pyproj.crs updates/fixes (is_proj/to_proj4/to_dict/from_string) (#359)

- added 'is_proj';
fixed case in 'to_dict' with 'to_proj4' returning None
keep no_defs as it does not hurt anything in current code and it preserves backwards compatibility with older versions
made public properties on C classes readonly

docs/api/crs.rst

@@ -16,6 +16,12 @@ pyproj.crs.is_wkt
 .. autofunction:: pyproj.crs.is_wkt
 
 
+pyproj.crs.is_proj
+------------------
+
+.. autofunction:: pyproj.crs.is_proj
+
+
 Area Of Use
 -----------
 

docs/history.rst

@@ -1,14 +1,18 @@
 Change Log
 ==========
 
-2.2.1
+2.2.2
 ~~~~~
 * Added custom warnings for pyproj (pull #358)
 * Add deprecation warning when using +init= syntax (pull #358)
+* Added :meth:`~pyproj.crs.is_proj` (pull #359)
+* Fixed case in :meth:`~pyproj.crs.CRS.to_dict` with :meth:`~pyproj.crs.CRS.to_proj4` returning None (pull #359)
+* Keep `no_defs` in input PROJ string as it does not hurt/help anything in current code (pull #359)
+* Made public properties on C classes readonly (pull #359)
 
 2.2.1
 ~~~~~
-* Added :meth:`~pyproj.show_versions()` (issue #334)
+* Added :meth:`~pyproj.show_versions` (issue #334)
 * Added fix for whitepace around '=' in PROJ strings (issue #345)
 * Update version check in `setup.py` (issue #323)
 * Add "stable" doc site pointing to latest release (issue #347, pull #348)

pyproj/_crs.pxd

@@ -1,23 +1,23 @@
 include "proj.pxi"
 
 cdef class Axis:
-    cdef public object name
-    cdef public object abbrev
-    cdef public object direction
-    cdef public double unit_conversion_factor
-    cdef public object unit_name
-    cdef public object unit_auth_code
-    cdef public object unit_code
+    cdef readonly object name
+    cdef readonly object abbrev
+    cdef readonly object direction
+    cdef readonly double unit_conversion_factor
+    cdef readonly object unit_name
+    cdef readonly object unit_auth_code
+    cdef readonly object unit_code
 
     @staticmethod
     cdef create(PJ_CONTEXT* projcontext, PJ* projobj, int index)
 
 cdef class AreaOfUse:
-    cdef public double west
-    cdef public double south
-    cdef public double east
-    cdef public double north
-    cdef public object name
+    cdef readonly double west
+    cdef readonly double south
+    cdef readonly double east
+    cdef readonly double north
+    cdef readonly object name
 
     @staticmethod
     cdef create(PJ_CONTEXT* projcontext, PJ* projobj)
@@ -26,81 +26,81 @@ cdef class AreaOfUse:
 cdef class Base:
     cdef PJ *projobj
     cdef PJ_CONTEXT *projctx
-    cdef public object name
+    cdef readonly object name
 
 
 cdef class Ellipsoid(Base):
     cdef double _semi_major_metre
     cdef double _semi_minor_metre
-    cdef public object is_semi_minor_computed
+    cdef readonly object is_semi_minor_computed
     cdef double _inv_flattening
-    cdef public object ellipsoid_loaded
+    cdef readonly object ellipsoid_loaded
 
     @staticmethod
     cdef create(PJ* ellipsoid_pj)
 
 cdef class PrimeMeridian(Base):
-    cdef public double longitude
-    cdef public double unit_conversion_factor
-    cdef public object unit_name
+    cdef readonly double longitude
+    cdef readonly double unit_conversion_factor
+    cdef readonly object unit_name
 
     @staticmethod
     cdef create(PJ* prime_meridian_pj)
 
 
 cdef class Datum(Base):
-    cdef public object _ellipsoid
-    cdef public object _prime_meridian
+    cdef readonly object _ellipsoid
+    cdef readonly object _prime_meridian
 
     @staticmethod
     cdef create(PJ* datum_pj)
 
 
 cdef class CoordinateSystem(Base):
-    cdef public object _axis_list
+    cdef readonly object _axis_list
 
