Documentation
¶
Overview ¶
Package encoding provides marshalling values to and from SQL. Gracefully handles null values.
The simplest way to use this is to take advantage of the base marshal and unmarshal functions:
An example below:
db, err := sql.Open("sqlite3", ":memory:")
type user struct {
ID int `db:"id"`
}
cols, vals, err := encoding.Marshal(user{1})
_, err = db.Exec(
"insert into users ("+strings.Join(cols, ",")+") values "+"(?)", vals...,
)
users := []user{}
rows, err := db.Query("select * from users")
err = encoding.Unmarshal(&users, rows)
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
var ( // ErrRequiresPtr is returned if a non pointer value is passed to Decode. ErrRequiresPtr = errors.New("sqlkit/encoding: non pointer passed to Decode") // ErrMustNotBeNil is returned if a nil value is passed to Decode. ErrMustNotBeNil = errors.New("sqlkit/encoding: nil value passed to Decode") // ErrMissingDestination is returned if a destination value is missing and // unsafe is not configured. ErrMissingDestination = errors.New("sqlkit/encoding: missing destination") // ErrTooManyColumns is returned when too many columns are present to scan // into a value. ErrTooManyColumns = errors.New("sqlkit/encoding: too many columns to scan") // ErrNoRows is mirrored from the database/sql package. ErrNoRows = sql.ErrNoRows )
var DefaultMapper = reflectx.NewMapperFunc("db", Underscore)
DefaultMapper is the default reflectx mapper used. This uses strings.ToLower to map field names.
var ( // ErrDuplicateValue is returned when duplicate values exist in the struct. ErrDuplicateValue = errors.New("sqlkit/marshal: duplicate values") )
Functions ¶
func Marshal ¶
Marshal runs the default encoder.
Example ¶
package main
import (
"database/sql"
"fmt"
"strings"
"github.com/colinjfw/sqlkit/encoding"
)
func main() {
db, err := sql.Open("sqlite3", ":memory:")
if err != nil {
panic(err)
}
type user struct {
ID int `db:"id"`
}
_, err = db.Exec("create table users (id int primary key)")
if err != nil {
panic(err)
}
usr := user{ID: 1}
cols, vals, err := encoding.Marshal(usr)
if err != nil {
panic(err)
}
fmt.Printf("cols: %v, vals: %v\n", cols, vals)
_, err = db.Exec(
"insert into users ("+strings.Join(cols, ",")+") values "+"(?)", vals...,
)
if err != nil {
panic(err)
}
}
Output: cols: [id], vals: [1]
func Underscore ¶
Underscore will map camel case wording to snake case.
func Unmarshal ¶
Unmarshal will run Decode with the default Decoder configuration.
Example ¶
package main
import (
"database/sql"
"fmt"
"strings"
"github.com/colinjfw/sqlkit/encoding"
)
func main() {
db, err := sql.Open("sqlite3", ":memory:")
if err != nil {
panic(err)
}
type user struct {
ID int `db:"id"`
}
_, err = db.Exec("create table users (id int primary key)")
if err != nil {
panic(err)
}
usr := user{ID: 1}
cols, vals, err := encoding.Marshal(usr)
if err != nil {
panic(err)
}
fmt.Printf("cols: %v, vals: %v\n", cols, vals)
_, err = db.Exec(
"insert into users ("+strings.Join(cols, ",")+") values "+"(?)", vals...,
)
if err != nil {
panic(err)
}
rows, err := db.Query("select * from users")
if err != nil {
panic(err)
}
usrs := []user{}
err = encoding.Unmarshal(&usrs, rows)
if err != nil {
panic(err)
}
fmt.Printf("query: %+v\n", usrs)
}
Output: cols: [id], vals: [1] query: [{ID:1}]
Types ¶
type Encoder ¶
type Encoder struct {
// contains filtered or unexported fields
}
Encoder manages options for encoding.
func NewEncoder ¶
func NewEncoder() Encoder
NewEncoder returns an Encoder with the default settings which are blank.
func (Encoder) Decode ¶
Decode does the work of decoding an *sql.Rows into a struct, array or scalar value. Depending on the value passed in the decoder will perform the following actions:
- If an array is passed in the decoder will work through all rows initializing and scanning in a new instance of the value(s) for all rows.
- If the values inside the array are scalar, then the decoder will check for only a single column to scan and scan this in.
- If a single struct or scalar is passed in the decoder will loop once over the rows returning sql.ErrNoRows if this is possible and scan the value.
The rows object is not closed after iteration is completed. The Decode function is thread safe.
func (Encoder) Encode ¶
Encode will encode to a set of fields and values using the Encoder's settings. It will return and error if there are duplicate fields and unsafe is not set.
Source Files