package configs
import (
"fmt"
"github.com/hashicorp/terraform/addrs"
"github.com/hashicorp/hcl2/hcl"
"github.com/zclconf/go-cty/cty"
"github.com/zclconf/go-cty/cty/convert"
)
// The methods in this file are used by Module.mergeFile to apply overrides
// to our different configuration elements. These methods all follow the
// pattern of mutating the receiver to incorporate settings from the parameter,
// returning error diagnostics if any aspect of the parameter cannot be merged
// into the receiver for some reason.
//
// User expectation is that anything _explicitly_ set in the given object
// should take precedence over the corresponding settings in the receiver,
// but that anything omitted in the given object should be left unchanged.
// In some cases it may be reasonable to do a "deep merge" of certain nested
// features, if it is possible to unambiguously correlate the nested elements
// and their behaviors are orthogonal to each other.
func (p *Provider) merge(op *Provider) hcl.Diagnostics {
var diags hcl.Diagnostics
if op.Version.Required != nil {
p.Version = op.Version
}
p.Config = MergeBodies(p.Config, op.Config)
return diags
}
func mergeProviderVersionConstraints(recv map[string][]VersionConstraint, ovrd []*ProviderRequirement) {
// Any provider name that's mentioned in the override gets nilled out in
// our map so that we'll rebuild it below. Any provider not mentioned is
// left unchanged.
for _, reqd := range ovrd {
delete(recv, reqd.Name)
}
for _, reqd := range ovrd {
recv[reqd.Name] = append(recv[reqd.Name], reqd.Requirement)
}
}
func (v *Variable) merge(ov *Variable) hcl.Diagnostics {
var diags hcl.Diagnostics
if ov.DescriptionSet {
v.Description = ov.Description
v.DescriptionSet = ov.DescriptionSet
}
if ov.Default != cty.NilVal {
v.Default = ov.Default
}
if ov.Type != cty.NilType {
v.Type = ov.Type
}
if ov.ParsingMode != 0 {
v.ParsingMode = ov.ParsingMode
}
// If the override file overrode type without default or vice-versa then
// it may have created an invalid situation, which we'll catch now by
// attempting to re-convert the value.
//
// Note that here we may be re-converting an already-converted base value
// from the base config. This will be a no-op if the type was not changed,
// but in particular might be user-observable in the edge case where the
// literal value in config could've been converted to the overridden type
// constraint but the converted value cannot. In practice, this situation
// should be rare since most of our conversions are interchangable.
if v.Default != cty.NilVal {
val, err := convert.Convert(v.Default, v.Type)
if err != nil {
// What exactly we'll say in the error message here depends on whether
// it was Default or Type that was overridden here.
switch {
case ov.Type != cty.NilType && ov.Default == cty.NilVal:
// If only the type was overridden
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid default value for variable",
Detail: fmt.Sprintf("Overriding this variable's type constraint has made its default value invalid: %s.", err),
Subject: &ov.DeclRange,
})
case ov.Type == cty.NilType && ov.Default != cty.NilVal:
// Only the default was overridden
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid default value for variable",
Detail: fmt.Sprintf("The overridden default value for this variable is not compatible with the variable's type constraint: %s.", err),
Subject: &ov.DeclRange,
})
default:
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Invalid default value for variable",
Detail: fmt.Sprintf("This variable's default value is not compatible with its type constraint: %s.", err),
Subject: &ov.DeclRange,
})
}
} else {
v.Default = val
}
}
return diags
}
func (l *Local) merge(ol *Local) hcl.Diagnostics {
var diags hcl.Diagnostics
// Since a local is just a single expression in configuration, the
// override definition entirely replaces the base definition, including
// the source range so that we'll send the user to the right place if
// there is an error.
l.Expr = ol.Expr
l.DeclRange = ol.DeclRange
return diags
}
func (o *Output) merge(oo *Output) hcl.Diagnostics {
var diags hcl.Diagnostics
if oo.Description != "" {
o.Description = oo.Description
}
if oo.Expr != nil {
o.Expr = oo.Expr
}
if oo.SensitiveSet {
o.Sensitive = oo.Sensitive
o.SensitiveSet = oo.SensitiveSet
}
// We don't allow depends_on to be overridden because that is likely to
// cause confusing misbehavior.
if len(oo.DependsOn) != 0 {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Unsupported override",
Detail: "The depends_on argument may not be overridden.",
Subject: oo.DependsOn[0].SourceRange().Ptr(), // the first item is the closest range we have
})
}
return diags
}
func (mc *ModuleCall) merge(omc *ModuleCall) hcl.Diagnostics {
var diags hcl.Diagnostics
if omc.SourceSet {
mc.SourceAddr = omc.SourceAddr
mc.SourceAddrRange = omc.SourceAddrRange
mc.SourceSet = omc.SourceSet
}
if omc.Count != nil {
mc.Count = omc.Count
}
if omc.ForEach != nil {
mc.ForEach = omc.ForEach
}
if len(omc.Version.Required) != 0 {
mc.Version = omc.Version
}
mc.Config = MergeBodies(mc.Config, omc.Config)
// We don't allow depends_on to be overridden because that is likely to
// cause confusing misbehavior.
if len(mc.DependsOn) != 0 {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Unsupported override",
Detail: "The depends_on argument may not be overridden.",
Subject: mc.DependsOn[0].SourceRange().Ptr(), // the first item is the closest range we have
})
}
return diags
}
func (r *Resource) merge(or *Resource) hcl.Diagnostics {
var diags hcl.Diagnostics
if r.Mode != or.Mode {
// This is always a programming error, since managed and data resources
// are kept in separate maps in the configuration structures.
panic(fmt.Errorf("can't merge %s into %s", or.Mode, r.Mode))
}
if or.Count != nil {
r.Count = or.Count
}
if or.ForEach != nil {
r.ForEach = or.ForEach
}
if or.ProviderConfigRef != nil {
r.ProviderConfigRef = or.ProviderConfigRef
}
if r.Mode == addrs.ManagedResourceMode {
// or.Managed is always non-nil for managed resource mode
if or.Managed.Connection != nil {
r.Managed.Connection = or.Managed.Connection
}
if or.Managed.CreateBeforeDestroySet {
r.Managed.CreateBeforeDestroy = or.Managed.CreateBeforeDestroy
r.Managed.CreateBeforeDestroySet = or.Managed.CreateBeforeDestroySet
}
if len(or.Managed.IgnoreChanges) != 0 {
r.Managed.IgnoreChanges = or.Managed.IgnoreChanges
}
if or.Managed.PreventDestroySet {
r.Managed.PreventDestroy = or.Managed.PreventDestroy
r.Managed.PreventDestroySet = or.Managed.PreventDestroySet
}
if len(or.Managed.Provisioners) != 0 {
r.Managed.Provisioners = or.Managed.Provisioners
}
}
r.Config = MergeBodies(r.Config, or.Config)
// We don't allow depends_on to be overridden because that is likely to
// cause confusing misbehavior.
if len(or.DependsOn) != 0 {
diags = append(diags, &hcl.Diagnostic{
Severity: hcl.DiagError,
Summary: "Unsupported override",
Detail: "The depends_on argument may not be overridden.",
Subject: or.DependsOn[0].SourceRange().Ptr(), // the first item is the closest range we have
})
}
return diags
}
