Commit Graph

6 Commits

Author SHA1 Message Date
Svetoslav Ganov
d26d4898fc Print spooler security and some new print service facing APIs.
1. Updated the security mode of the print spooler. Now the spooler
   is not signed with the system key, it is not a privileged app so if
   it gets compromised (PDF rendering is a potential attack vector)
   it cannot access dangerous permissions. Also only the system
   can bind to the spooler.

2. Added APIs for asking a print service to start and stop tracking
   a given printer. This is need for the case when the user selects
   the printer and the print service should do a best effort to keep
   the system updated for the current state of the printer.

3. Added APIs for putting a print job in a blocked state. A print
   service would report the print job as blocked if for some reason
   the printer cannot proceed, e.g. 99 pages are printed but there
   is no paper for the last one. The user has to add more paper
   and the print service can resume the job.

4. Changed the read/write APIs to use ParcelFileDescriptor instead
   of FileDescriptor since the latter does not have a clean API for
   detaching the wrapped Linux file descriptor when one wants to
   push it to native.

5. Added API for getting the size of the printed document so the
   print service can avoid handling big filed over cellular network
   or ask the user if needed.

6. Now the print services that are preinstalled on the system image
   are automatically enabled.

Change-Id: Ia06c311d3d21cabb9e1368f13928e11cd0030918
2013-08-29 15:39:44 -07:00
Svetoslav Ganov
44720af55a Print UI bug fixing and printer discovery refactoring.
1. Added support for selecting a printer from the all printers activity
   that is not in the initial printer selection drop down. The user
   initially sees a sub set of the printers in the drop down and the
   last option is to see all printers in a separate activity. Some
   of the printers in the all printers activity are not shown in the
   initial drop down.

2. Refactored printer discovery by adding (private for now) printer
   discovery app facing APIs. These APIs are needed to support multiple
   printer selection activities (print dialog and all printers activities)
   and also the settings for showing all printers for a service.

   Now multiple apps can request observing for printers and there is
   a centralized mediator that ensures the same printer discovery
   session is used. The mediator dispatches printer discovery specific
   requests to print services. It also aggregates discovered printers
   and delivers them to the interested apps. The mediator minimizes
   printer discovery session creation and starting and stopping discovery
   by sharing the same discovery session and discovery window with
   multiple apps. Lastly, the mediator takes care of print services
   enabled during discovery by bringing them up to the current
   discovery state (create discovery session and start discovery if
   needed). The mediator also reports disappearing of the printers
   of a service removed during discovery and notifies a newly
   registered observers for the currnet printers if the observers are
   added during an active printer discovery session.

3. Fixed bugs in the print UI and implemented some UX tweaks.

Change-Id: I4d0b0c5a6c6f1809b2ba5dbc8e9d63ab3d48f1ef
2013-08-23 18:36:33 +00:00
Svetoslav Ganov
835835ee6f Polish the print spooler loading of stored print jobs.
1. The singleton print spooler isntance is created when the print spooler
   service gets a connection to the system and is destroyed when this
   connection is removed. Note that if the spooler has work, then the
   connection to the system will not be removed.

   When the spooler is created, it reads the stored state and notifies the
   system which in turn dispatches this to the print services.

   When the system connects to the spooler and passes it a connection, we
   schedule a delayed check whether there is work for the spooler. We do
   not handle this immediately to avoid intermitted spinning on and off
   of the spooler process if a client makes a sequence of queries while
   the spooler has really no work.

2. Fixed a bug in the NotificationManagerService where adding a notification
   and removing it immediately after that does not remove the notification.
   The code that is adding a notification is run on a handler thread while
   the code to remove it on the calling thread. This creates a race and
   erroneous results. Now the removal is also scheduled on the handler.

3. Many small fixes here and there.

Change-Id: I6415c253139fa6616393fbe23c659d031a29e1f6
2013-08-04 20:45:10 -07:00
Svetoslav Ganov
8c43376ea8 First cut of the print notifications.
1. Added notifications for a queued print job, for a started print job,
       for ongoing canceling a print job, and for a failed print job. The
       notifications for queued and started state have a cancel action. The
       notification for failed print job has a cancel and a restart action.

    2. Propagating failure message from the print service to the notifications.

    3. PrintJobConfigActivity was not setting the initial value for the
       print job copies and was not updating the UI immediately after creation.

    4. Refactored PrintJobConfigActivity to avoid using the hack to avoid
       reaction for item selection change in a spinner for an event that
       happened before the callback was registered.

    5. Removed the label attribute from PrinterInfo and now PrinterId is
       composed of the printer name and the service component name. This
       is nice since for restarting print jobs we do not need to store
       information about the printer except the printer id which is
       already part of the PrintJobInfo's data. Also the printer name
       is not expected to change anyway.

    6. Allowing cancellation of a queued print job. Also no print job is
       cancelled without asking the managing print service to do that.
       Before we were immediately canceling print jobs in queued state
       but it was possible for a buggy print service to not set the
       print job state to started before starting to do expensive work
       that will not be canceled.

    7. PrintServiceInfo was throwing an exception the the meta-data
       XML for the print service was not well-formed which would crash
       the system process. Now we just ignore not well-formed meta-data.

    8. Removed unused permissions from the PrintSpooler's manifest.

Change-Id: Iba2dd14b487f56e137b90d1da17c3033422ab5e6
2013-08-02 14:22:22 -07:00
Svetoslav Ganov
a00271533f Refactoring of the print sub-system and API clean up.
1. Now a user state has ins own spooler since the spooler app is
   running per user. The user state registers an observer for the state
   of the spooler to get information needed to orchestrate unbinding
   from print serivces that have no work and eventually unbinding from
   the spooler when all no service has any work.

2. Abstracted a remote print service from the perspective of the system
   in a class that is transparently managing binding and unbinding to
   the remote instance.

3. Abstracted the remote print spooler to transparently manage binding
   and unbinding to the remote instance when there is work and when
   there is no work, respectively.

4. Cleaned up the print document adapter (ex-PrintAdapter) APIs to
   enable implementing the all callbacks on a thread of choice. If
   the document is really small, using the main thread makes sense.

   Now if an app that does not need the UI state to layout the printed
   content, it can schedule all the work for allocating resources, laying
   out, writing, and releasing resources on a dedicated thread.

5. Added info class for the printed document that is now propagated
   the the print services. A print service gets an instance of a
   new document class that encapsulates the document info and a method
   to access the document's data.

6. Added APIs for describing the type of a document to the new document
   info class. This allows a print service to do smarts based on the
   doc type. For now we have only photo and document types.

7. Renamed the systemReady method for system services that implement
   it with different semantics to systemRunning. Such methods assume
   the the service can run third-party code which is not the same as
   systemReady.

8. Cleaned up the print job configuration activity.

9. Sigh... code clean up here and there. Factoring out classes to
   improve readability.

Change-Id: I637ba28412793166cbf519273fdf022241159a92
2013-07-16 12:59:59 -07:00
Svetoslav Ganov
4b9a4d1687 Print - platform APIs
Related changes:
    Skia (inlcude PDF APIs): https://googleplex-android-review.googlesource.com/#/c/305814/
    Canvas to PDF: https://googleplex-android-review.googlesource.com/#/c/319367/
    Settings (initial version): https://googleplex-android-review.googlesource.com/#/c/306077/
    Build: https://googleplex-android-review.googlesource.com/#/c/292437/
    Sample print services: https://googleplex-android-review.googlesource.com/#/c/281785/

Change-Id: I104d12efd12577f05c7b9b2a5e5e49125c0f09da
2013-06-21 18:43:17 -07:00