whatnick

#!python
"""
This script is designed to fetch the last few available
radar loop information from the BOM radar
"""

# Let's create a function that downloads a file, and saves it locally.
# This function accepts a file name, a read/write mode(binary or text),
# and the base url.

def downloadData(file_name,file_mode,base_url):
    from urllib2 import Request, urlopen, URLError, HTTPError

    #create the url and the request
    url = base_url + file_name
    req = Request(url)
    req.add_header("User-Agent",
    "Mozilla/5.0 (X11; U; Linux i686) \
    Gecko/20071127 Firefox/2.0.0.11")

    # Open the url
    try:
        f = urlopen(req)
        print "downloading " + url

        # Open our local file for writing
        local_file = open(file_name, "w" + file_mode)
        #Write to our local file
        local_file.write(f.read())
        local_file.close()

    #handle errors
    except HTTPError, e:
        print "HTTP Error:",e.code , url
    except URLError, e:
        print "URL Error:",e.reason , url

# Set the range of images to 1-50.It says 51 because the
# range function never gets to the endpoint.
image_range = range(0,4)

def construct_filename(index):
    """
    Create time date based filename
    """
    from datetime import date,timedelta,datetime
    back_delta = timedelta(minutes=index*10)
    back_time = long((datetime.utcnow()-back_delta).strftime("%Y%m%d%H%M"))
    pad_time = back_time - back_time%10
    file_name = str(pad_time)  + ".png"
    return file_name


# Iterate over image range
for index in image_range:

    base_url = 'http://www.bom.gov.au/radar/IDR643.T.'#.201008251130.png'
    #create file name based on known pattern
    file_name = construct_filename(index)
    # Now download the image. If these were text files,
    # or other ascii types, just pass an empty string
    # for the second param ala downloadData(file_name,'',base_url)
    downloadData(file_name,"b",base_url)