From b149e9429030ac8aa53d939390faccc8272e7d03 Mon Sep 17 00:00:00 2001
From: Phil Kuang <pkuang@factset.com>
Date: Fri, 15 Oct 2021 16:08:06 -0400
Subject: [PATCH] fix(catalog:register): support optional locations

Signed-off-by: Phil Kuang <pkuang@factset.com>
---
 .changeset/fair-jeans-heal.md                 |  5 ++
 .../actions/builtin/catalog/register.test.ts  | 38 ++++++++++++++
 .../actions/builtin/catalog/register.ts       | 52 +++++++++++++------
 3 files changed, 79 insertions(+), 16 deletions(-)
 create mode 100644 .changeset/fair-jeans-heal.md

diff --git a/.changeset/fair-jeans-heal.md b/.changeset/fair-jeans-heal.md
new file mode 100644
index 0000000000..48c0adbfc2
--- /dev/null
+++ b/.changeset/fair-jeans-heal.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+Allow `catalog:register` action to register optional locations
diff --git a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.test.ts b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.test.ts
index eb704c729e..e1f8823487 100644
--- a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.test.ts
+++ b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.test.ts
@@ -174,4 +174,42 @@ describe('catalog:register', () => {
       'http://foo/var',
     );
   });
+
+  it('should ignore failures when dry running the location in the catalog if `optional` is set', async () => {
+    addLocation
+      .mockResolvedValueOnce({
+        entities: [],
+      })
+      .mockRejectedValueOnce(new Error('Not found'));
+    await action.handler({
+      ...mockContext,
+      input: {
+        catalogInfoUrl: 'http://foo/var',
+        optional: true,
+      },
+    });
+
+    expect(addLocation).toHaveBeenNthCalledWith(
+      1,
+      {
+        type: 'url',
+        target: 'http://foo/var',
+      },
+      {},
+    );
+    expect(addLocation).toHaveBeenNthCalledWith(
+      2,
+      {
+        dryRun: true,
+        type: 'url',
+        target: 'http://foo/var',
+      },
+      {},
+    );
+
+    expect(mockContext.output).toBeCalledWith(
+      'catalogInfoUrl',
+      'http://foo/var',
+    );
+  });
 });
diff --git a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.ts b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.ts
index 9d4961bfd9..0c08131925 100644
--- a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.ts
+++ b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/catalog/register.ts
@@ -27,8 +27,8 @@ export function createCatalogRegisterAction(options: {
   const { catalogClient, integrations } = options;
 
   return createTemplateAction<
-    | { catalogInfoUrl: string }
-    | { repoContentsUrl: string; catalogInfoPath?: string }
+    | { catalogInfoUrl: string; optional?: boolean }
+    | { repoContentsUrl: string; catalogInfoPath?: string; optional?: boolean }
   >({
     id: 'catalog:register',
     description:
@@ -46,6 +46,12 @@ export function createCatalogRegisterAction(options: {
                   'An absolute URL pointing to the catalog info file location',
                 type: 'string',
               },
+              optional: {
+                title: 'Optional',
+                description:
+                  'Permit the registered location to optionally exist. Default: false',
+                type: 'boolean',
+              },
             },
           },
           {
@@ -64,6 +70,12 @@ export function createCatalogRegisterAction(options: {
                   'A relative path from the repo root pointing to the catalog info file, defaults to /catalog-info.yaml',
                 type: 'string',
               },
+              optional: {
+                title: 'Optional',
+                description:
+                  'Permit the registered location to optionally exist. Default: false',
+                type: 'boolean',
+              },
             },
           },
         ],
@@ -100,22 +112,30 @@ export function createCatalogRegisterAction(options: {
         },
         ctx.token ? { token: ctx.token } : {},
       );
-      const result = await catalogClient.addLocation(
-        {
-          dryRun: true,
-          type: 'url',
-          target: catalogInfoUrl,
-        },
-        ctx.token ? { token: ctx.token } : {},
-      );
 
-      if (result.entities.length > 0) {
-        const { entities } = result;
-        const entity =
-          entities.find(e => !e.metadata.name.startsWith('generated-')) ??
-          entities[0];
-        ctx.output('entityRef', stringifyEntityRef(entity));
+      try {
+        const result = await catalogClient.addLocation(
+          {
+            dryRun: true,
+            type: 'url',
+            target: catalogInfoUrl,
+          },
+          ctx.token ? { token: ctx.token } : {},
+        );
+
+        if (result.entities.length > 0) {
+          const { entities } = result;
+          const entity =
+            entities.find(e => !e.metadata.name.startsWith('generated-')) ??
+            entities[0];
+          ctx.output('entityRef', stringifyEntityRef(entity));
+        }
+      } catch (e) {
+        if (!input.optional) {
+          throw e;
+        }
       }
+
       ctx.output('catalogInfoUrl', catalogInfoUrl);
     },
   });