Adding upstream version 1.21.4.HEADupstream/1.21.4upstreamdebian

Signed-off-by: Daniel Baumann <daniel@debian.org>

14 files changed, 1589 insertions, 0 deletions

diff --git a/pkg/common/cartesian.go b/pkg/common/cartesian.go
new file mode 100644
index 0000000..9cd6065
--- /dev/null
+++ b/pkg/common/cartesian.go
@@ -0,0 +1,54 @@
+package common
+
+// CartesianProduct takes map of lists and returns list of unique tuples
+func CartesianProduct(mapOfLists map[string][]interface{}) []map[string]interface{} {
+	listNames := make([]string, 0)
+	lists := make([][]interface{}, 0)
+	for k, v := range mapOfLists {
+		listNames = append(listNames, k)
+		lists = append(lists, v)
+	}
+
+	listCart := cartN(lists...)
+
+	rtn := make([]map[string]interface{}, 0)
+	for _, list := range listCart {
+		vMap := make(map[string]interface{})
+		for i, v := range list {
+			vMap[listNames[i]] = v
+		}
+		rtn = append(rtn, vMap)
+	}
+	return rtn
+}
+
+func cartN(a ...[]interface{}) [][]interface{} {
+	c := 1
+	for _, a := range a {
+		c *= len(a)
+	}
+	if c == 0 || len(a) == 0 {
+		return nil
+	}
+	p := make([][]interface{}, c)
+	b := make([]interface{}, c*len(a))
+	n := make([]int, len(a))
+	s := 0
+	for i := range p {
+		e := s + len(a)
+		pi := b[s:e]
+		p[i] = pi
+		s = e
+		for j, n := range n {
+			pi[j] = a[j][n]
+		}
+		for j := len(n) - 1; j >= 0; j-- {
+			n[j]++
+			if n[j] < len(a[j]) {
+				break
+			}
+			n[j] = 0
+		}
+	}
+	return p
+}
diff --git a/pkg/common/cartesian_test.go b/pkg/common/cartesian_test.go
new file mode 100644
index 0000000..c49de06
--- /dev/null
+++ b/pkg/common/cartesian_test.go
@@ -0,0 +1,39 @@
+package common
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestCartesianProduct(t *testing.T) {
+	assert := assert.New(t)
+	input := map[string][]interface{}{
+		"foo": {1, 2, 3, 4},
+		"bar": {"a", "b", "c"},
+		"baz": {false, true},
+	}
+
+	output := CartesianProduct(input)
+	assert.Len(output, 24)
+
+	for _, v := range output {
+		assert.Len(v, 3)
+
+		assert.Contains(v, "foo")
+		assert.Contains(v, "bar")
+		assert.Contains(v, "baz")
+	}
+
+	input = map[string][]interface{}{
+		"foo": {1, 2, 3, 4},
+		"bar": {},
+		"baz": {false, true},
+	}
+	output = CartesianProduct(input)
+	assert.Len(output, 0)
+
+	input = map[string][]interface{}{}
+	output = CartesianProduct(input)
+	assert.Len(output, 0)
+}
diff --git a/pkg/common/draw.go b/pkg/common/draw.go
new file mode 100644
index 0000000..b5b21fe
--- /dev/null
+++ b/pkg/common/draw.go
@@ -0,0 +1,143 @@
+package common
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strings"
+)
+
+// Style is a specific style
+type Style int
+
+// Styles
+const (
+	StyleDoubleLine = iota
+	StyleSingleLine
+	StyleDashedLine
+	StyleNoLine
+)
+
+// NewPen creates a new pen
+func NewPen(style Style, color int) *Pen {
+	bgcolor := 49
+	if os.Getenv("CLICOLOR") == "0" {
+		color = 0
+		bgcolor = 0
+	}
+	return &Pen{
+		style:   style,
+		color:   color,
+		bgcolor: bgcolor,
+	}
+}
+
+type styleDef struct {
+	cornerTL string
+	cornerTR string
+	cornerBL string
+	cornerBR string
+	lineH    string
+	lineV    string
+}
+
+var styleDefs = []styleDef{
+	{"\u2554", "\u2557", "\u255a", "\u255d", "\u2550", "\u2551"},
+	{"\u256d", "\u256e", "\u2570", "\u256f", "\u2500", "\u2502"},
+	{"\u250c", "\u2510", "\u2514", "\u2518", "\u254c", "\u254e"},
+	{" ", " ", " ", " ", " ", " "},
+}
+
+// Pen struct
+type Pen struct {
+	style   Style
+	color   int
+	bgcolor int
+}
+
+// Drawing struct
+type Drawing struct {
+	buf   *strings.Builder
+	width int
+}
+
+func (p *Pen) drawTopBars(buf io.Writer, labels ...string) {
+	style := styleDefs[p.style]
+	for _, label := range labels {
+		bar := strings.Repeat(style.lineH, len(label)+2)
+		fmt.Fprintf(buf, " ")
+		fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
+		fmt.Fprintf(buf, "%s%s%s", style.cornerTL, bar, style.cornerTR)
+		fmt.Fprintf(buf, "\x1b[%dm", 0)
+	}
+	fmt.Fprintf(buf, "\n")
+}
+func (p *Pen) drawBottomBars(buf io.Writer, labels ...string) {
+	style := styleDefs[p.style]
+	for _, label := range labels {
+		bar := strings.Repeat(style.lineH, len(label)+2)
+		fmt.Fprintf(buf, " ")
+		fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
+		fmt.Fprintf(buf, "%s%s%s", style.cornerBL, bar, style.cornerBR)
+		fmt.Fprintf(buf, "\x1b[%dm", 0)
+	}
+	fmt.Fprintf(buf, "\n")
+}
+func (p *Pen) drawLabels(buf io.Writer, labels ...string) {
+	style := styleDefs[p.style]
+	for _, label := range labels {
+		fmt.Fprintf(buf, " ")
+		fmt.Fprintf(buf, "\x1b[%d;%dm", p.color, p.bgcolor)
+		fmt.Fprintf(buf, "%s %s %s", style.lineV, label, style.lineV)
+		fmt.Fprintf(buf, "\x1b[%dm", 0)
+	}
+	fmt.Fprintf(buf, "\n")
+}
+
+// DrawArrow between boxes
+func (p *Pen) DrawArrow() *Drawing {
+	drawing := &Drawing{
+		buf:   new(strings.Builder),
+		width: 1,
+	}
+	fmt.Fprintf(drawing.buf, "\x1b[%dm", p.color)
+	fmt.Fprintf(drawing.buf, "\u2b07")
+	fmt.Fprintf(drawing.buf, "\x1b[%dm", 0)
+	return drawing
+}
+
+// DrawBoxes to draw boxes
+func (p *Pen) DrawBoxes(labels ...string) *Drawing {
+	width := 0
+	for _, l := range labels {
+		width += len(l) + 2 + 2 + 1
+	}
+	drawing := &Drawing{
+		buf:   new(strings.Builder),
+		width: width,
+	}
+	p.drawTopBars(drawing.buf, labels...)
