Merge pull request #46 from getAlby/db-model

Db model

controllers/balance.ctrl.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/getAlby/lndhub.go/lib"
 	"github.com/labstack/echo/v4"
-	"github.com/lightningnetwork/lnd/lnrpc"
 )
 
 // BalanceController : BalanceController struct
@@ -16,16 +15,17 @@ type BalanceController struct{}
 func (BalanceController) Balance(c echo.Context) error {
 	ctx := c.(*lib.LndhubContext)
 	c.Logger().Warn(ctx.User.ID)
-	lndClient := *ctx.LndClient
-	getInfo, err := lndClient.GetInfo(context.TODO(), &lnrpc.GetInfoRequest{})
+
+	db := ctx.DB
+
+	balance, err := ctx.User.CurrentBalance(context.TODO(), db)
 	if err != nil {
-		panic(err)
+		return err
 	}
-	c.Logger().Infof("Connected to LND: %s - %s", getInfo.Alias, getInfo.IdentityPubkey)
 
 	return c.JSON(http.StatusOK, echo.Map{
 		"BTC": echo.Map{
-			"AvailableBalance": 1,
+			"AvailableBalance": balance,
 		},
 	})
 }

controllers/create.ctrl.go

@@ -2,6 +2,7 @@ package controllers
 
 import (
 	"context"
+	"database/sql"
 	"math/rand"
 	"net/http"
 
@@ -10,6 +11,7 @@ import (
 	"github.com/getAlby/lndhub.go/lib/security"
 	"github.com/labstack/echo/v4"
 	"github.com/labstack/gommon/random"
+	"github.com/uptrace/bun"
 )
 
 const alphaNumBytes = random.Alphanumeric
@@ -20,6 +22,8 @@ type CreateUserController struct{}
 // CreateUser : Create user Controller
 func (CreateUserController) CreateUser(c echo.Context) error {
 	ctx := c.(*lib.LndhubContext)
+
+	// optional parameters that we currently do not use
 	type RequestBody struct {
 		PartnerID   string `json:"partnerid"`
 		AccountType string `json:"accounttype"`
@@ -34,14 +38,35 @@ func (CreateUserController) CreateUser(c echo.Context) error {
 
 	user := models.User{}
 
+	// generate user login/password (TODO: allow the user to choose a login/password?)
 	user.Login = randStringBytes(8)
 	password := randStringBytes(15)
+	// we only store the hashed password but return the initial plain text password in the HTTP response
 	hashedPassword := security.HashPassword(password)
 	user.Password = hashedPassword
 
-	if _, err := db.NewInsert().Model(&user).Exec(context.TODO()); err != nil {
+	// Create user and the user's accounts
+	// We use double-entry bookkeeping so we use 4 accounts: incoming, current, outgoing and fees
+	// Wrapping this in a transaction in case something fails
+	err := db.RunInTx(context.TODO(), &sql.TxOptions{}, func(ctx context.Context, tx bun.Tx) error {
+		if _, err := tx.NewInsert().Model(&user).Exec(ctx); err != nil {
+			return err
+		}
+		accountTypes := []string{"incoming", "current", "outgoing", "fees"}
+		for _, accountType := range accountTypes {
+			account := models.Account{UserID: user.ID, Type: accountType}
+			if _, err := db.NewInsert().Model(&account).Exec(ctx); err != nil {
+				return err
+			}
+		}
+		return nil
+	})
+
+	// Was the DB transaction successful?
+	if err != nil {
 		return err
 	}
+
 	var ResponseBody struct {
 		Login    string `json:"login"`
 		Password string `json:"password"`

controllers/payinvoice.ctrl.go

@@ -1,8 +1,11 @@
 package controllers
 
 import (
+	"context"
 	"net/http"
 
+	"github.com/getAlby/lndhub.go/db/models"
+	"github.com/getAlby/lndhub.go/lib"
 	"github.com/labstack/echo/v4"
 )
 
@@ -11,9 +14,10 @@ type PayInvoiceController struct{}
 
 // PayInvoice : Pay invoice Controller
 func (PayInvoiceController) PayInvoice(c echo.Context) error {
+	ctx := c.(*lib.LndhubContext)
 	var reqBody struct {
 		Invoice string `json:"invoice" validate:"required"`
-		Amount  int    `json:"amount" validate:"gt=0"`
+		Amount  int    `json:"amount" validate:"omitempty,gte=0"`
 	}
 
 	if err := c.Bind(&reqBody); err != nil {
@@ -28,5 +32,25 @@ func (PayInvoiceController) PayInvoice(c echo.Context) error {
 		})
 	}
 
