README
¶
db
mysql 基础库，开放有限接口，支持日志、opentracing 和 prometheus 监控。
配置
DB 配置，格式为 DB_${NAME}_DSN，内容参考 https://github.com/go-sql-driver/mysql#dsn-data-source-name
必须设置 parseTime 选项。设置好了就可以通过 ${NAME} 获取 DB 连接池。
时区问题参考 https://www.jianshu.com/p/3f7fc9093db4
示例
import "context"
import "github.com/learninto/goutil/db"
ctx := context.Background()
c := db.Get(ctx, "default")
sql := "insert into foo(id) values(1)"
q := SQLUpdate("foo", sql)
result, err := c.ExecContext(ctx, q)
// 执行 db 事务
err := c.ExecTx(ctx, func(ctx context.Context, tx db.Conn) error {
sql := "insert into foo(id) values(1)"
q := SQLUpdate("foo", sql)
result, err := c.ExecContext(ctx, q)
if err != nil {
return err
}
sql := "insert into foo(id) values(2)"
q := SQLUpdate("foo", sql)
result, err = tx.ExecContext(ctx, q)
if err != nil {
return err
}
return nil
})
Documentation
¶
Overview ¶
Package db 提供 mysql 封装
Index ¶
- Constants
- func IsDuplicateEntryErr(err error) bool
- func IsNoRowsErr(err error) bool
- func NotFound(err error) bool
- func Reset()
- func ScanAll(dst interface{}, rows Rows) error
- func ScanOne(dst interface{}, rows Rows) error
- func ScanRow(dst interface{}, rows Rows) error
- type C
- type Conn
- type DB
- func (db *DB) ExecContext(ctx context.Context, query Query, args ...interface{}) (sql.Result, error)
- func (db *DB) ExecTx(ctx context.Context, f TxFunc) error
- func (db *DB) QueryContext(ctx context.Context, query Query, args ...interface{}) (*sql.Rows, error)
- func (db *DB) QueryRowContext(ctx context.Context, query Query, args ...interface{}) *sql.Row
- type F
- type Q
- type Query
- type Row
- type RowScanner
- type Rows
- type Tx
- type TxFunc
- type U
Constants ¶
const FieldLogicEgt = 201
FieldLogicEgt 过滤逻辑 201：>=
const FieldLogicElt = 301
FieldLogicElt 过滤逻辑 301: <=；
const FieldLogicEq = 100
FieldLogicEq 过滤逻辑 100：= ；
const FieldLogicGt = 200
FieldLogicGt 过滤逻辑 200：>;
const FieldLogicIn = 500
FieldLogicIn 过滤逻辑 500： in
const FieldLogicLeftLike = 1
FieldLogicLeftLike 过滤逻辑 1：左 like；
const FieldLogicLike = 0
FieldLogicLike 过滤逻辑 0：like ；
const FieldLogicLt = 300
FieldLogicLt 过滤逻辑 300 <；
const FieldLogicNeq = 400
FieldLogicNeq 过滤逻辑 400： <>；
const FieldLogicNotIn = 501
FieldLogicNotIn 过滤逻辑 500： not in
const FieldLogicRightLike = 2
FieldLogicRightLike 过滤逻辑 2：右 like；
const FieldTypeDate = 100
FieldTypeDate 日期
const FieldTypeDateTime = 101
FieldTypeDateTime 日期时间
const FieldTypeInteger = 201
FieldTypeInteger 整数
const FieldTypeListMultiple = 401
FieldTypeListMultiple 列表（可多选）
const FieldTypeListOne = 400
FieldTypeListOne 列表（只能单选）
const FieldTypePositiveInteger = 200
FieldTypePositiveInteger 正整数（包含0）
const FieldTypePositiveRealNumber = 200
FieldTypePositiveRealNumber 正实数（包含0）
const FieldTypeRealNumber = 301
FieldTypeRealNumber 实数
const FieldTypeText = 0
FieldTypeText 文本
const IsMultipleFalse = 0
IsMultipleFalse 是否多重应用条件。是指在sql中，该过滤值在多个子查询中需要用到。 0：否；100：是
const IsMultipleTrue = 100
IsMultipleTrue 是否多重应用条件。是指在sql中，该过滤值在多个子查询中需要用到。 0：否；100：是
Variables ¶
This section is empty.
Functions ¶
func IsDuplicateEntryErr ¶
IsDuplicateEntryErr 判断是否为唯一键冲突错误
func NotFound ¶ added in v1.2.6
NotFound returns true if err is a not found error. This error is returned by ScanOne if there were no rows.
func Reset ¶
func Reset()
Reset 关闭所有 DB 连接 新调用 Get 方法时会使用最新 DB 配置创建连接
如果在配置中开启 HOT_LOAD_DB 开关，则每次下发配置都会重置 DB 连接！
func ScanAll ¶ added in v1.2.6
ScanAll iterates all rows to the end. After iterating it closes the rows, and propagates any errors that could pop up. It expects that destination should be a slice. For each row it scans data and appends it to the destination slice. ScanAll supports both types of slices: slice of structs by a pointer and slice of structs by value, for example:
type User struct {
ID string
Name string
Email string
Age int
}
var usersByPtr []*User
var usersByValue []User
Both usersByPtr and usersByValue are valid destinations for ScanAll function.