+	p.drawLabels(drawing.buf, labels...)
+	p.drawBottomBars(drawing.buf, labels...)
+
+	return drawing
+}
+
+// Draw to writer
+func (d *Drawing) Draw(writer io.Writer, centerOnWidth int) {
+	padSize := (centerOnWidth - d.GetWidth()) / 2
+	if padSize < 0 {
+		padSize = 0
+	}
+	for _, l := range strings.Split(d.buf.String(), "\n") {
+		if len(l) > 0 {
+			padding := strings.Repeat(" ", padSize)
+			fmt.Fprintf(writer, "%s%s\n", padding, l)
+		}
+	}
+}
+
+// GetWidth of drawing
+func (d *Drawing) GetWidth() int {
+	return d.width
+}
diff --git a/pkg/common/dryrun.go b/pkg/common/dryrun.go
new file mode 100644
index 0000000..2d5a14e
--- /dev/null
+++ b/pkg/common/dryrun.go
@@ -0,0 +1,25 @@
+package common
+
+import (
+	"context"
+)
+
+type dryrunContextKey string
+
+const dryrunContextKeyVal = dryrunContextKey("dryrun")
+
+// Dryrun returns true if the current context is dryrun
+func Dryrun(ctx context.Context) bool {
+	val := ctx.Value(dryrunContextKeyVal)
+	if val != nil {
+		if dryrun, ok := val.(bool); ok {
+			return dryrun
+		}
+	}
+	return false
+}
+
+// WithDryrun adds a value to the context for dryrun
+func WithDryrun(ctx context.Context, dryrun bool) context.Context {
+	return context.WithValue(ctx, dryrunContextKeyVal, dryrun)
+}
diff --git a/pkg/common/executor.go b/pkg/common/executor.go
new file mode 100644
index 0000000..a5eb079
--- /dev/null
+++ b/pkg/common/executor.go
@@ -0,0 +1,196 @@
+package common
+
+import (
+	"context"
+	"fmt"
+
+	log "github.com/sirupsen/logrus"
+)
+
+// Warning that implements `error` but safe to ignore
+type Warning struct {
+	Message string
+}
+
+// Error the contract for error
+func (w Warning) Error() string {
+	return w.Message
+}
+
+// Warningf create a warning
+func Warningf(format string, args ...interface{}) Warning {
+	w := Warning{
+		Message: fmt.Sprintf(format, args...),
+	}
+	return w
+}
+
+// Executor define contract for the steps of a workflow
+type Executor func(ctx context.Context) error
+
+// Conditional define contract for the conditional predicate
+type Conditional func(ctx context.Context) bool
+
+// NewInfoExecutor is an executor that logs messages
+func NewInfoExecutor(format string, args ...interface{}) Executor {
+	return func(ctx context.Context) error {
+		logger := Logger(ctx)
+		logger.Infof(format, args...)
+		return nil
+	}
+}
+
+// NewDebugExecutor is an executor that logs messages
+func NewDebugExecutor(format string, args ...interface{}) Executor {
+	return func(ctx context.Context) error {
+		logger := Logger(ctx)
+		logger.Debugf(format, args...)
+		return nil
+	}
+}
+
+// NewPipelineExecutor creates a new executor from a series of other executors
+func NewPipelineExecutor(executors ...Executor) Executor {
+	if len(executors) == 0 {
+		return func(ctx context.Context) error {
+			return nil
+		}
+	}
+	var rtn Executor
+	for _, executor := range executors {
+		if rtn == nil {
+			rtn = executor
+		} else {
+			rtn = rtn.Then(executor)
+		}
+	}
+	return rtn
+}
+
+// NewConditionalExecutor creates a new executor based on conditions
+func NewConditionalExecutor(conditional Conditional, trueExecutor Executor, falseExecutor Executor) Executor {
+	return func(ctx context.Context) error {
+		if conditional(ctx) {
+			if trueExecutor != nil {
+				return trueExecutor(ctx)
+			}
+		} else {
+			if falseExecutor != nil {
+				return falseExecutor(ctx)
+			}
+		}
+		return nil
+	}
+}
+
+// NewErrorExecutor creates a new executor that always errors out
+func NewErrorExecutor(err error) Executor {
+	return func(ctx context.Context) error {
+		return err
+	}
+}
+
+// NewParallelExecutor creates a new executor from a parallel of other executors
+func NewParallelExecutor(parallel int, executors ...Executor) Executor {
+	return func(ctx context.Context) error {
+		work := make(chan Executor, len(executors))
+		errs := make(chan error, len(executors))
+
+		if 1 > parallel {
+			log.Infof("Parallel tasks (%d) below minimum, setting to 1", parallel)
+			parallel = 1
+		}
+
+		for i := 0; i < parallel; i++ {
+			go func(work <-chan Executor, errs chan<- error) {
+				for executor := range work {
+					errs <- executor(ctx)
+				}
+			}(work, errs)
+		}
+
+		for i := 0; i < len(executors); i++ {
+			work <- executors[i]
+		}
+		close(work)
+
+		// Executor waits all executors to cleanup these resources.