     @staticmethod
     cdef create(PJ* coordinate_system_pj)
 
 
 cdef class Param:
-    cdef public object name
-    cdef public object auth_name
-    cdef public object code
-    cdef public object value
-    cdef public double unit_conversion_factor
-    cdef public object unit_name
-    cdef public object unit_auth_name
-    cdef public object unit_code
-    cdef public object unit_category
+    cdef readonly object name
+    cdef readonly object auth_name
+    cdef readonly object code
+    cdef readonly object value
+    cdef readonly double unit_conversion_factor
+    cdef readonly object unit_name
+    cdef readonly object unit_auth_name
+    cdef readonly object unit_code
+    cdef readonly object unit_category
 
     @staticmethod
     cdef create(PJ_CONTEXT* projcontext, PJ* projobj, int param_idx)
 
 
 cdef class Grid:
-    cdef public object short_name
-    cdef public object full_name
-    cdef public object package_name
-    cdef public object url
-    cdef public object direct_download
-    cdef public object open_license
-    cdef public object available
+    cdef readonly object short_name
+    cdef readonly object full_name
+    cdef readonly object package_name
+    cdef readonly object url
+    cdef readonly object direct_download
+    cdef readonly object open_license
+    cdef readonly object available
 
     @staticmethod
     cdef create(PJ_CONTEXT* projcontext, PJ* projobj, int grid_idx)
 
 
 cdef class CoordinateOperation(Base):
-    cdef public object _params
-    cdef public object _grids
-    cdef public object method_name
-    cdef public object method_auth_name
-    cdef public object method_code
-    cdef public double accuracy
-    cdef public object is_instantiable
-    cdef public object has_ballpark_transformation
-    cdef public object _towgs84
+    cdef readonly object _params
+    cdef readonly object _grids
+    cdef readonly object method_name
+    cdef readonly object method_auth_name
+    cdef readonly object method_code
+    cdef readonly double accuracy
+    cdef readonly object is_instantiable
+    cdef readonly object has_ballpark_transformation
+    cdef readonly object _towgs84
 
     @staticmethod
     cdef create(PJ* coordinate_operation_pj)
@@ -110,8 +110,8 @@ cdef class _CRS(Base):
     cdef PJ_TYPE _type
     cdef PJ_PROJ_INFO projpj_info
     cdef char *pjinitstring
-    cdef public object srs
-    cdef public object type_name
+    cdef readonly object srs
+    cdef readonly object type_name
     cdef object _ellipsoid
     cdef object _area_of_use
     cdef object _prime_meridian

pyproj/_crs.pyx

@@ -39,6 +39,22 @@ def is_wkt(proj_string):
     return proj_context_guess_wkt_dialect(NULL, tmp_string) != PJ_GUESSED_NOT_WKT
 
 
+def is_proj(proj_string):
+    """
+    Check if the input projection string is in the PROJ format.
+
+    Parameters
+    ----------
+    proj_string: str
+        The projection string.
+
+    Returns
+    -------
+    bool: True if the string is in the PROJ format
+    """
+    return not is_wkt(proj_string) and "=" in proj_string
+
+
 cdef _to_wkt(PJ_CONTEXT* projctx, PJ* projobj, version=WktVersion.WKT2_2018, pretty=False):
     """
     Convert a PJ object to a wkt string.

pyproj/_geod.pxd

@@ -23,9 +23,9 @@ cdef extern from "geodesic.h":
 
 cdef class Geod:
     cdef geod_geodesic _geod_geodesic
-    cdef public object initstring
-    cdef public object a
-    cdef public object b
-    cdef public object f
-    cdef public object es
-    cdef public object sphere
+    cdef readonly object initstring
+    cdef readonly object a
+    cdef readonly object b
+    cdef readonly object f
+    cdef readonly object es
+    cdef readonly object sphere

pyproj/crs.py

@@ -26,6 +26,7 @@
     "Ellipsoid",
     "PrimeMeridian",
     "is_wkt",
+    "is_proj",
 ]
 
