amount: 0, Currency: "EUR"},
+		DefaultCurrency: model.Currency("EUR"),
+		CreatedAt:       time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		UpdatedAt:       time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		Owner: &model.UserBaseRetrieved{
+			ID:        1,
+			FirstName: "owner",
+			LastName:  "owner",
+		},
+		Users: []model.UserBaseRetrieved{
+			{
+				ID:        1,
+				FirstName: "owner",
+				LastName:  "owner",
+			},
+		},
+	}
+
+	got, err := convToEventRetrieved(input)
+	assert.NoError(t, err)
+	assert.Equal(t, want, got)
+}
+
+func TestConvToEventList(t *testing.T) {
+	input := []sqlc.ListEventsByUserIDRow{
+		{
+			ID:          123,
+			Name:        "event",
+			Description: sql.NullString{Valid: false},
+			CreatedAt:   time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+			Owner:       json.RawMessage(`{"id":1, "first_name":"owner", "last_name":"owner"}`),
+		},
+		{
+			ID:          456,
+			Name:        "event2",
+			Description: sql.NullString{String: "super event", Valid: true},
+			CreatedAt:   time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+			Owner:       json.RawMessage(`{"id":1, "first_name":"owner", "last_name":"owner"}`),
+		},
+	}
+
+	want := []model.EventListRetrieved{
+		{
+			ID:          123,
+			Name:        "event",
+			Description: "",
+			CreatedAt:   time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+			Owner: &model.UserBaseRetrieved{
+				ID:        1,
+				FirstName: "owner",
+				LastName:  "owner",
+			},
+		},
+		{
+			ID:          456,
+			Name:        "event2",
+			Description: "super event",
+			CreatedAt:   time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+			Owner: &model.UserBaseRetrieved{
+				ID:        1,
+				FirstName: "owner",
+				LastName:  "owner",
+			},
+		},
+	}
+
+	got, err := convToEventList(input)
+	assert.NoError(t, err)
+	assert.Equal(t, want, got)
+}

