Merge pull request #7733 from hashicorp/fix_var_recurisve_itnerpolation

fixing interpolation

packer/core.go

@@ -306,7 +306,6 @@ func (c *Core) init() error {
 	if c.variables == nil {
 		c.variables = make(map[string]string)
 	}
-
 	// Go through the variables and interpolate the environment and
 	// user variables
 
@@ -314,7 +313,6 @@ func (c *Core) init() error {
 	ctx.EnableEnv = true
 	ctx.UserVariables = make(map[string]string)
 	shouldRetry := true
-	tryCount := 0
 	changed := false
 	failedInterpolation := ""
 
@@ -337,32 +335,40 @@ func (c *Core) init() error {
 	// interpolating them.  Please don't actually nest your variables in 100
 	// layers of other variables. Please.
 
-	for shouldRetry == true {
-		shouldRetry = false
+	// c.Template.Variables is populated by variables defined within the Template
+	// itself
+	// c.variables is populated by variables read in from the command line and
+	// var-files.
+	// We need to read the keys from both, then loop over all of them to figure
+	// out the appropriate interpolations.
+
+	allVariables := make(map[string]string)
+	// load in template variables
 	for k, v := range c.Template.Variables {
-			// Ignore variables that are required
-			if v.Required {
-				continue
+		allVariables[k] = v.Default
 	}
 
-			// Ignore variables that have a value already
-			if _, ok := c.variables[k]; ok {
-				continue
+	// overwrite template variables with command-line-read variables
+	for k, v := range c.variables {
+		allVariables[k] = v
 	}
 
+	for i := 0; i < 100; i++ {
+		shouldRetry = false
+		// First, loop over the variables in the template
+		for k, v := range allVariables {
 			// Interpolate the default
-			def, err := interpolate.Render(v.Default, ctx)
+			renderedV, err := interpolate.Render(v, ctx)
 			switch err.(type) {
 			case nil:
 				// We only get here if interpolation has succeeded, so something is
 				// different in this loop than in the last one.
 				changed = true
-				c.variables[k] = def
+				c.variables[k] = renderedV
 				ctx.UserVariables = c.variables
 			case ttmp.ExecError:
 				shouldRetry = true
-				tryCount++
-				failedInterpolation = fmt.Sprintf(`"%s": "%s"`, k, v.Default)
+				failedInterpolation = fmt.Sprintf(`"%s": "%s"`, k, v)
 				continue
 			default:
 				return fmt.Errorf(
@@ -371,10 +377,9 @@ func (c *Core) init() error {
 					k, err)
 			}
 		}
-		if tryCount >= 100 {
+		if !shouldRetry {
 			break
 		}
-
 	}
 
 	if (changed == false) && (shouldRetry == true) {
@@ -385,13 +390,8 @@ func (c *Core) init() error {
 	}
 
 	for _, v := range c.Template.SensitiveVariables {
-		def, err := interpolate.Render(v.Default, ctx)
-		if err != nil {
-			return fmt.Errorf(
-				"error interpolating default value for '%#v': %s",
-				v, err)
-		}
-		c.secrets = append(c.secrets, def)
+		secret := ctx.UserVariables[v.Key]
+		c.secrets = append(c.secrets, secret)
 	}
 
 	// Interpolate the push configuration

packer/core_test.go

@@ -524,6 +524,8 @@ func TestCoreValidate(t *testing.T) {
 	}
 }
 
+// Tests that we can properly interpolate user variables defined within the
+// packer template
 func TestCore_InterpolateUserVars(t *testing.T) {
 	cases := []struct {
 		File     string
@@ -531,7 +533,7 @@ func TestCore_InterpolateUserVars(t *testing.T) {
 		Err      bool
 	}{
 		{
-			"variables.json",
+			"build-variables-interpolate.json",
 			map[string]string{
 				"foo":  "bar",
 				"bar":  "bar",
@@ -541,7 +543,7 @@ func TestCore_InterpolateUserVars(t *testing.T) {
 			false,
 		},
 		{
-			"variables2.json",
+			"build-variables-interpolate2.json",
 			map[string]string{},
 			true,
 		},
@@ -576,6 +578,74 @@ func TestCore_InterpolateUserVars(t *testing.T) {
 	}
 }
 
+// Tests that we can properly interpolate user variables defined within a
+// var-file provided alongside the Packer template
+func TestCore_InterpolateUserVars_VarFile(t *testing.T) {
+	cases := []struct {
+		File      string
+		Variables map[string]string
+		Expected  map[string]string
+		Err       bool
+	}{
+		{
+			// tests that we can interpolate from var files when var isn't set in
+			// originating template
+			"build-basic-interpolated.json",
+			map[string]string{
+				"name":   "gotta-{{user `my_var`}}",
+				"my_var": "interpolate-em-all",
+			},
+			map[string]string{
+				"name":   "gotta-interpolate-em-all",
+				"my_var": "interpolate-em-all"},
+			false,
+		},
+		{
+			// tests that we can interpolate from var files when var is set in
+			// originating template as required
+			"build-basic-interpolated-required.json",
+			map[string]string{
+				"name":   "gotta-{{user `my_var`}}",
+				"my_var": "interpolate-em-all",
+			},
+			map[string]string{
+				"name":   "gotta-interpolate-em-all",
+				"my_var": "interpolate-em-all"},
+			false,
+		},
+	}
+	for _, tc := range cases {
+		f, err := os.Open(fixtureDir(tc.File))
+		if err != nil {
+			t.Fatalf("err: %s", err)
+		}
+
+		tpl, err := template.Parse(f)
+		f.Close()
+		if err != nil {
+			t.Fatalf("err: %s\n\n%s", tc.File, err)
+		}
+
+		ccf, err := NewCore(&CoreConfig{
+			Template:  tpl,
+			Version:   "1.0.0",
+			Variables: tc.Variables,
+		})
+
+		if (err != nil) != tc.Err {
+			t.Fatalf("err: %s\n\n%s", tc.File, err)
+		}
+		if !tc.Err {
+			for k, v := range ccf.variables {
+				if tc.Expected[k] != v {
+					t.Fatalf("Expected value %s for key %s but got %s",
+						tc.Expected[k], k, v)
+				}
+			}
+		}
+	}
+}
+
 func TestSensitiveVars(t *testing.T) {
 	cases := []struct {
 		File          string
@@ -595,9 +665,10 @@ func TestSensitiveVars(t *testing.T) {
 		// interpolated
 		{
 			"sensitive-variables.json",
-			map[string]string{"foo": "{{build_name}}"},
-			[]string{"foo"},
-			"test",
+			map[string]string{"foo": "bar",
+				"bang": "{{ user `foo`}}"},
+			[]string{"bang"},
+			"bar",
 			false,
 		},
 	}

packer/test-fixtures/build-basic-interpolated-required.json

@@ -0,0 +1,9 @@
+{
+	"variables": {
+		"name": null
+	},
+    "builders": [{
+        "name": "{{upper `name`}}",
+        "type": "test"
+    }]
+}

packer/test-fixtures/build-var-file-interpolate.json

@@ -0,0 +1,3 @@
+{
+	"name": "{{ user `my_var` }}"
+}

packer/test-fixtures/build-var-file-interpolate2.json

@@ -0,0 +1,3 @@
+{
+	"my_var": "interpolate this, yall"
+}