package configs
import (
"fmt"
"github.com/hashicorp/hcl2/ext/typeexpr"
"github.com/hashicorp/hcl2/gohcl"
"github.com/hashicorp/hcl2/hcl"
"github.com/hashicorp/hcl2/hcl/hclsyntax"
"github.com/zclconf/go-cty/cty"
"github.com/zclconf/go-cty/cty/convert"
"github.com/hashicorp/terraform/addrs"
)
// A consistent detail message for all "not a valid identifier" diagnostics.
const badIdentifierDetail = "A name must start with a letter and may contain only letters, digits, underscores, and dashes."
// Variable represents a "variable" block in a module or file.
type Variable struct {
Name string
Description string
Default cty.Value
Type cty.Type
ParsingMode VariableParsingMode
DescriptionSet bool
DeclRange hcl.Range
}
func decodeVariableBlock(block *hcl.Block, override bool) (*Variable, hcl.Diagnostics) {
v := &Variable{
Name: block.Labels[0],
DeclRange: block.DefRange,
}
// Unless we're building an override, we'll set some defaults
// which we might override with attributes below. We leave these
// as zero-value in the override case so we can recognize whether
// or not they are set when we merge.
if !override {
v.Type = cty.DynamicPseudoType
v.ParsingMode = VariableParseLiteral
}
content, diags := block.Body.Content(variableBlockSchema)
if !hclsyntax.ValidIdentifier(v.Name) {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid variable name",
Detail: badIdentifierDetail,
Subject: &block.LabelRanges[0],
})
}
// Don't allow declaration of variables that would conflict with the
// reserved attribute and block type names in a "module" block, since
// these won't be usable for child modules.
for _, attr := range moduleBlockSchema.Attributes {
if attr.Name == v.Name {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid variable name",
Detail: fmt.Sprintf("The variable name %q is reserved due to its special meaning inside module blocks.", attr.Name),
Subject: &block.LabelRanges[0],
})
}
}
for _, blockS := range moduleBlockSchema.Blocks {
if blockS.Type == v.Name {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid variable name",
Detail: fmt.Sprintf("The variable name %q is reserved due to its special meaning inside module blocks.", blockS.Type),
Subject: &block.LabelRanges[0],
})
}
}
if attr, exists := content.Attributes["description"]; exists {
valDiags := gohcl.DecodeExpression(attr.Expr, nil, &v.Description)
diags = append(diags, valDiags...)
v.DescriptionSet = true
}
if attr, exists := content.Attributes["type"]; exists {
ty, parseMode, tyDiags := decodeVariableType(attr.Expr)
diags = append(diags, tyDiags...)
v.Type = ty
v.ParsingMode = parseMode
}
if attr, exists := content.Attributes["default"]; exists {
val, valDiags := attr.Expr.Value(nil)
diags = append(diags, valDiags...)
// Convert the default to the expected type so we can catch invalid
// defaults early and allow later code to assume validity.
// Note that this depends on us having already processed any "type"
// attribute above.
// However, we can't do this if we're in an override file where
// the type might not be set; we'll catch that during merge.
if v.Type != cty.NilType {
var err error
val, err = convert.Convert(val, v.Type)
if err != nil {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid default value for variable",
Detail: fmt.Sprintf("This default value is not compatible with the variable's type constraint: %s.", err),
Subject: attr.Expr.Range().Ptr(),
})
val = cty.DynamicVal
}
}
v.Default = val
}
return v, diags
}
func decodeVariableType(expr hcl.Expression) (cty.Type, VariableParsingMode, hcl.Diagnostics) {
if exprIsNativeQuotedString(expr) {
// Here we're accepting the pre-0.12 form of variable type argument where
// the string values "string", "list" and "map" are accepted has a hint
// about the type used primarily for deciding how to parse values
// given on the command line and in environment variables.
// Only the native syntax ends up in this codepath; we handle the
// JSON syntax (which is, of course, quoted even in the new format)
// in the normal codepath below.
val, diags := expr.Value(nil)
if diags.HasErrors() {
return cty.DynamicPseudoType, VariableParseHCL, diags
}
str := val.AsString()
switch str {
case "string":
return cty.String, VariableParseLiteral, diags
case "list":
return cty.List(cty.DynamicPseudoType), VariableParseHCL, diags
case "map":
return cty.Map(cty.DynamicPseudoType), VariableParseHCL, diags
default:
return cty.DynamicPseudoType, VariableParseHCL, hcl.Diagnostics{{
Severity: hcl.DiagError,
Summary: "Invalid legacy variable type hint",
Detail: `The legacy variable type hint form, using a quoted string, allows only the values "string", "list", and "map". To provide a full type expression, remove the surrounding quotes and give the type expression directly.`,
Subject: expr.Range().Ptr(),
}}
}
}
// First we'll deal with some shorthand forms that the HCL-level type
// expression parser doesn't include. These both emulate pre-0.12 behavior
// of allowing a list or map of any element type as long as all of the
// elements are consistent. This is the same as list(any) or map(any).
