RamSQL has been written to be used in your project's test suite.
Unit testing in Go is simple, create a foo_test.go import testing and run go test ./....
But then there is SQL queries, constraints, CRUD...and suddenly you need a PostgresSQL, setup scripts and nothing is easy anymore.
The idea is to avoid setup, DBMS installation and credentials management as long as possible. A unique engine is tied to a single sql.DB with as much sql.Conn as needed providing a unique DataSourceName. Bottom line : One DataSourceName per test and you have full test isolation in no time.
go get github.com/proullon/ramsql
Let's say you want to test the function LoadUserAddresses :
func LoadUserAddresses(db *sql.DB, userID int64) ([]string, error) {
query := `SELECT address.street_number, address.street FROM address
JOIN user_addresses ON address.id=user_addresses.address_id
WHERE user_addresses.user_id = $1;`
rows, err := db.Query(query, userID)
if err != nil {
return nil, err
}
var addresses []string
for rows.Next() {
var number int
var street string
if err := rows.Scan(&number, &street); err != nil {
return nil, err
}
addresses = append(addresses, fmt.Sprintf("%d %s", number, street))
}
return addresses, nil
}Use RamSQL to test it in a disposable isolated in-memory SQL engine :
package myproject
import (
"database/sql"
"fmt"
"testing"
_ "github.com/proullon/ramsql/driver"
)
func TestLoadUserAddresses(t *testing.T) {
batch := []string{
`CREATE TABLE address (id BIGSERIAL PRIMARY KEY, street TEXT, street_number INT);`,
`CREATE TABLE user_addresses (address_id INT, user_id INT);`,
`INSERT INTO address (street, street_number) VALUES ('rue Victor Hugo', 32);`,
`INSERT INTO address (street, street_number) VALUES ('boulevard de la République', 23);`,
`INSERT INTO address (street, street_number) VALUES ('rue Charles Martel', 5);`,
`INSERT INTO address (street, street_number) VALUES ('chemin du bout du monde ', 323);`,
`INSERT INTO address (street, street_number) VALUES ('boulevard de la liberté', 2);`,
`INSERT INTO address (street, street_number) VALUES ('avenue des champs', 12);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (2, 1);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (4, 1);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (2, 2);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (2, 3);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (4, 4);`,
`INSERT INTO user_addresses (address_id, user_id) VALUES (4, 5);`,
}
db, err := sql.Open("ramsql", "TestLoadUserAddresses")
if err != nil {
t.Fatalf("sql.Open : Error : %s\n", err)
}
defer db.Close()
for _, b := range batch {
_, err = db.Exec(b)
if err != nil {
t.Fatalf("sql.Exec: Error: %s\n", err)
}
}
addresses, err := LoadUserAddresses(db, 1)
if err != nil {
t.Fatalf("Too bad! unexpected error: %s", err)
}
if len(addresses) != 2 {
t.Fatalf("Expected 2 addresses, got %d", len(addresses))
}
}Done. No need for a running PostgreSQL or a setup. Your tests are isolated, and compliant with go tools.
Let's say you have a SQL describing your application structure:
CREATE TABLE IF NOT EXISTS address (id BIGSERIAL PRIMARY KEY, street TEXT, street_number INT);
CREATE TABLE IF NOT EXISTS user_addresses (address_id INT, user_id INT);You may want to test its validity:
$ go install github.com/proullon/ramsql
$ ramsql < schema.sql
ramsql> Query OK. 1 rows affected
ramsql> Query OK. 1 rows affected
$ echo $?
