Manage File permissions using REST API

Question

Is there a way to manage File permissions (roles) using the REST API?
http://msdn.microsoft.com/en-us/library/office/jj860569(v=office.15).aspx

I'm developing an app asking for permission on the fly:
http://msdn.microsoft.com/en-us/library/office/jj687470(v=office.15).aspx

I don't care about the way to do it... just want to upload a file to the SharePoint (already implemented that) - and then just make sure other users can't access it (before I delete it).

So any of these solutions will be just fine:

• set permissions on the file itself
• copy it to a folder and set permissions for that folder
• create a 'document library' and set permissions for it (this seems to be doable when you have FullAccess rights - which is not possible to get using the REST API)

Answer 1

In order to manage unique permissions for a Securable Object like List or File (via associated List Item) or Folder (via associated List Item) there is a common approach that you could consider:

• Break role inheritance for a securable object
• Add/remove the role assignment on the securable object [optional]

How to: set unique permissions for a File via REST

Step 1 Break role inheritance for a List Item associated with File

Example:

url: /_api/web/GetFileByServerRelativeUrl('<file relative url>')/ListItemAllFields/breakroleinheritance(true)
method: POST      
Headers: 
   Authorization: "Bearer " + accessToken
   X-RequestDigest: form digest value
   accept: "application/json;odata=verbose"
   content-type: "application/json;odata=verbose"

JavaScript example:

function breakRoleInheritanceOfFile(webUrl,fileUrl,success,failure) { 
     $.ajax({
            url: webUrl + String.format("/_api/web/GetFileByServerRelativeUrl('{0}')/ListItemAllFields/breakroleinheritance(true)",fileUrl),
            type: "POST",
            contentType: "application/json;odata=verbose",
            headers: {
                "Accept": "application/json;odata=verbose",
                "X-RequestDigest": $("#__REQUESTDIGEST").val()
            },
            success: function (data) {
                success(data);
            },
            error: function (data) {
                failure(data);
            }
     });   
}

Note: Specify copyRoleAssignments=false in breakroleinheritance method to prevent copying the role assignments from the parent securable object. In that case the collection of role assignments must contain only 1 role assignment containing the current user after the operation

Step 2 (optional) Add/remove the role assignment on the List Item

Remove the current role assignment for the group on the File:

url: /_api/web/GetFileByServerRelativeUrl('<file relative url>')/ListItemAllFields/roleassignments/getbyprincipalid(<groupId>)
method: POST      
Headers: 
   Authorization: "Bearer " + accessToken
   X-RequestDigest: form digest value
   accept: "application/json;odata=verbose"
   content-type: "application/json;odata=verbose"
   'X-HTTP-Method':'DELETE'

Add the new role assignment for the group on the File:

url: /_api/web/GetFileByServerRelativeUrl('<file relative url>')/ListItemAllFields/roleassignments/addroleassignment(principalid=<groupId>,roledefid=<targetRoleDefinitionId>)
method: POST      
Headers: 
   Authorization: "Bearer " + accessToken
   X-RequestDigest: form digest value
   accept: "application/json;odata=verbose"
   content-type: "application/json;odata=verbose"

References

How to: Set custom permissions on a list by using the REST interface