github.com/rafaeljusto/redigomock

redigomock

Easy way to unit test projects using redigo library (Redis client in go). You can find the latest release here.

install

go get -u github.com/rafaeljusto/redigomock

usage

Here is an example of using redigomock, for more information please check the API documentation.

package main

import (
	"fmt"
	"github.com/gomodule/redigo/redis"
	"github.com/rafaeljusto/redigomock"
)

type Person struct {
	Name string `redis:"name"`
	Age  int    `redis:"age"`
}

func RetrievePerson(conn redis.Conn, id string) (Person, error) {
	var person Person

	values, err := redis.Values(conn.Do("HGETALL", fmt.Sprintf("person:%s", id)))
	if err != nil {
		return person, err
	}

	err = redis.ScanStruct(values, &person)
	return person, err
}

func main() {
	// Simulate command result

	conn := redigomock.NewConn()
	cmd := conn.Command("HGETALL", "person:1").ExpectMap(map[string]string{
		"name": "Mr. Johson",
		"age":  "42",
	})

	person, err := RetrievePerson(conn, "1")
	if err != nil {
		fmt.Println(err)
		return
	}

	if conn.Stats(cmd) != 1 {
		fmt.Println("Command was not used")
		return
	}

	if person.Name != "Mr. Johson" {
		fmt.Printf("Invalid name. Expected 'Mr. Johson' and got '%s'\n", person.Name)
		return
	}

	if person.Age != 42 {
		fmt.Printf("Invalid age. Expected '42' and got '%d'\n", person.Age)
		return
	}

	// Simulate command error

	conn.Clear()
	cmd = conn.Command("HGETALL", "person:1").ExpectError(fmt.Errorf("Simulate error!"))

	person, err = RetrievePerson(conn, "1")
	if err == nil {
		fmt.Println("Should return an error!")
		return
	}

	if conn.Stats(cmd) != 1 {
		fmt.Println("Command was not used")
		return
	}

	fmt.Println("Success!")
}

mocking a subscription

package main

import "github.com/rafaeljusto/redigomock"

func CreateSubscriptionMessage(data []byte) []interface{} {
	values := []interface{}{}
	values = append(values, interface{}([]byte("message")))
	values = append(values, interface{}([]byte("chanName")))
	values = append(values, interface{}(data))
	return values
}

func main() {
	conn := redigomock.NewConn()

	// Setup the initial subscription message
	values := []interface{}{}
	values = append(values, interface{}([]byte("subscribe")))
	values = append(values, interface{}([]byte("chanName")))
	values = append(values, interface{}([]byte("1")))

	conn.Command("SUBSCRIBE", subKey).Expect(values)
	conn.ReceiveWait = true

	// Add a response that will come back as a subscription message
	conn.AddSubscriptionMessage(CreateSubscriptionMessage([]byte("hello")))

	// You need to send messages to conn.ReceiveNow in order to get a response.
	// Sending to this channel will block until receive, so do it in a goroutine
	go func() {
		conn.ReceiveNow <- true // This unlocks the subscribe message
		conn.ReceiveNow <- true // This sends the "hello" message
	}()
}

connections pool

// Note you cannot get access to the connection via the pool,
// the only way is to use this conn variable.
conn := redigomock.NewConn()
pool := &redis.Pool{
	// Return the same connection mock for each Get() call.
	Dial:    func() (redis.Conn, error) { return conn, nil },
	MaxIdle: 10,
}

dynamic handling arguments

Sometimes you need to check the executed arguments in your Redis command. For that you can use the command handler.

package main

import (
	"fmt"
	"github.com/gomodule/redigo/redis"
	"github.com/rafaeljusto/redigomock"
)

func Publish(conn redis.Conn, x, y int) error {
	if x < 0 {
		x = 0
	}
	if y < 0 {
		y = 0
	}
	_, err := conn.Do("PUBLISH", "sumCh", int64(x+y))
	return err
}

func main() {
	conn := redigomock.NewConn()
	conn.GenericCommand("PUBLISH").Handle(redigomock.ResponseHandler(func(args []interface{}) (interface{}, error) {{
		if len(args) != 2 {
			return nil, fmt.Errorf("unexpected number of arguments: %d", len(args))
		}
		v, ok := args[1].(int64)
		if !ok {
			return nil, fmt.Errorf("unexpected type %T", args[1])
		}
		if v < 0 {
			return nil, fmt.Errorf("unexpected value '%d'", v)
		}
		return int64(1), nil
	})

	if err := Publish(conn, -1, 10); err != nil {
		fmt.Println(err)
		return
	}

	fmt.Println("Success!")
}