switch hcl.ExprAsKeyword(expr) {
case "list":
return cty.List(cty.DynamicPseudoType), VariableParseHCL, nil
case "map":
return cty.Map(cty.DynamicPseudoType), VariableParseHCL, nil
}
ty, diags := typeexpr.TypeConstraint(expr)
if diags.HasErrors() {
return cty.DynamicPseudoType, VariableParseHCL, diags
}
switch {
case ty.IsPrimitiveType():
// Primitive types use literal parsing.
return ty, VariableParseLiteral, diags
default:
// Everything else uses HCL parsing
return ty, VariableParseHCL, diags
}
}
// VariableParsingMode defines how values of a particular variable given by
// text-only mechanisms (command line arguments and environment variables)
// should be parsed to produce the final value.
type VariableParsingMode rune
// VariableParseLiteral is a variable parsing mode that just takes the given
// string directly as a cty.String value.
const VariableParseLiteral VariableParsingMode = 'L'
// VariableParseHCL is a variable parsing mode that attempts to parse the given
// string as an HCL expression and returns the result.
const VariableParseHCL VariableParsingMode = 'H'
// Parse uses the receiving parsing mode to process the given variable value
// string, returning the result along with any diagnostics.
//
// A VariableParsingMode does not know the expected type of the corresponding
// variable, so it's the caller's responsibility to attempt to convert the
// result to the appropriate type and return to the user any diagnostics that
// conversion may produce.
//
// The given name is used to create a synthetic filename in case any diagnostics
// must be generated about the given string value. This should be the name
// of the root module variable whose value will be populated from the given
// string.
//
// If the returned diagnostics has errors, the returned value may not be
// valid.
func (m VariableParsingMode) Parse(name, value string) (cty.Value, hcl.Diagnostics) {
switch m {
case VariableParseLiteral:
return cty.StringVal(value), nil
case VariableParseHCL:
fakeFilename := fmt.Sprintf("<value for var.%s>", name)
expr, diags := hclsyntax.ParseExpression([]byte(value), fakeFilename, hcl.Pos{Line: 1, Column: 1})
if diags.HasErrors() {
return cty.DynamicVal, diags
}
val, valDiags := expr.Value(nil)
diags = append(diags, valDiags...)
return val, diags
default:
// Should never happen
panic(fmt.Errorf("Parse called on invalid VariableParsingMode %#v", m))
}
}
// Output represents an "output" block in a module or file.
type Output struct {
Name string
Description string
Expr hcl.Expression
DependsOn []hcl.Traversal
Sensitive bool
DescriptionSet bool
SensitiveSet bool
DeclRange hcl.Range
}
func decodeOutputBlock(block *hcl.Block, override bool) (*Output, hcl.Diagnostics) {
o := &Output{
Name: block.Labels[0],
DeclRange: block.DefRange,
}
schema := outputBlockSchema
if override {
schema = schemaForOverrides(schema)
}
content, diags := block.Body.Content(schema)
if !hclsyntax.ValidIdentifier(o.Name) {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid output name",
Detail: badIdentifierDetail,
Subject: &block.LabelRanges[0],
})
}
if attr, exists := content.Attributes["description"]; exists {
valDiags := gohcl.DecodeExpression(attr.Expr, nil, &o.Description)
diags = append(diags, valDiags...)
o.DescriptionSet = true
}
if attr, exists := content.Attributes["value"]; exists {
o.Expr = attr.Expr
}
if attr, exists := content.Attributes["sensitive"]; exists {
valDiags := gohcl.DecodeExpression(attr.Expr, nil, &o.Sensitive)
diags = append(diags, valDiags...)
o.SensitiveSet = true
}
if attr, exists := content.Attributes["depends_on"]; exists {
deps, depsDiags := decodeDependsOn(attr)
diags = append(diags, depsDiags...)
o.DependsOn = append(o.DependsOn, deps...)
}
return o, diags
}
// Local represents a single entry from a "locals" block in a module or file.
// The "locals" block itself is not represented, because it serves only to
// provide context for us to interpret its contents.
type Local struct {
Name string
Expr hcl.Expression
DeclRange hcl.Range
}
func decodeLocalsBlock(block *hcl.Block) ([]*Local, hcl.Diagnostics) {
attrs, diags := block.Body.JustAttributes()
if len(attrs) == 0 {
return nil, diags
}
locals := make([]*Local, 0, len(attrs))
for name, attr := range attrs {
if !hclsyntax.ValidIdentifier(name) {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid local value name",
Detail: badIdentifierDetail,
Subject: &attr.NameRange,
})
}
locals = append(locals, &Local{
Name: name,
Expr: attr.Expr,
DeclRange: attr.Range,
})
}
return locals, diags
}
// Addr returns the address of the local value declared by the receiver,
// relative to its containing module.
func (l *Local) Addr() addrs.LocalValue {
return addrs.LocalValue{
Name: l.Name,
}
}
var variableBlockSchema = &hcl.BodySchema{
Attributes: []hcl.AttributeSchema{
{
Name: "description",
},
{
Name: "default",
},
{
Name: "type",
},
},
}
var outputBlockSchema = &hcl.BodySchema{
Attributes: []hcl.AttributeSchema{
{
Name: "description",
},
{
Name: "value",
Required: true,
},
{
Name: "depends_on",
},
{
Name: "sensitive",
},
},
}
