support moved block in migration flow (#138)

CHANGELOG.md

@@ -3,6 +3,7 @@
 FEATURES:
 - Support `-var-file` option to specify the path to the terraform variable file.
 - Support migrating resources from `azurerm` provider to `azapi` provider.
+- When migrating resources from `azurerm` provider to `azapi` provider, it will generate `moved` block to modify the terraform state.
 
 ## v2.0.0-beta
 

cmd/migrate_command.go

@@ -168,9 +168,11 @@ func (c *MigrateCommand) MigrateResources(terraform *tf.Terraform, resources []t
 	for _, r := range resources {
 		if r.IsMigrated() {
 			log.Printf("[INFO] removing %s from config", r.OldAddress(nil))
-			importBlock := r.ImportBlock()
-			removedBlock := r.RemovedBlock()
-			if err := types.ReplaceResourceBlock(workingDirectory, r.OldAddress(nil), []*hclwrite.Block{removedBlock, importBlock, r.MigratedBlock()}); err != nil {
+			stateUpdateBlocks := r.StateUpdateBlocks()
+			newBlocks := make([]*hclwrite.Block, 0)
+			newBlocks = append(newBlocks, stateUpdateBlocks...)
+			newBlocks = append(newBlocks, r.MigratedBlock())
+			if err := types.ReplaceResourceBlock(workingDirectory, r.OldAddress(nil), newBlocks); err != nil {
 				log.Printf("[ERROR] error removing %s from state: %+v", r.OldAddress(nil), err)
 			}
 		}

types/azapi_resource.go

@@ -29,6 +29,13 @@ type AzapiResource struct {
 	Migrated         bool
 }
 
+func (r *AzapiResource) StateUpdateBlocks() []*hclwrite.Block {
+	blocks := make([]*hclwrite.Block, 0)
+	blocks = append(blocks, r.removedBlock())
+	blocks = append(blocks, r.importBlock())
+	return blocks
+}
+
 func (r *AzapiResource) Outputs() []Output {
 	res := make([]Output, 0)
 	for _, instance := range r.Instances {
@@ -49,7 +56,7 @@ func (r *AzapiResource) IsMigrated() bool {
 	return r.Migrated
 }
 
-func (r *AzapiResource) ImportBlock() *hclwrite.Block {
+func (r *AzapiResource) importBlock() *hclwrite.Block {
 	importBlock := hclwrite.NewBlock("import", nil)
 	if r.IsMultipleResources() {
 		forEachMap := make(map[string]cty.Value)
@@ -72,7 +79,7 @@ func (r *AzapiResource) ImportBlock() *hclwrite.Block {
 	return importBlock
 }
 
-func (r *AzapiResource) RemovedBlock() *hclwrite.Block {
+func (r *AzapiResource) removedBlock() *hclwrite.Block {
 	removedBlock := hclwrite.NewBlock("removed", nil)
 	removedBlock.Body().SetAttributeTraversal("from", hcl.Traversal{hcl.TraverseRoot{Name: "azapi_resource"}, hcl.TraverseAttr{Name: r.Label}})
 	removedLifecycleBlock := hclwrite.NewBlock("lifecycle", nil)

types/azapi_update_resource.go

@@ -30,6 +30,12 @@ type AzapiUpdateResource struct {
 	OutputProperties []string
 }
 
+func (r *AzapiUpdateResource) StateUpdateBlocks() []*hclwrite.Block {
+	blocks := make([]*hclwrite.Block, 0)
+	blocks = append(blocks, r.removedBlock())
+	return blocks
+}
+
 func (r *AzapiUpdateResource) Outputs() []Output {
 	res := make([]Output, 0)
 	res = append(res, r.outputs...)
@@ -63,11 +69,7 @@ func (r *AzapiUpdateResource) GenerateNewConfig(terraform *tf.Terraform) error {
 	return nil
 }
 
-func (r *AzapiUpdateResource) ImportBlock() *hclwrite.Block {
-	return nil
-}
-
-func (r *AzapiUpdateResource) RemovedBlock() *hclwrite.Block {
+func (r *AzapiUpdateResource) removedBlock() *hclwrite.Block {
 	removedBlock := hclwrite.NewBlock("removed", nil)
 	removedBlock.Body().SetAttributeTraversal("from", hcl.Traversal{hcl.TraverseRoot{Name: "azapi_update_resource"}, hcl.TraverseAttr{Name: r.OldLabel}})
 	removedLifecycleBlock := hclwrite.NewBlock("lifecycle", nil)

types/azure_resource.go

@@ -16,8 +16,7 @@ type AzureResource interface {
 	GenerateNewConfig(terraform *tf.Terraform) error
 	EmptyImportConfig() string
 
-	ImportBlock() *hclwrite.Block
-	RemovedBlock() *hclwrite.Block
+	StateUpdateBlocks() []*hclwrite.Block
 	MigratedBlock() *hclwrite.Block
 
 	IsMigrated() bool

types/azurerm_resource.go

@@ -4,7 +4,6 @@ import (
 	"fmt"
 	"log"
 	"net/url"
-	"strconv"
 	"strings"
 
 	"github.com/Azure/aztfmigrate/helper"
@@ -14,7 +13,6 @@ import (
 	_ "github.com/gertd/go-pluralize"
 	"github.com/hashicorp/hcl/v2"
 	"github.com/hashicorp/hcl/v2/hclwrite"
-	"github.com/zclconf/go-cty/cty"
 )
 
 var _ AzureResource = &AzurermResource{}
@@ -30,6 +28,15 @@ type AzurermResource struct {
 	Migrated        bool
 }
 
