Index: qscatv4/trunk/ascat.py
===================================================================
---  (revision )
+++ qscatv4/trunk/ascat.py (revision 479)
@@ -1,0 +1,206 @@
+#!/usr/bin/python
+
+"""
+Fetch and extract Ifremer ASCAT Daily NetCDF files.
+
+Usage:
+    python ascat.py start_year start_month end_year end_month
+
+Where:
+    start_year  is YYYY format,
+    start_month is 1-12 for Jan-Dec,
+    end_year    is YYYY format,              
+    end_month   is 1-12 for Jan-Dec.
+"""
+
+__author__    = 'Chris Calloway'
+__email__     = 'cbc@unc.edu'
+__copyright__ = 'Copyright 2012 UNC-CH Dept. of Marine Sciences'
+__license__   = 'GPL2'
+
+import os
+import sys
+import traceback
+import calendar
+import ftplib
+import bz2
+
+ftp_server = 'ftp.ifremer.fr'
+ftp_user   = 'anonymous'
+ftp_pass   = 'cbc@unc.edu'
+ftp_dir    = 'ifremer/cersat/products/gridded/MWF/L3/ASCAT/Daily/Netcdf/'
+
+work_dir   = os.path.join(os.path.sep,
+                          'afs',
+                          'isis.unc.edu',
+                          'depts',
+                          'marine',
+                          'workspace',
+                          'hseim',
+                          'volumes',
+                          'vol1',
+                          'nc_wind_2011',
+                          'satellite')
+base_subdir = os.path.join('ascat', 'daily')
+year_spec   = '%(year)4u'
+month_spec  = '%(month)02u'
+day_spec    = '%(day)02u'
+
+def _fetch(f):
+    """
+    Fetch a single bzip2 file.
+    """
+
+    try:
+        bz = f.nlst()[0]
+        b = open(bz, 'wb')
+    except KeyboardInterrupt:
+        raise
+    except:
+        traceback.print_exc()
+        return None
+    try:
+        print 'Fetching:   %s.' % bz
+        print f.retrbinary('RETR ' + bz, b.write)
+    except KeyboardInterrupt:
+        raise
+    except:
+        traceback.print_exc()
+        b.close()
+        return None
+    else:
+        b.close()
+    return bz
+
+def _extract(bz):
+    """
+    Extract a single bzip2 file.
+    """
+
+    b = os.path.splitext(bz)[0]
+    print 'Extracting: %s.' % b
+    try:
+        dest = open(b, 'wb')
+    except KeyboardInterrupt:
+        raise
+    except:
+        traceback.print_exc()
+        return False
+    try:
+        src  = bz2.BZ2File(bz)
+    except KeyboardInterrupt:
+        raise
+    except:
+        dest.close()
+        traceback.print_exc()
+        return False
+    try:
+        content = src.read()
+    except KeyboardInterrupt:
+        raise
+    except:
+        dest.close()
+        src.close()
+        traceback.print_exc()
+        return False
+    else:
+        src.close()
+    try:
+        dest.write(content)
+    except KeyboardInterrupt:
+        raise
+    except:
+        dest.close()
+        traceback.print_exc()
+        return False
+    else:
+        dest.close()
+    try:
+        os.remove(bz)
+    except KeyboardInterrupt:
+        raise
+    except:
+        traceback.print_exc()
+        return False
+    return True
+                
+
+def _process(f, year, month):
+    """
+    Fetch and extract all the files for a month.
+    """
+
+    format = {'year': year, 'month': month,}
+    try:
+        os.chdir(work_dir)
+        sub_dir = os.path.join(base_subdir,
+                               year_spec % format,
+                               month_spec % format)
+        os.makedirs(sub_dir)
+        os.chdir(sub_dir)
+    except OSError, e:
+        if not str(e).startswith("[Errno 17] File exists"):
+            traceback.print_exc()
+            return False
+    day_range = range(1, calendar.monthrange(year, month)[1] + 1)
+    for day in day_range:
+        format.update({'day': day,})
+        try:
+            print f.cwd(os.path.join(os.path.sep,
+                                     ftp_dir,
+                                     year_spec % format,
+                                     month_spec % format,
+                                     day_spec % format,
+                                     "").replace(os.path.sep, '/'))
+        except KeyboardInterrupt:
+            raise
+        except ftplib.error_perm, e:
+            traceback.print_exc()
+            continue
+        bz = _fetch(f)
+        if not bz: continue
+        if not _extract(bz): continue
+    return True
+
+def ascat(start_year, start_month, end_year, end_month):
+    """
+    Fetch and extract a range of files.
+
+    ascat(start_year, start_month, end_year, end_month) -> None
+
+    start_year  is inclusive.
+    start_month is 1-12 inclusive.
+    end_year    is exclusive.
+    end_month   is 2-13 exclusive.
+    """
+
+    f = ftplib.FTP(ftp_server)
+    print f.login(ftp_user, ftp_pass)
+    year_range = range(start_year, end_year)
+    for year in year_range:
+        if year == year_range[0]:
+            _start_month = start_month
+        else:
+            _start_month = 1
+        if year == year_range[-1]:
+            _end_month = end_month
+        else:
+            _end_month = 13
+        month_range = range(_start_month, _end_month)
+        for month in month_range:
+            if not _process(f, year, month): continue
+    print f.quit()
+
+if __name__ == '__main__':
+    try:
+        if len(sys.argv) != 5: raise
+        start_year  = int(sys.argv[1])
+        start_month = int(sys.argv[2])
+        end_year    = int(sys.argv[3]) + 1
+        end_month   = int(sys.argv[4]) + 1 
+    except KeyboardInterrupt:
+        raise
+    except:
+        print __doc__
+        sys.exit()
+    ascat(start_year, start_month, end_year, end_month)