internal/howmuch/adapter/repo/expense.go

@@ -0,0 +1,231 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package repo
+
+import (
+	"context"
+	"database/sql"
+	"encoding/json"
+	"time"
+
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/adapter/repo/sqlc"
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/model"
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/usecase/repo"
+	"git.vinchent.xyz/vinchent/howmuch/internal/pkg/log"
+)
+
+type expenseRepository struct {
+	queries *sqlc.Queries
+}
+
+func NewExpenseRepository(db *sql.DB) repo.ExpenseRepository {
+	return &expenseRepository{
+		queries: sqlc.New(db),
+	}
+}
+
+// DeleteExpense implements repo.ExpenseRepository.
+func (e *expenseRepository) DeleteExpense(ctx context.Context, expenseID int) error {
+	return e.queries.DeleteExpense(ctx, int32(expenseID))
+}
+
+// DeleteTransactionsOfExpense implements repo.ExpenseRepository.
+func (e *expenseRepository) DeleteTransactionsOfExpense(ctx context.Context, expenseID int) error {
+	return e.queries.DeleteTransactionsOfExpenseID(ctx, int32(expenseID))
+}
+
+// GetExpenseByID implements repo.ExpenseRepository.
+func (e *expenseRepository) GetExpenseByID(
+	ctx context.Context,
+	expenseID int,
+) (*model.ExpenseRetrieved, error) {
+	expenseDTO, err := e.queries.GetExpenseByID(ctx, int32(expenseID))
+	if err != nil {
+		return nil, err
+	}
+	expense, err := convToExpenseRetrieved(&expenseDTO)
+	if err != nil {
+		return nil, err
+	}
+	return expense, nil
+}
+
+func convToPayments(raw json.RawMessage) ([]model.Payment, error) {
+	var paymentsRetrieved []model.PaymentRetrieved
+	err := json.Unmarshal(raw, &paymentsRetrieved)
+	if err != nil {
+		// Unexpected
+		log.ErrorLog("json unmarshal error", "err", err)
+		return nil, err
+	}
+
+	var payments []model.Payment
+	for _, p := range paymentsRetrieved {
+		payment := model.Payment{
+			PayerID:        p.PayerID,
+			PayerFirstName: p.PayerFirstName,
+			PayerLastName:  p.PayerLastName,
+			Amount:         model.MakeMoney(p.Amount, model.Currency(p.Currency)),
+		}
+		payments = append(payments, payment)
+	}
+
+	return payments, nil
+}
+
+func convToBenefits(raw json.RawMessage) ([]model.Benefit, error) {
+	var benefitsRetrieved []model.BenefitRetrieved
+	err := json.Unmarshal(raw, &benefitsRetrieved)
+	if err != nil {
+		// Unexpected
+		log.ErrorLog("json unmarshal error", "err", err)
+		return nil, err
+	}
+
+	var benefits []model.Benefit
+	for _, b := range benefitsRetrieved {
+		benefit := model.Benefit{
+			RecipientID:        b.RecipientID,
+			RecipientFirstName: b.RecipientFirstName,
+			RecipientLastName:  b.RecipientLastName,
+			Amount:             model.MakeMoney(b.Amount, model.Currency(b.Currency)),
+		}
+		benefits = append(benefits, benefit)
+	}
+
+	return benefits, nil
+}
+
+func convToExpenseRetrieved(expenseDTO *sqlc.GetExpenseByIDRow) (*model.ExpenseRetrieved, error) {
+	payments, err := convToPayments(expenseDTO.Payments)
+	if err != nil {
+		// Unexpected
+		return nil, err
+	}
+
+	benefits, err := convToBenefits(expenseDTO.Benefits)
+	if err != nil {
+		// Unexpected
+		return nil, err
+	}
+
+	expenseRetrieved := &model.ExpenseRetrieved{
+		ID:        int(expenseDTO.ID),
+		CreatedAt: expenseDTO.CreatedAt,
+		UpdatedAt: expenseDTO.UpdatedAt,
+		Amount:    model.MakeMoney(int(expenseDTO.Amount), model.Currency(expenseDTO.Currency)),
+		EventID:   int(expenseDTO.EventID),
+		Detail: model.ExpenseDetail{
+			Name:  expenseDTO.Name.String,
+			Place: expenseDTO.Place.String,
+		},
+		Payments: payments,
+		Benefits: benefits,
+	}
+
+	return expenseRetrieved, nil
+}
+
+// InsertExpense implements repo.ExpenseRepository.
+func (e *expenseRepository) InsertExpense(
+	ctx context.Context,
+	expenseEntity *model.ExpenseEntity,
+) (*model.ExpenseEntity, error) {
+	expenseDTO, err := e.queries.InsertExpense(ctx, sqlc.InsertExpenseParams{
+		CreatedAt: time.Now(),
+		UpdatedAt: time.Now(),
+		Amount:    int32(expenseEntity.Amount),
+		Currency:  expenseEntity.Currency,
+		EventID:   int32(expenseEntity.EventID),
+		Name:      sql.NullString{String: expenseEntity.Name, Valid: true},
+		Place:     sql.NullString{String: expenseEntity.Place, Valid: true},
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &model.ExpenseEntity{
+		ID:        int(expenseDTO.ID),
+		CreatedAt: expenseDTO.CreatedAt,
+		UpdatedAt: expenseDTO.CreatedAt,
+		Amount:    int(expenseDTO.Amount),
+		Currency:  expenseDTO.Currency,
+		EventID:   int(expenseDTO.EventID),
+		Name:      expenseDTO.Name.String,
+		Place:     expenseDTO.Place.String,
+	}, nil
+}
+
+// ListExpensesByEventID implements repo.ExpenseRepository.
+func (e *expenseRepository) ListExpensesByEventID(
+	ctx context.Context,
+	id int,
+) ([]model.ExpensesListRetrieved, error) {
+	listDTO, err := e.queries.ListExpensesByEventID(ctx, int32(id))
+	if err != nil {
+		return nil, err
+	}
+	var res []model.ExpensesListRetrieved
+	for _, dto := range listDTO {
+		elem := model.ExpensesListRetrieved{
+			ID:        int(dto.ID),
+			CreatedAt: dto.CreatedAt,
+			UpdatedAt: dto.UpdatedAt,
+			Amount:    model.MakeMoney(int(dto.Amount), model.Currency(dto.Currency)),
+			EventID:   int(dto.EventID),
+			Detail: model.ExpenseDetail{
+				Name:  dto.Name.String,
+				Place: dto.Place.String,
+			},
+		}
+		res = append(res, elem)
+	}
+	return res, nil
+}
+
+// UpdateExpenseByID implements repo.ExpenseRepository.
+func (e *expenseRepository) UpdateExpenseByID(
+	ctx context.Context,
+	expenseUpdate *model.ExpenseUpdateEntity,
+) (*model.ExpenseEntity, error) {
+	expenseDTO, err := e.queries.UpdateExpenseByID(ctx, sqlc.UpdateExpenseByIDParams{
+		ID:        int32(expenseUpdate.ID),
+		UpdatedAt: time.Now(),
+		Amount:    int32(expenseUpdate.Amount),
+		Currency:  expenseUpdate.Currency,
+		Name:      sql.NullString{String: expenseUpdate.Name, Valid: true},
+		Place:     sql.NullString{String: expenseUpdate.Place, Valid: true},
+	})
+	if err != nil {
+		return nil, err
+	}
+	return &model.ExpenseEntity{
+		ID:        int(expenseDTO.ID),
+		CreatedAt: expenseDTO.CreatedAt,
+		UpdatedAt: expenseDTO.CreatedAt,
+		Amount:    int(expenseDTO.Amount),
+		Currency:  expenseDTO.Currency,
+		EventID:   int(expenseDTO.EventID),
+		Name:      expenseDTO.Name.String,
+		Place:     expenseDTO.Place.String,
+	}, nil
+}

