opentofu/configs/configschema/coerce_value.go
James Bardin 67dbd6d345 don't check MinItems with unknowns in blocks
If a block was defined via "dynamic", there will be only one block value
until the expansion is known. Since we can't detect dynamic blocks at
this point, don't verify MinItems while there are unknown values in the
config.

The decoder spec can also only check for existence of a block, so limit
the check to 0 or 1.
2019-07-27 11:50:28 -07:00

281 lines
8.7 KiB
Go

package configschema
import (
"fmt"
"github.com/zclconf/go-cty/cty"
"github.com/zclconf/go-cty/cty/convert"
)
// CoerceValue attempts to force the given value to conform to the type
// implied by the receiever, while also applying the same validation and
// transformation rules that would be applied by the decoder specification
// returned by method DecoderSpec.
//
// This is useful in situations where a configuration must be derived from
// an already-decoded value. It is always better to decode directly from
// configuration where possible since then source location information is
// still available to produce diagnostics, but in special situations this
// function allows a compatible result to be obtained even if the
// configuration objects are not available.
//
// If the given value cannot be converted to conform to the receiving schema
// then an error is returned describing one of possibly many problems. This
// error may be a cty.PathError indicating a position within the nested
// data structure where the problem applies.
func (b *Block) CoerceValue(in cty.Value) (cty.Value, error) {
var path cty.Path
return b.coerceValue(in, path)
}
func (b *Block) coerceValue(in cty.Value, path cty.Path) (cty.Value, error) {
switch {
case in.IsNull():
return cty.NullVal(b.ImpliedType()), nil
case !in.IsKnown():
return cty.UnknownVal(b.ImpliedType()), nil
}
ty := in.Type()
if !ty.IsObjectType() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("an object is required")
}
for name := range ty.AttributeTypes() {
if _, defined := b.Attributes[name]; defined {
continue
}
if _, defined := b.BlockTypes[name]; defined {
continue
}
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("unexpected attribute %q", name)
}
attrs := make(map[string]cty.Value)
for name, attrS := range b.Attributes {
var val cty.Value
switch {
case ty.HasAttribute(name):
val = in.GetAttr(name)
case attrS.Computed || attrS.Optional:
val = cty.NullVal(attrS.Type)
default:
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("attribute %q is required", name)
}
val, err := attrS.coerceValue(val, append(path, cty.GetAttrStep{Name: name}))
if err != nil {
return cty.UnknownVal(b.ImpliedType()), err
}
attrs[name] = val
}
for typeName, blockS := range b.BlockTypes {
switch blockS.Nesting {
case NestingSingle, NestingGroup:
switch {
case ty.HasAttribute(typeName):
var err error
val := in.GetAttr(typeName)
attrs[typeName], err = blockS.coerceValue(val, append(path, cty.GetAttrStep{Name: typeName}))
if err != nil {
return cty.UnknownVal(b.ImpliedType()), err
}
case blockS.MinItems != 1 && blockS.MaxItems != 1:
if blockS.Nesting == NestingGroup {
attrs[typeName] = blockS.EmptyValue()
} else {
attrs[typeName] = cty.NullVal(blockS.ImpliedType())
}
default:
// We use the word "attribute" here because we're talking about
// the cty sense of that word rather than the HCL sense.
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("attribute %q is required", typeName)
}
case NestingList:
switch {
case ty.HasAttribute(typeName):
coll := in.GetAttr(typeName)
switch {
case coll.IsNull():
attrs[typeName] = cty.NullVal(cty.List(blockS.ImpliedType()))
continue
case !coll.IsKnown():
attrs[typeName] = cty.UnknownVal(cty.List(blockS.ImpliedType()))
continue
}
if !coll.CanIterateElements() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("must be a list")
}
l := coll.LengthInt()
// Assume that if there are unknowns this could have come from
// a dynamic block, and we can't validate MinItems yet.
if l < blockS.MinItems && coll.IsWhollyKnown() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("insufficient items for attribute %q; must have at least %d", typeName, blockS.MinItems)
}
