From 7b75dde2664436555b53f6f15be93dacd8aef59c Mon Sep 17 00:00:00 2001
From: Bill Tanthowi Jauhari <bill.tanthowi@majoo.id>
Date: Mon, 24 Aug 2020 19:44:34 +0700
Subject: [PATCH] extract query builder for bulk insert

---
 main.go              | 14 +++++++--
 models/user_model.go |  8 ++---
 utils/agregator.go   | 32 +++++++++++++++++++
 utils/collector.go   | 74 ++++++++++++++++++++++++++++++++++++++++++++
 utils/helper.go      | 48 ----------------------------
 5 files changed, 122 insertions(+), 54 deletions(-)
 create mode 100644 utils/agregator.go
 create mode 100644 utils/collector.go
 delete mode 100644 utils/helper.go

diff --git a/main.go b/main.go
index 188fd5d..5266b55 100644
--- a/main.go
+++ b/main.go
@@ -1,12 +1,22 @@
 package main
 
 import (
+	"fmt"
 	"go-bulk-insert/models"
 	"go-bulk-insert/utils"
 )
 
 func main() {
 	var user models.UserModel
-	var exceptField = []string{"fullname"}
-	utils.ExtractModelField(user, exceptField)
+	bulk := new(utils.BulkInsertStruct)
+
+	value := [][]interface{}{
+		{"bill", 12, "23-10-1994", "082245088948"},
+		{"bill", 12, "23-10-1994", "082245088948"},
+		{"bill", 12, "23-10-1994", "082245088948"},
+	}
+	fmt.Println(bulk.ArrangeValue(value).
+		ExtractModelField(user, []string{}).
+		PutQueryTogether("users").
+		GetQuery())
 }
diff --git a/models/user_model.go b/models/user_model.go
index 2f99097..825ed1f 100644
--- a/models/user_model.go
+++ b/models/user_model.go
@@ -1,8 +1,8 @@
 package models
 
 type UserModel struct {
-	FullName  string `json:"fullname"`
-	Age       uint16 `json:"age"`
-	BirthDate string `json:"birthdate"`
-	MSISDN    string `json:"msisdn"`
+	FullName  string `json:"fullname" gorm:"column:fullname"`
+	Age       uint16 `json:"age" gorm:"column:age"`
+	BirthDate string `json:"birthdate" gorm:"column:birthdate"`
+	MSISDN    string `json:"msisdn" gorm:"column:msisdn"`
 }
diff --git a/utils/agregator.go b/utils/agregator.go
new file mode 100644
index 0000000..30e550d
--- /dev/null
+++ b/utils/agregator.go
@@ -0,0 +1,32 @@
+package utils
+
+func (s *BulkInsertStruct) Test() (i *BulkInsertStruct) {
+	return
+}
+
+func (t *BulkInsertStruct) SetColumn(columns string) (s *BulkInsertStruct) {
+	t.Columns = &columns
+	return t
+}
+
+func (t *BulkInsertStruct) SetValues(values string) (s *BulkInsertStruct) {
+	t.Values = &values
+	return t
+}
+
+func (t *BulkInsertStruct) SetQuery(query string) (s *BulkInsertStruct) {
+	t.Query = &query
+	return t
+}
+
+func (t *BulkInsertStruct) GetColumn() string {
+	return *t.Columns
+}
+
+func (t *BulkInsertStruct) GetValues() string {
+	return *t.Values
+}
+
+func (t *BulkInsertStruct) GetQuery() string {
+	return *t.Query
+}
diff --git a/utils/collector.go b/utils/collector.go
new file mode 100644
index 0000000..afd6b7b
--- /dev/null
+++ b/utils/collector.go
@@ -0,0 +1,74 @@
+package utils
+
+import (
+	"fmt"
+	"reflect"
+)
+
+type BulkInsertStruct struct {
+	Columns *string
+	Query   *string
+	Values  *string
+}
+
+func (t *BulkInsertStruct) ExtractModelField(model interface{}, exceptionalField []string) (s *BulkInsertStruct) {
+	var reflectValue = reflect.ValueOf(model)
+	var columns string
+
+	if reflectValue.Kind() == reflect.Ptr {
+		reflectValue = reflectValue.Elem()
+	}
+
+	var reflectType = reflectValue.Type()
+
+	for i := 0; i < reflectValue.NumField(); i++ {
+		current_field := reflectType.Field(i).Tag.Get("json")
+		if len(exceptionalField) > 0 {
+			for _, item := range exceptionalField {
+				if current_field != item {
+					if (i + 1) < reflectValue.NumField() {
+						columns += fmt.Sprintf("'%v', ", current_field)
+					} else {
+						columns += fmt.Sprintf("'%v'", current_field)
+					}
+				}
+			}
+		} else {
+			if (i + 1) < reflectValue.NumField() {
+				columns += fmt.Sprintf("'%v', ", current_field)
+			} else {
+				columns += fmt.Sprintf("'%v'", current_field)
+			}
+		}
+
+	}
+	t.SetColumn(columns)
+	return t
+}
+
+func (t *BulkInsertStruct) ArrangeValue(models [][]interface{}) (s *BulkInsertStruct) {
+	var values string
+	for indexCols, cols := range models {
+		var valueRows string
+		for indexRows, rows := range cols {
+			if (indexRows + 1) < len(cols) {
+				valueRows += fmt.Sprintf("'%v', ", rows)
+			} else {
+				valueRows += fmt.Sprintf("'%v'", rows)
+			}
+		}
+
+		if (indexCols + 1) < len(models) {
+			values += fmt.Sprintf("(%v),", valueRows)
+		} else {
+			values += fmt.Sprintf("(%v);", valueRows)
+		}
+	}
+	t.SetValues(values)
+	return t
+}
+
+func (t *BulkInsertStruct) PutQueryTogether(tableName string) (s *BulkInsertStruct) {
+	t.SetQuery(fmt.Sprintf("INSERT INTO %v (%v) VALUES %v", tableName, t.GetColumn(), t.GetValues()))
+	return t
+}
diff --git a/utils/helper.go b/utils/helper.go
deleted file mode 100644
index da50d43..0000000
--- a/utils/helper.go
+++ /dev/null
@@ -1,48 +0,0 @@
-package utils
-
-import (
-	"fmt"
-	"reflect"
-)
-
-func ExtractModelField(model interface{}, exceptionalField []string) {
-	var reflectValue = reflect.ValueOf(model)
-
-	if reflectValue.Kind() == reflect.Ptr {
-		reflectValue = reflectValue.Elem()
-	}
-
-	var reflectType = reflectValue.Type()
-
-	for i := 0; i < reflectValue.NumField(); i++ {
-		for _, item := range exceptionalField {
-			current_field := reflectType.Field(i).Tag.Get("json")
-			if current_field != item {
-				fmt.Println(current_field)
-			}
-		}
-	}
-}
-
-func PutAllValueTogether(models [][]interface{}) string {
-	var values string
-
-	for indexCols, cols := range models {
-		var valueRows string
-		for indexRows, rows := range cols {
-			if (indexRows + 1) < len(cols) {
-				valueRows += fmt.Sprintf("'%v', ", rows.(string))
-			} else {
-				valueRows += fmt.Sprintf("'%v' ", rows.(string))
-			}
-		}
-
-		if (indexCols + 1) < len(cols) {
-			values += fmt.Sprintf("(%v),", valueRows)
-		} else {
-			values += fmt.Sprintf("(%v);", valueRows)
-		}
-	}
-
-	return values
-}