docker-compose/pkg/e2e/framework.go

/*
   Copyright 2020 Docker Compose CLI authors

   Licensed under the Apache License, Version 2.0 (the "License");
   you may not use this file except in compliance with the License.
   You may obtain a copy of the License at

       http://www.apache.org/licenses/LICENSE-2.0

   Unless required by applicable law or agreed to in writing, software
   distributed under the License is distributed on an "AS IS" BASIS,
   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   See the License for the specific language governing permissions and
   limitations under the License.
*/

package e2e

import (
	"fmt"
	"io"
	"io/ioutil"
	"net/http"
	"os"
	"path"
	"path/filepath"
	"runtime"
	"strings"
	"testing"
	"time"

	"github.com/pkg/errors"
	"github.com/stretchr/testify/require"
	"gotest.tools/v3/assert"
	"gotest.tools/v3/icmd"
	"gotest.tools/v3/poll"

	"github.com/docker/compose/v2/cmd/compose"
)

var (
	// DockerExecutableName is the OS dependent Docker CLI binary name
	DockerExecutableName = "docker"

	// DockerComposeExecutableName is the OS dependent Docker CLI binary name
	DockerComposeExecutableName = "docker-" + compose.PluginName

	// DockerScanExecutableName is the OS dependent Docker CLI binary name
	DockerScanExecutableName = "docker-scan"
)

func init() {
	if runtime.GOOS == "windows" {
		DockerExecutableName = DockerExecutableName + ".exe"
		DockerComposeExecutableName = DockerComposeExecutableName + ".exe"
		DockerScanExecutableName = DockerScanExecutableName + ".exe"
	}
}

// CLI is used to wrap the CLI for end to end testing
type CLI struct {
	// ConfigDir for Docker configuration (set as DOCKER_CONFIG)
	ConfigDir string

	// HomeDir for tools that look for user files (set as HOME)
	HomeDir string

	// env overrides to apply to every invoked command
	//
	// To populate, use WithEnv when creating a CLI instance.
	env []string
}

// CLIOption to customize behavior for all commands for a CLI instance.
type CLIOption func(c *CLI)

// NewParallelCLI marks the parent test as parallel and returns a CLI instance
// suitable for usage across child tests.
func NewParallelCLI(t *testing.T, opts ...CLIOption) *CLI {
	t.Helper()
	t.Parallel()
	return NewCLI(t, opts...)
}

// NewCLI creates a CLI instance for running E2E tests.
func NewCLI(t testing.TB, opts ...CLIOption) *CLI {
	t.Helper()

	configDir := t.TempDir()
	initializePlugins(t, configDir)

	c := &CLI{
		ConfigDir: configDir,
		HomeDir:   t.TempDir(),
	}

	for _, opt := range opts {
		opt(c)
	}

	return c
}

// WithEnv sets environment variables that will be passed to commands.
func WithEnv(env ...string) CLIOption {
	return func(c *CLI) {
		c.env = append(c.env, env...)
	}
}

// initializePlugins copies the necessary plugin files to the temporary config
// directory for the test.
func initializePlugins(t testing.TB, d string) {
	t.Helper()

	t.Cleanup(func() {
		if t.Failed() {
			conf, _ := ioutil.ReadFile(filepath.Join(d, "config.json"))
			t.Errorf("Config: %s\n", string(conf))
			t.Error("Contents of config dir:")
			for _, p := range dirContents(d) {
				t.Errorf(p)
			}
		}
		_ = os.RemoveAll(d)
	})

	_ = os.MkdirAll(filepath.Join(d, "cli-plugins"), 0755)
	composePlugin, err := findExecutable(DockerComposeExecutableName, []string{"../../bin", "../../../bin"})
	if os.IsNotExist(err) {
		fmt.Println("WARNING: docker-compose cli-plugin not found")
	}
	if err == nil {
		err = CopyFile(composePlugin, filepath.Join(d, "cli-plugins", DockerComposeExecutableName))
		if err != nil {
			panic(err)
		}
		// We don't need a functional scan plugin, but a valid plugin binary
		err = CopyFile(composePlugin, filepath.Join(d, "cli-plugins", DockerScanExecutableName))
		if err != nil {
			panic(err)
		}
	}
}

func dirContents(dir string) []string {
	var res []string
	_ = filepath.Walk(dir, func(path string, info os.FileInfo, err error) error {
		res = append(res, path)
		return nil
	})
	return res
}

func findExecutable(executableName string, paths []string) (string, error) {
	for _, p := range paths {
		bin, err := filepath.Abs(path.Join(p, executableName))
		if err != nil {
			return "", err
		}

		if _, err := os.Stat(bin); os.IsNotExist(err) {
			continue
		}

		return bin, nil
	}

	return "", errors.Wrap(os.ErrNotExist, "executable not found")
}

// CopyFile copies a file from a sourceFile to a destinationFile setting permissions to 0755
func CopyFile(sourceFile string, destinationFile string) error {
	src, err := os.Open(sourceFile)
	if err != nil {
		return err
	}
	// nolint: errcheck
	defer src.Close()

	dst, err := os.OpenFile(destinationFile, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0755)
	if err != nil {
		return err
	}
	// nolint: errcheck
	defer dst.Close()

	if _, err = io.Copy(dst, src); err != nil {
		return err
	}

	return err
}

// BaseEnvironment provides the minimal environment variables used across all
// Docker / Compose commands.
func (c *CLI) BaseEnvironment() []string {
	return []string{
		"HOME=" + c.HomeDir,
		"USER=" + os.Getenv("USER"),
		"DOCKER_CONFIG=" + c.ConfigDir,
		"KUBECONFIG=invalid",
	}
}

// NewCmd creates a cmd object configured with the test environment set
func (c *CLI) NewCmd(command string, args ...string) icmd.Cmd {
	return icmd.Cmd{
		Command: append([]string{command}, args...),
		Env:     append(c.BaseEnvironment(), c.env...),
	}
}

// NewCmdWithEnv creates a cmd object configured with the test environment set with additional env vars
func (c *CLI) NewCmdWithEnv(envvars []string, command string, args ...string) icmd.Cmd {
	// base env -> CLI overrides -> cmd overrides
	cmdEnv := append(c.BaseEnvironment(), c.env...)
	cmdEnv = append(cmdEnv, envvars...)
	return icmd.Cmd{
		Command: append([]string{command}, args...),
		Env:     cmdEnv,
	}
}

// MetricsSocket get the path where test metrics will be sent
func (c *CLI) MetricsSocket() string {
	return filepath.Join(c.ConfigDir, "./docker-cli.sock")
}

// NewDockerCmd creates a docker cmd without running it
func (c *CLI) NewDockerCmd(args ...string) icmd.Cmd {
	return c.NewCmd(DockerExecutableName, args...)
}

// RunDockerOrExitError runs a docker command and returns a result
func (c *CLI) RunDockerOrExitError(t testing.TB, args ...string) *icmd.Result {
	fmt.Printf("\t[%s] docker %s\n", t.Name(), strings.Join(args, " "))
	return icmd.RunCmd(c.NewDockerCmd(args...))
}

// RunCmd runs a command, expects no error and returns a result
func (c *CLI) RunCmd(t testing.TB, args ...string) *icmd.Result {
	fmt.Printf("\t[%s] %s\n", t.Name(), strings.Join(args, " "))
	assert.Assert(t, len(args) >= 1, "require at least one command in parameters")
	res := icmd.RunCmd(c.NewCmd(args[0], args[1:]...))
	res.Assert(t, icmd.Success)
	return res
}

// RunCmdInDir runs a command in a given dir, expects no error and returns a result
func (c *CLI) RunCmdInDir(t testing.TB, dir string, args ...string) *icmd.Result {
	fmt.Printf("\t[%s] %s\n", t.Name(), strings.Join(args, " "))
	assert.Assert(t, len(args) >= 1, "require at least one command in parameters")
	cmd := c.NewCmd(args[0], args[1:]...)
	cmd.Dir = dir
	res := icmd.RunCmd(cmd)
	res.Assert(t, icmd.Success)
	return res
}

// RunDockerCmd runs a docker command, expects no error and returns a result
func (c *CLI) RunDockerCmd(t testing.TB, args ...string) *icmd.Result {
	if len(args) > 0 && args[0] == compose.PluginName {
		t.Fatal("This test called 'RunDockerCmd' for 'compose'. Please prefer 'RunDockerComposeCmd' to be able to test as a plugin and standalone")
	}
	res := c.RunDockerOrExitError(t, args...)
	res.Assert(t, icmd.Success)
	return res
}

// RunDockerComposeCmd runs a docker compose command, expects no error and returns a result
func (c *CLI) RunDockerComposeCmd(t testing.TB, args ...string) *icmd.Result {
	res := c.RunDockerComposeCmdNoCheck(t, args...)
	res.Assert(t, icmd.Success)
	return res
}

// RunDockerComposeCmdNoCheck runs a docker compose command, don't presume of any expectation and returns a result
func (c *CLI) RunDockerComposeCmdNoCheck(t testing.TB, args ...string) *icmd.Result {
	return icmd.RunCmd(c.NewDockerComposeCmd(t, args...))
}

// NewDockerComposeCmd creates a command object for Compose, either in plugin
// or standalone mode (based on build tags).
func (c *CLI) NewDockerComposeCmd(t testing.TB, args ...string) icmd.Cmd {
	t.Helper()
	if composeStandaloneMode {
		return c.NewCmd(ComposeStandalonePath(t), args...)
	}
	args = append([]string{"compose"}, args...)
	return c.NewCmd(DockerExecutableName, args...)
}

// ComposeStandalonePath returns the path to the locally-built Compose
// standalone binary from the repo.
//
// This function will fail the test immediately if invoked when not running
// in standalone test mode.
func ComposeStandalonePath(t testing.TB) string {
	t.Helper()
	if !composeStandaloneMode {
		require.Fail(t, "Not running in standalone mode")
	}
	composeBinary, err := findExecutable(DockerComposeExecutableName, []string{"../../bin", "../../../bin"})
	require.NoError(t, err, "Could not find standalone Compose binary (%q)",
		DockerComposeExecutableName)
	return composeBinary
}

// StdoutContains returns a predicate on command result expecting a string in stdout
func StdoutContains(expected string) func(*icmd.Result) bool {
	return func(res *icmd.Result) bool {
		return strings.Contains(res.Stdout(), expected)
	}
}

// WaitForCmdResult try to execute a cmd until resulting output matches given predicate
func (c *CLI) WaitForCmdResult(t testing.TB, command icmd.Cmd, predicate func(*icmd.Result) bool, timeout time.Duration, delay time.Duration) {
	assert.Assert(t, timeout.Nanoseconds() > delay.Nanoseconds(), "timeout must be greater than delay")
	var res *icmd.Result
	checkStopped := func(logt poll.LogT) poll.Result {
		fmt.Printf("\t[%s] %s\n", t.Name(), strings.Join(command.Command, " "))
		res = icmd.RunCmd(command)
		if !predicate(res) {
			return poll.Continue("Cmd output did not match requirement: %q", res.Combined())
		}
		return poll.Success()
	}
	poll.WaitOn(t, checkStopped, poll.WithDelay(delay), poll.WithTimeout(timeout))
}

// WaitForCondition wait for predicate to execute to true
func (c *CLI) WaitForCondition(t testing.TB, predicate func() (bool, string), timeout time.Duration, delay time.Duration) {
	checkStopped := func(logt poll.LogT) poll.Result {
		pass, description := predicate()
		if !pass {
			return poll.Continue("Condition not met: %q", description)
		}
		return poll.Success()
	}
	poll.WaitOn(t, checkStopped, poll.WithDelay(delay), poll.WithTimeout(timeout))
}

// Lines split output into lines
func Lines(output string) []string {
	return strings.Split(strings.TrimSpace(output), "\n")
}

// HTTPGetWithRetry performs an HTTP GET on an `endpoint`, using retryDelay also as a request timeout.
// In the case of an error or the response status is not the expeted one, it retries the same request,
// returning the response body as a string (empty if we could not reach it)
func HTTPGetWithRetry(t testing.TB, endpoint string, expectedStatus int, retryDelay time.Duration, timeout time.Duration) string {
	var (
		r   *http.Response
		err error
	)
	client := &http.Client{
		Timeout: retryDelay,
	}
	fmt.Printf("\t[%s] GET %s\n", t.Name(), endpoint)
	checkUp := func(t poll.LogT) poll.Result {
		r, err = client.Get(endpoint)
		if err != nil {
			return poll.Continue("reaching %q: Error %s", endpoint, err.Error())
		}
		if r.StatusCode == expectedStatus {
			return poll.Success()
		}
		return poll.Continue("reaching %q: %d != %d", endpoint, r.StatusCode, expectedStatus)
	}
	poll.WaitOn(t, checkUp, poll.WithDelay(retryDelay), poll.WithTimeout(timeout))
	if r != nil {
		b, err := ioutil.ReadAll(r.Body)
		assert.NilError(t, err)
		return string(b)
	}
	return ""
}