go 编码

文章目录

package main

import (
    "errors"
    "fmt"
    "time"

    "gorm.io/driver/sqlite"
    "gorm.io/gorm"
)

type Code struct {
    ID        string `gorm:"primaryKey"`
    CreatedAt time.Time
    UpdatedAt time.Time
    Batch     string
    Code      int64
}

func main() {
    db, err := gorm.Open(sqlite.Open("test.db"), &gorm.Config{})
    if err != nil {
        panic("failed to connect database")
    }

    // 迁移 schema
    db.AutoMigrate(&Code{})

    fmt.Println(IncAndGet(db, "test", "oo"))
}

func IncAndGet(db *gorm.DB, idType string, batch string) (id int64, err error) {
    code := Code{ID: idType, Batch: batch}
    var result *gorm.DB
    for i := 0; i <= 10; i++ {
        result = db.First(&code)
        if result.Error == nil {
            if batch == code.Batch {
                newCode := code.Code + 1
                result = db.Debug().Model(&code).Where("code = ?", code.Code).Updates(Code{Code: newCode})
                if result.RowsAffected > 0 {
                    return newCode, nil
                } else {
                    continue
                }
            } else {
                var newCode int64
                newCode = 1
                result = db.Debug().Model(&code).Where("code = ? and batch = ?", code.Code, code.Batch).Updates(Code{Code: newCode, Batch: batch})
                if result.RowsAffected > 0 {
                    return newCode, nil
                } else {
                    continue
                }
            }
        }
        if errors.Is(result.Error, gorm.ErrRecordNotFound) {
            code.Code = 1
            result = db.Create(&code)
            if result.Error != nil {
                continue
            }
            return code.Code, nil
        }
    }

    return 0, result.Error
}