I have a sandboxed application that uses a document format which can contain embedded filenames. E.g. some of these referenced files are for image files which the user selects in order to associate the image file with data stored in the document. Whilst such images will sometimes be located in the users pictures folder, sometimes they are elsewhere. The document format itself cannot be changed for portability reasons (it is shared with an existing Windows version of the app).
In order for the app to be able to access the files whose names are embedded within the document, when the user selects a filename (using nsopenpanel) to be stored in the document like this, the app also creates an app-scoped security scoped bookmark for each such stored filename. It then stores these bookmarks by serialising them to another file. When the app runs again it loads its previously serialised bookmarks and uses them when accessing the 'embedded' filename and that works fine.
But when I copy such a document (and its associated serialised bookmarks file) from one Mac to another, it doesnt work, even though all the files the bookmarks refer to are known to exist on both Macs. What happens is that whilst the app opens the document file ok (after the user selected it with an nsopenpanel), and successfully reads in the serialised bookmarks from its associated serialised bookmarks file (which again the user has selected using nsopenpanel), and even though the exact same filenames that the bookmarks refer to are known to exist on the other Mac (and can be accessed by the user through finder etc), the sandboxed app still cannot access them. Resolving the bookmarks seems to fail.
The question is: are app-scoped bookmarks restricted to only working on the Mac on which they were created? If I cannot move an app-scoped bookmark from one system to another, how else can I achieve the effect I want without forcing the user to have to manually re-select every such 'embedded' filename with an nsopenpanel?
Tried to find the answer to this question in the Apple docs without success.
I take it it goes without saying that security-scoped bookmarks can only be used by the app that creates them.
No, because if this were possible, developers could save security-scoped bookmarks to sensitive files/directories on their own computers and then deploy their apps and have access to those same sensitive files/directories on other peoples' computers.
Related
I have a somewhat unique situation, and while I understand what the problem is, I'm not quite sure what the best workaround may be so I thought I would consult the hive mind. :)
Scenario:
I am working on an application (OS X) that is document based and uses Quicktime. When a new document is created, the user selects a movie to view within the document window. The user can then save this document. When the user later attempts to open the document, nothing happens. It just doesn't open.
What I know so far:
The problem is with the way Sandbox operates, and my limited experience working with it (my first attempt.) I have enabled Sandbox and have the app permissions set to allow any user initiated file operations, and also added permissions for the app to access the Movies folder.
When the user loads a document and the Movie is in the Movies folder, it opens and works correctly. However, if the Movie is anywhere else on the users drive, it does NOT work and performs as described above.
I realized this is because while the user can open the document (user initiated), sandbox is blocking the application when it attempts to then open the linked movie automatically (NOT user initiated) unless the movie is located within the Movies folder.
Since the application is designed to work with large files, it seems like a big limitation to force users to copy the files into their movie folder and leave them there.
(I have not yet tried working with a movie located on an external drive, but suspect that it would work as it's not a system drive.)
Question:
Is there a way to work around this, since the user initiated the task of opening the movie originally?
If not, is there perhaps a way to have the application ask the user to confirm that the movie should be loaded... perhaps like presenting an OPEN dialog box with the movie already selected so they can just click OK? This might be the best solution.
Another option might be to automatically copy the movie into the Movies folder when the user initially selects it, but again it's not really idea for my situation...
Any thoughts would be appreciated!
As you describe it, your App has privileges to access files within its own container and in the Movies folder. To access arbitrary movie files you have to:
Let the user initiate the access to a file, i.e. when a new document is created the user has to use a file chooser to access a movie file. The privileges of your sandbox are then extended to allow access to the selected file.
Those access rights are temporarily. To persist them over App restarts you have to save and restore the access right via security scoped bookmarks.
Refer to Apples documentation on PowerBox and on Security Scoped Bookmarks
Also Session 710 from WWDC 2013 might be helpful.
I am distributing my OS X application on individual USBs and, for this reason, everything must be self contained.
The app itself lets users input information and then saves this information to an existing text file (specifically an ObjectDB database). Herein is my problem.
I'd like to keep this text file inside the app itself (i.e. inside the Content folder) so it's out of the way and can't be deleted by the average user. But once the app is signed, it seems the text file can't be altered with any new information without getting flagged by Gatekeeper. Is this really the case? There's no way to store data files within apps now?
I'd appreciate any suggestions. Thanks.