+		var firstErr error
+		for i := 0; i < len(executors); i++ {
+			err := <-errs
+			if firstErr == nil {
+				firstErr = err
+			}
+		}
+
+		if err := ctx.Err(); err != nil {
+			return err
+		}
+		return firstErr
+	}
+}
+
+// Then runs another executor if this executor succeeds
+func (e Executor) Then(then Executor) Executor {
+	return func(ctx context.Context) error {
+		err := e(ctx)
+		if err != nil {
+			switch err.(type) {
+			case Warning:
+				Logger(ctx).Warning(err.Error())
+			default:
+				return err
+			}
+		}
+		if ctx.Err() != nil {
+			return ctx.Err()
+		}
+		return then(ctx)
+	}
+}
+
+// If only runs this executor if conditional is true
+func (e Executor) If(conditional Conditional) Executor {
+	return func(ctx context.Context) error {
+		if conditional(ctx) {
+			return e(ctx)
+		}
+		return nil
+	}
+}
+
+// IfNot only runs this executor if conditional is true
+func (e Executor) IfNot(conditional Conditional) Executor {
+	return func(ctx context.Context) error {
+		if !conditional(ctx) {
+			return e(ctx)
+		}
+		return nil
+	}
+}
+
+// IfBool only runs this executor if conditional is true
+func (e Executor) IfBool(conditional bool) Executor {
+	return e.If(func(ctx context.Context) bool {
+		return conditional
+	})
+}
+
+// Finally adds an executor to run after other executor
+func (e Executor) Finally(finally Executor) Executor {
+	return func(ctx context.Context) error {
+		err := e(ctx)
+		err2 := finally(ctx)
+		if err2 != nil {
+			return fmt.Errorf("Error occurred running finally: %v (original error: %v)", err2, err)
+		}
+		return err
+	}
+}
+
+// Not return an inverted conditional
+func (c Conditional) Not() Conditional {
+	return func(ctx context.Context) bool {
+		return !c(ctx)
+	}
+}
diff --git a/pkg/common/executor_test.go b/pkg/common/executor_test.go
new file mode 100644
index 0000000..e70c638
--- /dev/null
+++ b/pkg/common/executor_test.go
@@ -0,0 +1,152 @@
+package common
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestNewWorkflow(t *testing.T) {
+	assert := assert.New(t)
+
+	ctx := context.Background()
+
+	// empty
+	emptyWorkflow := NewPipelineExecutor()
+	assert.Nil(emptyWorkflow(ctx))
+
+	// error case
+	errorWorkflow := NewErrorExecutor(fmt.Errorf("test error"))
+	assert.NotNil(errorWorkflow(ctx))
+
+	// multiple success case
+	runcount := 0
+	successWorkflow := NewPipelineExecutor(
+		func(ctx context.Context) error {
+			runcount++
+			return nil
+		},
+		func(ctx context.Context) error {
+			runcount++
+			return nil
+		})
+	assert.Nil(successWorkflow(ctx))
+	assert.Equal(2, runcount)
+}
+
+func TestNewConditionalExecutor(t *testing.T) {
+	assert := assert.New(t)
+
+	ctx := context.Background()
+
+	trueCount := 0
+	falseCount := 0
+
+	err := NewConditionalExecutor(func(ctx context.Context) bool {
+		return false
+	}, func(ctx context.Context) error {
+		trueCount++
+		return nil
+	}, func(ctx context.Context) error {
+		falseCount++
+		return nil
+	})(ctx)
+
+	assert.Nil(err)
+	assert.Equal(0, trueCount)
+	assert.Equal(1, falseCount)
+
+	err = NewConditionalExecutor(func(ctx context.Context) bool {
+		return true
+	}, func(ctx context.Context) error {
+		trueCount++
+		return nil
+	}, func(ctx context.Context) error {
+		falseCount++
+		return nil
+	})(ctx)
+
+	assert.Nil(err)
+	assert.Equal(1, trueCount)
+	assert.Equal(1, falseCount)
+}
+
+func TestNewParallelExecutor(t *testing.T) {
+	assert := assert.New(t)
+
+	ctx := context.Background()
+
+	count := 0
+	activeCount := 0
+	maxCount := 0
+	emptyWorkflow := NewPipelineExecutor(func(ctx context.Context) error {
+		count++
+
+		activeCount++
+		if activeCount > maxCount {
+			maxCount = activeCount
+		}
+		time.Sleep(2 * time.Second)
+		activeCount--
+
+		return nil
+	})
+
+	err := NewParallelExecutor(2, emptyWorkflow, emptyWorkflow, emptyWorkflow)(ctx)
+
+	assert.Equal(3, count, "should run all 3 executors")
+	assert.Equal(2, maxCount, "should run at most 2 executors in parallel")
+	assert.Nil(err)
+
+	// Reset to test running the executor with 0 parallelism
+	count = 0
+	activeCount = 0
+	maxCount = 0
+
+	errSingle := NewParallelExecutor(0, emptyWorkflow, emptyWorkflow, emptyWorkflow)(ctx)
+
+	assert.Equal(3, count, "should run all 3 executors")
+	assert.Equal(1, maxCount, "should run at most 1 executors in parallel")
+	assert.Nil(errSingle)
+}
+
+func TestNewParallelExecutorFailed(t *testing.T) {
+	assert := assert.New(t)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	count := 0
+	errorWorkflow := NewPipelineExecutor(func(ctx context.Context) error {
+		count++
+		return fmt.Errorf("fake error")
+	})
+	err := NewParallelExecutor(1, errorWorkflow)(ctx)
+	assert.Equal(1, count)
+	assert.ErrorIs(context.Canceled, err)
+}
+
+func TestNewParallelExecutorCanceled(t *testing.T) {
+	assert := assert.New(t)
+
+	ctx, cancel := context.WithCancel(context.Background())
+	cancel()
+
+	errExpected := fmt.Errorf("fake error")
+
+	count := 0
+	successWorkflow := NewPipelineExecutor(func(ctx context.Context) error {
+		count++
+		return nil
+	})
+	errorWorkflow := NewPipelineExecutor(func(ctx context.Context) error {
+		count++
+		return errExpected
+	})
+	err := NewParallelExecutor(3, errorWorkflow, successWorkflow, successWorkflow)(ctx)
+	assert.Equal(3, count)
+	assert.Error(errExpected, err)
+}
diff --git a/pkg/common/file.go b/pkg/common/file.go
new file mode 100644
