From 5185c58bf5461933f4ab1ef628e4637c99f18370 Mon Sep 17 00:00:00 2001
From: blam <ben@blam.sh>
Date: Thu, 7 Jul 2022 19:20:52 +0200
Subject: [PATCH 1/3] chore: copy symlinks as is, rather than copying the
 realpath into the place

Signed-off-by: blam <ben@blam.sh>
---
 .../actions/builtin/fetch/template.test.ts        | 15 +++++++++++++++
 .../scaffolder/actions/builtin/fetch/template.ts  |  5 +++--
 2 files changed, 18 insertions(+), 2 deletions(-)

diff --git a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.test.ts b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.test.ts
index 8f641fe2e2..06def076ea 100644
--- a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.test.ts
+++ b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.test.ts
@@ -186,6 +186,10 @@ describe('fetch:template', () => {
               },
               '.${{ values.name }}': '${{ values.itemList | dump }}',
               'a-binary-file.png': aBinaryFile,
+              symlink: mockFs.symlink({
+                path: 'a-binary-file.png',
+              }),
+
               '{% if values.showDummyFile %}dummy-file.txt{% else %}{% endif %}':
                 'dummy file',
               '${{ "dummy-file2.txt" if values.showDummyFile else "" }}':
@@ -265,6 +269,17 @@ describe('fetch:template', () => {
             .then(fObj => fObj.mode),
         ).resolves.toEqual(parseInt('100755', 8));
       });
+      it('copies file symlinks as-is without processing them', async () => {
+        await expect(
+          fs
+            .lstat(`${workspacePath}/target/symlink`)
+            .then(i => i.isSymbolicLink()),
+        ).resolves.toBe(true);
+
+        await expect(
+          fs.realpath(`${workspacePath}/target/symlink`),
+        ).resolves.toBe(`${workspacePath}/target/a-binary-file.png`);
+      });
     });
 
     describe('copyWithoutRender', () => {
diff --git a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.ts b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.ts
index c6d6b86e7b..a1afabc39e 100644
--- a/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.ts
+++ b/plugins/scaffolder-backend/src/scaffolder/actions/builtin/fetch/template.ts
@@ -229,10 +229,11 @@ export function createFetchTemplateAction(options: {
           await fs.ensureDir(outputPath);
         } else {
           const inputFilePath = resolveSafeChildPath(templateDir, location);
+          const stats = await fs.promises.lstat(inputFilePath);
 
-          if (await isBinaryFile(inputFilePath)) {
+          if (stats.isSymbolicLink() || (await isBinaryFile(inputFilePath))) {
             ctx.logger.info(
-              `Copying binary file ${location} to template output path.`,
+              `Copying file binary or symbolic link at ${location}, to template output path.`,
             );
             await fs.copy(inputFilePath, outputPath);
           } else {

From ea6dcb84a47544d931954158d1ce2cd402cafa05 Mon Sep 17 00:00:00 2001
From: blam <ben@blam.sh>
Date: Thu, 7 Jul 2022 19:24:47 +0200
Subject: [PATCH 2/3] chore: added changeset

Signed-off-by: blam <ben@blam.sh>
---
 .changeset/perfect-donuts-applaud.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/perfect-donuts-applaud.md

diff --git a/.changeset/perfect-donuts-applaud.md b/.changeset/perfect-donuts-applaud.md
new file mode 100644
index 0000000000..3b663fa2c2
--- /dev/null
+++ b/.changeset/perfect-donuts-applaud.md
@@ -0,0 +1,5 @@
+---
+'@backstage/plugin-scaffolder-backend': patch
+---
+
+Don't resolve symlinks, treat them as binary files and copy them as-is

From c9bf1c98b5c5c04a39eaf2b4564a55496320f63b Mon Sep 17 00:00:00 2001
From: blam <ben@blam.sh>
Date: Fri, 8 Jul 2022 11:04:40 +0200
Subject: [PATCH 3/3] chore: added some tests to ensure that we skip symlinked
 folders and files

Signed-off-by: blam <ben@blam.sh>
---
 .../files/serializeDirectoryContents.test.ts  | 46 +++++++++++++++++++
 1 file changed, 46 insertions(+)

diff --git a/plugins/scaffolder-backend/src/lib/files/serializeDirectoryContents.test.ts b/plugins/scaffolder-backend/src/lib/files/serializeDirectoryContents.test.ts
index e1ea676ec5..b24a867504 100644
--- a/plugins/scaffolder-backend/src/lib/files/serializeDirectoryContents.test.ts
+++ b/plugins/scaffolder-backend/src/lib/files/serializeDirectoryContents.test.ts
@@ -97,6 +97,52 @@ describe('serializeDirectoryContents', () => {
     ]);
   });
 
+  it('should ignore symlinked files', async () => {
+    mockFs({
+      root: {
+        'a.txt': 'some text',
+        sym: mockFs.symlink({
+          path: './a.txt',
+        }),
+      },
+    });
+
+    await expect(serializeDirectoryContents('root')).resolves.toEqual([
+      {
+        path: 'a.txt',
+        executable: false,
+        content: Buffer.from('some text', 'utf8'),
+      },
+    ]);
+  });
+
+  it('should ignore symlinked folder files', async () => {
+    mockFs({
+      root: {
+        'a.txt': 'some text',
+        linkme: {
+          'b.txt': 'lols',
+        },
+        sym: mockFs.symlink({
+          path: './linkme',
+        }),
+      },
+    });
+
+    await expect(serializeDirectoryContents('root')).resolves.toEqual([
+      {
+        path: 'a.txt',
+        executable: false,
+        content: Buffer.from('some text', 'utf8'),
+      },
+      {
+        path: 'linkme/b.txt',
+        executable: false,
+        content: Buffer.from('lols', 'utf8'),
+      },
+    ]);
+  });
+
   it('should ignore gitignored files', async () => {
     mockFs({
       root: {