+func (r *AzurermResource) StateUpdateBlocks() []*hclwrite.Block {
+	movedBlock := hclwrite.NewBlock("moved", nil)
+	movedBlock.Body().SetAttributeTraversal("from", hcl.Traversal{hcl.TraverseRoot{Name: r.OldResourceType}, hcl.TraverseAttr{Name: r.OldLabel}})
+	movedBlock.Body().SetAttributeTraversal("to", hcl.Traversal{hcl.TraverseRoot{Name: r.NewResourceType}, hcl.TraverseAttr{Name: r.NewLabel}})
+	blocks := make([]*hclwrite.Block, 0)
+	blocks = append(blocks, movedBlock)
+	return blocks
+}
+
 func (r *AzurermResource) Outputs() []Output {
 	res := make([]Output, 0)
 	for _, instance := range r.Instances {
@@ -109,42 +116,12 @@ func (r *AzurermResource) GenerateNewConfig(terraform *tf.Terraform) error {
 		}
 		r.Block = InjectReference(r.Block, r.References)
 	}
+
+	r.Block = sortAttributes(r.Block)
 	r.Migrated = true
 	return nil
 }
 
-func (r *AzurermResource) ImportBlock() *hclwrite.Block {
-	importBlock := hclwrite.NewBlock("import", nil)
-	if r.IsMultipleResources() {
-		forEachMap := make(map[string]cty.Value)
-		for _, instance := range r.Instances {
-			switch v := instance.Index.(type) {
-			case string:
-				forEachMap[instance.ResourceId] = cty.StringVal(v)
-			default:
-				value, _ := strconv.ParseInt(fmt.Sprintf("%v", v), 10, 64)
-				forEachMap[instance.ResourceId] = cty.NumberIntVal(value)
-			}
-		}
-		importBlock.Body().SetAttributeValue("for_each", cty.MapVal(forEachMap))
-		importBlock.Body().SetAttributeTraversal("id", hcl.Traversal{hcl.TraverseRoot{Name: "each"}, hcl.TraverseAttr{Name: "key"}})
-		importBlock.Body().SetAttributeTraversal("to", hcl.Traversal{hcl.TraverseRoot{Name: r.NewResourceType}, hcl.TraverseAttr{Name: fmt.Sprintf("%s[each.value]", r.NewLabel)}})
-	} else {
-		importBlock.Body().SetAttributeValue("id", cty.StringVal(r.Instances[0].ResourceId))
-		importBlock.Body().SetAttributeTraversal("to", hcl.Traversal{hcl.TraverseRoot{Name: r.NewResourceType}, hcl.TraverseAttr{Name: r.NewLabel}})
-	}
-	return importBlock
-}
-
-func (r *AzurermResource) RemovedBlock() *hclwrite.Block {
-	removedBlock := hclwrite.NewBlock("removed", nil)
-	removedBlock.Body().SetAttributeTraversal("from", hcl.Traversal{hcl.TraverseRoot{Name: r.OldResourceType}, hcl.TraverseAttr{Name: r.OldLabel}})
-	removedLifecycleBlock := hclwrite.NewBlock("lifecycle", nil)
-	removedLifecycleBlock.Body().SetAttributeValue("destroy", cty.BoolVal(false))
-	removedBlock.Body().AppendBlock(removedLifecycleBlock)
-	return removedBlock
-}
-
 func (r *AzurermResource) TargetProvider() string {
 	return "azapi"
 }
@@ -270,3 +247,33 @@ func ResourceTypeOfResourceId(input string) string {
 	}
 	return resourceType
 }
+
+func sortAttributes(input *hclwrite.Block) *hclwrite.Block {
+	output := hclwrite.NewBlock(input.Type(), input.Labels())
+	attrList := []string{"count", "for_each", "type", "parent_id", "name", "location", "identity", "body", "tags"}
+	usedAttr := make(map[string]bool)
+	for _, attr := range attrList {
+		if attribute := input.Body().GetAttribute(attr); attribute != nil {
+			output.Body().SetAttributeRaw(attr, attribute.Expr().BuildTokens(nil))
+			usedAttr[attr] = true
+		} else {
+			for _, block := range input.Body().Blocks() {
+				if block.Type() == attr {
+					output.Body().AppendBlock(block)
+					usedAttr[attr] = true
+				}
+			}
+		}
+	}
+	for attrName, attribute := range input.Body().Attributes() {
+		if _, ok := usedAttr[attrName]; !ok {
+			output.Body().SetAttributeRaw(attrName, attribute.Expr().BuildTokens(nil))
+		}
+	}
+	for _, block := range input.Body().Blocks() {
+		if _, ok := usedAttr[block.Type()]; !ok {
+			output.Body().AppendBlock(block)
+		}
+	}
+	return output
+}

types/hcl.go

@@ -96,7 +96,7 @@ func ReplaceGenericOutputs(workingDirectory string, outputs []Output) error {
 			continue
 		}
 		for _, block := range f.Body().Blocks() {
-			if block.Type() == "removed" || block.Type() == "import" {
+			if block.Type() == "removed" || block.Type() == "import" || block.Type() == "moved" {
 				continue
 			}
 			if block != nil {