internal/howmuch/adapter/repo/expense_test.go

@@ -0,0 +1,96 @@
+// MIT License
+//
+// Copyright (c) 2024 vinchent <vinchent@vinchent.xyz>
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in all
+// copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+// SOFTWARE.
+
+package repo
+
+import (
+	"database/sql"
+	"encoding/json"
+	"testing"
+	"time"
+
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/adapter/repo/sqlc"
+	"git.vinchent.xyz/vinchent/howmuch/internal/howmuch/model"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestConvToExpenseRetrieved(t *testing.T) {
+	input := &sqlc.GetExpenseByIDRow{
+		ID:        123,
+		CreatedAt: time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		UpdatedAt: time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		Amount:    123,
+		Currency:  "EUR",
+		EventID:   123,
+		Name:      sql.NullString{Valid: false},
+		Place:     sql.NullString{Valid: false},
+		Payments: json.RawMessage(
+			`[{"payer_id": 1, "payer_first_name": "toto", "payer_last_name": "titi", "amount": 10, "currency": "EUR"},
+            {"payer_id": 2, "payer_first_name": "tata", "payer_last_name": "titi", "amount": 10, "currency": "EUR"}]`,
+		),
+		Benefits: json.RawMessage(
+			`[{"recipient_id": 1, "recipient_first_name": "toto", "recipient_last_name": "titi", "amount": 10, "currency": "EUR"},
+            {"recipient_id": 2, "recipient_first_name": "tata", "recipient_last_name": "titi", "amount": 10, "currency": "EUR"}]`,
+		),
+	}
+
+	want := &model.ExpenseRetrieved{
+		ID:        123,
+		CreatedAt: time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		UpdatedAt: time.Date(2000, time.April, 11, 0, 0, 0, 0, time.UTC),
+		Amount:    model.Money{Amount: 123, Currency: model.Currency("EUR")},
+		EventID:   123,
+		Detail:    model.ExpenseDetail{},
+		Payments: []model.Payment{
+			{
+				PayerID:        1,
+				PayerFirstName: "toto",
+				PayerLastName:  "titi",
+				Amount:         model.Money{Amount: 10, Currency: model.Currency("EUR")},
+			},
+			{
+				PayerID:        2,
+				PayerFirstName: "tata",
+				PayerLastName:  "titi",
+				Amount:         model.Money{Amount: 10, Currency: model.Currency("EUR")},
+			},
+		},
+		Benefits: []model.Benefit{
+			{
+				RecipientID:        1,
+				RecipientFirstName: "toto",
+				RecipientLastName:  "titi",
+				Amount:             model.Money{Amount: 10, Currency: model.Currency("EUR")},
+			},
+			{
+				RecipientID:        2,
+				RecipientFirstName: "tata",
+				RecipientLastName:  "titi",
+				Amount:             model.Money{Amount: 10, Currency: model.Currency("EUR")},
+			},
+		},
+	}
+
+	got, err := convToExpenseRetrieved(input)
+	assert.NoError(t, err)
+	assert.Equal(t, want, got)
+}

internal/howmuch/adapter/repo/sqlc/expense.sql

@@ -24,14 +24,6 @@ FROM "expense" ex
 JOIN "event" ev ON ev.id = ex.event_id
 WHERE ev.id = $1;
 
