/
conn.go
74 lines (65 loc) · 1.38 KB
/
conn.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
package db
import (
"database/sql"
"sync"
"time"
"github.com/jmoiron/sqlx"
)
// Connect ...
func Connect(driver string, datasource string, migrations ...Migration) (*DB, error) {
db, err := sql.Open(driver, datasource)
if err != nil {
return nil, err
}
switch driver {
case "mysql":
db.SetMaxIdleConns(0)
}
if err := pingDatabase(db); err != nil {
return nil, err
}
if err := setupDatabase(db, driver, migrations...); err != nil {
return nil, err
}
var engine Driver
var locker Locker
switch driver {
case "mysql":
engine = MySQL
locker = &nopLocker{}
case "postgres":
engine = Postgres
locker = &nopLocker{}
default:
engine = Sqlite
locker = &sync.RWMutex{}
}
return &DB{
conn: sqlx.NewDb(db, driver),
lock: locker,
driver: engine,
}, nil
}
// helper function to ping the database with backoff to ensure
// a connection can be established before we proceed with the
// database setup and migration.
func pingDatabase(db *sql.DB) (err error) {
for i := 0; i < 30; i++ {
err = db.Ping()
if err == nil {
return
}
time.Sleep(time.Second)
}
return
}
// helper function to setup the databsae by performing automated
// database migration steps.
func setupDatabase(db *sql.DB, driver string, migrations ...Migration) error {
for _, mig := range migrations {
if mig.Driver == driver {
return mig.Migrator.Migrate(db)
}
}
return nil
}