opentofu/configs/provider.go
Martin Atkins 8b511524d6
Initial steps towards AbsProviderConfig/LocalProviderConfig separation (#23978)
* Introduce "Local" terminology for non-absolute provider config addresses

In a future change AbsProviderConfig and LocalProviderConfig are going to
become two entirely distinct types, rather than Abs embedding Local as
written here. This naming change is in preparation for that subsequent
work, which will also include introducing a new "ProviderConfig" type
that is an interface that AbsProviderConfig and LocalProviderConfig both
implement.

This is intended to be largely just a naming change to get started, so
we can deal with all of the messy renaming. However, this did also require
a slight change in modeling where the Resource.DefaultProviderConfig
method has become Resource.DefaultProvider returning a Provider address
directly, because this method doesn't have enough information to construct
a true and accurate LocalProviderConfig -- it would need to refer to the
configuration to know what this module is calling the provider it has
selected.

In order to leave a trail to follow for subsequent work, all of the
changes here are intended to ensure that remaining work will become
obvious via compile-time errors when all of the following changes happen:
- The concept of "legacy" provider addresses is removed from the addrs
  package, including removing addrs.NewLegacyProvider and
  addrs.Provider.LegacyString.
- addrs.AbsProviderConfig stops having addrs.LocalProviderConfig embedded
  in it and has an addrs.Provider and a string alias directly instead.
- The provider-schema-handling parts of Terraform core are updated to
  work with addrs.Provider to identify providers, rather than legacy
  strings.

In particular, there are still several codepaths here making legacy
provider address assumptions (in order to limit the scope of this change)
but I've made sure each one is doing something that relies on at least
one of the above changes not having been made yet.

* addrs: ProviderConfig interface

In a (very) few special situations in the main "terraform" package we need
to make runtime decisions about whether a provider config is absolute
or local.

We currently do that by exploiting the fact that AbsProviderConfig has
LocalProviderConfig nested inside of it and so in the local case we can
just ignore the wrapping AbsProviderConfig and use the embedded value.

In a future change we'll be moving away from that embedding and making
these two types distinct in order to represent that mapping between them
requires consulting a lookup table in the configuration, and so here we
introduce a new interface type ProviderConfig that can represent either
AbsProviderConfig or LocalProviderConfig decided dynamically at runtime.

This also includes the Config.ResolveAbsProviderAddr method that will
eventually be responsible for that local-to-absolute translation, so
that callers with access to the configuration can normalize to an
addrs.AbsProviderConfig given a non-nil addrs.ProviderConfig. That's
currently unused because existing callers are still relying on the
simplistic structural transform, but we'll switch them over in a later
commit.

* rename LocalType to LocalName

Co-authored-by: Kristin Laemmert <mildwonkey@users.noreply.github.com>
2020-01-31 08:23:07 -05:00

