I need help with displaying previews of files stored in Google Drive. Right now I’m using the Google Docs viewer but I’m running into some limitations.
The main issue is that the preview only works properly with PDF documents. When I try to preview other file formats like Word docs or spreadsheets, it doesn’t work as expected.
Another important requirement is that I need to keep the files private. I don’t want to make the documents publicly accessible just to generate previews.
Has anyone found a reliable way to create previews for different document types from Google Drive while maintaining file privacy? What are the best approaches or alternatives to the standard Google viewer?
Any suggestions or code examples would be really helpful. Thanks in advance for your help!
I faced a similar issue a while back while developing a document storage solution. The limitations of the Google Docs viewer with non-PDF formats can be quite restrictive, especially when privacy is a concern. I found a more effective approach by utilizing the Google Drive API. I set up a process to convert various document types, such as Word or Excel files, to PDFs on request. Then, I generated previews from these PDFs on my server. To keep the documents private, I created a service account with the necessary OAuth scopes, which allowed me to access the files securely without making them public. While there is some overhead due to the conversion process, implementing caching for frequently accessed documents significantly improved performance while maintaining privacy.
The Google Drive API can generate thumbnails directly using the files.get endpoint with the thumbnailLink field. This works well for Word, Excel, and PowerPoint files without requiring public access. You’ll need to authenticate using OAuth2 credentials to request the thumbnail data, which returns a JPEG preview typically around 220x220 pixels. While the thumbnail quality isn’t ideal for detailed documents, I’ve found that using the Drive API’s export feature to convert documents to HTML first leads to better quality when rendered in an iframe or converted to images server-side. This method maintains privacy as all requests pass through your authenticated app, eliminating the need for public file sharing, and it works particularly well for Google Workspace formats.
There’s another option - combine Google Picker API with Drive API. Users authenticate and browse their own files without making anything public. Picker shows nice previews for most file types (docs, sheets, etc.). I’ve used this before and it works well for keeping files private while getting good previews.