From 2210bebeab7c87a4659f4c9fc5afaec5a2d9244f Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Tue, 5 Sep 2023 15:55:51 +0200
Subject: [PATCH 01/17] KDP-1761: Initial commit after running bump-pydantic

---
 src/covjson_pydantic/base_models.py       | 25 +++++++------
 src/covjson_pydantic/coverage.py          | 14 +++----
 src/covjson_pydantic/domain.py            | 45 ++++++++++++-----------
 src/covjson_pydantic/ndarray.py           |  8 ++--
 src/covjson_pydantic/observed_property.py |  8 ++--
 src/covjson_pydantic/parameter.py         | 25 +++++++------
 src/covjson_pydantic/reference_system.py  | 22 ++++++-----
 src/covjson_pydantic/unit.py              | 10 +++--
 8 files changed, 84 insertions(+), 73 deletions(-)

diff --git a/src/covjson_pydantic/base_models.py b/src/covjson_pydantic/base_models.py
index 3836e7b..06997a7 100644
--- a/src/covjson_pydantic/base_models.py
+++ b/src/covjson_pydantic/base_models.py
@@ -1,6 +1,6 @@
 import orjson
 from pydantic import BaseModel as PydanticBaseModel
-from pydantic import Extra
+from pydantic import ConfigDict
 
 
 def orjson_dumps(v, *, default, indent=None, sort_keys=False):
@@ -16,17 +16,18 @@ def orjson_dumps(v, *, default, indent=None, sort_keys=False):
 
 
 class BaseModel(PydanticBaseModel):
-    class Config:
-        anystr_strip_whitespace = True
-        min_anystr_length = 1
-        extra = Extra.forbid
-        validate_all = True
-        validate_assignment = True
-
-        json_loads = orjson.loads
-        json_dumps = orjson_dumps
+    # TODO[pydantic]: The following keys were removed: `json_loads`, `json_dumps`.
+    # Check https://docs.pydantic.dev/dev-v2/migration/#changes-to-config for more information.
+    model_config = ConfigDict(
+        str_strip_whitespace=True,
+        str_min_length=1,
+        extra="forbid",
+        validate_default=True,
+        validate_assignment=True,
+        json_loads=orjson.loads,
+        json_dumps=orjson_dumps,
+    )
 
 
 class CovJsonBaseModel(BaseModel):
-    class Config:
-        extra = Extra.allow  # allow custom members
+    model_config = ConfigDict(extra="allow")
diff --git a/src/covjson_pydantic/coverage.py b/src/covjson_pydantic/coverage.py
index 11d5fd4..2bcb9dc 100644
--- a/src/covjson_pydantic/coverage.py
+++ b/src/covjson_pydantic/coverage.py
@@ -17,18 +17,18 @@
 
 
 class Coverage(CovJsonBaseModel):
-    id: Optional[str]
+    id: Optional[str] = None
     type: Literal["Coverage"] = "Coverage"
     domain: Domain
-    parameters: Optional[Dict[str, Parameter]]
-    parameterGroups: Optional[List[ParameterGroup]]  # noqa: N815
+    parameters: Optional[Dict[str, Parameter]] = None
+    parameterGroups: Optional[List[ParameterGroup]] = None  # noqa: N815
     ranges: Dict[str, Union[NdArray, TiledNdArray, AnyUrl]]
 
 
 class CoverageCollection(CovJsonBaseModel):
     type: Literal["CoverageCollection"] = "CoverageCollection"
-    domainType: Optional[DomainType]  # noqa: N815
+    domainType: Optional[DomainType] = None  # noqa: N815
     coverages: List[Coverage]
-    parameters: Optional[Dict[str, Parameter]]
-    parameterGroups: Optional[List[ParameterGroup]]  # noqa: N815
-    referencing: Optional[List[ReferenceSystemConnectionObject]]
+    parameters: Optional[Dict[str, Parameter]] = None
+    parameterGroups: Optional[List[ParameterGroup]] = None  # noqa: N815
+    referencing: Optional[List[ReferenceSystemConnectionObject]] = None
diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index 8141393..5a4b635 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -8,10 +8,11 @@
 from typing import TypeVar
 from typing import Union
 
-from pydantic import Extra
+from pydantic import BaseModel
+from pydantic import ConfigDict
+from pydantic import model_validator
 from pydantic import PositiveInt
 from pydantic.class_validators import root_validator
-from pydantic.generics import GenericModel
 
 from .base_models import BaseModel
 from .base_models import CovJsonBaseModel
@@ -23,7 +24,8 @@ class CompactAxis(BaseModel):
     stop: float
     num: PositiveInt
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def single_value_case(cls, values):
         if values["num"] == 1 and values["start"] != values["stop"]:
             raise ValueError("If the value of 'num' is 1, then 'start' and 'stop' MUST have identical values.")
@@ -33,20 +35,17 @@ def single_value_case(cls, values):
 ValuesT = TypeVar("ValuesT")
 
 
-class ValuesAxis(GenericModel, Generic[ValuesT]):
+class ValuesAxis(BaseModel, Generic[ValuesT]):
     dataType: Optional[str]  # noqa: N815
     coordinates: Optional[List[str]]
     values: List[ValuesT]
     bounds: Optional[List[ValuesT]]
+    model_config = ConfigDict(
+        str_strip_whitespace=True, str_min_length=1, extra="allow", validate_default=True, validate_assignment=True
+    )
 