index 0000000..09c2102
--- /dev/null
+++ b/pkg/common/file.go
@@ -0,0 +1,73 @@
+package common
+
+import (
+	"fmt"
+	"io"
+	"os"
+)
+
+// CopyFile copy file
+func CopyFile(source string, dest string) (err error) {
+	sourcefile, err := os.Open(source)
+	if err != nil {
+		return err
+	}
+
+	defer sourcefile.Close()
+
+	destfile, err := os.Create(dest)
+	if err != nil {
+		return err
+	}
+
+	defer destfile.Close()
+
+	_, err = io.Copy(destfile, sourcefile)
+	if err == nil {
+		sourceinfo, err := os.Stat(source)
+		if err != nil {
+			_ = os.Chmod(dest, sourceinfo.Mode())
+		}
+	}
+
+	return
+}
+
+// CopyDir recursive copy of directory
+func CopyDir(source string, dest string) (err error) {
+	// get properties of source dir
+	sourceinfo, err := os.Stat(source)
+	if err != nil {
+		return err
+	}
+
+	// create dest dir
+
+	err = os.MkdirAll(dest, sourceinfo.Mode())
+	if err != nil {
+		return err
+	}
+
+	objects, err := os.ReadDir(source)
+
+	for _, obj := range objects {
+		sourcefilepointer := source + "/" + obj.Name()
+
+		destinationfilepointer := dest + "/" + obj.Name()
+
+		if obj.IsDir() {
+			// create sub-directories - recursively
+			err = CopyDir(sourcefilepointer, destinationfilepointer)
+			if err != nil {
+				fmt.Println(err)
+			}
+		} else {
+			// perform copy
+			err = CopyFile(sourcefilepointer, destinationfilepointer)
+			if err != nil {
+				fmt.Println(err)
+			}
+		}
+	}
+	return err
+}
diff --git a/pkg/common/git/git.go b/pkg/common/git/git.go
new file mode 100644
index 0000000..c7ee889
--- /dev/null
+++ b/pkg/common/git/git.go
@@ -0,0 +1,418 @@
+package git
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"os"
+	"path"
+	"regexp"
+	"strings"
+	"sync"
+
+	"github.com/go-git/go-git/v5"
+	"github.com/go-git/go-git/v5/config"
+	"github.com/go-git/go-git/v5/plumbing"
+	"github.com/go-git/go-git/v5/plumbing/storer"
+	"github.com/go-git/go-git/v5/plumbing/transport/http"
+	"github.com/mattn/go-isatty"
+	log "github.com/sirupsen/logrus"
+
+	"github.com/nektos/act/pkg/common"
+)
+
+var (
+	codeCommitHTTPRegex = regexp.MustCompile(`^https?://git-codecommit\.(.+)\.amazonaws.com/v1/repos/(.+)$`)
+	codeCommitSSHRegex  = regexp.MustCompile(`ssh://git-codecommit\.(.+)\.amazonaws.com/v1/repos/(.+)$`)
+	githubHTTPRegex     = regexp.MustCompile(`^https?://.*github.com.*/(.+)/(.+?)(?:.git)?$`)
+	githubSSHRegex      = regexp.MustCompile(`github.com[:/](.+)/(.+?)(?:.git)?$`)
+
+	cloneLock sync.Mutex
+
+	ErrShortRef = errors.New("short SHA references are not supported")
+	ErrNoRepo   = errors.New("unable to find git repo")
+)
+
+type Error struct {
+	err    error
+	commit string
+}
+
+func (e *Error) Error() string {
+	return e.err.Error()
+}
+
+func (e *Error) Unwrap() error {
+	return e.err
+}
+
+func (e *Error) Commit() string {
+	return e.commit
+}
+
+// FindGitRevision get the current git revision
+func FindGitRevision(ctx context.Context, file string) (shortSha string, sha string, err error) {
+	logger := common.Logger(ctx)
+
+	gitDir, err := git.PlainOpenWithOptions(
+		file,
+		&git.PlainOpenOptions{
+			DetectDotGit:          true,
+			EnableDotGitCommonDir: true,
+		},
+	)
+
+	if err != nil {
+		logger.WithError(err).Error("path", file, "not located inside a git repository")
+		return "", "", err
+	}
+
+	head, err := gitDir.Reference(plumbing.HEAD, true)
+	if err != nil {
+		return "", "", err
+	}
+
+	if head.Hash().IsZero() {
+		return "", "", fmt.Errorf("HEAD sha1 could not be resolved")
+	}
+
+	hash := head.Hash().String()
+
+	logger.Debugf("Found revision: %s", hash)
+	return hash[:7], strings.TrimSpace(hash), nil
+}
+
+// FindGitRef get the current git ref
+func FindGitRef(ctx context.Context, file string) (string, error) {
+	logger := common.Logger(ctx)
+
+	logger.Debugf("Loading revision from git directory")
+	_, ref, err := FindGitRevision(ctx, file)
+	if err != nil {
+		return "", err
+	}
+
+	logger.Debugf("HEAD points to '%s'", ref)
+
+	// Prefer the git library to iterate over the references and find a matching tag or branch.
+	var refTag = ""
+	var refBranch = ""
+	repo, err := git.PlainOpenWithOptions(
+		file,
+		&git.PlainOpenOptions{
+			DetectDotGit:          true,
+			EnableDotGitCommonDir: true,
+		},
+	)
+
+	if err != nil {
+		return "", err
+	}
+
+	iter, err := repo.References()
+	if err != nil {
+		return "", err
+	}
+
+	// find the reference that matches the revision's has
+	err = iter.ForEach(func(r *plumbing.Reference) error {
+		/* tags and branches will have the same hash
+		 * when a user checks out a tag, it is not mentioned explicitly
+		 * in the go-git package, we must identify the revision
+		 * then check if any tag matches that revision,
+		 * if so then we checked out a tag
+		 * else we look for branches and if matches,
+		 * it means we checked out a branch
+		 *
+		 * If a branches matches first we must continue and check all tags (all references)
+		 * in case we match with a tag later in the interation
+		 */
+		if r.Hash().String() == ref {
+			if r.Name().IsTag() {
+				refTag = r.Name().String()
+			}
+			if r.Name().IsBranch() {
+				refBranch = r.Name().String()
+			}
+		}
+
+		// we found what we where looking for
+		if refTag != "" && refBranch != "" {
+			return storer.ErrStop
+		}
+
+		return nil
+	})
+
+	if err != nil {
+		return "", err
+	}
+
+	// order matters here see above comment.
