~bzr-pqm/bzr/bzr.dev

4584.3.5 by Martin Pool
Developer docs on using apport
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Bazaar Apport Integration
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Bazaar can use Apport <http://launchpad.net/apport/> to capture data about
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unexpected errors (probably, bugs in Bazaar) and report them to the
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developers.
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This is only active for errors that are believed to be internal errors (ie
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bugs) not user or environmental errors.  (See the Developer Guide.)
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Consequences for users
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----------------------
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* They shouldn't normally need to see or copy&paste a traceback.
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* They will be able to inspect the files before sending them to be sure
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  there's no sensitive data included.
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* As at present, they'll need a Launchpad account to report bugs in the
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  normal way.
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Implementation notes
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--------------------
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The use of apport by Bazaar is independent of the configuration in the OS.
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For example in Ubuntu, apport is normally inactive in release builds, and
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normally excludes software not installed from a package.  We'll bypass
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both of them.
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4584.3.9 by Martin Pool
More apport notes
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Putting in this handler may mean that an OS-wide exception handler never
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sees the error, but that was true with our existing exception-printer.
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4584.3.5 by Martin Pool
Developer docs on using apport
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The user should have the option to: forget about the crash (and ignore the
4584.3.15 by Martin Pool
More developer docs about apport
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bug report), see the contents of the report, file a bug, or save the
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report to file later.  At the moment we just show them the filename and
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let them take it from there.
4584.3.5 by Martin Pool
Developer docs on using apport
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The process is 
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#. An exception reaches the top-level handler.
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#. We log it in apport-format to a file in ~/.bazaar/crash.
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4584.3.7 by Martin Pool
Updated documentation about apport
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#. We tell the user where that file is, and invite them to file a bug
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   report.
4584.3.5 by Martin Pool
Developer docs on using apport
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This won't be active for bugs that cause the whole Python interpreter to
4584.3.12 by Martin Pool
Note on interaction of our handler with system-wide apport
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crash.  This can be handled at the OS level.  The nice thing is that if
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apport is active system-wide, it will catch either exceptions in our
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in-process apport handler, or errors that crash the intrepreter.
4584.3.5 by Martin Pool
Developer docs on using apport
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Future ideas
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------------
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* Capture apport data even for things not believed to be internal errors,
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  because sometimes they are in fact bugs.  Then the user can attach the
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  apport report later if they decide to file a bug.  There may be quite a
4584.3.7 by Martin Pool
Updated documentation about apport
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  lot of them so we might need to limit the number that are stored, or do
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  this when a debug flag is set.  At the moment they go into .bzr.log and
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  that's probably ok to start with.
4584.3.5 by Martin Pool
Developer docs on using apport
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* Raising an error from the breakin debugger should cause this to fire.
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* Developers looking at a crash on their own machine will probably in the
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  first instance just want to see the traceback. Apport files may be more
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  longwinded than our current output and might make the traceback scroll
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  off the screen.
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More developer docs about apport
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* Automatically trace messages (ie from .bzr.log) in the report.  We could
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  just include the whole file, but it may be long, and including the whole
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  thing has a greater risk of including sensitive data.
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Updated documentation about apport
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* Ask the user what they want to do with the report: automatically file
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  it, look at it, see just the traceback, just be told where it is.  This
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  could be done through the UIFactory so that it can be done through a
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  graphical dialog.
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  However, if we've already had an unhandled error in this process there
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  may be problems in Bazaar that prevent us presenting a clean message...
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  Possibly these bugs are better reported in the next time bzr runs.
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Developer docs on using apport
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.. 
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    vim: ft=rst