feat: Converts data sources (#24)

* datasources

* refactor

* rename resource to block

* set use_replication_spec_per_shard in data sources

* more tests

Author: lantoli

internal/convert/const_names.go

@@ -47,4 +47,5 @@ const (
 	nZoneName                   = "zone_name"
 	nKey                        = "key"
 	nValue                      = "value"
+	nUseRepSpecsPerShard        = "use_replication_spec_per_shard"
 )

internal/convert/convert.go

@@ -14,17 +14,20 @@ import (
 )
 
 const (
-	resourceType   = "resource"
-	cluster        = "mongodbatlas_cluster"
-	advCluster     = "mongodbatlas_advanced_cluster"
-	valClusterType = "REPLICASET"
-	valMaxPriority = 7
-	valMinPriority = 1
-	errFreeCluster = "free cluster (because no " + nRepSpecs + ")"
-	errRepSpecs    = "setting " + nRepSpecs
-	errConfigs     = "setting " + nConfig
-	errPriority    = "setting " + nPriority
-	errNumShards   = "setting " + nNumShards
+	resourceType     = "resource"
+	dataSourceType   = "data"
+	cluster          = "mongodbatlas_cluster"
+	advCluster       = "mongodbatlas_advanced_cluster"
+	clusterPlural    = "mongodbatlas_clusters"
+	advClusterPlural = "mongodbatlas_advanced_clusters"
+	valClusterType   = "REPLICASET"
+	valMaxPriority   = 7
+	valMinPriority   = 1
+	errFreeCluster   = "free cluster (because no " + nRepSpecs + ")"
+	errRepSpecs      = "setting " + nRepSpecs
+	errConfigs       = "setting " + nConfig
+	errPriority      = "setting " + nPriority
+	errNumShards     = "setting " + nNumShards
 )
 
 type attrVals struct {
@@ -42,35 +45,60 @@ func ClusterToAdvancedCluster(config []byte) ([]byte, error) {
 	if err != nil {
 		return nil, err
 	}
-	for _, resource := range parser.Body().Blocks() {
-		labels := resource.Labels()
-		resourceName := labels[0]
-		if resource.Type() != resourceType || resourceName != cluster {
-			continue
-		}
-		resourceb := resource.Body()
-		if errDyn := checkDynamicBlock(resourceb); errDyn != nil {
-			return nil, errDyn
-		}
-		labels[0] = advCluster
-		resource.SetLabels(labels)
-
-		if resourceb.FirstMatchingBlock(nRepSpecs, nil) != nil {
-			err = fillCluster(resourceb)
-		} else {
-			err = fillFreeTierCluster(resourceb)
-		}
+	for _, block := range parser.Body().Blocks() {
+		converted, err := convertResource(block)
 		if err != nil {
 			return nil, err
 		}
-
-		resourceb.AppendNewline()
-		hcl.AppendComment(resourceb, "Generated by atlas-cli-plugin-terraform.")
-		hcl.AppendComment(resourceb, "Please confirm that all references to this resource are updated.")
+		converted = converted || convertDataSource(block)
+		if converted {
+			blockb := block.Body()
+			blockb.AppendNewline()
+			hcl.AppendComment(blockb, "Generated by atlas-cli-plugin-terraform.")
+			hcl.AppendComment(blockb, "Please confirm that all references to this resource are updated.")
+		}
 	}
 	return parser.Bytes(), nil
 }
 
+func convertResource(block *hclwrite.Block) (bool, error) {
+	if block.Type() != resourceType || getResourceName(block) != cluster {
+		return false, nil
+	}
+	setResourceName(block, advCluster)
+	blockb := block.Body()
+	if errDyn := checkDynamicBlock(blockb); errDyn != nil {
+		return false, errDyn
+	}
+
+	var err error
+	if blockb.FirstMatchingBlock(nRepSpecs, nil) != nil {
+		err = fillCluster(blockb)
+	} else {
+		err = fillFreeTierCluster(blockb)
+	}
+	if err != nil {
+		return false, err
+	}
+	return true, nil
+}
+
+func convertDataSource(block *hclwrite.Block) bool {
+	if block.Type() != dataSourceType {
+		return false
+	}
+	convertMap := map[string]string{
+		cluster:       advCluster,
+		clusterPlural: advClusterPlural,
+	}
+	if newName, found := convertMap[getResourceName(block)]; found {
+		setResourceName(block, newName)
+		block.Body().SetAttributeValue(nUseRepSpecsPerShard, cty.True)
+		return true
+	}
+	return false
+}
+
 // fillFreeTierCluster is the entry point to convert clusters in free tier
 func fillFreeTierCluster(resourceb *hclwrite.Body) error {
 	resourceb.SetAttributeValue(nClusterType, cty.StringVal(valClusterType))
@@ -301,6 +329,23 @@ func getAutoScalingOpt(opt map[string]hclwrite.Tokens) hclwrite.Tokens {
 	return hcl.TokensObject(fileb)
 }
 