+	if refTag != "" {
+		return refTag, nil
+	}
+	if refBranch != "" {
+		return refBranch, nil
+	}
+
+	return "", fmt.Errorf("failed to identify reference (tag/branch) for the checked-out revision '%s'", ref)
+}
+
+// FindGithubRepo get the repo
+func FindGithubRepo(ctx context.Context, file, githubInstance, remoteName string) (string, error) {
+	if remoteName == "" {
+		remoteName = "origin"
+	}
+
+	url, err := findGitRemoteURL(ctx, file, remoteName)
+	if err != nil {
+		return "", err
+	}
+	_, slug, err := findGitSlug(url, githubInstance)
+	return slug, err
+}
+
+func findGitRemoteURL(_ context.Context, file, remoteName string) (string, error) {
+	repo, err := git.PlainOpenWithOptions(
+		file,
+		&git.PlainOpenOptions{
+			DetectDotGit:          true,
+			EnableDotGitCommonDir: true,
+		},
+	)
+	if err != nil {
+		return "", err
+	}
+
+	remote, err := repo.Remote(remoteName)
+	if err != nil {
+		return "", err
+	}
+
+	if len(remote.Config().URLs) < 1 {
+		return "", fmt.Errorf("remote '%s' exists but has no URL", remoteName)
+	}
+
+	return remote.Config().URLs[0], nil
+}
+
+func findGitSlug(url string, githubInstance string) (string, string, error) {
+	if matches := codeCommitHTTPRegex.FindStringSubmatch(url); matches != nil {
+		return "CodeCommit", matches[2], nil
+	} else if matches := codeCommitSSHRegex.FindStringSubmatch(url); matches != nil {
+		return "CodeCommit", matches[2], nil
+	} else if matches := githubHTTPRegex.FindStringSubmatch(url); matches != nil {
+		return "GitHub", fmt.Sprintf("%s/%s", matches[1], matches[2]), nil
+	} else if matches := githubSSHRegex.FindStringSubmatch(url); matches != nil {
+		return "GitHub", fmt.Sprintf("%s/%s", matches[1], matches[2]), nil
+	} else if githubInstance != "github.com" {
+		gheHTTPRegex := regexp.MustCompile(fmt.Sprintf(`^https?://%s/(.+)/(.+?)(?:.git)?$`, githubInstance))
+		gheSSHRegex := regexp.MustCompile(fmt.Sprintf(`%s[:/](.+)/(.+?)(?:.git)?$`, githubInstance))
+		if matches := gheHTTPRegex.FindStringSubmatch(url); matches != nil {
+			return "GitHubEnterprise", fmt.Sprintf("%s/%s", matches[1], matches[2]), nil
+		} else if matches := gheSSHRegex.FindStringSubmatch(url); matches != nil {
+			return "GitHubEnterprise", fmt.Sprintf("%s/%s", matches[1], matches[2]), nil
+		}
+	}
+	return "", url, nil
+}
+
+// NewGitCloneExecutorInput the input for the NewGitCloneExecutor
+type NewGitCloneExecutorInput struct {
+	URL         string
+	Ref         string
+	Dir         string
+	Token       string
+	OfflineMode bool
+
+	// For Gitea
+	InsecureSkipTLS bool
+}
+
+// CloneIfRequired ...
+func CloneIfRequired(ctx context.Context, refName plumbing.ReferenceName, input NewGitCloneExecutorInput, logger log.FieldLogger) (*git.Repository, error) {
+	r, err := git.PlainOpen(input.Dir)
+	if err != nil {
+		var progressWriter io.Writer
+		if isatty.IsTerminal(os.Stdout.Fd()) || isatty.IsCygwinTerminal(os.Stdout.Fd()) {
+			if entry, ok := logger.(*log.Entry); ok {
+				progressWriter = entry.WriterLevel(log.DebugLevel)
+			} else if lgr, ok := logger.(*log.Logger); ok {
+				progressWriter = lgr.WriterLevel(log.DebugLevel)
+			} else {
+				log.Errorf("Unable to get writer from logger (type=%T)", logger)
+				progressWriter = os.Stdout
+			}
+		}
+
+		cloneOptions := git.CloneOptions{
+			URL:      input.URL,
+			Progress: progressWriter,
+
+			InsecureSkipTLS: input.InsecureSkipTLS, // For Gitea
+		}
+		if input.Token != "" {
+			cloneOptions.Auth = &http.BasicAuth{
+				Username: "token",
+				Password: input.Token,
+			}
+		}
+
+		r, err = git.PlainCloneContext(ctx, input.Dir, false, &cloneOptions)
+		if err != nil {
+			logger.Errorf("Unable to clone %v %s: %v", input.URL, refName, err)
+			return nil, err
+		}
+
+		if err = os.Chmod(input.Dir, 0o755); err != nil {
+			return nil, err
+		}
+	}
+
+	return r, nil
+}
+
+func gitOptions(token string) (fetchOptions git.FetchOptions, pullOptions git.PullOptions) {
+	fetchOptions.RefSpecs = []config.RefSpec{"refs/*:refs/*", "HEAD:refs/heads/HEAD"}
+	pullOptions.Force = true
+
+	if token != "" {
+		auth := &http.BasicAuth{
+			Username: "token",
+			Password: token,
+		}
+		fetchOptions.Auth = auth
+		pullOptions.Auth = auth
+	}
+
+	return fetchOptions, pullOptions
+}
+
+// NewGitCloneExecutor creates an executor to clone git repos
+//
+//nolint:gocyclo
+func NewGitCloneExecutor(input NewGitCloneExecutorInput) common.Executor {
+	return func(ctx context.Context) error {
+		logger := common.Logger(ctx)
+		logger.Infof("  \u2601  git clone '%s' # ref=%s", input.URL, input.Ref)
+		logger.Debugf("  cloning %s to %s", input.URL, input.Dir)
+
+		cloneLock.Lock()
+		defer cloneLock.Unlock()
+
+		refName := plumbing.ReferenceName(fmt.Sprintf("refs/heads/%s", input.Ref))
+		r, err := CloneIfRequired(ctx, refName, input, logger)
+		if err != nil {
+			return err
+		}
+
+		isOfflineMode := input.OfflineMode
+
+		// fetch latest changes
+		fetchOptions, pullOptions := gitOptions(input.Token)
+
+		if input.InsecureSkipTLS { // For Gitea
