packer: Prepare provisioners as part of Build prepare

packer/build.go

@@ -39,12 +39,21 @@ func (b *coreBuild) Name() string {
 // Prepare prepares the build by doing some initialization for the builder
 // and any hooks. This _must_ be called prior to Run.
 func (b *coreBuild) Prepare(ui Ui) (err error) {
+	// TODO: lock
 	b.prepareCalled = true
+
+	// Prepare the builder
 	err = b.builder.Prepare(b.builderConfig)
 	if err != nil {
 		log.Printf("Build '%s' prepare failure: %s\n", b.name, err)
 	}
 
+	// Prepare the provisioners
+	// TODO: error handling
+	for _, coreProv := range b.provisioners {
+		coreProv.provisioner.Prepare(coreProv.config, ui)
+	}
+
 	return
 }
 

packer/build_test.go

@@ -31,6 +31,9 @@ func testBuild() Build {
 		name:          "test",
 		builder:       &TestBuilder{},
 		builderConfig: 42,
+		provisioners: []coreBuildProvisioner{
+			coreBuildProvisioner{&TestProvisioner{}, 42},
+		},
 	}
 }
 
@@ -65,10 +68,19 @@ func TestBuild_Run(t *testing.T) {
 	build.Prepare(ui)
 	build.Run(ui)
 
-	builder := build.(*coreBuild).builder.(*TestBuilder)
+	coreB := build.(*coreBuild)
 
+	// Verify builder was prepared
+	builder := coreB.builder.(*TestBuilder)
 	assert.True(builder.runCalled, "run should be called")
 	assert.Equal(builder.runUi, ui, "run should be called with ui")
+
+	// Verify provisioners were prepared
+	coreProv := coreB.provisioners[0]
+	prov := coreProv.provisioner.(*TestProvisioner)
+	assert.True(prov.prepCalled, "prepare should be called")
+	assert.Equal(prov.prepConfig, 42, "prepare should be called with proper config")
+	assert.Equal(prov.prepUi, ui, "prepare should be called with proper ui")
 }
 
 func TestBuild_RunBeforePrepare(t *testing.T) {

packer/provisioner_test.go

@@ -2,11 +2,15 @@ package packer
 
 type TestProvisioner struct {
 	prepCalled bool
+	prepConfig interface{}
+	prepUi     Ui
 	provCalled bool
 }
 
-func (t *TestProvisioner) Prepare(interface{}, Ui) {
+func (t *TestProvisioner) Prepare(config interface{}, ui Ui) {
 	t.prepCalled = true
+	t.prepConfig = config
+	t.prepUi = ui
 }
 
 func (t *TestProvisioner) Provision(Ui, Communicator) {

packer/rpc/build_test.go

@@ -12,7 +12,7 @@ var testBuildArtifact = &testArtifact{}
 type testBuild struct {
 	nameCalled    bool
 	prepareCalled bool
-	prepareUi packer.Ui
+	prepareUi     packer.Ui
 	runCalled     bool
 	runUi         packer.Ui
 }