Before starting, ScanAll resets the destination slice, so if it's not empty it will overwrite all existing elements.
func ScanOne ¶ added in v1.2.6
ScanOne iterates all rows to the end and makes sure that there was exactly one row otherwise it returns an error. Use NotFound function to check if there were no rows. After iterating ScanOne closes the rows, and propagates any errors that could pop up. It scans data from that single row into the destination.
func ScanRow ¶ added in v1.2.6
ScanRow creates a new RowScanner and calls RowScanner.Scan that scans current row data into the destination. It's just a helper function if you don't bother with efficiency and don't want to instantiate a new RowScanner before iterating the rows, so it could cache the reflection work between Scan calls. See RowScanner for details.
Types ¶
type C ¶
type C struct {
TableName string `json:"-"`
Data string `json:"data"`
OnDuplicateKeyUpdate []string `json:"on_duplicate_key_update"`
}
U 更新
type Conn ¶
type Conn interface {
ExecContext(ctx context.Context, query Query, args ...interface{}) (sql.Result, error)
QueryContext(ctx context.Context, query Query, args ...interface{}) (*sql.Rows, error)
QueryRowContext(ctx context.Context, query Query, args ...interface{}) *sql.Row
}
Conn 简单 DB 接口。用于统一非事务和事务业务逻辑
type DB ¶
type DB struct {
// contains filtered or unexported fields
}
DB 对象，有限开放 sql.DB 功能，支持上报 metrics
func Get ¶
Get 根据配置名字创建并返回 DB 连接池对象
DB 配置名字格式为 DB_{$name}_DSN DB 配置内容格式请参考 https://github.com/go-sql-driver/mysql#dsn-data-source-name Get 是并发安全的，可以在多协程下使用
func (*DB) ExecContext ¶
func (db *DB) ExecContext(ctx context.Context, query Query, args ...interface{}) (sql.Result, error)
ExecContext 执行查询，无返回数据
func (*DB) ExecTx ¶
ExecTx 执行一次事务，回调函数返回 err 或者 panic 或者 ctx 取消都会回滚事务。 返回的 err 为 Commit 或者 Rollback 的错误
type F ¶
type F struct {
// Comment: 字段名称。 用于后端 构造sql。 如果是多重应用条件，则成为占位名称标识
FieldName string `json:"field_name"`
// Comment: 字段类型。 用于前端 不同输入控件，以及限制输入的内容。 0：文本；100： 日期 101：日期时间；200：正整数（包含0）；201：整数；300：正实数（包含0）；301：实数； 400：列表（只能单选）；401：列表（可多选）
FieldType int64 `json:"field_type"`
// Comment: 过滤逻辑。 用于前端：显示查询条件逻辑； 用于后端 构造sql。 0：like ；1：左 like；2：右 like；100：= ；200：>; 201：>= 300 <；301: <=； 400： <>；500： in
FieldLogic int64 `json:"field_logic"`
// Comment: 是否多重应用条件。是指在sql中，该过滤值在多个子查询中需要用到。 0：否；100：是
// Default: 0
IsMultiple int64 `json:"is_multiple"`
// Comment：值
Value string `json:"value"`
}
F 筛选条件
type Q ¶
type Q struct {
Sql string `json:"sql"`
Filters []F `json:"filters"`
ReplaceOrderBy string `json:"replace_order_by"`
ReplaceGroupBy string `json:"replace_group_by"`
CurrentPage int64 `json:"current_page"`
PageSize int64 `json:"page_size"`
}
Q 查询
func (Q) BuildFilter ¶ added in v1.2.7
BuildFilter 获取追加的筛选条件
type RowScanner ¶ added in v1.2.6
type RowScanner struct {
// contains filtered or unexported fields
}
RowScanner embraces Rows and exposes the Scan method that allows scanning data from the current row into the destination. The first time the Scan method is called it parses the destination type via reflection and caches all required information for further scans. Due to this caching mechanism, it's not allowed to call Scan for destinations of different types, the behavior is unknown in that case. RowScanner doesn't proceed to the next row nor close them, it should be done by the client code.
The main benefit of using this type directly is that you can instantiate a RowScanner and manually iterate over the rows and control how data is scanned from each row. This can be beneficial if the result set is large and you don't want to allocate a slice for all rows at once as it would be done in ScanAll.
ScanOne and ScanAll both use RowScanner type internally.
func NewRowScanner ¶ added in v1.2.6
func NewRowScanner(rows Rows) *RowScanner
NewRowScanner returns a new instance of the RowScanner.
func (*RowScanner) Scan ¶ added in v1.2.6
func (rs *RowScanner) Scan(dst interface{}) error
Scan scans data from the current row into the destination. On the first call it caches expensive reflection work and uses it the future calls. See RowScanner for details.
type Rows ¶ added in v1.2.6
type Rows interface {
Close() error
Err() error
Next() bool
Columns() ([]string, error)
Scan(dest ...interface{}) error
}
Rows is an abstract database rows that dbscan can iterate over and get the data from. This interface is used to decouple from any particular database library.
type Tx ¶
type Tx struct {
// contains filtered or unexported fields
}
Tx 事务对象简单封装
func (*Tx) ExecContext ¶
func (tx *Tx) ExecContext(ctx context.Context, query Query, args ...interface{}) (sql.Result, error)
ExecContext 执行写查询 不鼓励在事务中使用读查询，所以只提供 ExecContext 方法 框架会根据返回错误自动提交或者回滚，所以不提供相应方法
Source Files