From b38a83ff363acb26c933e24ac62f9e13ad247f0d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Vin=C3=ADcius=20Garcia?= <vingarcia00@gmail.com>
Date: Thu, 4 Mar 2021 22:58:27 -0300
Subject: [PATCH] Improve the signature of the New() function so it`s more
 readable

---
 benchmark_test.go     | 10 +++++++--
 examples/crud/crud.go |  5 ++++-
 kiss_orm.go           | 47 ++++++++++++++++++++++++++++++++++---------
 kiss_orm_test.go      |  5 ++++-
 4 files changed, 54 insertions(+), 13 deletions(-)

diff --git a/benchmark_test.go b/benchmark_test.go
index 3ce4f42..ffa66e3 100644
--- a/benchmark_test.go
+++ b/benchmark_test.go
@@ -18,7 +18,10 @@ func BenchmarkInsert(b *testing.B) {
 	driver := "postgres"
 	connStr := "host=localhost port=5432 user=postgres password=postgres dbname=kissorm sslmode=disable"
 
-	kissormDB, err := kissorm.New(driver, connStr, 1, "users")
+	kissormDB, err := kissorm.New(driver, connStr, kissorm.Config{
+		MaxOpenConns: 1,
+		TableName:    "users",
+	})
 	if err != nil {
 		b.FailNow()
 	}
@@ -87,7 +90,10 @@ func BenchmarkQuery(b *testing.B) {
 	driver := "postgres"
 	connStr := "host=localhost port=5432 user=postgres password=postgres dbname=kissorm sslmode=disable"
 
-	kissormDB, err := kissorm.New(driver, connStr, 1, "users")
+	kissormDB, err := kissorm.New(driver, connStr, kissorm.Config{
+		MaxOpenConns: 1,
+		TableName:    "users",
+	})
 	if err != nil {
 		b.FailNow()
 	}
diff --git a/examples/crud/crud.go b/examples/crud/crud.go
index 9cec059..0eb740f 100644
--- a/examples/crud/crud.go
+++ b/examples/crud/crud.go
@@ -35,7 +35,10 @@ type Address struct {
 
 func main() {
 	ctx := context.Background()
-	db, err := kissorm.New("sqlite3", "/tmp/hello.sqlite", 1, "users")
+	db, err := kissorm.New("sqlite3", "/tmp/hello.sqlite", kissorm.Config{
+		MaxOpenConns: 1,
+		TableName:    "users",
+	})
 	if err != nil {
 		panic(err.Error())
 	}
diff --git a/kiss_orm.go b/kiss_orm.go
index 678e1fc..27b66b4 100644
--- a/kiss_orm.go
+++ b/kiss_orm.go
@@ -40,13 +40,26 @@ const (
 	insertWithNoIDRetrieval
 )
 
+// Config describes the optional arguments accepted
+// by the kissorm.New() function.
+type Config struct {
+	// MaxOpenCons defaults to 1 if not set
+	MaxOpenConns int
+
+	// TableName must be set in order to use the Insert, Delete and Update helper
+	// functions. If you only intend to make queries or to use the Exec function
+	// it is safe to leave this field unset.
+	TableName string
+
+	// IDColumns defaults to []string{"id"} if unset
+	IDColumns []string
+}
+
 // New instantiates a new Kissorm client
 func New(
 	dbDriver string,
 	connectionString string,
-	maxOpenConns int,
-	tableName string,
-	idCols ...string,
+	config Config,
 ) (DB, error) {
 	db, err := sql.Open(dbDriver, connectionString)
 	if err != nil {
@@ -56,22 +69,26 @@ func New(
 		return DB{}, err
 	}
 
-	db.SetMaxOpenConns(maxOpenConns)
+	if config.MaxOpenConns == 0 {
+		config.MaxOpenConns = 1
+	}
+
+	db.SetMaxOpenConns(config.MaxOpenConns)
 
 	dialect := getDriverDialect(dbDriver)
 	if dialect == nil {
 		return DB{}, fmt.Errorf("unsupported driver `%s`", dbDriver)
 	}
 
-	if len(idCols) == 0 {
-		idCols = append(idCols, "id")
+	if len(config.IDColumns) == 0 {
+		config.IDColumns = []string{"id"}
 	}
 
 	var insertMethod insertMethod
 	switch dbDriver {
 	case "sqlite3":
 		insertMethod = insertWithLastInsertID
-		if len(idCols) > 1 {
+		if len(config.IDColumns) > 1 {
 			insertMethod = insertWithNoIDRetrieval
 		}
 	case "postgres":
@@ -84,9 +101,9 @@ func New(
 		dialect:   dialect,
 		driver:    dbDriver,
 		db:        db,
-		tableName: tableName,
+		tableName: config.TableName,
 
-		idCols:       idCols,
+		idCols:       config.IDColumns,
 		insertMethod: insertMethod,
 	}, nil
 }
@@ -315,6 +332,10 @@ func (c DB) Insert(
 	ctx context.Context,
 	records ...interface{},
 ) error {
+	if c.tableName == "" {
+		return fmt.Errorf("the optional TableName argument was not provided to New(), can't use the Insert method")
+	}
+
 	for _, record := range records {
 		query, params, err := buildInsertQuery(c.dialect, c.tableName, record, c.idCols...)
 		if err != nil {
@@ -460,6 +481,10 @@ func (c DB) Delete(
 	ctx context.Context,
 	ids ...interface{},
 ) error {
+	if c.tableName == "" {
+		return fmt.Errorf("the optional TableName argument was not provided to New(), can't use the Delete method")
+	}
+
 	if len(ids) == 0 {
 		return nil
 	}
@@ -528,6 +553,10 @@ func (c DB) Update(
 	ctx context.Context,
 	records ...interface{},
 ) error {
+	if c.tableName == "" {
+		return fmt.Errorf("the optional TableName argument was not provided to New(), can't use the Update method")
+	}
+
 	for _, record := range records {
 		query, params, err := buildUpdateQuery(c.dialect, c.tableName, record, c.idCols...)
 		if err != nil {
diff --git a/kiss_orm_test.go b/kiss_orm_test.go
index 1aaf31e..570085a 100644
--- a/kiss_orm_test.go
+++ b/kiss_orm_test.go
@@ -373,7 +373,10 @@ func TestInsert(t *testing.T) {
 
 					ctx := context.Background()
 					// Using columns "id" and "name" as IDs:
-					c, err := New(driver, connectionString[driver], 1, "users", "id", "name")
+					c, err := New(driver, connectionString[driver], Config{
+						TableName: "users",
+						IDColumns: []string{"id", "name"},
+					})
 					assert.Equal(t, nil, err)
 
 					u := User{