+	db := ctx.DB
+	debitAccount, err := ctx.User.AccountFor("current", context.TODO(), db)
+	if err != nil {
+		return err
+	}
+	creditAccount, err := ctx.User.AccountFor("outgoing", context.TODO(), db)
+	if err != nil {
+		return err
+	}
+
+	entry := models.TransactionEntry{
+		UserID:          ctx.User.ID,
+		CreditAccountID: creditAccount.ID,
+		DebitAccountID:  debitAccount.ID,
+		Amount:          1000,
+	}
+	if _, err := db.NewInsert().Model(&entry).Exec(context.TODO()); err != nil {
+		return err
+	}
+
 	return nil
 }

db/migrations/20220119021600_balances.up.sql

@@ -0,0 +1,18 @@
+CREATE VIEW account_ledgers(
+	account_id,
+	transaction_entry_id,
+	amount
+) AS
+    SELECT
+		transaction_entries.credit_account_id,
+		transaction_entries.id,
+		transaction_entries.amount
+	FROM
+		transaction_entries
+	UNION ALL
+	SELECT
+		transaction_entries.debit_account_id,
+		transaction_entries.id,
+		(0 - transaction_entries.amount)
+	FROM
+		transaction_entries;

db/migrations/main.go

@@ -8,9 +8,7 @@ import (
 
 var Migrations = migrate.NewMigrations()
 
-// remove the first of 3 slashes to enable sql migrations
-// probably not needed as we are targeting several dialects
-///go:embed *.sql
+//go:embed *.sql
 var sqlMigrations embed.FS
 
 func init() {

db/models/account.go

@@ -2,6 +2,8 @@ package models
 
 // Account : Account Model
 type Account struct {
-	UserID int64
-	Type   string
+	ID     int64  `bun:",pk,autoincrement"`
+	UserID int64  `bun:",notnull"`
+	User   *User  `bun:"rel:belongs-to,join:user_id=id"`
+	Type   string `bun:",notnull"`
 }

db/models/invoice.go

@@ -12,6 +12,7 @@ type Invoice struct {
 	ID                 uint         `json:"id" bun:",pk,autoincrement"`
 	Type               string       `json:"type"`
 	UserID             int64        `json:"user_id"`
+	User               *User        `bun:"rel:belongs-to,join:user_id=id"`
 	TransactionEntryID uint         `json:"transaction_entry_id"`
 	Amount             uint         `json:"amount"`
 	Memo               string       `json:"memo"`

db/models/transactionentries.go

@@ -1,15 +0,0 @@
-package models
-
-import (
-	"time"
-)
-
-// TransactionEntry : Transaction Entries Model
-type TransactionEntry struct {
-	UserID          uint
-	InvoiceID       uint
-	CreditAccountID uint
-	DebitAccountID  uint
-	Amount          uint64
-	CreatedAt       time.Time `bun:",nullzero,notnull,default:current_timestamp"`
-}

db/models/transactionentry.go

@@ -0,0 +1,22 @@
+package models
+
+import (
+	"time"
+)
+
+// TransactionEntry : Transaction Entries Model
+type TransactionEntry struct {
+	ID              int64    `bun:",pk,autoincrement"`
+	UserID          int64    `bun:",notnull"`
+	User            *User    `bun:"rel:belongs-to,join:user_id=id"`
+	InvoiceID       int64    `bun:",notnull"`
+	Invoice         *Invoice `bun:"rel:belongs-to,join:invoice_id=id"`
+	ParentID        int64
+	Parent          *TransactionEntry `bun:"rel:belongs-to"`
+	CreditAccountID int64             `bun:",notnull"`
+	CreditAccount   *Account          `bun:"rel:belongs-to,join:credit_account_id=id"`
+	DebitAccountID  int64             `bun:",notnull"`
+	DebitAccount    *Account          `bun:"rel:belongs-to,join:debit_account_id=id"`
+	Amount          int64             `bun:",notnull"`
+	CreatedAt       time.Time         `bun:",nullzero,notnull,default:current_timestamp"`
+}

db/models/user.go

@@ -16,6 +16,8 @@ type User struct {
 	Password  string         `bun:",notnull"`
 	CreatedAt time.Time      `bun:",nullzero,notnull,default:current_timestamp"`
 	UpdatedAt bun.NullTime
+	Invoices  []*Invoice `bun:"rel:has-many,join:id=user_id"`
+	Accounts  []*Account `bun:"rel:has-many,join:id=user_id"`
 }
 
 func (u *User) BeforeAppendModel(ctx context.Context, query bun.Query) error {
@@ -26,4 +28,21 @@ func (u *User) BeforeAppendModel(ctx context.Context, query bun.Query) error {
 	return nil
 }
 
+func (u *User) AccountFor(accountType string, ctx context.Context, db bun.IDB) (Account, error) {
+	account := Account{}
+	err := db.NewSelect().Model(&account).Where("user_id = ? AND type= ?", u.ID, accountType).Limit(1).Scan(ctx)
+	return account, err
+}
+
+func (u *User) CurrentBalance(ctx context.Context, db bun.IDB) (int64, error) {
+	var balance int64
+
+	account, err := u.AccountFor("current", ctx, db)
+	if err != nil {
+		return balance, err
+	}
+	err = db.NewSelect().Table("account_ledgers").ColumnExpr("sum(account_ledgers.amount) as balance").Where("account_ledgers.account_id = ?", account.ID).Scan(context.TODO(), &balance)
+	return balance, err
+}
+
 var _ bun.BeforeAppendModelHook = (*User)(nil)