Merge pull request #4663 from marema31/debug-prompt-provisionner

Debug prompt between provisioner scripts

packer/build.go

@@ -200,10 +200,18 @@ func (b *coreBuild) Run(originalUi Ui, cache Cache) ([]Artifact, error) {
 			if len(p.config) > 0 {
 				pConfig = p.config[0]
 			}
-			hookedProvisioners[i] = &HookedProvisioner{
+			if b.debug {
-				p.provisioner,
+				hookedProvisioners[i] = &HookedProvisioner{
-				pConfig,
+					&DebuggedProvisioner{Provisioner: p.provisioner},
-				p.pType,
+					pConfig,
+					p.pType,
+				}
+			} else {
+				hookedProvisioners[i] = &HookedProvisioner{
+					p.provisioner,
+					pConfig,
+					p.pType,
+				}
 			}
 		}
 

packer/provisioner.go

@@ -2,6 +2,7 @@ package packer
 
 import (
 	"fmt"
+	"log"
 	"sync"
 	"time"
 )
@@ -168,3 +169,90 @@ func (p *PausedProvisioner) Cancel() {
 func (p *PausedProvisioner) provision(result chan<- error, ui Ui, comm Communicator) {
 	result <- p.Provisioner.Provision(ui, comm)
 }
+
+// DebuggedProvisioner is a Provisioner implementation that waits until a key
+// press before the provisioner is actually run.
+type DebuggedProvisioner struct {
+	Provisioner Provisioner
+
+	cancelCh chan struct{}
+	doneCh   chan struct{}
+	lock     sync.Mutex
+}
+
+func (p *DebuggedProvisioner) Prepare(raws ...interface{}) error {
+	return p.Provisioner.Prepare(raws...)
+}
+
+func (p *DebuggedProvisioner) Provision(ui Ui, comm Communicator) error {
+	p.lock.Lock()
+	cancelCh := make(chan struct{})
+	p.cancelCh = cancelCh
+
+	// Setup the done channel, which is trigger when we're done
+	doneCh := make(chan struct{})
+	defer close(doneCh)
+	p.doneCh = doneCh
+	p.lock.Unlock()
+
+	defer func() {
+		p.lock.Lock()
+		defer p.lock.Unlock()
+		if p.cancelCh == cancelCh {
+			p.cancelCh = nil
+		}
+		if p.doneCh == doneCh {
+			p.doneCh = nil
+		}
+	}()
+
+	// Use a select to determine if we get cancelled during the wait
+	message := "Pausing before the next provisioner . Press enter to continue."
+
+	result := make(chan string, 1)
+	go func() {
+		line, err := ui.Ask(message)
+		if err != nil {
+			log.Printf("Error asking for input: %s", err)
+		}
+
+		result <- line
+	}()
+
+	select {
+	case <-result:
+	case <-cancelCh:
+		return nil
+	}
+
+	provDoneCh := make(chan error, 1)
+	go p.provision(provDoneCh, ui, comm)
+
+	select {
+	case err := <-provDoneCh:
+		return err
+	case <-cancelCh:
+		p.Provisioner.Cancel()
+		return <-provDoneCh
+	}
+}
+
+func (p *DebuggedProvisioner) Cancel() {
+	var doneCh chan struct{}
+
+	p.lock.Lock()
+	if p.cancelCh != nil {
+		close(p.cancelCh)
+		p.cancelCh = nil
+	}
+	if p.doneCh != nil {
+		doneCh = p.doneCh
+	}
+	p.lock.Unlock()
+
+	<-doneCh
+}
+
+func (p *DebuggedProvisioner) provision(result chan<- error, ui Ui, comm Communicator) {
+	result <- p.Provisioner.Provision(ui, comm)
+}

packer/provisioner_test.go

@@ -197,3 +197,67 @@ func TestPausedProvisionerCancel(t *testing.T) {
 		t.Fatal("cancel should be called")
 	}
 }
+
+func TestDebuggedProvisioner_impl(t *testing.T) {
+	var _ Provisioner = new(DebuggedProvisioner)
+}
+
+func TestDebuggedProvisionerPrepare(t *testing.T) {
+	mock := new(MockProvisioner)
+	prov := &DebuggedProvisioner{
+		Provisioner: mock,
+	}
+
+	prov.Prepare(42)
+	if !mock.PrepCalled {
+		t.Fatal("prepare should be called")
+	}
+	if mock.PrepConfigs[0] != 42 {
+		t.Fatal("should have proper configs")
+	}
+}
+
+func TestDebuggedProvisionerProvision(t *testing.T) {
+	mock := new(MockProvisioner)
+	prov := &DebuggedProvisioner{
+		Provisioner: mock,
+	}
+
+	ui := testUi()
+	comm := new(MockCommunicator)
+	writeReader(ui, "\n")
+	prov.Provision(ui, comm)
+	if !mock.ProvCalled {
+		t.Fatal("prov should be called")
+	}
+	if mock.ProvUi != ui {
+		t.Fatal("should have proper ui")
+	}
+	if mock.ProvCommunicator != comm {
+		t.Fatal("should have proper comm")
+	}
+}
+
+func TestDebuggedProvisionerCancel(t *testing.T) {
+	mock := new(MockProvisioner)
+	prov := &DebuggedProvisioner{
+		Provisioner: mock,
+	}
+
+	provCh := make(chan struct{})
+	mock.ProvFunc = func() error {
+		close(provCh)
+		time.Sleep(10 * time.Millisecond)
+		return nil
+	}
+
+	// Start provisioning and wait for it to start
+	go prov.Provision(testUi(), new(MockCommunicator))
+	<-provCh
+
+	// Cancel it
+	prov.Cancel()
+	if !mock.CancelCalled {
+		t.Fatal("cancel should be called")
+	}
+}