terraform/internal/configs/removed.go

// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: BUSL-1.1

package configs

import (
	"github.com/hashicorp/terraform/internal/addrs"

	"github.com/hashicorp/hcl/v2"
	"github.com/hashicorp/hcl/v2/gohcl"
)

// Removed describes the contents of a "removed" block in configuration.
type Removed struct {
	// From is the address of the configuration object being removed.
	From *addrs.RemoveTarget

	// Destroy indicates that the resource should be destroyed, not just removed
	// from state. Defaults to true.
	Destroy bool

	DeclRange hcl.Range
}

func decodeRemovedBlock(block *hcl.Block) (*Removed, hcl.Diagnostics) {
	var diags hcl.Diagnostics
	removed := &Removed{
		DeclRange: block.DefRange,
	}

	content, moreDiags := block.Body.Content(removedBlockSchema)
	diags = append(diags, moreDiags...)

	if attr, exists := content.Attributes["from"]; exists {
		from, traversalDiags := hcl.AbsTraversalForExpr(attr.Expr)
		diags = append(diags, traversalDiags...)
		if !traversalDiags.HasErrors() {
			from, fromDiags := addrs.ParseRemoveTarget(from)
			diags = append(diags, fromDiags.ToHCL()...)
			removed.From = from
		}
	}

	removed.Destroy = true

	for _, block := range content.Blocks {
		switch block.Type {
		case "lifecycle":
			lcContent, lcDiags := block.Body.Content(removedLifecycleBlockSchema)
			diags = append(diags, lcDiags...)

			if attr, exists := lcContent.Attributes["destroy"]; exists {
				valDiags := gohcl.DecodeExpression(attr.Expr, nil, &removed.Destroy)
				diags = append(diags, valDiags...)
			}
		}
	}

	return removed, diags
}

var removedBlockSchema = &hcl.BodySchema{
	Attributes: []hcl.AttributeSchema{
		{
			Name:     "from",
			Required: true,
		},
	},
	Blocks: []hcl.BlockHeaderSchema{
		{
			Type: "lifecycle",
		},
	},
}

var removedLifecycleBlockSchema = &hcl.BodySchema{
	Attributes: []hcl.AttributeSchema{
		{
			Name: "destroy",
		},
	},
}