HCL2 variables: split validation from getting value (#10843)

* HCL2 variables: split validation from getting value, to only

This way we do this only once and log this only once. The errors were being ignored anyways.

* Update types.variables_test.go

hcl2template/parser.go

@@ -290,7 +290,7 @@ func filterVarsFromLogs(inputOrLocal Variables) {
 		if !variable.Sensitive {
 			continue
 		}
-		value, _ := variable.Value()
+		value := variable.Value()
 		_ = cty.Walk(value, func(_ cty.Path, nested cty.Value) (bool, error) {
 			if nested.IsWhollyKnown() && !nested.IsNull() && nested.Type().Equals(cty.String) {
 				packersdk.LogSecretFilter.Set(nested.AsString())
@@ -310,9 +310,9 @@ func (cfg *PackerConfig) Initialize(opts packer.InitializeOptions) hcl.Diagnosti
 		return diags
 	}
 
-	_, moreDiags = cfg.InputVariables.Values()
+	moreDiags = cfg.InputVariables.ValidateValues()
 	diags = append(diags, moreDiags...)
-	_, moreDiags = cfg.LocalVariables.Values()
+	moreDiags = cfg.LocalVariables.ValidateValues()
 	diags = append(diags, moreDiags...)
 	diags = append(diags, cfg.evaluateDatasources(opts.SkipDatasourcesExecution)...)
 	diags = append(diags, cfg.evaluateLocalVariables(cfg.LocalBlocks)...)

hcl2template/types.packer_config.go

@@ -91,8 +91,8 @@ const (
 // decoder in order to tell what is the actual value of a var or a local and
 // the list of defined functions.
 func (cfg *PackerConfig) EvalContext(ctx BlockContext, variables map[string]cty.Value) *hcl.EvalContext {
-	inputVariables, _ := cfg.InputVariables.Values()
-	localVariables, _ := cfg.LocalVariables.Values()
+	inputVariables := cfg.InputVariables.Values()
+	localVariables := cfg.LocalVariables.Values()
 	ectx := &hcl.EvalContext{
 		Functions: Functions(cfg.Basedir),
 		Variables: map[string]cty.Value{
@@ -594,7 +594,7 @@ func (p *PackerConfig) printVariables() string {
 	sort.Strings(keys)
 	for _, key := range keys {
 		v := p.InputVariables[key]
-		val, _ := v.Value()
+		val := v.Value()
 		fmt.Fprintf(out, "var.%s: %q\n", v.Name, PrintableCtyValue(val))
 	}
 	out.WriteString("\n> local-variables:\n\n")
@@ -602,7 +602,7 @@ func (p *PackerConfig) printVariables() string {
 	sort.Strings(keys)
 	for _, key := range keys {
 		v := p.LocalVariables[key]
-		val, _ := v.Value()
+		val := v.Value()
 		fmt.Fprintf(out, "local.%s: %q\n", v.Name, PrintableCtyValue(val))
 	}
 	return out.String()

hcl2template/types.variables.go

@@ -152,9 +152,19 @@ func (v *Variable) validateValue(val VariableAssignment) (diags hcl.Diagnostics)
 }
 
 // Value returns the last found value from the list of variable settings.
-func (v *Variable) Value() (cty.Value, hcl.Diagnostics) {
+func (v *Variable) Value() cty.Value {
 	if len(v.Values) == 0 {
-		return cty.UnknownVal(v.Type), hcl.Diagnostics{&hcl.Diagnostic{
+		return cty.UnknownVal(v.Type)
+	}
+	val := v.Values[len(v.Values)-1]
+	return val.Value
+}
+
+// ValidateValue tells if the selected value for the Variable is valid according
+// to its validation settings.
+func (v *Variable) ValidateValue() hcl.Diagnostics {
+	if len(v.Values) == 0 {
+		return hcl.Diagnostics{&hcl.Diagnostic{
 			Severity: hcl.DiagError,
 			Summary:  fmt.Sprintf("Unset variable %q", v.Name),
 			Detail: "A used variable must be set or have a default value; see " +
@@ -163,8 +173,8 @@ func (v *Variable) Value() (cty.Value, hcl.Diagnostics) {
 			Context: v.Range.Ptr(),
 		}}
 	}
-	val := v.Values[len(v.Values)-1]
-	return val.Value, v.validateValue(v.Values[len(v.Values)-1])
+
+	return v.validateValue(v.Values[len(v.Values)-1])
 }
 
 type Variables map[string]*Variable
@@ -177,15 +187,21 @@ func (variables Variables) Keys() []string {
 	return keys
 }
 
-func (variables Variables) Values() (map[string]cty.Value, hcl.Diagnostics) {
+func (variables Variables) Values() map[string]cty.Value {
 	res := map[string]cty.Value{}
-	var diags hcl.Diagnostics
 	for k, v := range variables {
-		value, moreDiags := v.Value()
-		diags = append(diags, moreDiags...)
+		value := v.Value()
 		res[k] = value
 	}
-	return res, diags
+	return res
+}
+
+func (variables Variables) ValidateValues() hcl.Diagnostics {
+	var diags hcl.Diagnostics
+	for _, v := range variables {
+		diags = append(diags, v.ValidateValue()...)
+	}
+	return diags
 }
 
 // decodeVariable decodes a variable key and value into Variables

hcl2template/types.variables_test.go

@@ -868,7 +868,7 @@ func TestVariables_collectVariableValues(t *testing.T) {
 			}
 			values := map[string]cty.Value{}
 			for k, v := range tt.variables {
-				value, diag := v.Value()
+				value, diag := v.Value(), v.ValidateValue()
 				if diag != nil {
 					t.Fatalf("Value %s: %v", k, diag)
 				}