210 lines
6.3 KiB
Go

package configs
import (
"fmt"
"github.com/hashicorp/hcl/v2"
"github.com/hashicorp/hcl/v2/gohcl"
"github.com/hashicorp/hcl/v2/hclsyntax"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/terraform/tfdiags"
)
// Provider represents a "provider" block in a module or file. A provider
// block is a provider configuration, and there can be zero or more
// configurations for each actual provider.
type Provider struct {
Name string
NameRange hcl.Range
Alias string
AliasRange *hcl.Range // nil if no alias set
Version VersionConstraint
Config hcl.Body
DeclRange hcl.Range
}
func decodeProviderBlock(block *hcl.Block) (*Provider, hcl.Diagnostics) {
var diags hcl.Diagnostics
// Produce deprecation messages for any pre-0.12-style
// single-interpolation-only expressions. We do this up front here because
// then we can also catch instances inside special blocks like "connection",
// before PartialContent extracts them.
moreDiags := warnForDeprecatedInterpolationsInBody(block.Body)
diags = append(diags, moreDiags...)
content, config, moreDiags := block.Body.PartialContent(providerBlockSchema)
diags = append(diags, moreDiags...)
provider := &Provider{
Name: block.Labels[0],
NameRange: block.LabelRanges[0],
Config: config,
DeclRange: block.DefRange,
}
if attr, exists := content.Attributes["alias"]; exists {
valDiags := gohcl.DecodeExpression(attr.Expr, nil, &provider.Alias)
diags = append(diags, valDiags...)
provider.AliasRange = attr.Expr.Range().Ptr()
if !hclsyntax.ValidIdentifier(provider.Alias) {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid provider configuration alias",
Detail: fmt.Sprintf("An alias must be a valid name. %s", badIdentifierDetail),
})
}
}
if attr, exists := content.Attributes["version"]; exists {
var versionDiags hcl.Diagnostics
provider.Version, versionDiags = decodeVersionConstraint(attr)
diags = append(diags, versionDiags...)
}
// Reserved attribute names
for _, name := range []string{"count", "depends_on", "for_each", "source"} {
if attr, exists := content.Attributes[name]; exists {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Reserved argument name in provider block",
Detail: fmt.Sprintf("The provider argument name %q is reserved for use by Terraform in a future version.", name),
Subject: &attr.NameRange,
})
}
}
// Reserved block types (all of them)
for _, block := range content.Blocks {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Reserved block type name in provider block",
Detail: fmt.Sprintf("The block type name %q is reserved for use by Terraform in a future version.", block.Type),
Subject: &block.TypeRange,
})
}
return provider, diags
}
// Addr returns the address of the receiving provider configuration, relative
// to its containing module.
func (p *Provider) Addr() addrs.LocalProviderConfig {
return addrs.LocalProviderConfig{
LocalName: p.Name,
Alias: p.Alias,
}
}
func (p *Provider) moduleUniqueKey() string {
if p.Alias != "" {
return fmt.Sprintf("%s.%s", p.Name, p.Alias)
}
return p.Name
}
// ParseProviderConfigCompact parses the given absolute traversal as a relative
// provider address in compact form. The following are examples of traversals
// that can be successfully parsed as compact relative provider configuration
// addresses:
//
// aws
// aws.foo
//
// This function will panic if given a relative traversal.
//
// If the returned diagnostics contains errors then the result value is invalid
// and must not be used.
func ParseProviderConfigCompact(traversal hcl.Traversal) (addrs.LocalProviderConfig, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
ret := addrs.LocalProviderConfig{
LocalName: traversal.RootName(),
}
if len(traversal) < 2 {
// Just a type name, then.
return ret, diags
}
aliasStep := traversal[1]
switch ts := aliasStep.(type) {
case hcl.TraverseAttr:
ret.Alias = ts.Name
return ret, diags
default:
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid provider configuration address",
Detail: "The provider type name must either stand alone or be followed by an alias name separated with a dot.",
Subject: aliasStep.SourceRange().Ptr(),
})
}
if len(traversal) > 2 {
diags = diags.Append(&hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid provider configuration address",
Detail: "Extraneous extra operators after provider configuration address.",
Subject: traversal[2:].SourceRange().Ptr(),
})
}
return ret, diags
}
// ParseProviderConfigCompactStr is a helper wrapper around ParseProviderConfigCompact
// that takes a string and parses it with the HCL native syntax traversal parser
// before interpreting it.
//
// This should be used only in specialized situations since it will cause the
// created references to not have any meaningful source location information.
// If a reference string is coming from a source that should be identified in
// error messages then the caller should instead parse it directly using a
// suitable function from the HCL API and pass the traversal itself to
// ParseProviderConfigCompact.
//
// Error diagnostics are returned if either the parsing fails or the analysis
// of the traversal fails. There is no way for the caller to distinguish the
// two kinds of diagnostics programmatically. If error diagnostics are returned
// then the returned address is invalid.
func ParseProviderConfigCompactStr(str string) (addrs.LocalProviderConfig, tfdiags.Diagnostics) {
var diags tfdiags.Diagnostics
traversal, parseDiags := hclsyntax.ParseTraversalAbs([]byte(str), "", hcl.Pos{Line: 1, Column: 1})
diags = diags.Append(parseDiags)
if parseDiags.HasErrors() {
return addrs.LocalProviderConfig{}, diags
}
addr, addrDiags := ParseProviderConfigCompact(traversal)
diags = diags.Append(addrDiags)
return addr, diags
}
var providerBlockSchema = &hcl.BodySchema{
Attributes: []hcl.AttributeSchema{
{
Name: "alias",
},
{
Name: "version",
},
// Attribute names reserved for future expansion.
{Name: "count"},
{Name: "depends_on"},
{Name: "for_each"},
{Name: "source"},
},
Blocks: []hcl.BlockHeaderSchema{
// _All_ of these are reserved for future expansion.
{Type: "lifecycle"},
{Type: "locals"},
},
}