REQUEST: Changes to allow testing & mocking

[ghost]

Many of the top structures in pogreb are concrete structs rather than interfaces, making it difficult to mock without effort in the using package. Changing some of these to interfaces would make mocking, and therefore, unit testing, easier.

[akrylysov]

@serussell thanks for your feedback! You can define your own interface in order to mock the DB structure:

type kvStore interface {
    Put(key []byte, value []byte) error
    Get(key []byte) ([]byte, error)
    Close() error
}

func newPogrebDB(path string) (kvStore, error) {
    return pogreb.Open(path, nil)
}

func newMockDB(path string) (kvStore, error) {
    return &mockDB{}
}

func main() {
    db, err := newPogrebDB("test.db")
    db.Put([]byte("testKey"), []byte("testValue"))
}

Keep in mind that pogreb supports pluggable file systems - the FileSystem option (https://godoc.org/github.com/akrylysov/pogreb#Options). The package comes with two implementations:

• the default OS implementation backed by the operating system's file system
• Mem which stores everything in memory - it's perfect for testing

import (
	"github.com/akrylysov/pogreb"
	"github.com/akrylysov/pogreb/fs"
)

func main() {
    db, err := pogreb.Open(path, &pogreb.Options{FileSystem: fs.Mem})
    db.Put([]byte("testKey"), []byte("testValue"))
}