Allow shell wildcard in template

This is useful because, for the year 2021, the last part of Aviso file
names varies.

Inst_eddies/inst_eddies_Aviso.py

@@ -10,6 +10,7 @@ import sys
 from dateutil import parser
 import netCDF4
 import inst_eddies
+import glob
 
 def filename_generator(first_file, first_date, last_date, template):
     dirname = path.dirname(first_file)
@@ -23,6 +24,18 @@ def filename_generator(first_file, first_date, last_date, template):
         basename = my_date.strftime(template)
         nc_file = path.join(dirname, basename)
 
+        # The template may contain a wild card as long as there is no
+        # more than one file matching it. A missing file is ok and
+        # will be dealt with in inst_eddies.py.
+
+        path_list = glob.glob(nc_file)
+
+        if len(path_list) == 1:
+            nc_file = path_list[0]
+        elif len(path_list) >= 2:
+            sys.exit("inst_eddies_Aviso.py:filename_generator: more than one "
+                     "file matching template")
+
 argparser = argparse.ArgumentParser()
 argparser.add_argument("first_file",
                        help = "NetCDF file containing SSH and velocity at a "
@@ -31,7 +44,8 @@ argparser.add_argument("slice", type = int,
                        help = "slice number to create")
 argparser.add_argument("--template",
                        help = "template of basename with date.strftime format "
-                       "codes, only used for several dates")
+                       "codes (and possible shell wildcards), only used for "
+                       "several dates")
 argparser.add_argument("-l", "--last_date", help = "%%Y-%%m-%%d")
 argparser.add_argument("-b", "--bbox", nargs=4, type = float,
                        metavar = ("xmin", "xmax", "ymin", "ymax"))