return tail of a text log file

[Vin]

Hi all,

I need to stream a text log file via web2py. The file is generated by a python script that runs outside web2py, but is saved to the "uploads" folder.

This is what I have in a controller called 2.py:

def index():
    import os
    path=os.path.join(request.folder,'uploads','log.log')
    return response.stream(open(path,'rb'),chunk_size=4096)

When I navigate to ...app/2 the contents of log.log are displayed on the browser, yes. But my problem is that I only need to see the tail of the file (it can get very large), like you would from the command line.

tail -f log.log

Any ideas?

Thanks!

Vin

[Dave S]

Python's seek() has an option to specify "relative to the end of file" for a file open in read mode.
Old docs: <http://docs.python.org/2.4/lib/bltin-file-objects.html>
Current docs: <http://docs.python.org/2/library/stdtypes.html#file-objects>

There is also os.stat()
<http://docs.python.org/2/library/os.html#files-and-directories>
 
/dps

[Dave S]

See also these posts in other forums:

<http://code.activestate.com/recipes/157035-tail-f-in-python/>
<http://stackoverflow.com/questions/6591931/getting-file-size-in-python>

and a broader answer:
<http://blog.gocept.com/2013/07/15/reliable-file-updates-with-python/>