0Find bellow all objectives for v1.0.0
| Name | Category | Parsing | Implementation |
|---|---|---|---|
| Table | SQL | ✔️ | ✔️ |
| Schema | SQL | ✔️ | ✔️ |
| CREATE | SQL | ✔️ | ✔️ |
| PRIMARY_KEY | SQL | ✔️ | ✔️ |
| DEFAULT | SQL | ✔️ | ✔️ |
| INSERT | SQL | ✔️ | ✔️ |
| UNIQUE | SQL | ✔️ | ✔️ |
| FOREIGN KEY | SQL | ✖️ | ✖️ |
| SELECT | SQL | ✔️ | ✔️ |
| backtick | SQL | ✔️ | ✔️ |
| quote | SQL | ✔️ | ✔️ |
| double quote | SQL | ✔️ | ✔️ |
| COUNT | SQL | ✔️ | ✔️ |
| MAX | SQL | ✔️ | ✔️ |
| ORDER BY | SQL | ✔️ | ✔️ |
| UPDATE | SQL | ✔️ | ✔️ |
| DELETE | SQL | ✔️ | ✔️ |
| DROP | SQL | ✔️ | ✔️ |
| INNER JOIN | SQL | ✔️ | ✔️ |
| OUTER JOIN | SQL | ✔️ | ✖️ |
| timestamp | SQL | ✔️ | ✔️ |
| now() | SQL | ✔️ | ✔️ |
| OFFSET | SQL | ✔️ | ✔️ |
| Transactions | SQL | ✔️ | ✔️ |
| BEGIN | SQL | ✖️ | ✖️ |
| COMMIT | SQL | ✖️ | ✖️ |
| Index | SQL | ✔️ | ✔️ |
| Hash index | SQL | ✔️ | ✔️ |
| B-Tree index | SQL | ✔️ | ✖️ |
| JSON | SQL | ✖️ | ✖️ |
| AS | SQL | ✖️ | ✖️ |
| CLI | Testing | ✔️ | ✔️ |
| Breakpoint | Testing | ✖️ | ✖️ |
| Query history | Testing | ✖️ | ✖️ |
| Size limit | Testing | ✖️ | ✖️ |
| Autogeneration | Testing | ✖️ | ✖️ |
| TTL | Caching | ✖️ | ✖️ |
| LFRU | Caching | ✖️ | ✖️ |
| Gorm | Compatibility | ✔️ | ✔️ |
- Full isolation between tests
- No setup (either file or databases)
- Good performance
- Database schema validation
- ALTER file validation
- File system full error with configurable maximum database size
- Random configurable slow queries
- Random connection error
If you intend to use ramsql with the GORM ORM, you should use the GORM Postgres driver. A working example would be:
import (
"database/sql"
"testing"
"gorm.io/driver/postgres"
"gorm.io/gorm"
)
type Product struct {
gorm.Model
Code string
Price uint
TestBigint uint64 `gorm:"test_bigint;type:BIGINT UNSIGNED AUTO_INCREMENT"`
}
// From https://gorm.io/docs/connecting_to_the_database.html
// and https://gorm.io/docs/
func main() {
ramdb, err := sql.Open("ramsql", "TestGormQuickStart")
db, err := gorm.Open(postgres.New(postgres.Config{
Conn: ramdb,
}),
&gorm.Config{})
// Migrate the schema
err = db.AutoMigrate(&Product{})
// Create
err = db.Create(&Product{Code: "D42", Price: 100}).Error
// Read
var product Product
err = db.First(&product, 1).Error // find product with integer primary key
err = db.First(&product, "code = ?", "D42").Error // find product with code D42
err = db.First(&product, "Code = ?", "D42").Error // find product with code D42
// Update - update product's price to 200
err = db.Model(&product).Update("Price", 200).Error
// Update - update multiple fields
err = db.Model(&product).Updates(Product{Price: 200, Code: "F42"}).Error // non-zero fields
err = db.Model(&product).Updates(map[string]interface{}{"Price": 200, "Code": "F42"}).Error
// Delete - delete product
err = db.Delete(&product, 1).Error
_ = err
}What options do we have to store objects:
- unsafe memory paging
- map
- slice
- linked list
The issue with having a lot of objects (rows here) in memory is Garbage Collector pause. The processus will lock objects to determine if there is any pointers to it. This becomes an issue with map[any]*Something since GC will lock the map to check all pointers.
Unsafe memory paging is a bit tricky to keep portable.
Slices are nice, and could grow non linearly capped with available RAM.
The simplest option regarding GC pause and rows storage is linked list. Easy to update and remove rows without overhead, while keeping GC functioning properly.
We want Hash index to fetch rows in O(1) time with = operator. This means we need to use a map, without using pointers. That's where uintptr comes to play. Hash index uses map[string]uintptr or map[int64]uintptr to keep track of pointer to linked list elements, while discarding GC checks.
We also want Binary Tree index to fetch rows in O(log(n)) time with <, <=, >, >= operators.
RamSQL only uses table level lock transactions. In case of error or call to Rollback(), changes will be reverted back into modified relation.
Commit() releases the locks.
agnostic->memstoreexecutor->sql