Re: [PATCH v2 6/7] perf script python: add Python3 support to sql scripts

From: Arnaldo Carvalho de Melo
Date: Thu Mar 07 2019 - 13:51:52 EST


Em Wed, Mar 06, 2019 at 08:32:42AM -0800, Tony Jones escreveu:
> On 3/6/19 1:26 AM, Adrian Hunter wrote:
> > On 2/03/19 3:19 AM, Tony Jones wrote:
> >> Support both Python2 and Python3 in the exported-sql-viewer.py,
> >> export-to-postgresql.py and export-to-sqlite.py scripts
> >>
> >> There may be differences in the ordering of output lines due to
> >> differences in dictionary ordering etc. However the format within lines
> >> should be unchanged.
> >>
> >> The use of 'from __future__' implies the minimum supported Python2 version
> >> is now v2.6
> >>
> >> Signed-off-by: Tony Jones <tonyj@xxxxxxx>
> >> Signed-off-by: Seeteena Thoufeek <s1seetee@xxxxxxxxxxxxxxxxxx>
> >> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
> >
> > Apart from one issue (see below), it looks good, thank you!
> >
> >> ---
> >> tools/perf/scripts/python/export-to-postgresql.py | 65 +++++++++++++++--------
> >> tools/perf/scripts/python/export-to-sqlite.py | 23 ++++----
> >> tools/perf/scripts/python/exported-sql-viewer.py | 42 ++++++++++-----
> >> 3 files changed, 84 insertions(+), 46 deletions(-)
> >>
> >> diff --git a/tools/perf/scripts/python/export-to-postgresql.py b/tools/perf/scripts/python/export-to-postgresql.py
> >> index 390a351d15ea..439bbbf1e036 100644
> >> --- a/tools/perf/scripts/python/export-to-postgresql.py
> >> +++ b/tools/perf/scripts/python/export-to-postgresql.py
> >> @@ -10,6 +10,8 @@
> >> # FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
> >> # more details.
> >>
> >> +from __future__ import print_function
> >> +
> >> import os
> >> import sys
> >> import struct
> >> @@ -199,6 +201,16 @@ import datetime
> >>
> >> from PySide.QtSql import *
> >>
> >> +if sys.version_info < (3, 0):
> >> + def tobytes(str):
> >> + return str
> >> +else:
> >> + def tobytes(str):
> >> + # Use latin-1 (ISO-8859-1) so all code-points 0-255 will result
> >> + # in one byte (note utf-8 is 2 bytes for values > 128 and
> >> + # ascii is limited to values <= 128)
> >> + return bytes(str, "ISO-8859-1")
> >
> > Probably this should be the server_encoding, but python2 allowed UTF-8
> > so let's just use UTF-8 for now. That will also mean doing the conversion
> > before getting the len(), otherwise len() can be wrong.
>
> I'm not totally understanding what you're saying here. The rationale for
> using latin-1 and not UTF-8 was clearly expressed in the comment. Else you
> do indeed run into length issues.
>
> Would it be easier, since you have a) more familiarity with the code b) some
> specific issues I'm not fully understanding if you just took this patch and
> made the changes you want yourself. I doubt I'll ever use these scripta, my
> interest is purely in eliminating Python2 as a fixed requirement.

Adrian, can you please reply here? I'm not familiar with this tobytes()
python2/python3 difference, what do you mean about using
'server_encoding'? Where is that defined?

- Arnaldo