WCST_Import wcs_extract recipe infinite loop and null error in Rasql servlet

[Bang Pham Huu]

here's some stack trace:
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/wcst_import.py", line 153, in <module>
    main()
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/wcst_import.py", line 136, in main
    reg.run_recipe(session)
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/master/recipe/recipe_registry.py", line 89, in run_recipe
    recipe.describe()
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/recipes/wcs_extract/recipe.py", line 91, in describe
    importer = self._get_importer()
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/recipes/wcs_extract/recipe.py", line 124, in _get_importer
    self.importer = Importer(self.resumer, self._get_coverage(), self.options['wms_import'], self.options['scale_levels'])
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/recipes/wcs_extract/recipe.py", line 117, in _get_coverage
    self.options['partitioning_scheme']).get_coverage()
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/util/coverage_reader.py", line 65, in __init__
    self._read()
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/util/coverage_reader.py", line 428, in _read
    intervals = self._get_intervals(coverage_axes, self.partitioning_scheme)
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/util/coverage_reader.py", line 298, in _get_intervals
    axis_intervals.append(Interval(high, low))
  File "/home/dimitar/rasdaman/community/src-install/share/rasdaman/wcst_import/master/importer/interval.py", line 27, in __init__
    def __init__(self, low, high=None):

It seems it's stuck in an infinite loop:

294                          while (resolution > 0 and high <= stop) or (resolution < 0 and stop <= high):
295                              if low < high:
296                                  axis_intervals.append(Interval(low, high))
297                              else:
298 B->                                axis_intervals.append(Interval(high, low))
299                              # To make sure there is no grid pixel slipping through the cracks due to the decimal computations
300                              # start the next slice with one geo pixel before the last one ended.
301                              # Error correction is disabled by default, the user can enable it
302                              low = high - error_correction
303                              high = low + geo_pixels_per_slice
(Pdb) p resolution
-1.2
(Pdb) p low
-34.54
(Pdb) p high
-34.54
(Pdb) p stop
-39.34
(Pdb) p error_correction
0
(Pdb) p geo_pixels_per_slice
-0.0

because the collection is empty (insert failed before):
  INFO [09:52:09] RasqlController@80: Received request: password=rasadmin&query=select encode(c, "netcdf", "{ \"dimensions\": [\"time\", \"lat\", \"lon\"], \"variables\": { \"time\": { \"type\": \"double\", \"metadata\": { \"standard_name\": \"time\", \"long_name\": \"time\", \"units\": \"days since 2001-1-1\", \"axis\": \"T\", \"calendar\": \"360_day\", \"bounds\": \"time_bnds\", \"original_units\": \"seconds since 2001-1-1\" }, \"data\": [15, 45] }, \"lat\": { \"type\": \"double\", \"metadata\": { \"standard_name\": \"latitude\", \"long_name\": \"latitude\", \"units\": \"degrees_north\", \"axis\": \"Y\", \"bounds\": \"lat_bnds\", \"original_units\": \"degrees_north\" }, \"data\": [-79.5, -78.5, -77.5, -76.5, -75.5, -74.5, -73.5, -72.5, -71.5, -70.5] }, \"lon\": { \"type\": \"double\", \"metadata\": { \"standard_name\": \"longitude\", \"long_name\": \"longitude\", \"units\": \"degrees_east\", \"axis\": \"X\", \"bounds\": \"lon_bnds\", \"original_units\": \"degrees_east\" }, \"data\": [1, 3, 5, 7, 9] }, \"tos\": { \"type\": \"byte\", \"metadata\": { \"standard_name\": \"sea_surface_temperature\", \"long_name\": \"Sea Surface Temperature\", \"units\": \"K\", \"cell_methods\": \"time: mean (interval: 30 minutes)\", \"_FillValue\": 1e20, \"missing_value\": 1e20, \"original_name\": \"sosstsst\", \"original_units\": \"degC\", \"history\": \" At 16:37:23 on 01/11/2005: CMOR altered the data in the following ways: added 2.73150E+02 to yield output units; Cyclical dimension was output starting at a different lon;\" } } }, \"metadata\": { \"title\": \"IPSL model output prepared for IPCC Fourth Assessment SRES A2 experiment\", \"institution\": \"IPSL (Institut Pierre Simon Laplace, Paris, France)\", \"source\": \"IPSL-CM4_v1 (2003) : atmosphere : LMDZ (IPSL-CM4_IPCC, 96x71x19), ocean ORCA2 (ipsl_cm4_v1_8, 2x2L31); sea ice LIM (ipsl_cm4_v\", \"contact\": \"Sebastien Denvil, sebastien.denvil@ipsl.jussieu.fr\", \"project_id\": \"IPCC Fourth Assessment\", \"table_id\": \"Table O1 (13 November 2004)\", \"experiment_id\": \"SRES A2 experiment\", \"realization\": 1, \"cmor_version\": 0.96, \"Conventions\": \"CF-1.0\", \"history\": \"YYYY/MM/JJ: data generated; YYYY/MM/JJ+1 data transformed At 16:37:23 on 01/11/2005, CMOR rewrote data to comply with CF standards and IPCC Fourth Assessment requirements\", \"references\": \"Dufresne et al, Journal of Climate, 2015, vol XX, p 136\", \"comment\": \"Test drive\" } }") from test_float_3d_test1 as c&request=ProcessCoverages&service=WCS&username=rasadmin&version=2.0.1
 ERROR [09:52:09] ExceptionAdvice@57: Catched an exception: 
java.lang.NullPointerException
        at petascope.controller.AbstractController.writeResponseResult(AbstractController.java:406)
        at petascope.controller.RasqlController.requestDispatcher(RasqlController.java:83)
        at petascope.controller.RasqlController.handleGet(RasqlController.java:75)