Opened 10 years ago

Closed 10 years ago

Last modified 9 years ago

#305 closed defect (invalid)

sql code was not white space safe?

Reported by: scanner@… Owned by: adrian
Component: Database layer (models, ORM) Version: 1.0
Severity: normal Keywords: quoting strings for 'get_object(<field>__exact = ...)'
Cc: Triage Stage: Unreviewed
Has patch: no Needs documentation: no
Needs tests: no Patch needs improvement: no
Easy pickings: UI/UX:

Description (last modified by adrian)

Using the postgresql backend I have a model which has "albums" which only has two fields. The important field is:

meta.CharField('name', maxlength = 512)

so I create the model fun. Now in python code I do the following:

album = albums.get_object(name__exact = album_name)

Where album was the string "Dungeon Keeper 2"

This died with the error:

  File "/usr/local/lib/python2.4/site-packages/django/utils/functional.py", line 3, in _curried
    return args[0](*(args[1:]+moreargs), **dict(kwargs.items() + morekwargs.items()))
  File "/usr/local/lib/python2.4/site-packages/django/core/meta/__init__.py", line 1013, in function_get_object
    obj_list = function_get_list(opts, klass, **kwargs)
  File "/usr/local/lib/python2.4/site-packages/django/core/meta/__init__.py", line 1053, in function_get_list
    return list(function_get_iterator(opts, klass, **kwargs))
  File "/usr/local/lib/python2.4/site-packages/django/core/meta/__init__.py", line 1036, in function_get_iterator
    cursor.execute("SELECT " + (kwargs.get('distinct') and "DISTINCT " or "") + ",".join(select) + sql, params)
  File "/usr/local/lib/python2.4/site-packages/django/core/db/base.py", line 10, in execute
    result = self.cursor.execute(sql, params)
psycopg.ProgrammingError: ERROR:  syntax error at or near "Keeper" at character 123

SELECT music_albums.id,music_albums.name,music_albums.simplified_name FROM music_albums WHERE music_albums.name = Dungeon Keeper 2

Now if I modified my call to be:

album = albums.get_object(name__exact = "'%s'" % album_name)

it works. (Note the " ' %s ' ") thus quoting the string. I would have thought it would do sql safe quoting of my strings for me?

Attachments (3)

music.py (9.8 KB) - added by scanner@… 10 years ago.
"music" app models/music.py file
scanfiles.py (11.8 KB) - added by scanner@… 10 years ago.
program that scans a 'music root' for files, extracts id3 tags, and fills in the db from that
scanfiles.2.py (12.3 KB) - added by scanner@… 10 years ago.
Okay, new version of scanfiles.py with a small sql safe quoting function..

Download all attachments as: .zip

Change History (11)

comment:1 Changed 10 years ago by jacob

There's got to be something else going on here -- spaces in strings don't cause any problems (see http://www.djangoproject.com/documentation/models/lookup/#sample-usage which is one of our tests). Can you attach your entire model to this ticket so we can take a look?

comment:2 Changed 10 years ago by adrian

  • Description modified (diff)

(Changed formatting in description)

comment:3 Changed 10 years ago by adrian

In this code:

album = albums.get_object(name__exact = album_name)

...is album_name a normal string, a Unicode object, or what?

Changed 10 years ago by scanner@…

"music" app models/music.py file

Changed 10 years ago by scanner@…

program that scans a 'music root' for files, extracts id3 tags, and fills in the db from that

comment:4 Changed 10 years ago by scanner@…

I added two attachments. One is the model the other is the program that I am testing with
to fill in the db - which is where the error actually happens.

The reason I suspected white-space safety was that the track name given in the example
did not work (as the error indicated) but when I replaced the statement that creates
the track with:

track = tracks.Track(title = "'%s'" % title, filename = filename,

last_scanned = datetime.datetime.now(),
play_time = playtime, bit_rate = bitrate, vbr = vbr,
musicroot_id = music_root.id)

it did work. The only difference being the { "'%s'" % title } bit. Now I have another track
that dies that has a single quote (" ' ") in its title. I was going to write a generic
quoting function to pass all these strings through to see if that made it happier.

Hope I am not wasting your time with this and thanks again.

comment:5 Changed 10 years ago by anonymous

Another problem that is I think related is shown by the track title: "Don't Fade Away"

This is the same exact code that I attached to this ticket earlier. I notice also that the file
name looks curious in the failed insert statement:

'/locker/music/goth/Dead_Can_Dance_-_Toward_The_Within/15_Dont_Fade_Away.mp3'

This one I find curious because I do not do my hack of: { "'%s'" % filename } here.

The line in question is:

track = tracks.Track(title = "'%s'" % title, filename = filename,

last_scanned = datetime.datetime.now(),
play_time = playtime, bit_rate = bitrate, vbr = vbr,
musicroot_id = music_root.id)

Here is how it dies:

Traceback (most recent call last):

File "./scanfiles.py", line 339, in ?

main()

File "./scanfiles.py", line 331, in main

run(opts.verbosity)

File "./scanfiles.py", line 270, in run

scan_file(check_file, music_root, verbosity = verbosity)

File "./scanfiles.py", line 220, in scan_file

add_file(filename, af, music_root, verbosity)

File "./scanfiles.py", line 165, in add_file

track.save()

File "/usr/local/lib/python2.4/site-packages/django/utils/functional.py", line 3, in _curried

return args[0](*(args[1:]+moreargs), dict(kwargs.items() + morekwargs.items()))

File "/usr/local/lib/python2.4/site-packages/django/core/meta/init.py", line 747, in method_save

','.join(field_names), ','.join(placeholders)), db_values)

File "/usr/local/lib/python2.4/site-packages/django/core/db/base.py", line 10, in execute

result = self.cursor.execute(sql, params)

psycopg.ProgrammingError: ERROR: syntax error at or near "t" at character 224

INSERT INTO music_tracks (title,filename,simplified_name,year,play_time,bit_rate,vbr,track_number,disc_number,play_count,last_scanned,last_played,bpm,grouping,comments,artist_id,album_id,genre_id,musicroot_id) VALUES ('Don't Fade Away','/locker/music/goth/Dead_Can_Dance_-_Toward_The_Within/15_Dont_Fade_Away.mp3',NULL,NULL,372,128,False,0,0,0,'2005-08-11 21:17:32.314466',NULL,NULL,NULL,NULL,4,5,NULL,2)

(obviously my hack is wrong because I do nothing about checking the quote-safety inside the
string I stuck insdie single quotes.)

Changed 10 years ago by scanner@…

Okay, new version of scanfiles.py with a small sql safe quoting function..

comment:6 Changed 10 years ago by scanner@…

Okay, added a small function to quote out all quotes in a string (and surround the string in
single quotes) and gets a lot further now (before causing python to core dump.. )

Figured I would put this up here because it does get further.

comment:7 Changed 10 years ago by scanner@…

Okay, finally had time to get back to this one specifically.

Yes, the string was a unicode object. In the case where it caused python to core dump (inside psycopg) the issue was that it could
not deal with the unicode object. I am doing a:

if isinstance(foo, unicode):

foo = foo.encode("utf-8")

I am sure the basic problem stems from that as you mentioned it above.

comment:8 Changed 10 years ago by adrian

  • Resolution set to invalid
  • Status changed from new to closed
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