Copy a file from Google Drive to my own server - google-drive-api

If you remember, I'm trying to integrate Google Drive within our website, which is built on Elgg. Elgg already has its native file management system.
What we would like to do is to copy a file from Drive to our server, you know, kind of : Send to My Files. The problem is that I don't see any URL in the file metadata indicating where the file is physically stored.
I can see the copy function in Google Drive SDK but I don't think it allows to copy the file on our own server. Unless I've read it wrong.
Can you help me?
Thanks you.

If you are trying to save a file that has content stored in drive (e.g an image, pdf, etc.), the file's metadata should contain a downloadUrl that can be used to retrieve the file's content through an authorized GET request.
For Google Documents (Google Docs, Google Spreadsheets, etc.), the data is stored in a private format that cannot be understand by third party applications. In this case, your app will have to use one of the exposed exportLinks to export the document into a format understood by your application.

Related

File name conversion for cloud storages?

Lets say I have a web URL to a file on a cloud storage (like Dropbox, Google Drive, etc). How do I convert that to the corresponding file path on my pc? On Android? On iOS?
Assuming of course I have the utilities/apps installed locally.
EDIT: I interested in file name the reverse direction too. (I.e. when I have the local file path, what is the web path?)
EDIT 2: #Greg just made me realize that the problem with file name is much worse on Google Drive than on Dropbox.
And that is very bad. :-(
The reason? Google has good search capabilities on Drive and therefor I and many, many others have put their documents on Drive. However, once I found it I must locate it on my on computer/device. (If I want to edit a pdf for example.)
EDIT 3: #Dan McGrath kindly asked what parts remain unsolved.
Short answer: All. ;-)
Long answer: My actual use case, see below.
My actual use case is a Zotero web app. Zotero is a reference database where you store references to scientific articles, web pages, etc. The items stored in Zotero may include PDF files or - which I prefer - links to PDF files.
I just want to be able to easy access (read) this PDF files from any computer through the web app. And on my own computer I want to be able to edit the files with my local PDF editor. (Be it Android, Windows or whatever.)
By using a cloud storage I do not have to download/upload the files myself. The cloud storage takes care of that part.
For the "reverse" scenario, that is, you have a file and you want the Dropbox shared link, you can use this API endpoint, assuming you're connected to the account via the API:
https://www.dropbox.com/developers/core/docs#shares

When/why can file.downloadUrl be empty for a PDF file selected from Google Drive?

Using js file picker to select PDF files from Google Drive.
I'm encountering an instance when the downloadUrl is undefined.
I don't understand what can cause this.
I know downloadUrl can be empty for native Google formats, but these are PDF files.
I'd like to know what scenarios (except native Google formats) can cause an empty downloadUrl.
Thanks
You should use the Drive API to fetch the picked files' metadata in order to retrieve the downloadUrl. https://developers.google.com/drive/v2/reference/files/get
Native Google formats can be downloaded (converted and downloaded) via their exportLinks: https://developers.google.com/drive/v2/reference/files#exportLinks
The response I was receiving was 403.
And the scenario was user accessing "work" Drive (Google Drive for your domain)
Turns out Google Drive for your domain Administrators can restrict the permission to install third party apps.
https://support.google.com/a/answer/6105699?hl=en
User will still be able to allow access for the app and select files. Its just going to fail every time with a 403. Very confusing UX.

Upload part of the file to Google drive

Is it possible to change a large file using google drive api, by uploading only changed part of the file, instead of entire file? I tried to find information about it in the API docs, but there's only support for continue uploading after connection reset. It seems to be an important feature.
No it's not possible. The Drive SDK treats files as atomic data blobs. It knows nothing about the format of content and hence what constitutes a change.

google drive preview generation while uploading document

Can a google drive application generate a preview for a file (which is not handled by google drive by default) when a file of that type is uploaded by the user, rather than creating it using that application?(Assuming the user has authorized that application)
Unfortunately, no, sorry.
The closest we have is being able to generate a third party thumbnail for a file. Your app can decide how the file will appear in the Google Drive thumbnail view by uploading the necessary image(s).
The video here explains it: http://www.youtube.com/watch?v=jG5-9zlaPL8

Determine if a certain File is process by a project that uses Google Drive API

Good day! I am currently developing a website using Google Drive API. However, I am wondering if is it possible to know if a certain file is created/uploaded/shared by the project using an App Id. I was thinking if it is belong to the attributes of a file. But, when i checked, it seems that, there's no such thing.
What I am trying to do, is to filter the files' shared by the other user to the owner of the account using my web site. Is it possible? Any suggestions on how to do it?
Thank you in advance.
File metadata doesn't contain this information unfortunatelly, therefore you can't know if some file was created by your app or not. But FYI Google store it somewhere, if you will try to upload somefile without providing its content type (* / *) and after that try to open this file through browser you will see the message:
No preview available
This item was created with YourAppName, a Google Drive app.
Download this file or use one of the apps you have installed to open it.