CcdbApi: Fixed logReading in vectoredLoadFileTomemory

[TrifleMichael]

In order do properly print data received from headers in logReading, the line calling logReading has been moved after the execution of downloader loop.

Additionally the warning of "No content received" has been demoted to info, as it is expected in various use cases. For example in case of checking whether data has been modified and receiving 304.

[shahor02]

@TrifleMichael will it show the actual object fetched (with timestamps and etag) like it was before vectorization?

[TrifleMichael]

Yes, it will show the full path including the timestamp and etag like it did before. The problem was calling logReading before the headers arrived, which resulted in requestContext.headers being empty and not containing that information.

[shahor02]

Cannot we suppress the message completely when the content is not supposed to be shipped?

[TrifleMichael]

We can definitely do that in case of receiving http 304. I don't know if there are any other similar cases, but most likely that could be done.

[shahor02]

Only 304 is a legitimate case of not shipping an object, and we don't need to log this case. All other cases I know should produce a LOG(error).

[TrifleMichael]

Then I'll modify the code so it log's an error in case of non-304 response and no object received.

[costing]

In principle only http codes >= 400 should be considered errors and returned. Or libcurl IO errors, if the call could not be performed at all.

[shahor02]

@costing, don't all cases other than 304 already produce an error message:

AliceO2/CCDB/src/CcdbApi.cxx

Lines 970 to 976 in 6ba1cfa

	} else if (response_code == 404) {
	LOG(error) << "Requested resource does not exist: " << url;
	errorflag = true;
	} else {
	LOG(error) << "Error in fetching object " << url << ", curl response code:" << response_code;
	errorflag = true;
	}

?

[costing]

@shahor02 the above if clauses on various ranges of response codes should indeed filter those out ([200, 300) = ok, [300, 400) = redirects, 404 = not found) leaving essentially only other 40x/50x codes to log as an error on the last else clause. And we should be verbose about those as they should not be encountered and we need as much information as possible to understand the context when they might occur.

[shahor02]

@costing So, then it should be ok to log an error in the https://github.com/AliceO2Group/AliceO2/pull/12276/files/6ba1cfa64111499e28a87f1b34eff43647708eaa#diff-2355211fcd8f9232fbeddc19348089f206c655459237baffc0252dbd544dd025R1691 only if a curl code assuming a shipped object was received but the object was not there, right? Effectively response in [200 : 300[ with no payload, since all other cases are already covered by the navigateURLsAndRetrieveContent logs).

[alibuild]

Error while checking build/O2/fullCI for 6ba1cfa at 2023-11-21 22:05:

## sw/BUILD/O2-latest/log
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'


## sw/BUILD/O2Physics-latest/log
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'
c++: error: unrecognized command-line option '--rtlib=compiler-rt'


## sw/BUILD/o2checkcode-latest/log
--
========== List of errors found ==========
++ GRERR=0
++ grep -v clang-diagnostic-error error-log.txt
++ grep ' error:'
/sw/SOURCES/O2/12276-slc8_x86-64/0/Generators/src/GeneratorPythia8.cxx:459:32: error: statement should be inside braces [readability-braces-around-statements]
/sw/SOURCES/O2/12276-slc8_x86-64/0/Generators/src/GeneratorPythia8.cxx:461:32: error: statement should be inside braces [readability-braces-around-statements]
++ [[ 0 == 0 ]]
++ exit 1
--

Full log here.

[TrifleMichael]

@shahor02 I'll update this PR so that errors are logged only if 400+ was received and no content arrived.

[shahor02]

Thanks!