--- name: ListExpensesByEventIDByUserID :many
-SELECT
-    ex.id, ex.created_at, ex.updated_at, ex.amount, ex.currency, ex.event_id,
-    ex.name, ex.place
-FROM "expense" ex
-JOIN "event" ev ON ev.id = ex.event_id
-WHERE ev.id = $1;
-
 -- name: GetExpenseByID :one
 WITH payer_transaction as (
     SELECT pt.expense_id,

internal/howmuch/adapter/repo/sqlc/expense.sql.go

@@ -183,47 +183,6 @@ func (q *Queries) ListExpensesByEventID(ctx context.Context, id int32) ([]Expens
 	return items, nil
 }
 
-const listExpensesByEventIDByUserID = `-- name: ListExpensesByEventIDByUserID :many
-SELECT
-    ex.id, ex.created_at, ex.updated_at, ex.amount, ex.currency, ex.event_id,
-    ex.name, ex.place
-FROM "expense" ex
-JOIN "event" ev ON ev.id = ex.event_id
-WHERE ev.id = $1
-`
-
-func (q *Queries) ListExpensesByEventIDByUserID(ctx context.Context, id int32) ([]Expense, error) {
-	rows, err := q.db.QueryContext(ctx, listExpensesByEventIDByUserID, id)
-	if err != nil {
-		return nil, err
-	}
-	defer rows.Close()
-	var items []Expense
-	for rows.Next() {
-		var i Expense
-		if err := rows.Scan(
-			&i.ID,
-			&i.CreatedAt,
-			&i.UpdatedAt,
-			&i.Amount,
-			&i.Currency,
-			&i.EventID,
-			&i.Name,
-			&i.Place,
-		); err != nil {
-			return nil, err
-		}
-		items = append(items, i)
-	}
-	if err := rows.Close(); err != nil {
-		return nil, err
-	}
-	if err := rows.Err(); err != nil {
-		return nil, err
-	}
-	return items, nil
-}
-
 const updateExpenseByID = `-- name: UpdateExpenseByID :one
 UPDATE "expense"
 SET updated_at = $2, amount = $3, currency = $4, name = $5, place = $6

internal/howmuch/adapter/repo/sqlc/querier.go

@@ -22,7 +22,6 @@ type Querier interface {
 	InsertUser(ctx context.Context, arg InsertUserParams) (User, error)
 	ListEventsByUserID(ctx context.Context, userID int32) ([]ListEventsByUserIDRow, error)
 	ListExpensesByEventID(ctx context.Context, id int32) ([]Expense, error)
-	ListExpensesByEventIDByUserID(ctx context.Context, id int32) ([]Expense, error)
 	UpdateEventByID(ctx context.Context, arg UpdateEventByIDParams) error
 	UpdateExpenseByID(ctx context.Context, arg UpdateExpenseByIDParams) (Expense, error)
 }

internal/howmuch/adapter/repo/user.go

@@ -34,7 +34,7 @@ import (
 )
 
 type userRepository struct {
-	querier sqlc.Querier
+	querier *sqlc.Queries
 }
 
 const insertTimeout = 1 * time.Second

internal/howmuch/model/event.go

@@ -57,7 +57,7 @@ type EventInfoResponse struct {
 	CreatedAt time.Time
 	UpdatedAt time.Time
 
-	Users []*UserBaseResponse
+	Users []UserBaseResponse
 }
 
 // }}}
@@ -93,7 +93,7 @@ type EventRetrieved struct {
 	Name        string
 	Description string
 
-	Users []*UserBaseRetrieved
+	Users []UserBaseRetrieved
 
 	TotalAmount     Money
 	DefaultCurrency Currency
@@ -121,9 +121,9 @@ type Event struct {
 	Description string
 
 	// lazy get using participation join
-	Users []*UserDO
+	Users []UserDO
 	// lazy get
-	Expenses []*Expense
+	Expenses []Expense
 
 	TotalAmount     Money
 	DefaultCurrency Currency

internal/howmuch/model/expense.go

@@ -37,7 +37,17 @@ type ExpenseRequest struct {
 // }}}
 // {{{ Response
 
-type ExpensesListResponse struct {
+type (
+	ExpenseGetResponse Expense
+	ExpenseResponse    ExpenseRetrieved
+)
+
+// }}}
+// {{{ Retrieved
+
+type ExpenseRetrieved Expense
+
+type ExpensesListRetrieved struct {
 	ID        int       `json:"id"`
 	CreatedAt time.Time `json:"created_at"`
 	UpdatedAt time.Time `json:"updated_at"`
@@ -48,12 +58,21 @@ type ExpensesListResponse struct {
 	Detail ExpenseDetail `json:"detail"`
 }
 
