From 6bbb1022a95661975eaea6edf68e32d4586a4287 Mon Sep 17 00:00:00 2001
From: CrazyMax <crazy-max@users.noreply.github.com>
Date: Fri, 24 Sep 2021 17:22:41 +0200
Subject: [PATCH] Don't set outputs if empty or nil

Signed-off-by: CrazyMax <crazy-max@users.noreply.github.com>
---
 dist/index.js | 6 +++++-
 src/buildx.ts | 6 +++++-
 2 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/dist/index.js b/dist/index.js
index c7b3239..c949d1e 100644
--- a/dist/index.js
+++ b/dist/index.js
@@ -56,7 +56,11 @@ function getMetadata() {
         if (!fs_1.default.existsSync(metadataFile)) {
             return undefined;
         }
-        return fs_1.default.readFileSync(metadataFile, { encoding: 'utf-8' });
+        const content = fs_1.default.readFileSync(metadataFile, { encoding: 'utf-8' }).trim();
+        if (content === 'null') {
+            return undefined;
+        }
+        return content;
     });
 }
 exports.getMetadata = getMetadata;
diff --git a/src/buildx.ts b/src/buildx.ts
index 5d4eb3b..e2a0e51 100644
--- a/src/buildx.ts
+++ b/src/buildx.ts
@@ -14,7 +14,11 @@ export async function getMetadata(): Promise<string | undefined> {
   if (!fs.existsSync(metadataFile)) {
     return undefined;
   }
-  return fs.readFileSync(metadataFile, {encoding: 'utf-8'});
+  const content = fs.readFileSync(metadataFile, {encoding: 'utf-8'}).trim();
+  if (content === 'null') {
+    return undefined;
+  }
+  return content;
 }
 
 export async function isAvailable(): Promise<Boolean> {