+			fetchOptions.InsecureSkipTLS = true
+			pullOptions.InsecureSkipTLS = true
+		}
+
+		if !isOfflineMode {
+			err = r.Fetch(&fetchOptions)
+			if err != nil && !errors.Is(err, git.NoErrAlreadyUpToDate) {
+				return err
+			}
+		}
+
+		var hash *plumbing.Hash
+		rev := plumbing.Revision(input.Ref)
+		if hash, err = r.ResolveRevision(rev); err != nil {
+			logger.Errorf("Unable to resolve %s: %v", input.Ref, err)
+		}
+
+		if hash.String() != input.Ref && strings.HasPrefix(hash.String(), input.Ref) {
+			return &Error{
+				err:    ErrShortRef,
+				commit: hash.String(),
+			}
+		}
+
+		// At this point we need to know if it's a tag or a branch
+		// And the easiest way to do it is duck typing
+		//
+		// If err is nil, it's a tag so let's proceed with that hash like we would if
+		// it was a sha
+		refType := "tag"
+		rev = plumbing.Revision(path.Join("refs", "tags", input.Ref))
+		if _, err := r.Tag(input.Ref); errors.Is(err, git.ErrTagNotFound) {
+			rName := plumbing.ReferenceName(path.Join("refs", "remotes", "origin", input.Ref))
+			if _, err := r.Reference(rName, false); errors.Is(err, plumbing.ErrReferenceNotFound) {
+				refType = "sha"
+				rev = plumbing.Revision(input.Ref)
+			} else {
+				refType = "branch"
+				rev = plumbing.Revision(rName)
+			}
+		}
+
+		if hash, err = r.ResolveRevision(rev); err != nil {
+			logger.Errorf("Unable to resolve %s: %v", input.Ref, err)
+			return err
+		}
+
+		var w *git.Worktree
+		if w, err = r.Worktree(); err != nil {
+			return err
+		}
+
+		// If the hash resolved doesn't match the ref provided in a workflow then we're
+		// using a branch or tag ref, not a sha
+		//
+		// Repos on disk point to commit hashes, and need to checkout input.Ref before
+		// we try and pull down any changes
+		if hash.String() != input.Ref && refType == "branch" {
+			logger.Debugf("Provided ref is not a sha. Checking out branch before pulling changes")
+			sourceRef := plumbing.ReferenceName(path.Join("refs", "remotes", "origin", input.Ref))
+			if err = w.Checkout(&git.CheckoutOptions{
+				Branch: sourceRef,
+				Force:  true,
+			}); err != nil {
+				logger.Errorf("Unable to checkout %s: %v", sourceRef, err)
+				return err
+			}
+		}
+		if !isOfflineMode {
+			if err = w.Pull(&pullOptions); err != nil && err != git.NoErrAlreadyUpToDate {
+				logger.Debugf("Unable to pull %s: %v", refName, err)
+			}
+		}
+		logger.Debugf("Cloned %s to %s", input.URL, input.Dir)
+
+		if hash.String() != input.Ref && refType == "branch" {
+			logger.Debugf("Provided ref is not a sha. Updating branch ref after pull")
+			if hash, err = r.ResolveRevision(rev); err != nil {
+				logger.Errorf("Unable to resolve %s: %v", input.Ref, err)
+				return err
+			}
+		}
+		if err = w.Checkout(&git.CheckoutOptions{
+			Hash:  *hash,
+			Force: true,
+		}); err != nil {
+			logger.Errorf("Unable to checkout %s: %v", *hash, err)
+			return err
+		}
+
+		if err = w.Reset(&git.ResetOptions{
+			Mode:   git.HardReset,
+			Commit: *hash,
+		}); err != nil {
+			logger.Errorf("Unable to reset to %s: %v", hash.String(), err)
+			return err
+		}
+
+		logger.Debugf("Checked out %s", input.Ref)
+		return nil
+	}
+}
diff --git a/pkg/common/git/git_test.go b/pkg/common/git/git_test.go
new file mode 100644
index 0000000..6ad66b6
--- /dev/null
+++ b/pkg/common/git/git_test.go
@@ -0,0 +1,249 @@
+package git
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"syscall"
+	"testing"
+
+	log "github.com/sirupsen/logrus"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestFindGitSlug(t *testing.T) {
+	assert := assert.New(t)
+
+	var slugTests = []struct {
+		url      string // input
+		provider string // expected result
+		slug     string // expected result
+	}{
+		{"https://git-codecommit.us-east-1.amazonaws.com/v1/repos/my-repo-name", "CodeCommit", "my-repo-name"},
+		{"ssh://git-codecommit.us-west-2.amazonaws.com/v1/repos/my-repo", "CodeCommit", "my-repo"},
+		{"git@github.com:nektos/act.git", "GitHub", "nektos/act"},
+		{"git@github.com:nektos/act", "GitHub", "nektos/act"},
+		{"https://github.com/nektos/act.git", "GitHub", "nektos/act"},
+		{"http://github.com/nektos/act.git", "GitHub", "nektos/act"},
+		{"https://github.com/nektos/act", "GitHub", "nektos/act"},
+		{"http://github.com/nektos/act", "GitHub", "nektos/act"},
+		{"git+ssh://git@github.com/owner/repo.git", "GitHub", "owner/repo"},
+		{"http://myotherrepo.com/act.git", "", "http://myotherrepo.com/act.git"},
+	}
+
+	for _, tt := range slugTests {
+		provider, slug, err := findGitSlug(tt.url, "github.com")
+
+		assert.NoError(err)
+		assert.Equal(tt.provider, provider)
+		assert.Equal(tt.slug, slug)
+	}
+}
+
+func testDir(t *testing.T) string {
+	basedir, err := os.MkdirTemp("", "act-test")
+	require.NoError(t, err)
+	t.Cleanup(func() { _ = os.RemoveAll(basedir) })
+	return basedir
+}
+
+func cleanGitHooks(dir string) error {
+	hooksDir := filepath.Join(dir, ".git", "hooks")
+	files, err := os.ReadDir(hooksDir)
+	if err != nil {
+		if os.IsNotExist(err) {
