predictors: db tool workaround to solve sqlite3 compatibility problem.

predictors: db tool workaround to solve sqlite3 compatibility problem.

Current version of python sqilte3 library hasn't support of views. But new
sqlite3 binary used in chrome implicitly creates MmapStatus view everytime that
causes incompatibility problem. This workaround creates a temporary copy of
given database and deletes the view through sqlite3 command line tool that has
support of views.

BUG=631966
Review-Url: https://codereview.chromium.org/2620053002
Cr-Commit-Position: refs/heads/master@{#442945}
Committed: https://chromium.googlesource.com/chromium/src/+/37127ecd00687cd497d8ef19067eede1c70dfd76

[alexilin, 2017-01-10 18:22:49]

alexilin@chromium.org changed reviewers:
+ lizeb@chromium.org

[Benoit L, 2017-01-11 09:36:45]

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
File tools/resource_prefetch_predictor/prefetch_predictor_tool.py (right):

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:81: # The current
version of python sqilte3 library doesn't support views but
Not sure about the "current" version, at least the version we happen to have in
Ubuntu 14.04 LTS.

Also, sqlite3 not sqilte3 :-)

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:88:
os.system('sqlite3 %s "DROP VIEW MmapStatus"' % (tmpfile,))
nit: why not subprocess.call(['sqlite3', tmpfile, 'DROP VIEW MmapStatus'])

?

No shell is best shell.

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:107: database_copy
= CreateCompatibleDatabaseCopy(args.database_filename)
nit:

try:
  bla bla
finally:
  os.remove(database_copy)

To not leave files around.

[alexilin, 2017-01-11 12:39:07]

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
File tools/resource_prefetch_predictor/prefetch_predictor_tool.py (right):

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:81: # The current
version of python sqilte3 library doesn't support views but
On 2017/01/11 09:36:45, Benoit L wrote:
> Not sure about the "current" version, at least the version we happen to have
in
> Ubuntu 14.04 LTS.
> 
> Also, sqlite3 not sqilte3 :-)

Done.

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:88:
os.system('sqlite3 %s "DROP VIEW MmapStatus"' % (tmpfile,))
On 2017/01/11 09:36:45, Benoit L wrote:
> nit: why not subprocess.call(['sqlite3', tmpfile, 'DROP VIEW MmapStatus'])
> 
> ?
> 
> No shell is best shell.

Done.

https://codereview.chromium.org/2620053002/diff/1/tools/resource_prefetch_pre...
tools/resource_prefetch_predictor/prefetch_predictor_tool.py:107: database_copy
= CreateCompatibleDatabaseCopy(args.database_filename)
On 2017/01/11 09:36:45, Benoit L wrote:
> nit:
> 
> try:
>   bla bla
> finally:
>   os.remove(database_copy)
> 
> To not leave files around.

Done.

[alexilin, 2017-01-11 12:48:05]

It seems like I didn't sleep well last night :(

[Benoit L, 2017-01-11 16:23:59]

On 2017/01/11 12:48:05, alexilin wrote:
> It seems like I didn't sleep well last night :(

lgtm, thanks.

[alexilin, 2017-01-11 17:22:19]

The CQ bit was checked by alexilin@chromium.org

[commit-bot: I haz the power, 2017-01-11 17:22:36]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2017-01-11 17:36:43]

CQ is committing da patch.

Bot data: {"patchset_id": 60001, "attempt_start_ts": 1484155339099720,
"parent_rev": "3bbebdae9535ea4a21d85e5571a02c6a6fd36383", "commit_rev":
"37127ecd00687cd497d8ef19067eede1c70dfd76"}

[commit-bot: I haz the power, 2017-01-11 17:37:37]

Description was changed from

==========
predictors: db tool workaround to solve sqlite3 compatibility problem.

Current version of python sqilte3 library hasn't support of views. But new
sqlite3 binary used in chrome implicitly creates MmapStatus view everytime that
causes incompatibility problem. This workaround creates a temporary copy of
given database and deletes the view through sqlite3 command line tool that has
support of views.

BUG=631966
==========

to

==========
predictors: db tool workaround to solve sqlite3 compatibility problem.

Current version of python sqilte3 library hasn't support of views. But new
sqlite3 binary used in chrome implicitly creates MmapStatus view everytime that
causes incompatibility problem. This workaround creates a temporary copy of
given database and deletes the view through sqlite3 command line tool that has
support of views.

BUG=631966

Review-Url: https://codereview.chromium.org/2620053002
Cr-Commit-Position: refs/heads/master@{#442945}
Committed:
https://chromium.googlesource.com/chromium/src/+/37127ecd00687cd497d8ef19067e...
==========

[commit-bot: I haz the power, 2017-01-11 17:37:38]

Committed patchset #4 (id:60001) as
https://chromium.googlesource.com/chromium/src/+/37127ecd00687cd497d8ef19067e...