 import json
@@ -36,7 +37,7 @@
 from pyproj._crs import Datum  # noqa
 from pyproj._crs import Ellipsoid  # noqa
 from pyproj._crs import PrimeMeridian  # noqa
-from pyproj._crs import _CRS, is_wkt
+from pyproj._crs import _CRS, is_proj, is_wkt
 from pyproj.cf1x8 import (
     GRID_MAPPING_NAME_MAP,
     INVERSE_GRID_MAPPING_NAME_MAP,
@@ -81,7 +82,7 @@ def _prepare_from_string(in_crs_string):
         if not crs_dict:
             raise CRSError("CRS is empty JSON")
         return _prepare_from_dict(crs_dict)
-    elif not is_wkt(in_crs_string) and "=" in in_crs_string:
+    elif is_proj(in_crs_string):
         in_crs_string = re.sub(r"[\s+]?=[\s+]?", "=", in_crs_string.lstrip())
         # make sure the projection starts with +proj or +init
         starting_params = ("+init", "+proj", "init", "proj")
@@ -106,9 +107,6 @@ def _prepare_from_string(in_crs_string):
         # look for EPSG, replace with epsg (EPSG only works
         # on case-insensitive filesystems).
         in_crs_string = in_crs_string.replace("+init=EPSG", "+init=epsg").strip()
-        # remove no_defs as it does nothing as of PROJ 6.0.0 and breaks
-        # initialization with +init=epsg:...
-        in_crs_string = re.sub(r"\s\+?no_defs([\w=]+)?", "", in_crs_string)
         if in_crs_string.startswith(("+init", "init")):
             warnings.warn(
                 "'+init=<authority>:<code>' syntax is deprecated."
@@ -349,7 +347,7 @@ def from_proj4(cls, in_proj_string):
         -------
         CRS
         """
-        if is_wkt(in_proj_string) or "=" not in in_proj_string:
+        if not is_proj(in_proj_string):
             raise CRSError("Invalid PROJ string: {}".format(in_proj_string))
         return cls(_prepare_from_string(in_proj_string))
 
@@ -498,12 +496,13 @@ def parse(val):
                 val = [float(sval.strip()) for sval in val_split]
             return val
 
+        proj_string = self.to_proj4()
+        if proj_string is None:
+            return {}
+
         items = map(
             lambda kv: len(kv) == 2 and (kv[0], parse(kv[1])) or (kv[0], None),
-            (
-                part.lstrip("+").split("=", 1)
-                for part in self.to_proj4().strip().split()
-            ),
+            (part.lstrip("+").split("=", 1) for part in proj_string.strip().split()),
         )
 
         return {key: value for key, value in items if value is not False}

test/test_crs.py

@@ -800,24 +800,10 @@ def test_to_string__auth():
 def test_srs__no_plus():
     assert (
         CRS("proj=longlat datum=WGS84 no_defs").srs
-        == "proj=longlat datum=WGS84 type=crs"
+        == "proj=longlat datum=WGS84 no_defs type=crs"
     )
 
 
-@pytest.mark.parametrize(
-    "init_string, expected_srs",
-    [
-        ("+init=epsg:4326 +no_defs=True", "+init=epsg:4326 +type=crs"),
-        ("init=epsg:4326 no_defs=True", "init=epsg:4326 type=crs"),
-        ("+init=epsg:4326 +no_defs", "+init=epsg:4326 +type=crs"),
-        ("init=epsg:4326 no_defs", "init=epsg:4326 type=crs"),
-    ],
-)
-def test_removing_nodefs(init_string, expected_srs):
-    with pytest.warns(ProjDeprecationWarning):
-        assert CRS(init_string).srs == expected_srs
-
-
 def test_equals_different_type():
     assert CRS("epsg:4326") != ""
 
@@ -889,3 +875,19 @@ def test_whitepace_between_equals():
         "+proj=lcc +lat_1=30.0 +lat_2=35.0 +lat_0=30.0 "
         "+lon_0=87.0 +x_0=0 +y_0=0 +type=crs"
     )
+
+
+def test_to_dict_no_proj4():
+    crs = CRS(
+        {
+            "a": 6371229.0,
+            "b": 6371229.0,
+            "lon_0": -10.0,
+            "o_lat_p": 30.0,
+            "o_lon_p": 0.0,
+            "o_proj": "longlat",
+            "proj": "ob_tran",
+        }
+    )
+    assert crs.to_proj4() is None
+    assert crs.to_dict() == {}