Add better test

Author: hansottowirtz

.dockerignore

@@ -2,3 +2,4 @@
 !package-lock.json
 !package.json
 !webpack.config.js
+!test.js

Dockerfile

@@ -12,7 +12,7 @@ RUN npm --no-optional --no-audit --progress=false install
 
 RUN node ./node_modules/webpack/bin/webpack.js
 
-RUN node -e "console.log(require('sharp'))"
+RUN node ./test.js || (echo 'Test failed'; exit 1)
 
 RUN mkdir /dist && \
   echo "cp /build/dist/sharp-layer.zip /dist/sharp-layer.$(uname -m).zip" > /entrypoint.sh && \

test.js

@@ -0,0 +1,6 @@
+const sharp = require('sharp');
+
+// 1x1 png
+const png = Buffer.from('iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mNkYAAAAAYAAjCB0C8AAAAASUVORK5CYII=', 'base64');
+
+sharp(png).rotate(180).toBuffer()