coder · mtojek · Jul 6, 2023 · Jul 5, 2023 · Jul 5, 2023 · Jul 5, 2023
diff --git a/provisioner/terraform/resources.go b/provisioner/terraform/resources.go
@@ -385,6 +385,7 @@ func ConvertState(modules []*tfjson.StateModule, rawGraph string) (*State, error
 	resourceIcon := map[string]string{}
 	resourceCost := map[string]int32{}
 
+	metadataTargetLabels := map[string]bool{}
 	for _, resources := range tfResourcesByLabel {
 		for _, resource := range resources {
 			if resource.Type != "coder_metadata" {
@@ -396,7 +397,6 @@ func ConvertState(modules []*tfjson.StateModule, rawGraph string) (*State, error
 			if err != nil {
 				return nil, xerrors.Errorf("decode metadata attributes: %w", err)
 			}
-
 			resourceLabel := convertAddressToLabel(resource.Address)
 
 			var attachedNode *gographviz.Node
@@ -433,6 +433,11 @@ func ConvertState(modules []*tfjson.StateModule, rawGraph string) (*State, error
 			}
 			targetLabel := attachedResource.Label
 
+			if metadataTargetLabels[targetLabel] {
+				return nil, xerrors.Errorf("duplicate metadata resource: %s", targetLabel)
+			}
+			metadataTargetLabels[targetLabel] = true
+
 			resourceHidden[targetLabel] = attrs.Hide
 			resourceIcon[targetLabel] = attrs.Icon
 			resourceCost[targetLabel] = attrs.DailyCost

diff --git a/provisioner/terraform/resources_test.go b/provisioner/terraform/resources_test.go
@@ -636,6 +636,25 @@ func TestAppSlugValidation(t *testing.T) {
 	require.ErrorContains(t, err, "duplicate app slug")
 }
 
+func TestMetadataResourceDuplicate(t *testing.T) {
+	t.Parallel()
+
+	// Load the multiple-apps state file and edit it.
+	dir := filepath.Join("testdata", "resource-metadata-duplicate")
+	tfPlanRaw, err := os.ReadFile(filepath.Join(dir, "resource-metadata-duplicate.tfplan.json"))
+	require.NoError(t, err)
+	var tfPlan tfjson.Plan
+	err = json.Unmarshal(tfPlanRaw, &tfPlan)
+	require.NoError(t, err)
+	tfPlanGraph, err := os.ReadFile(filepath.Join(dir, "resource-metadata-duplicate.tfplan.dot"))
+	require.NoError(t, err)
+
+	state, err := terraform.ConvertState([]*tfjson.StateModule{tfPlan.PlannedValues.RootModule}, string(tfPlanGraph))
+	require.Nil(t, state)
+	require.Error(t, err)
+	require.ErrorContains(t, err, "duplicate metadata resource: null_resource.about")
+}
+
 func TestParameterValidation(t *testing.T) {
 	t.Parallel()
 

diff --git a/provisioner/terraform/testdata/resource-metadata-duplicate/resource-metadata-duplicate.tf b/provisioner/terraform/testdata/resource-metadata-duplicate/resource-metadata-duplicate.tf
@@ -0,0 +1,51 @@
+terraform {
+  required_providers {
+    coder = {
+      source  = "coder/coder"
+      version = "0.9.0"
+    }
+  }
+}
+
+resource "coder_agent" "main" {
+  os   = "linux"
+  arch = "amd64"
+  metadata {
+    key          = "process_count"
+    display_name = "Process Count"
+    script       = "ps -ef | wc -l"
+    interval     = 5
+    timeout      = 1
+  }
+}
+
+resource "null_resource" "about" {
+  depends_on = [
+    coder_agent.main,
+  ]
+}
+
+resource "coder_metadata" "about_info" {
+  resource_id = null_resource.about.id
+  hide        = true
+  icon        = "/icon/server.svg"
+  daily_cost  = 29
+  item {
+    key   = "hello"
+    value = "world"
+  }
+  item {
+    key = "null"
+  }
+}
+
+resource "coder_metadata" "other_info" {
+  resource_id = null_resource.about.id
+  hide        = true
+  icon        = "/icon/server.svg"
+  daily_cost  = 20
+  item {
+    key   = "hello"
+    value = "world"
+  }
+}
diff --git a/...ner/terraform/testdata/resource-metadata-duplicate/resource-metadata-duplicate.tfplan.dot b/...ner/terraform/testdata/resource-metadata-duplicate/resource-metadata-duplicate.tfplan.dot