Yes, you are correct. If you modify the application package, the signed package is no longer valid. That's kind of the purpose of signing a package.
Your options are to store the text file in a temporary folder on the user's computer, or to instruct your users to disable gatekeeper (don't do this).
I have a mac AVRecording app, which records a video and save it to a location selected via NSSavePanel. It was working fine till I sandboxed the app.
For sandboxing I have added the following entitlements
com.apple.security.files.user-selected.read-write
com.apple.security.assets.movies.read-write
com.apple.security.files.downloads.read-write
This enables saving to Downloads and movies folder only.
How is it possible to save my file to any desired location, Desktop, Documents etc ?
It's not clear from your question whether you are referring to saving a particular file (in which case you can use the NSSavePanel and manually copy the file using NSFileManager to write the file into the user-specified new file), or whether you are referring to having the user choose a location for all future downloads.
If you want to prompt the user for a location to use for future downloads, you'll need to use the secure bookmark entitlement and secure bookmarks to retain access to the folder.
There's another stackoverflow answer about sandboxing which covers the process of saving and using the secure bookmark.
I have a Cocoa app "PDFHistory" on Mac OS X that uses the NSDocument architecture to save and load PDF files that are internally formatted specially for my app. I want to make it so whenever I save a file (e.g., "mydoc.pdf") from PDFHistory, then subsequently double-clicking on mydoc.pdf will automatically open it in PDFHistory.app. However, I don't want to make it so all .pdf files are automatically opened in PDFHistory, but rather use the system default (probably Preview.app). The .pdf suffix is a requirement, though, since I need the user to be able to e-mail the files to other users who can view the file in their default PDF viewer.
The problem is that if I set the LSHandlerRank to "Owner", then all .pdf files will be opened with PDFHistory, which is bad (since I only understand the internals of the .pdf file that PDFHistory wrote out). But if I set LSHandlerRank to "Alternate", then all .pdf files will be opened to the system default app (Preview.app), which is confusing for the user who had just created the file using my app.
Once upon a time, "creator codes" could be used to implement this sort of capability, but launch services started ignoring them back in Snow Leopard (see http://tidbits.com/article/10537). UTIs are not a substitute that provide this capability (see http://boredzo.org/blog/archives/2009-09-22/how-not-to-use-utis).
Using Finder to get info on the file allows the user to specify a specific app to use to open the specific file. This supposedly works by setting a "usro" property in a the file's resource. There is some open-source code to mimic this behavior (https://github.com/AlanQuatermain/SetAppAffinity), but is uses deprecated functions, and so would cause Apple to reject the app from the App Store. Similarly, people have posted AppleScript to set this property (https://discussions.apple.com/thread/2597365), but sandboxing would prevent me from invoking it.
Although the .pdf suffix is a requirement in order to be able to send the files to users on other systems/platforms, I considered trying to have the suffix registered with two extensions as ".phistory.pdf", which would allow "file.phistory.pdf" to be opened in PDFHistory, but "file.pdf" would be opened in the default PDF viewer. However, this simply didn't work: it appears that the final suffix is the only one used by launch services, and everything before that is ignored.
So is there any way to have my app be the default app for opening files that it created itself?
I came across this information in the posting of a question I found on here:
"Apple has added an extra rule for apps being submitted to the app store.
We can no longer store arbitrary data files in the Documents folder. Only content generated by the user like a text file they manually typed and saved or a photo they took with the camera can be saved in the Documents folder.
We are now expected to store our app generated files in the Library/Cache folder instead of the Documents folder. In addition, we should mark the files we don't want to be sync to iCloud with the skip backup attribute.
Failure to comply with this will result in an app being rejected by Apple.
Reason: The Documents folder is now used for syncing to iCloud. iCloud does a sync every few minutes and if we were to have megabytes of our app generated files stored in the Documents folder, it would get mixed up with the user's own iCloud synced files."
This makes me wonder if the way I have used NSUserDefaults in my app is "legal" in the eyes of apple.
I'm making a simple app that takes user input in about five different places. I'm saving these simple strings in NSUserDefault variables.
My question to anyone that fully understands the statements made within the quotes above is:
Am I saving data in a way that is no longer allowed by apple?
I'm new to the development game, and the information within quotes doesn't make it clear to me (in the context of my app's situation) whether I'm in the wrong or not.
Thanks for the help!
NSUserDefault is the official, supported way of storing user preferences. If that's what you're storing, then it's the correct way to do it.