Files
gonic/db/db.go
2022-04-13 01:10:46 +01:00

140 lines
2.8 KiB
Go

package db
import (
"errors"
"fmt"
"log"
"net/url"
"os"
"strings"
"github.com/jinzhu/gorm"
)
func DefaultOptions() url.Values {
return url.Values{
// with this, multiple connections share a single data and schema cache.
// see https://www.sqlite.org/sharedcache.html
"cache": {"shared"},
// with this, the db sleeps for a little while when locked. can prevent
// a SQLITE_BUSY. see https://www.sqlite.org/c3ref/busy_timeout.html
"_busy_timeout": {"30000"},
"_journal_mode": {"WAL"},
"_foreign_keys": {"true"},
}
}
func mockOptions() url.Values {
return url.Values{
"_foreign_keys": {"true"},
}
}
type DB struct {
*gorm.DB
}
func New(path string, options url.Values) (*DB, error) {
// https://github.com/mattn/go-sqlite3#connection-string
url := url.URL{
Scheme: "file",
Opaque: path,
}
url.RawQuery = options.Encode()
db, err := gorm.Open("sqlite3", url.String())
if err != nil {
return nil, fmt.Errorf("with gorm: %w", err)
}
db.SetLogger(log.New(os.Stdout, "gorm ", 0))
db.DB().SetMaxOpenConns(1)
return &DB{DB: db}, nil
}
func NewMock() (*DB, error) {
return New(":memory:", mockOptions())
}
func (db *DB) GetSetting(key string) (string, error) {
setting := &Setting{}
if err := db.Where("key=?", key).First(setting).Error; err != nil && !errors.Is(err, gorm.ErrRecordNotFound) {
return "", err
}
return setting.Value, nil
}
func (db *DB) SetSetting(key, value string) error {
return db.
Where(Setting{Key: key}).
Assign(Setting{Value: value}).
FirstOrCreate(&Setting{}).
Error
}
func (db *DB) InsertBulkLeftMany(table string, head []string, left int, col []int) error {
if len(col) == 0 {
return nil
}
var rows []string
var values []interface{}
for _, c := range col {
rows = append(rows, "(?, ?)")
values = append(values, left, c)
}
q := fmt.Sprintf("INSERT OR IGNORE INTO %q (%s) VALUES %s",
table,
strings.Join(head, ", "),
strings.Join(rows, ", "),
)
return db.Exec(q, values...).Error
}
func (db *DB) GetUserByID(id int) *User {
user := &User{}
err := db.
Where("id=?", id).
First(user).
Error
if errors.Is(err, gorm.ErrRecordNotFound) {
return nil
}
return user
}
func (db *DB) GetUserByName(name string) *User {
user := &User{}
err := db.
Where("name=?", name).
First(user).
Error
if errors.Is(err, gorm.ErrRecordNotFound) {
return nil
}
return user
}
func (db *DB) Begin() *DB {
return &DB{DB: db.DB.Begin()}
}
type ChunkFunc func(*gorm.DB, []int64) error
func (db *DB) TransactionChunked(data []int64, cb ChunkFunc) error {
if len(data) == 0 {
return nil
}
// https://sqlite.org/limits.html
const size = 999
return db.Transaction(func(tx *gorm.DB) error {
for i := 0; i < len(data); i += size {
end := i + size
if end > len(data) {
end = len(data)
}
if err := cb(tx, data[i:end]); err != nil {
return err
}
}
return nil
})
}