+			return nil
+		}
+		return err
+	}
+	for _, f := range files {
+		if f.IsDir() {
+			continue
+		}
+		relName := filepath.Join(hooksDir, f.Name())
+		if err := os.Remove(relName); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func TestFindGitRemoteURL(t *testing.T) {
+	assert := assert.New(t)
+
+	basedir := testDir(t)
+	gitConfig()
+	err := gitCmd("init", basedir)
+	assert.NoError(err)
+	err = cleanGitHooks(basedir)
+	assert.NoError(err)
+
+	remoteURL := "https://git-codecommit.us-east-1.amazonaws.com/v1/repos/my-repo-name"
+	err = gitCmd("-C", basedir, "remote", "add", "origin", remoteURL)
+	assert.NoError(err)
+
+	u, err := findGitRemoteURL(context.Background(), basedir, "origin")
+	assert.NoError(err)
+	assert.Equal(remoteURL, u)
+
+	remoteURL = "git@github.com/AwesomeOwner/MyAwesomeRepo.git"
+	err = gitCmd("-C", basedir, "remote", "add", "upstream", remoteURL)
+	assert.NoError(err)
+	u, err = findGitRemoteURL(context.Background(), basedir, "upstream")
+	assert.NoError(err)
+	assert.Equal(remoteURL, u)
+}
+
+func TestGitFindRef(t *testing.T) {
+	basedir := testDir(t)
+	gitConfig()
+
+	for name, tt := range map[string]struct {
+		Prepare func(t *testing.T, dir string)
+		Assert  func(t *testing.T, ref string, err error)
+	}{
+		"new_repo": {
+			Prepare: func(t *testing.T, dir string) {},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.Error(t, err)
+			},
+		},
+		"new_repo_with_commit": {
+			Prepare: func(t *testing.T, dir string) {
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "msg"))
+			},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.NoError(t, err)
+				require.Equal(t, "refs/heads/master", ref)
+			},
+		},
+		"current_head_is_tag": {
+			Prepare: func(t *testing.T, dir string) {
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "commit msg"))
+				require.NoError(t, gitCmd("-C", dir, "tag", "v1.2.3"))
+				require.NoError(t, gitCmd("-C", dir, "checkout", "v1.2.3"))
+			},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.NoError(t, err)
+				require.Equal(t, "refs/tags/v1.2.3", ref)
+			},
+		},
+		"current_head_is_same_as_tag": {
+			Prepare: func(t *testing.T, dir string) {
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "1.4.2 release"))
+				require.NoError(t, gitCmd("-C", dir, "tag", "v1.4.2"))
+			},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.NoError(t, err)
+				require.Equal(t, "refs/tags/v1.4.2", ref)
+			},
+		},
+		"current_head_is_not_tag": {
+			Prepare: func(t *testing.T, dir string) {
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "msg"))
+				require.NoError(t, gitCmd("-C", dir, "tag", "v1.4.2"))
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "msg2"))
+			},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.NoError(t, err)
+				require.Equal(t, "refs/heads/master", ref)
+			},
+		},
+		"current_head_is_another_branch": {
+			Prepare: func(t *testing.T, dir string) {
+				require.NoError(t, gitCmd("-C", dir, "checkout", "-b", "mybranch"))
+				require.NoError(t, gitCmd("-C", dir, "commit", "--allow-empty", "-m", "msg"))
+			},
+			Assert: func(t *testing.T, ref string, err error) {
+				require.NoError(t, err)
+				require.Equal(t, "refs/heads/mybranch", ref)
+			},
+		},
+	} {
+		tt := tt
+		name := name
+		t.Run(name, func(t *testing.T) {
+			dir := filepath.Join(basedir, name)
+			require.NoError(t, os.MkdirAll(dir, 0o755))
+			require.NoError(t, gitCmd("-C", dir, "init", "--initial-branch=master"))
+			require.NoError(t, cleanGitHooks(dir))
+			tt.Prepare(t, dir)
+			ref, err := FindGitRef(context.Background(), dir)
+			tt.Assert(t, ref, err)
+		})
+	}
+}
+
+func TestGitCloneExecutor(t *testing.T) {
+	for name, tt := range map[string]struct {
+		Err      error
+		URL, Ref string
+	}{
+		"tag": {
+			Err: nil,
+			URL: "https://github.com/actions/checkout",
+			Ref: "v2",
+		},
+		"branch": {
+			Err: nil,
+			URL: "https://github.com/anchore/scan-action",
+			Ref: "act-fails",
+		},
+		"sha": {
+			Err: nil,
+			URL: "https://github.com/actions/checkout",
+			Ref: "5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f", // v2
+		},
+		"short-sha": {
+			Err: &Error{ErrShortRef, "5a4ac9002d0be2fb38bd78e4b4dbde5606d7042f"},
+			URL: "https://github.com/actions/checkout",
+			Ref: "5a4ac90", // v2
+		},
+	} {
+		t.Run(name, func(t *testing.T) {
+			clone := NewGitCloneExecutor(NewGitCloneExecutorInput{
+				URL: tt.URL,
+				Ref: tt.Ref,
+				Dir: testDir(t),
+			})
+
+			err := clone(context.Background())
+			if tt.Err != nil {
+				assert.Error(t, err)
+				assert.Equal(t, tt.Err, err)
+			} else {
+				assert.Empty(t, err)
+			}
+		})
+	}
+}
+
+func gitConfig() {
+	if os.Getenv("GITHUB_ACTIONS") == "true" {
+		var err error
+		if err = gitCmd("config", "--global", "user.email", "test@test.com"); err != nil {
+			log.Error(err)
+		}
+		if err = gitCmd("config", "--global", "user.name", "Unit Test"); err != nil {
+			log.Error(err)
+		}
+	}
+}
+
+func gitCmd(args ...string) error {
+	cmd := exec.Command("git", args...)
