chore: streaming secret to file

[ci skip]

Author: aryanjassal

src/secrets/CommandEdit.ts

@@ -74,10 +74,21 @@ class CommandEdit extends CommandPolykey {
               metadata: auth,
             });
             await writer.close();
-            let rawSecretContent: string = '';
+            let fileWriter: fs.WriteStream | undefined = undefined;
             for await (const chunk of response.readable) {
               if (chunk.type === 'SuccessMessage') {
-                rawSecretContent += chunk.secretContent;
+                // Only create the file if we are getting data
+                if (fileWriter == null) {
+                  fileWriter = fs.createWriteStream(tmpFile, { flags: 'a' });
+                }
+                // Wait for the internal buffer to drain if it is full
+                if (
+                  !fileWriter.write(Buffer.from(chunk.secretContent, 'binary'))
+                ) {
+                  await new Promise((resolve) =>
+                    fileWriter!.once('drain', resolve),
+                  );
+                }
               } else {
                 if (chunk.code === 'ENOENT') {
                   exists = false;
@@ -101,12 +112,8 @@ class CommandEdit extends CommandPolykey {
                 }
               }
             }
-            // Only make the temp file is the secret actually exists
-            if (exists) {
-              const secretContent = Buffer.from(rawSecretContent, 'binary');
-              await this.fs.promises.writeFile(tmpFile, secretContent);
-              return exists;
-            }
+            if (fileWriter != null) fileWriter.end();
+            return exists;
           },
           meta,
         );