-type ExpenseGetResponse Expense
+type PaymentRetrieved struct {
+	PayerID        int    `json:"payer_id"`
+	PayerFirstName string `json:"payer_first_name"`
+	PayerLastName  string `json:"payer_last_name"`
+	Amount         int    `json:"amount"`
+	Currency       string `json:"currency"`
+}
 
-// }}}
+type BenefitRetrieved struct {
-// {{{ Retrieved
+	RecipientID        int    `json:"recipient_id"`
-
+	RecipientFirstName string `json:"recipient_first_name"`
-type ExpensesListRetrieved ExpensesListResponse
+	RecipientLastName  string `json:"recipient_last_name"`
+	Amount             int    `json:"amount"`
+	Currency           string `json:"currency"`
+}
 
 // }}}
 // {{{ Entity
@@ -72,6 +91,18 @@ type ExpenseEntity struct {
 	Place string
 }
 
+type ExpenseUpdateEntity struct {
+	ID        int
+	UpdatedAt time.Time
+
+	Amount   int
+	Currency string
+
+	// Expense Detail
+	Name  string
+	Place string
+}
+
 // }}}
 // {{{ Domain Models
 

internal/howmuch/usecase/repo/event.go

@@ -37,26 +37,22 @@ type EventRepository interface {
 	GetByID(ctx context.Context, eventID int) (*model.EventRetrieved, error)
 
 	// related to events of a user
-	ListEventsByUserID(ctx context.Context, userID int) ([]*model.EventListRetrieved, error)
+	ListEventsByUserID(ctx context.Context, userID int) ([]model.EventListRetrieved, error)
+
+	// CheckParticipation(ctx context.Context, userID, eventID int) error
 }
 
 type ExpenseRepository interface {
-	Create()
+	DeleteExpense(ctx context.Context, expenseID int) error
-	Update()
+	DeleteTransactionsOfExpense(ctx context.Context, expenseID int) error
-	Delete() // Delete also the related transactions
+	GetExpenseByID(ctx context.Context, expenseID int) (*model.ExpenseRetrieved, error)
-
+	InsertExpense(
-	ListExpensesByUserID()
+		ctx context.Context,
-	GetByID()
+		expenseEntity *model.ExpenseEntity,
-}
+	) (*model.ExpenseEntity, error)
-
+	ListExpensesByEventID(ctx context.Context, id int) ([]model.ExpensesListRetrieved, error)
-type ParticipationRepository interface {
+	UpdateExpenseByID(
-	Create()
+		ctx context.Context,
-	Delete()
+		expenseUpdate *model.ExpenseUpdateEntity,
-	CheckParticipation(ctx context.Context, userID, eventID int) error
+	) (*model.ExpenseEntity, error)
-}
-
-type TransactionRepository interface {
-	Create()
-	// Delete() might be handled in the Expense
-	// Transaction is a joined entity, we don't provide diret read operation
 }

internal/howmuch/usecase/usecase/event.go

@@ -36,8 +36,6 @@ type eventUsecase struct {
 	userUC      User
 	eventRepo   repo.EventRepository
 	expenseRepo repo.ExpenseRepository
-	participationRepo repo.ParticipationRepository
-	transactionRepo   repo.TransactionRepository
 
 	dbRepo repo.DBRepository
 }
@@ -55,11 +53,9 @@ func NewEventUsecase(
 	uuc User,
 	ev repo.EventRepository,
 	ex repo.ExpenseRepository,
-	pa repo.ParticipationRepository, // XXX: Might be handled in event
-	tr repo.TransactionRepository, // XXX: Might be handled in event
 	db repo.DBRepository,
 ) Event {
-	return &eventUsecase{uuc, ev, ex, pa, tr, db}
+	return &eventUsecase{uuc, ev, ex, db}
 }
 
 func (evuc *eventUsecase) CreateEvent(
@@ -133,10 +129,10 @@ func (evuc *eventUsecase) GetEventDetail(
 	userID, eventID int,
 ) (*model.EventInfoResponse, error) {
 	// Check if the user has the right to get this event
-	err := evuc.participationRepo.CheckParticipation(ctx, userID, eventID)
+	// err := evuc.participationRepo.CheckParticipation(ctx, userID, eventID)
-	if err != nil {
+	// if err != nil {
-		return nil, ErrNoParticipation
+	// 	return nil, ErrNoParticipation
-	}
+	// }
 
 	// Get the eventDetail
 	// TODO: This can also be put into the cache