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+
+	err := cmd.Run()
+	if exitError, ok := err.(*exec.ExitError); ok {
+		if waitStatus, ok := exitError.Sys().(syscall.WaitStatus); ok {
+			return fmt.Errorf("Exit error %d", waitStatus.ExitStatus())
+		}
+		return exitError
+	}
+	return nil
+}
diff --git a/pkg/common/job_error.go b/pkg/common/job_error.go
new file mode 100644
index 0000000..334c6ca
--- /dev/null
+++ b/pkg/common/job_error.go
@@ -0,0 +1,30 @@
+package common
+
+import (
+	"context"
+)
+
+type jobErrorContextKey string
+
+const jobErrorContextKeyVal = jobErrorContextKey("job.error")
+
+// JobError returns the job error for current context if any
+func JobError(ctx context.Context) error {
+	val := ctx.Value(jobErrorContextKeyVal)
+	if val != nil {
+		if container, ok := val.(map[string]error); ok {
+			return container["error"]
+		}
+	}
+	return nil
+}
+
+func SetJobError(ctx context.Context, err error) {
+	ctx.Value(jobErrorContextKeyVal).(map[string]error)["error"] = err
+}
+
+// WithJobErrorContainer adds a value to the context as a container for an error
+func WithJobErrorContainer(ctx context.Context) context.Context {
+	container := map[string]error{}
+	return context.WithValue(ctx, jobErrorContextKeyVal, container)
+}
diff --git a/pkg/common/line_writer.go b/pkg/common/line_writer.go
new file mode 100644
index 0000000..2035199
--- /dev/null
+++ b/pkg/common/line_writer.go
@@ -0,0 +1,50 @@
+package common
+
+import (
+	"bytes"
+	"io"
+)
+
+// LineHandler is a callback function for handling a line
+type LineHandler func(line string) bool
+
+type lineWriter struct {
+	buffer   bytes.Buffer
+	handlers []LineHandler
+}
+
+// NewLineWriter creates a new instance of a line writer
+func NewLineWriter(handlers ...LineHandler) io.Writer {
+	w := new(lineWriter)
+	w.handlers = handlers
+	return w
+}
+
+func (lw *lineWriter) Write(p []byte) (n int, err error) {
+	pBuf := bytes.NewBuffer(p)
+	written := 0
+	for {
+		line, err := pBuf.ReadString('\n')
+		w, _ := lw.buffer.WriteString(line)
+		written += w
+		if err == nil {
+			lw.handleLine(lw.buffer.String())
+			lw.buffer.Reset()
+		} else if err == io.EOF {
+			break
+		} else {
+			return written, err
+		}
+	}
+
+	return written, nil
+}
+
+func (lw *lineWriter) handleLine(line string) {
+	for _, h := range lw.handlers {
+		ok := h(line)
+		if !ok {
+			break
+		}
+	}
+}
diff --git a/pkg/common/line_writer_test.go b/pkg/common/line_writer_test.go
new file mode 100644
index 0000000..44e11ef
--- /dev/null
+++ b/pkg/common/line_writer_test.go
@@ -0,0 +1,37 @@
+package common
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestLineWriter(t *testing.T) {
+	lines := make([]string, 0)
+	lineHandler := func(s string) bool {
+		lines = append(lines, s)
+		return true
+	}
+
+	lineWriter := NewLineWriter(lineHandler)
+
+	assert := assert.New(t)
+	write := func(s string) {
+		n, err := lineWriter.Write([]byte(s))
+		assert.NoError(err)
+		assert.Equal(len(s), n, s)
+	}
+
+	write("hello")
+	write(" ")
+	write("world!!\nextra")
+	write(" line\n and another\nlast")
+	write(" line\n")
+	write("no newline here...")
+
+	assert.Len(lines, 4)
+	assert.Equal("hello world!!\n", lines[0])
+	assert.Equal("extra line\n", lines[1])
+	assert.Equal(" and another\n", lines[2])
+	assert.Equal("last line\n", lines[3])
+}
diff --git a/pkg/common/logger.go b/pkg/common/logger.go
new file mode 100644
index 0000000..74fc96d
--- /dev/null
+++ b/pkg/common/logger.go
@@ -0,0 +1,48 @@
+package common
+
+import (
+	"context"
+
+	"github.com/sirupsen/logrus"
+)
+
+type loggerContextKey string
+
+const loggerContextKeyVal = loggerContextKey("logrus.FieldLogger")
+
+// Logger returns the appropriate logger for current context
+func Logger(ctx context.Context) logrus.FieldLogger {
+	val := ctx.Value(loggerContextKeyVal)
+	if val != nil {
+		if logger, ok := val.(logrus.FieldLogger); ok {
+			return logger
+		}
+	}
+	return logrus.StandardLogger()
+}
+
+// WithLogger adds a value to the context for the logger
+func WithLogger(ctx context.Context, logger logrus.FieldLogger) context.Context {
+	return context.WithValue(ctx, loggerContextKeyVal, logger)
+}
+
+type loggerHookKey string
+
+const loggerHookKeyVal = loggerHookKey("logrus.Hook")
+
+// LoggerHook returns the appropriate logger hook for current context
+// the hook affects job logger, not global logger
+func LoggerHook(ctx context.Context) logrus.Hook {
+	val := ctx.Value(loggerHookKeyVal)
+	if val != nil {
+		if hook, ok := val.(logrus.Hook); ok {
+			return hook
+		}
+	}
+	return nil
+}
+
+// WithLoggerHook adds a value to the context for the logger hook
+func WithLoggerHook(ctx context.Context, hook logrus.Hook) context.Context {
+	return context.WithValue(ctx, loggerHookKeyVal, hook)
+}
diff --git a/pkg/common/outbound_ip.go b/pkg/common/outbound_ip.go
new file mode 100644
index 0000000..66e15e5
--- /dev/null
+++ b/pkg/common/outbound_ip.go
@@ -0,0 +1,75 @@
+package common
+
+import (
+	"net"
+	"sort"
+	"strings"
+)
+
+// GetOutboundIP returns an outbound IP address of this machine.
+// It tries to access the internet and returns the local IP address of the connection.
+// If the machine cannot access the internet, it returns a preferred IP address from network interfaces.
+// It returns nil if no IP address is found.
+func GetOutboundIP() net.IP {
+	// See https://stackoverflow.com/a/37382208
+	conn, err := net.Dial("udp", "8.8.8.8:80")
+	if err == nil {
+		defer conn.Close()
+		return conn.LocalAddr().(*net.UDPAddr).IP
+	}
+
+	// So the machine cannot access the internet. Pick an IP address from network interfaces.
+	if ifs, err := net.Interfaces(); err == nil {
+		type IP struct {
+			net.IP
+			net.Interface
+		}
+		var ips []IP
+		for _, i := range ifs {
+			if addrs, err := i.Addrs(); err == nil {
+				for _, addr := range addrs {
+					var ip net.IP
+					switch v := addr.(type) {
+					case *net.IPNet:
+						ip = v.IP
+					case *net.IPAddr:
+						ip = v.IP
+					}
+					if ip.IsGlobalUnicast() {
+						ips = append(ips, IP{ip, i})
+					}
+				}
+			}
+		}
+		if len(ips) > 1 {
+			sort.Slice(ips, func(i, j int) bool {
+				ifi := ips[i].Interface
+				ifj := ips[j].Interface
+
+				// ethernet is preferred
+				if vi, vj := strings.HasPrefix(ifi.Name, "e"), strings.HasPrefix(ifj.Name, "e"); vi != vj {
+					return vi
+				}
+
+				ipi := ips[i].IP
+				ipj := ips[j].IP
+
+				// IPv4 is preferred
+				if vi, vj := ipi.To4() != nil, ipj.To4() != nil; vi != vj {
+					return vi
+				}
+
+				// en0 is preferred to en1
+				if ifi.Name != ifj.Name {
+					return ifi.Name < ifj.Name
+				}
+
+				// fallback
+				return ipi.String() < ipj.String()
+			})
+			return ips[0].IP
+		}
+	}
+
+	return nil
+}