+func setResourceName(resource *hclwrite.Block, name string) {
+	labels := resource.Labels()
+	if len(labels) == 0 {
+		return
+	}
+	labels[0] = name
+	resource.SetLabels(labels)
+}
+
+func getResourceName(resource *hclwrite.Block) string {
+	labels := resource.Labels()
+	if len(labels) == 0 {
+		return ""
+	}
+	return labels[0]
+}
+
 func checkDynamicBlock(body *hclwrite.Body) error {
 	for _, block := range body.Blocks() {
 		if block.Type() == "dynamic" {

internal/convert/testdata/clu2adv/data_sources.in.tf

@@ -0,0 +1,50 @@
+data "mongodbatlas_cluster" "singular" {
+  # data source content is kept - singular
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+  name       = mongodbatlas_advanced_cluster.example.name
+  depends_on = [mongodbatlas_privatelink_endpoint_service.example_endpoint]
+}
+
+data "mongodbatlas_clusters" "plural" {
+  # data source content is kept - plural
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+}
+
+data "mongodbatlas_advanced_cluster" "adv_singular" {
+  # adv_cluster is not changed - adv_singular
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+  name       = mongodbatlas_advanced_cluster.example.name
+}
+
+data "mongodbatlas_advanced_cluster" "adv_plural" {
+  # adv_cluster is not changed - adv_plural
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+}
+
+resource "random_resource" "random1" {
+  # other resources are left unchanged - random1
+  hi1 = "there1"
+}
+
+data "random_datasource" "random2" {
+  # other resources are left unchanged - random2
+  hi2 = "there2"
+}
+
+# comments out of resources are kept
+
+unknown_block "hello" {
+  # unkown block types are kept
+}
+
+unknown_block {
+  # plugin doesn't panic with unlabeled blocks - unknown_block
+}
+
+resource {
+  # plugin doesn't panic with unlabeled blocks - resource
+}
+
+data {
+  # plugin doesn't panic with unlabeled blocks - data
+}

internal/convert/testdata/clu2adv/data_sources.out.tf

@@ -0,0 +1,58 @@
+data "mongodbatlas_advanced_cluster" "singular" {
+  # data source content is kept - singular
+  project_id                     = mongodbatlas_advanced_cluster.example.project_id
+  name                           = mongodbatlas_advanced_cluster.example.name
+  depends_on                     = [mongodbatlas_privatelink_endpoint_service.example_endpoint]
+  use_replication_spec_per_shard = true
+
+  # Generated by atlas-cli-plugin-terraform.
+  # Please confirm that all references to this resource are updated.
+}
+
+data "mongodbatlas_advanced_clusters" "plural" {
+  # data source content is kept - plural
+  project_id                     = mongodbatlas_advanced_cluster.example.project_id
+  use_replication_spec_per_shard = true
+
+  # Generated by atlas-cli-plugin-terraform.
+  # Please confirm that all references to this resource are updated.
+}
+
+data "mongodbatlas_advanced_cluster" "adv_singular" {
+  # adv_cluster is not changed - adv_singular
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+  name       = mongodbatlas_advanced_cluster.example.name
+}
+
+data "mongodbatlas_advanced_cluster" "adv_plural" {
+  # adv_cluster is not changed - adv_plural
+  project_id = mongodbatlas_advanced_cluster.example.project_id
+}
+
+resource "random_resource" "random1" {
+  # other resources are left unchanged - random1
+  hi1 = "there1"
+}
+
+data "random_datasource" "random2" {
+  # other resources are left unchanged - random2
+  hi2 = "there2"
+}
+
+# comments out of resources are kept
+
+unknown_block "hello" {
+  # unkown block types are kept
+}
+
+unknown_block {
+  # plugin doesn't panic with unlabeled blocks - unknown_block
+}
+
+resource {
+  # plugin doesn't panic with unlabeled blocks - resource
+}
+
+data {
+  # plugin doesn't panic with unlabeled blocks - data
+}

internal/convert/testdata/clu2adv/free_cluster_with_count.in.tf

@@ -4,17 +4,13 @@ resource "resource1" "res1" {
 
 resource "mongodbatlas_cluster" "free_cluster" { # comment in the resource
   # comment in own line in the beginning
-  count                       = local.use_free_cluster ? 1 : 0
-  project_id                  = var.project_id # inline comment kept
-  name                        = var.cluster_name
+  count      = local.use_free_cluster ? 1 : 0
+  project_id = var.project_id # inline comment kept
+  name       = var.cluster_name
   # comment in own line in the middle is deleted
   provider_name               = "TENANT" # inline comment for attribute moved is not kept
   backing_provider_name       = "AWS"
   provider_region_name        = var.region
   provider_instance_size_name = "M0"
   # comment in own line at the end happens before replication_specs
 }
-
-data "mongodbatlas_cluster" "cluster2" {
-  name = "name4"
-}

internal/convert/testdata/clu2adv/free_cluster_with_count.out.tf

@@ -28,7 +28,3 @@ resource "mongodbatlas_advanced_cluster" "free_cluster" { # comment in the resou
   # Generated by atlas-cli-plugin-terraform.
   # Please confirm that all references to this resource are updated.
 }
-
-data "mongodbatlas_cluster" "cluster2" {
-  name = "name4"
-}