Specify string format arguments as logging function parameters (logging-not-lazy)

Question

I have read all the other solutions for this error and modified my code accordingly, but the error still persists. What am I doing wrong here?

This is my code:

LOGGER.error(
    'There are no frames to download in the chosen ' +
    'time range: %s to %s. Try a different time range with the ' +
    '--start_date and --end_date options. This error can also arise ' +
    'if the downloaded files have been deleted or modified during' +
    'execution.', str(start_date), str(end_date))

Error message:

.tox/pylint/lib/python3.8/site-packages/polaris/fetch/data_fetch_decoder.py:143:8: W1201: Specify string format arguments as logging function parameters (logging-not-lazy)

------------------------------------------------------------------ Your code has been rated at 9.99/10 (previous run: 9.99/10, +0.00)

ERROR: InvocationError for command /home/jai/polaris/.tox/pylint/bin/pylint tests .tox/pylint/lib/python3.8/site-packages/polaris .tox/pylint/lib/python3.8/site-packages/contrib (exited with code 4)

Update 1: Removing the str() conversion gives me the same output but the error persists. As a comment pointed out, the error is caused by some other issue, but my question is still about why is linter giving me that output.

Update 2: Used implicit string concatenation and now I get the following error

W1202: Use % formatting in logging functions and pass the % parameters as arguments (logging-format-interpolation)

Code for implicit string concatenation using formatting:

LOGGER.error(
            '{0} {1} {2} {3} {4}'.format(
                'There are no frames to download in the chosen time range:',
                '%s to %s. Try a different time range with the',
                '--start_date and --end_date options. This error can',
                'also arise if the downloaded files have been deleted',
                'or modified during execution.'), start_date, end_date)

The "Specify string format arguments as logging function parameters" is just a linter output, it's not an error. And your error is unrelated - it's an error in pylint, not in your code. — bruno desthuilliers, Jan 14 '20 at 12:08
I understand, but still why am I getting that linter output despite using the correct logger syntax? — Jai Kotia, Jan 14 '20 at 12:09
I suspect pylint is getting confused by the string concatenation. — user2357112, Jan 14 '20 at 12:23
@user2357112supportsMonica I suspect the same. Any suggestions for a work around? — Jai Kotia, Jan 14 '20 at 12:24
I hate using it (it's a bad feature that causes far more bugs than it's worth), but if you remove the `+` operators and rely on implicit string literal concatenation, pylint might be happy. (Also you forgot a space at the end of one of your literals.) — user2357112, Jan 14 '20 at 12:26
(The "it" in the previous comment refers to implicit string literal concatenation, not pylint, though I do hate using pylint too.) — user2357112, Jan 14 '20 at 12:27
@user2357112supportsMonica can you check the updates on my post? Also I am fairly certain, overcoming this issue will fix my error. — Jai Kotia, Jan 14 '20 at 12:46

score 1 · Answer 1 · answered Jan 14 '20 at 13:18

This fixed the linter warning and my error:

LOGGER.error(
            ' '.join([
                'There are no frames to download in the chosen time ',
                'range: %s to %s. Try a different time range with ',
                'the --start_date and --end_date options. This error ',
                'can also arise if the downloaded files have been',
                'deleted or modified during execution.'
            ]), start_date, end_date)

As @user2357112supportsMonica pointed out, pylint is getting confused by using + for concatenation, so I used implicit string literal concatenation. Voila, it works now!

I meant like `'a' 'b' 'c'`, not `''.join(['a', 'b', 'c'])`, but if this gets pylint to shut up, I guess that works too. (It inhibits compile-time constant folding and has the opposite of the performance effect the poorly-implemented linter check was intended to promote, though.) — user2357112, Jan 14 '20 at 19:20

score 0 · Answer 2 · edited Jul 03 '20 at 08:48

0

W: 70,12: Specify string format arguments as logging function parameters (logging-not-lazy) LOGGER.info("Information: %s"% result)

--CHANGE TO--

LOGGER.info(" Information: %s", result)

edited Jul 03 '20 at 08:48

jizhihaoSAMA

12,336
9
27
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answered Jul 03 '20 at 08:28

satyanarayana

367
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4

Specify string format arguments as logging function parameters (logging-not-lazy)

2 Answers2