Python xlrd: suppress warning messages

Question

I am using xlrd to process Excel files. I am running a script on a folder that contains many files, and I am printing messages related to the files. However, for each file I run, I get the following xlrd-generated error message as well:

WARNING *** OLE2 inconsistency: SSCS size is 0 but SSAT size is non-zero

Is there a way to suppress this error message, so the CLI will only print the message I want it to?

Answer 1

Check out the relevant part of the xlrd docs. The 2nd arg of the open_workbook function is logfile which should be an open file object or act-alike. All it needs to support is a write method. It defaults to sys.stdout.

So, something like this (untested) should do the job:

class MyFilter(object):
    def __init__(self, mylogfile=sys.stdout):
        self.f = mylogfile
    def write(self, data):
        if "WARNING *** OLE2 inconsistency" not in data:
            self.f.write(data)

#start up
log = open("the_log_file.txt", "w")
log_filter = MyFilter(log)
book = xlrd.open_workbook("foo.xls", logfile=log_filter)

# shut down
log.close()
# or use a "with" statement

Update in response to answer by @DaniloBargen:

It's not xlrd that's writing the newline separately, it's the Python print statement/function. This script:

class FakeFile(object):
    def write(self, data):
        print repr(data)

ff = FakeFile()
for x in "foo bar baz".split():
    print >> ff, x

produces this output for all Pythons 2.2 to 2.7 both inclusive:

'foo'
'\n'
'bar'
'\n'
'baz'
'\n'

A suitably modernised script (print as a function instead of a statement) produces identical output for 2.6, 2.7, 3.1, 3.2, and 3.3. You can work around this with a more complicated filter class. The following example additionally allows a sequence of phrases to be checked for:

import sys, glob, xlrd

class MyFilter(object):
    def __init__(self, mylogfile=sys.stdout, skip_list=()):
        self.f = mylogfile
        self.state = 0
        self.skip_list = skip_list
    def write(self, data):
        if self.state == 0:
            found = any(x in data for x in self.skip_list)
            if not found:
                self.f.write(data)
                return
            if data[-1] != '\n':
                self.state = 1
        else:
            if data != '\n':
                self.f.write(data)
            self.state = 0

logf = open("the_log_file.txt", "w")
skip_these = (
    "WARNING *** OLE2 inconsistency",
    )
try:        
    log_filter = MyFilter(logf, skip_these)
    for fname in glob.glob(sys.argv[1]):
        logf.write("=== %s ===\n" % fname)
        book = xlrd.open_workbook(fname, logfile=log_filter)
finally:
    logf.close()