conex

package module
Version: v0.0.1 Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Oct 15, 2019 License: MIT Imports: 14 Imported by: 6

README

Conex GoDoc Build Status Go Report Card

Conex integrates Go testing with Docker so you can easily run your integration tests and benchmarks.

Yes, we did hear you like integrations.

Why?

Integration tests are very good value, they're easy to write and help you catch bugs in a more realistic environment and with most every service and database avaliable as a Docker Container, docker is a great option to run your service dependencies in a clear state. Conex is here to make it simpler by taking care of the following tasks:

  • starting containers
  • automatically creating uniqe names to avoid conflicts
  • deleting containers
  • pull or check images before running tests
  • Wait for a service (tcp, udp) port to accept connections
  • Expose ports

On top of that, Conex providers a driver convention to simplify code reuse across projects.

How?

To use conex, we will leverage TestMain, this will allow us a starting point to connect to docker, pull all the dependent images and only then run the tests.

Simpley call conex.Run(m) where you would run m.Run().

func TestMain(m *testing.M) {
  // If you're planing to use conex.Box directly without
  // using a driver, you can pass your required images
  // after m to conex.Run.
  os.Exit(conex.Run(m))
}

In our tests, we will use driver packages, these packages register their required image with conex and provide you with a native client and take cares of requesting a container from conex.

Here is an example using redis:

func testPing(t *testing.T) {
  redisDb: = 0
  client, container := redis.Box(t, redisDb)
  defer container.Drop() // Return the container.

  // here we can simply use client which is a go-redis
  // client.
}

Boxes

You can find find drivers/box packages for redis, mysql, postgresql, rethinkdb, and many more on github.com/conex.

Example

Here is a complete example using a simple Echo service.

You can create many containers and different services as you want, you can also run multiple tests in parallel without conflict, conex creates the containers with uniqe names that consist of the test id, package path, test name, container, and an ordinal index starting from 0. This avoids container name conflicts across the board.

package example_test

import (
  "os"
  "testing"

  "github.com/omeid/conex"
  "github.com/omeid/conex/echo"
  echolib "github.com/omeid/echo"
)

func TestMain(m *testing.M) {
  os.Exit(conex.Run(m))
}

func TestEcho(t *testing.T) {
  reverse := true

  e, container := echo.Box(t, reverse)
  defer container.Drop() // Return the container.

  say := "hello"
  expect := say
  if reverse {
    expect = echolib.Reverse(say)
  }

  reply, err := e.Say(say)

  if err != nil {
    t.Fatal(err)
  }

  if reply != expect {
    t.Fatalf("\nSaid: %s\nExpected: %s\nGot:      %s\n", say, expect, reply)
  }

}

// You can also use containers in benchmarks!
func BenchmarkEcho(b *testing.B) {

	reverse := false
	say := "hello"
	expect := say

	e, c := echo.Box(b, reverse)
	defer c.Drop()

	for n := 0; n < b.N; n++ {

		reply, err := e.Say(say)

		if err != nil {
			b.Fatal(err)
		}

		if reply != expect {
			b.Fatalf("\nSaid: %s\nExpected: %s\nGot:      %s\n", say, expect, reply)
		}
	}
}

And running tests will yield:

$ go test -v
2017/04/17 22:13:05 
=== conex: Pulling Images
--- Pulling omeid/echo:http (1 of 1)
http: Pulling from omeid/echo
627beaf3eaaf: Already exists 
8800e3417eb1: Already exists 
b6acb96fee14: Already exists 
66be5afddf19: Already exists 
8ca17cdcfc93: Already exists 
792cf0844f5e: Already exists 
26601152322c: Pull complete 
2cb3c6a6d3ee: Pull complete 
Digest: sha256:f6968275ab031d91a3c37e8a9f65b961b5a3df850a90fe4551ecb4724ab3b0a7
Status: Downloaded newer image for omeid/echo:http
=== conex: Pulling Done
2017/04/17 22:13:38 
2017/04/17 22:13:38 
=== conex: Starting your tests.
=== RUN   TestEcho
--- PASS: TestEcho (0.55s)
      conex.go:11: creating (omeid/echo:http: -reverse) as conex_508151185_test-TestEcho-omeid_echo.http_0
      conex.go:11: started (omeid/echo:http: -reverse) as conex_508151185_test-TestEcho-omeid_echo.http_0
PASS
ok    test  33.753s

Drivers Packages

Conex drivers are simple packages that follow a convention to provide a simple interface to the underlying service run on the container. So the user doesn't have to think about containers but the service in their tests.

First, define an image attribute for your package that users can change and register it with conex.

// Image to use for the box.
var Image = "redis:alpine"

func init() {
  conex.Require(func() string { return Image })
}

Then request a container with the required image from conex and setup a client that is connected to the container you created. Return the client and the container.

// Box returns an connect to an echo container based on
// your provided tags.
func Box(t testing.TB, optionally SomeOptions) (your.Client, conex.Container)) {

  conf := &conex.Config{
    Image: Image,
    // Here you may set other options based
    // on the options passed to Box.
  }

  c, con := conex.Box(t, conf)

  opt := &your.Options{
    Addr: c.Address(),
    magic: optionally.SomeMagic,
  }

  client, err := redis.NewClient(opt)

  if err != nil {
    t.Fatal(err)
  }

  return client, con
}

Caveat

Only native docker is support, so Docker for Mac and Docker Machine in general is not supported because of how port forwarding and port maping works.

Is it good?

Yes.

LICENSE

MIT.

Documentation

Overview

Package conex provides easy to use Docker Integration with Testing.

Index

Constants

This section is empty.

Variables

View Source
var (
	// FailReturnCode is used as status code when conex fails to setup during Run.
	// This does not override the return value of testing.M.Run, only when conex
	// fails to even testing.M.Run.
	FailReturnCode = 255
	// PullImages dictates whatever the Manager should attempt to pull the images
	// on run or simply ensure they exist.
	// Note: Pulling images may result into updates.
	PullImages = true
)
View Source
var ErrPortWaitTimedOut = errors.New("wait timeout")

ErrPortWaitTimedOut is returned when Container.Wait reaches maxWait before the port accepts connections.

Functions

func Require

func Require(images ...func() string)

Require adds the image name returned by the provided functions to the list of images pull by the default Manager when Run is called. Used by driver packages, see conex/redis, conex/rethink.

func Run

func Run(m *testing.M, images ...string) int

Run prepares a docker client, pulls the provided list of images and then runs your tests.

Types

type Config

type Config struct {
	Image      string   // Name of the image as it was passed by the operator (e.g. could be symbolic)
	Env        []string // List of environment variable to set in the container
	Cmd        []string // Command to run when starting the container
	Hostname   string   // Hostname
	Domainname string   // Domainname
	User       string   // User that will run the command(s) inside the container, also support user:group
	Expose     []string // Ports to expose, supports the docker command line style syntax proto/port or just port which defaults to tcp
}

Config contains the configuration data about a container.

type Container

type Container interface {
	ID() string
	Name() string
	Image() string
	Address() string

	Drop()

	Wait(port string, timeout time.Duration) error // Wait for the port to respond to tcp/udp.

}

Container is a simple interface to a docker container.

func Box

func Box(t testing.TB, conf *Config) Container

Box creates a new container using the provided image and passes your parameters.

type Manager

type Manager interface {
	Run(m *testing.M, images ...string) int
	Box(t testing.TB, config *Config) Container
}

Manager is the conex container manager.

func New

func New(retcode int, pullImages bool, images ...string) Manager

New returns a new conex manager.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL