e2e.go

// Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
// SPDX-License-Identifier: Apache-2.0

// Package e2e is created because:
//
// During test setup, SetupLocalRegistry is called,
// and container tests need to be run before VM tests
// so that the local registry won't be removed by VM tests,
// and container tests can use the images stored in it.
//
// However, by default Ginkgo does not guarantee the order in which specs run [1],
// and Ginkgo doc says that "You should only ever call RunSpecs once" [2],
// which means that we need two binaries that run VM tests and container tests respectively.
//
// We could add ginkgo.Ordered to the top level Ginkgo container,
// but that will make every single spec to run in the order they are defined:
// "Any container nodes nested within a container node will automatically be considered Ordered
// and there is no way to mark a node within an Ordered container as "not Ordered"" [1],
// and we don't want that because it can hide implicit dependencies among tests,
// while each test should be independent unless specially designed.
//
// As a result, we split the tests into `e2e/vm` and `e2e/container` packages
// and extract the common logic into this package.
//
// [1] https://onsi.github.io/ginkgo/#ordered-containers.
// [2] https://onsi.github.io/ginkgo/#mental-model-go-modules-packages-and-tests
package e2e

import (
	"flag"
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"regexp"
	"runtime"

	"github.com/runfinch/common-tests/option"
)

// InstalledTestSubject is the test subject when Finch is installed.
const InstalledTestSubject = "finch"

var (
	// Installed indicates whether the tests are run against installed application.
	Installed = flag.Bool("installed", false, "the flag to show whether the tests are run against installed application")
	// Registry indicates which container registry to pull from.
	Registry = flag.String("registry", "", "used when pulling from registry to test credential helper")
)

// CreateOption creates an option for running e2e tests.
func CreateOption() (*option.Option, error) {
	wd, err := os.Getwd()
	if err != nil {
		return nil, fmt.Errorf("failed to get the current working directory: %w", err)
	}

	subject := filepath.Join(wd, "..", "..", "_output", "bin", "finch")
	if *Installed {
		subject = InstalledTestSubject
	}

	args := []string{subject}
	debug := os.Getenv("DEBUG")
	if len(debug) != 0 {
		args = append(args, "--debug")
	}

	mods := []option.Modifier{}
	if runtime.GOOS == "linux" {
		nerdctlVersion, err := getNerdctlVersion(subject)
		if err != nil {
			return nil, err
		}
		mods = append(mods, option.WithNerdctlVersion(nerdctlVersion))
	}

	o, err := option.New(args, mods...)
	if err != nil {
		return nil, fmt.Errorf("failed to initialize a testing option: %w", err)
	}
	return o, nil
}

func getNerdctlVersion(subject string) (string, error) {
	output, err := exec.Command(subject, "version").CombinedOutput()
	if err != nil {
		return "", fmt.Errorf("failed to run version command: %w", err)
	}
	re := regexp.MustCompile(`(?m)nerdctl:\n\s*Version:\s*v(.*)$`)
	matches := re.FindStringSubmatch(string(output))

	if matches == nil || len(matches) != 2 {
		return "", fmt.Errorf("regexp did not match properly, output: %s", output)
	}

	return matches[1], nil
}