AWS Explorer now shows a node indicating when CloudFormation Stacks cannot be found in a region (#815)

Author: awschristou

.changes/next-release/Bug Fix-57668a32-9c81-4fce-9356-42780cc147c7.json

@@ -0,0 +1,4 @@
+{
+    "type": "Bug Fix",
+    "description": "AWS Explorer now shows a node indicating when CloudFormation Stacks cannot be found in a region"
+}

package.nls.json

@@ -50,6 +50,7 @@
     "AWS.explorerNode.addRegion.tooltip": "Click to add a region to view functions...",
     "AWS.explorerNode.lambda.noFunctions": "[No Functions found]",
     "AWS.explorerNode.cloudFormation.noFunctions": "[no functions in this CloudFormation]",
+    "AWS.explorerNode.cloudformation.noStacks": "[No Stacks found]",
     "AWS.explorerNode.cloudFormation.error": "Error loading CloudFormation resources",
     "AWS.explorerNode.container.noItems": "[no items]",
     "AWS.explorerNode.lambda.retry": "Unable to load Lambda Functions, click here to retry",

src/lambda/explorer/cloudFormationNodes.ts

@@ -16,29 +16,39 @@ import { AWSTreeErrorHandlerNode } from '../../shared/treeview/nodes/awsTreeErro
 import { AWSTreeNodeBase } from '../../shared/treeview/nodes/awsTreeNodeBase'
 import { ErrorNode } from '../../shared/treeview/nodes/errorNode'
 import { PlaceholderNode } from '../../shared/treeview/nodes/placeholderNode'
+import { makeChildrenNodes } from '../../shared/treeview/treeNodeUtilities'
 import { intersection, toArrayAsync, toMap, toMapAsync, updateInPlace } from '../../shared/utilities/collectionUtils'
 import { listCloudFormationStacks, listLambdaFunctions } from '../utils'
 import { LambdaFunctionNode } from './lambdaFunctionNode'
 
 export const CONTEXT_VALUE_CLOUDFORMATION_LAMBDA_FUNCTION = 'awsCloudFormationFunctionNode'
 
-export class CloudFormationNode extends AWSTreeErrorHandlerNode {
+export class CloudFormationNode extends AWSTreeNodeBase {
     private readonly stackNodes: Map<string, CloudFormationStackNode>
 
     public constructor(private readonly regionCode: string) {
         super('CloudFormation', vscode.TreeItemCollapsibleState.Collapsed)
         this.stackNodes = new Map<string, CloudFormationStackNode>()
     }
 
-    public async getChildren(): Promise<(CloudFormationStackNode | ErrorNode)[]> {
-        await this.handleErrorProneOperation(
-            async () => this.updateChildren(),
-            localize('AWS.explorerNode.cloudFormation.error', 'Error loading CloudFormation resources')
-        )
-
-        return !!this.errorNode
-            ? [this.errorNode]
-            : [...this.stackNodes.values()].sort((nodeA, nodeB) => nodeA.stackName.localeCompare(nodeB.stackName))
+    public async getChildren(): Promise<AWSTreeNodeBase[]> {
+        return await makeChildrenNodes({
+            getChildNodes: async () => {
+                await this.updateChildren()
+
+                return [...this.stackNodes.values()]
+            },
+            getErrorNode: async (error: Error) =>
+                new ErrorNode(
+                    this,
+                    error,
+                    localize('AWS.explorerNode.cloudFormation.error', 'Error loading CloudFormation resources')
+                ),
+            getNoChildrenPlaceholderNode: async () =>
+                new PlaceholderNode(this, localize('AWS.explorerNode.cloudformation.noStacks', '[No Stacks found]')),
+            sort: (nodeA: CloudFormationStackNode, nodeB: CloudFormationStackNode) =>
+                nodeA.stackName.localeCompare(nodeB.stackName)
+        })
     }
 
     public async updateChildren(): Promise<void> {

src/test/lambda/explorer/cloudFormationNodes.test.ts

@@ -260,7 +260,23 @@ describe('CloudFormationNode', () => {
         assert.deepStrictEqual(actualChildOrder, expectedChildOrder, 'Unexpected child sort order')
     })
 
-    it('handles error', async () => {
+    it('returns placeholder node if no children are present', async () => {
+        const cloudFormationClient = makeCloudFormationClient([])
+
+        const clientBuilder = {
+            createCloudFormationClient: sandbox.stub().returns(cloudFormationClient)
+        }
+
+        ext.toolkitClientBuilder = (clientBuilder as any) as ToolkitClientBuilder
+
+        const cloudFormationNode = new CloudFormationNode(FAKE_REGION_CODE)
+
+        const children = await cloudFormationNode.getChildren()
+
+        assertNodeListOnlyContainsPlaceholderNode(children)
+    })
+
+    it('has an error node for a child if an error happens during loading', async () => {
         const testNode = new CloudFormationNode(FAKE_REGION_CODE)
         sandbox.stub(testNode, 'updateChildren').callsFake(() => {
             throw new Error('Update Children error!')