fix: remove public access from do space and generate signed url wherever PDF files are accessed

apps/OpenSignServer/cloud/parsefunction/getSignedUrl.js

@@ -0,0 +1,26 @@
+import AWS from 'aws-sdk';
+const credentials = {
+  accessKeyId: process.env.DO_ACCESS_KEY_ID,
+  secretAccessKey: process.env.DO_SECRET_ACCESS_KEY,
+};
+AWS.config.update({ credentials: credentials, region: process.env.DO_REGION });
+const spacesEndpoint = new AWS.Endpoint(process.env.DO_ENDPOINT);
+
+const s3 = new AWS.S3({ endpoint: spacesEndpoint });
+
+export default function getPresignedUrl(url) {
+  // Create a new URL object
+  const parsedUrl = new URL(url);
+  // Get the pathname of the URL
+  const pathname = parsedUrl.pathname;
+  // Extract the filename from the pathname
+  const filename = pathname.substring(pathname.lastIndexOf('/') + 1);
+
+  // presignedGETURL return presignedUrl with expires time
+  const presignedGETURL = s3.getSignedUrl('getObject', {
+    Bucket: process.env.DO_SPACE,
+    Key: filename, //filename
+    Expires: 160, //time to expire in seconds
+  });
+  return presignedGETURL;
+}