[Buildbot] #3648: steps/master.py:... DeprecationWarning: Argument strings and environment keys/values passed to reactor.spawnProcess should be str, not unicode.

[Buildbot trac]

#3648: steps/master.py:... DeprecationWarning: Argument strings and environment
keys/values passed to reactor.spawnProcess should be str, not unicode.
--------------------+-----------------------------------------------
Reporter:  dcoshea  |      Owner:
    Type:  defect   |     Status:  new
Priority:  minor    |  Milestone:  undecided
 Version:  0.8.12   |   Keywords:  unicode eight encoding properties
--------------------+-----------------------------------------------
 When a function is passed for the `extract_fn` parameter to
 `SetPropertyFromCommand`, that function is passed unicode strings, so is
 likely to return unicode strings too, but `MasterShellCommand` triggers a
 warning from twisted when those properties containing unicode strings are
 interpolated into command lines.

 With Buildbot 0.8.12 running under Python 2.6 on CentOS 6, when I include
 these steps in a `BuildFactory`:

 {{{
     def my_extract_fn(exit_status, stdout, stderr):
         return {"my_prop": stdout}

     f.addStep(shell.SetPropertyFromCommand(
         command="echo TEST_VALUE",
         extract_fn=my_extract_fn))

     f.addStep(master.MasterShellCommand(Interpolate("echo
 %(prop:my_prop:~NO_VALUE)s")))
 }}}

 `twistd.log` shows:

 {{{
 2016-11-29 14:39:57+1030 [-]
 releaseLocks(<buildbot.steps.shell.SetPropertyFromCommand object at
 0x7f2334069cd0>): []
 2016-11-29 14:39:57+1030 [-]  step 'setproperty' complete: success
 2016-11-29 14:39:57+1030 [-]
 /drv1/buildbot/buildbot/src/buildbot/master/buildbot/steps/master.py:160:
 exceptions.DeprecationWarning: Argument strings and environment
 keys/values passed to reactor.spawnProcess should be str, not unicode.
 2016-11-29 14:39:58+1030 [-]
 releaseLocks(<buildbot.steps.master.MasterShellCommand object at
 0x7f231c09d190>): []
 }}}

 I can see from adding debugging output that my_extract_fn() is being
 passed unicode strings for `stdout` and `stderr`.

 The above is with Twisted 13.1.0.

 I can't reproduce this problem with 0.9.1 with Python 2.7 and Twisted
 16.6.0, even though the newer version of Twisted has the same checks, so I
 assume this has been addressed somewhere in the nine branch within
 Buildbot.

 This issue can be worked around by converting the strings back from
 unicode, e.g.:

 {{{
         return {"my_prop": str(stdout)}
 }}}

 Presumably it wouldn't be so easy if the string was non-ASCII.

--
Ticket URL: <http://trac.buildbot.net/ticket/3648>
Buildbot <http://buildbot.net/>
Buildbot: build/test automation