if l > blockS.MaxItems && blockS.MaxItems > 0 {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("too many items for attribute %q; cannot have more than %d", typeName, blockS.MaxItems)
}
if l == 0 {
attrs[typeName] = cty.ListValEmpty(blockS.ImpliedType())
continue
}
elems := make([]cty.Value, 0, l)
{
path = append(path, cty.GetAttrStep{Name: typeName})
for it := coll.ElementIterator(); it.Next(); {
var err error
idx, val := it.Element()
val, err = blockS.coerceValue(val, append(path, cty.IndexStep{Key: idx}))
if err != nil {
return cty.UnknownVal(b.ImpliedType()), err
}
elems = append(elems, val)
}
}
attrs[typeName] = cty.ListVal(elems)
case blockS.MinItems == 0:
attrs[typeName] = cty.ListValEmpty(blockS.ImpliedType())
default:
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("attribute %q is required", typeName)
}
case NestingSet:
switch {
case ty.HasAttribute(typeName):
coll := in.GetAttr(typeName)
switch {
case coll.IsNull():
attrs[typeName] = cty.NullVal(cty.Set(blockS.ImpliedType()))
continue
case !coll.IsKnown():
attrs[typeName] = cty.UnknownVal(cty.Set(blockS.ImpliedType()))
continue
}
if !coll.CanIterateElements() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("must be a set")
}
l := coll.LengthInt()
// Assume that if there are unknowns this could have come from
// a dynamic block, and we can't validate MinItems yet.
if l < blockS.MinItems && coll.IsWhollyKnown() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("insufficient items for attribute %q; must have at least %d", typeName, blockS.MinItems)
}
if l > blockS.MaxItems && blockS.MaxItems > 0 {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("too many items for attribute %q; cannot have more than %d", typeName, blockS.MaxItems)
}
if l == 0 {
attrs[typeName] = cty.SetValEmpty(blockS.ImpliedType())
continue
}
elems := make([]cty.Value, 0, l)
{
path = append(path, cty.GetAttrStep{Name: typeName})
for it := coll.ElementIterator(); it.Next(); {
var err error
idx, val := it.Element()
val, err = blockS.coerceValue(val, append(path, cty.IndexStep{Key: idx}))
if err != nil {
return cty.UnknownVal(b.ImpliedType()), err
}
elems = append(elems, val)
}
}
attrs[typeName] = cty.SetVal(elems)
case blockS.MinItems == 0:
attrs[typeName] = cty.SetValEmpty(blockS.ImpliedType())
default:
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("attribute %q is required", typeName)
}
case NestingMap:
switch {
case ty.HasAttribute(typeName):
coll := in.GetAttr(typeName)
switch {
case coll.IsNull():
attrs[typeName] = cty.NullVal(cty.Map(blockS.ImpliedType()))
continue
case !coll.IsKnown():
attrs[typeName] = cty.UnknownVal(cty.Map(blockS.ImpliedType()))
continue
}
if !coll.CanIterateElements() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("must be a map")
}
l := coll.LengthInt()
if l == 0 {
attrs[typeName] = cty.MapValEmpty(blockS.ImpliedType())
continue
}
elems := make(map[string]cty.Value)
{
path = append(path, cty.GetAttrStep{Name: typeName})
for it := coll.ElementIterator(); it.Next(); {
var err error
key, val := it.Element()
if key.Type() != cty.String || key.IsNull() || !key.IsKnown() {
return cty.UnknownVal(b.ImpliedType()), path.NewErrorf("must be a map")
}
val, err = blockS.coerceValue(val, append(path, cty.IndexStep{Key: key}))
if err != nil {
return cty.UnknownVal(b.ImpliedType()), err
}
elems[key.AsString()] = val
}
}
// If the attribute values here contain any DynamicPseudoTypes,
// the concrete type must be an object.
useObject := false
switch {
case coll.Type().IsObjectType():
useObject = true
default:
// It's possible that we were given a map, and need to coerce it to an object
ety := coll.Type().ElementType()
for _, v := range elems {
if !v.Type().Equals(ety) {
useObject = true
break
}
}
}
if useObject {
attrs[typeName] = cty.ObjectVal(elems)
} else {
attrs[typeName] = cty.MapVal(elems)
}
default:
attrs[typeName] = cty.MapValEmpty(blockS.ImpliedType())
}
default:
// should never happen because above is exhaustive
panic(fmt.Errorf("unsupported nesting mode %#v", blockS.Nesting))
}
}
return cty.ObjectVal(attrs), nil
}
func (a *Attribute) coerceValue(in cty.Value, path cty.Path) (cty.Value, error) {
val, err := convert.Convert(in, a.Type)
if err != nil {
return cty.UnknownVal(a.Type), path.NewError(err)
}
return val, nil
}