Issue8 sardata

sardata/sardataNBS.py

@@ -0,0 +1,159 @@
+#!/usr/bin/env python3
+# -*- coding: utf-8 -*-
+"""
+Created on Thu Feb  9 09:32:05 2023
+
+@author: froded
+"""
+
+from owslib import fes
+from owslib.fes import SortBy, SortProperty
+from owslib.csw import CatalogueServiceWeb
+
+
+class SARData():
+    """
+    A class for getting Sentinel-1 netCDF data from the Norwegian Ground Segment (NBS)
+
+    Parameters
+    -----------
+    endpoint : str
+               URL to NBS. Default: https://nbs.csw.met.no/csw
+
+    bbox     : int list
+               A boudary box for search area speified in latitude and longitude 
+               bbox = [lon_min, lat_min, lon_max, lat_max]
+
+               Example:
+               >>> bbox = [-10, 75, 40, 85]
+
+    start    : datetime object
+               Specify the start time of the range to serchthe 
+
+    stop     :  datetime object
+               Specify the stop time of the range to serchthe  
+
+               Example:
+               >>> from datetime import datetime, timedelta
+               >>> stop = datetime(2010, 1, 1, 12, 30, 59).replace(tzinfo=pytz.utc)
+               >>> start = stop - timedelta(days=7)
+
+    kw_names : str
+               A search string filter to limit the result of a search. 
+               Example:
+               >>> kw_name='S1A*'    
+
+    """
+
+    def __init__(self, endpoint='https://nbs.csw.met.no/csw', bbox=None, start=None, stop=None, kw_names=None, crs="urn:ogc:def:crs:OGC:1.3:CRS84", *args, **kwargs):
+
+        constraints = []
+        csw = None
+        while csw is None:
+            try:
+                # connect
+                csw = CatalogueServiceWeb(endpoint, timeout=60)
+            except:
+                pass
+
+        if kw_names:
+            kw = dict(wildCard="*", escapeChar="\\", singleChar="?", propertyname="apiso:AnyText")
+            or_filt = fes.Or([fes.PropertyIsLike(literal=("*%s*" % val), **kw) for val in kw_names])
+            constraints.append(or_filt)
+
+
+
+        if all(v is not None for v in [start, stop]): 
+            begin, end = self._fes_date_filter(start, stop)
+            constraints.append(begin)
+            constraints.append(end)
+
+        if bbox:
+            bbox_crs = fes.BBox(bbox, crs=crs)
+            constraints.append(bbox_crs)
+        if len(constraints) >= 2:
+            filter_list = [
+                fes.And(
+                    constraints
+                    )
+            ]
+        else:
+            filter_list = constraints
+
+        self._get_csw_records(csw, filter_list, pagesize=2, maxrecords=10)
+        self.csw = csw
+        url_opendap = []
+
+        for key, value in list(csw.records.items()):
+            for ref in value.references:
+                if ref['scheme'] == 'OPENDAP:OPENDAP':
+                    url_opendap.append(ref['url'])
+        self.url_opendap = url_opendap
+
+
+
+
+    def _get_csw_records(self, csw, filter_list, pagesize=2, maxrecords=10):
+        """Iterate `maxrecords`/`pagesize` times until the requested value in
+        `maxrecords` is reached.
+        """
+        # Iterate over sorted results.
+        sortby = SortBy([SortProperty("dc:title", "ASC")])
+        csw_records = {}
+        startposition = 0
+        nextrecord = getattr(csw, "results", 1)
+        while nextrecord != 0:
+            csw.getrecords2(
+                constraints=filter_list,
+                startposition=startposition,
+                maxrecords=pagesize,
+                sortby=sortby,
+            )
+            csw_records.update(csw.records)
+            if csw.results["nextrecord"] == 0:
+                break
+            startposition += pagesize + 1  # Last one is included.
+            if startposition >= maxrecords:
+                break
+        csw.records.update(csw_records)
+
+
+
+
+    def _fes_date_filter(self, start, stop, constraint="within"):
+        """
+        Take datetime-like objects and returns a fes filter for date range
+        (begin and end inclusive).
+        NOTE: Truncates the minutes!!!
+        """
+
+        start = start.strftime("%Y-%m-%d %H:00")
+        stop = stop.strftime("%Y-%m-%d %H:00")
+        if constraint == "overlaps":
+            propertyname = "apiso:TempExtent_begin"
+            begin = fes.PropertyIsLessThanOrEqualTo(propertyname=propertyname, literal=stop)
+            propertyname = "apiso:TempExtent_end"
+            end = fes.PropertyIsGreaterThanOrEqualTo(
+                propertyname=propertyname, literal=start
+            )
+        elif constraint == "within":
+            propertyname = "apiso:TempExtent_begin"
+            begin = fes.PropertyIsGreaterThanOrEqualTo(
+                propertyname=propertyname, literal=start
+            )
+            propertyname = "apiso:TempExtent_end"
+            end = fes.PropertyIsLessThanOrEqualTo(propertyname=propertyname, literal=stop)
+        else:
+            raise NameError("Unrecognized constraint {}".format(constraint))
+        return begin, end
+
+
+
+
+
+
+
+
+
+
+

tests/test_sarwind.py

@@ -5,6 +5,9 @@
 
 from sarwind.sarwind import SARWind
 
+from sardata.sardataNBS import SARData
+from datetime import datetime, timedelta
+import pytz
 
 @pytest.mark.unittests
 @pytest.mark.sarwind
@@ -79,3 +82,15 @@ def testSARWind_using_s1IWDVsafe_meps_filenames(sarIW_SAFE, meps):
     """
     w = SARWind(sarIW_SAFE, meps)
     assert type(w) == SARWind
+
+@pytest.mark.sardata
+def testSARData_from_NBS():
+    """ Test using CSW for reading Sentinel-1 data.
+        This test requres access to https://nbs.csw.met.no/csw
+    """
+    bbox = [-10, 75, 40, 85]
+    stop = datetime(2022, 1, 8, 5, 30, 59).replace(tzinfo=pytz.utc)
+    start = stop - timedelta(days=1)
+
+    sw = SARData(bbox=bbox, start=start, stop=stop, kw_name='S1A*')
+    assert type(sw) == SARData