-    class Config:
-        anystr_strip_whitespace = True
-        min_anystr_length = 1
-        extra = Extra.allow  # allow custom members
-        validate_all = True
-        validate_assignment = True
-
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def bounds_length(cls, values):
         if values["bounds"] is not None and len(values["bounds"]) != 2 * len(values["values"]):
             raise ValueError("If provided, the length of 'bounds' should be twice that of 'values'.")
@@ -63,13 +62,14 @@ class DomainType(str, Enum):
 
 
 class Axes(BaseModel):
-    x: Optional[Union[ValuesAxis[float], CompactAxis]]
-    y: Optional[Union[ValuesAxis[float], CompactAxis]]
-    z: Optional[Union[ValuesAxis[float], CompactAxis]]
-    t: Optional[ValuesAxis[datetime]]
-    composite: Optional[ValuesAxis[Tuple]]
-
-    @root_validator(skip_on_failure=True)
+    x: Optional[Union[ValuesAxis[float], CompactAxis]] = None
+    y: Optional[Union[ValuesAxis[float], CompactAxis]] = None
+    z: Optional[Union[ValuesAxis[float], CompactAxis]] = None
+    t: Optional[ValuesAxis[datetime]] = None
+    composite: Optional[ValuesAxis[Tuple]] = None
+
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def at_least_one_axes(cls, values):
         if (
             values["x"] is None
@@ -84,9 +84,9 @@ def at_least_one_axes(cls, values):
 
 class Domain(CovJsonBaseModel):
     type: Literal["Domain"] = "Domain"
-    domainType: Optional[DomainType]  # noqa: N815
+    domainType: Optional[DomainType] = None  # noqa: N815
     axes: Axes
-    referencing: Optional[List[ReferenceSystemConnectionObject]]
+    referencing: Optional[List[ReferenceSystemConnectionObject]] = None
 
     @staticmethod
     def check_axis(domain_type, axes, required_axes, allowed_axes, single_value_axes):
@@ -119,7 +119,8 @@ def check_axis(domain_type, axes, required_axes, allowed_axes, single_value_axes
                         f"of a '{domain_type.value}' domain must contain a single value."
                     )
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def check_domain_consistent(cls, values):
         domain_type = values.get("domainType")
         axes = values.get("axes")
diff --git a/src/covjson_pydantic/ndarray.py b/src/covjson_pydantic/ndarray.py
index 068bb39..ac6127e 100644
--- a/src/covjson_pydantic/ndarray.py
+++ b/src/covjson_pydantic/ndarray.py
@@ -5,6 +5,7 @@
 from typing import Optional
 
 from pydantic import AnyUrl
+from pydantic import model_validator
 from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
@@ -19,11 +20,12 @@ class DataType(str, Enum):
 class NdArray(CovJsonBaseModel):
     type: Literal["NdArray"] = "NdArray"
     dataType: DataType = DataType.float  # noqa: N815
-    axisNames: Optional[List[str]]  # noqa: N815
-    shape: Optional[List[int]]
+    axisNames: Optional[List[str]] = None  # noqa: N815
+    shape: Optional[List[int]] = None
     values: List[Optional[float]]
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def check_field_dependencies(cls, values):
         if len(values["values"]) > 1 and (values.get("axisNames") is None or len(values.get("axisNames")) == 0):
             raise ValueError("'axisNames' must to be provided if array is not 0D")
diff --git a/src/covjson_pydantic/observed_property.py b/src/covjson_pydantic/observed_property.py
index f2f57f1..71a44e3 100644
--- a/src/covjson_pydantic/observed_property.py
+++ b/src/covjson_pydantic/observed_property.py
@@ -8,11 +8,11 @@
 class Category(BaseModel):
     id: str
     label: i18n
-    description: Optional[i18n]
+    description: Optional[i18n] = None
 
 
 class ObservedProperty(BaseModel):
-    id: Optional[str]
+    id: Optional[str] = None
     label: i18n
-    description: Optional[i18n]
-    categories: Optional[List[Category]]
+    description: Optional[i18n] = None
+    categories: Optional[List[Category]] = None
diff --git a/src/covjson_pydantic/parameter.py b/src/covjson_pydantic/parameter.py
index 63c0769..ea9b498 100644
--- a/src/covjson_pydantic/parameter.py
+++ b/src/covjson_pydantic/parameter.py
@@ -5,6 +5,7 @@
 from typing import Union
 
 from pydantic import Extra
+from pydantic import model_validator
 from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
@@ -15,14 +16,15 @@
 
 class Parameter(BaseModel, extra=Extra.allow):
     type: Literal["Parameter"] = "Parameter"
-    id: Optional[str]
-    label: Optional[i18n]
-    description: Optional[i18n]
+    id: Optional[str] = None
+    label: Optional[i18n] = None
+    description: Optional[i18n] = None
     observedProperty: ObservedProperty  # noqa: N815
-    categoryEncoding: Optional[Dict[str, Union[int, List[int]]]]  # noqa: N815
-    unit: Optional[Unit]
+    categoryEncoding: Optional[Dict[str, Union[int, List[int]]]] = None  # noqa: N815
+    unit: Optional[Unit] = None
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def must_not_have_unit_if_observed_property_has_categories(cls, values):
         if (
             values.get("unit") is not None
@@ -39,13 +41,14 @@ def must_not_have_unit_if_observed_property_has_categories(cls, values):
 
 class ParameterGroup(BaseModel, extra=Extra.allow):
     type: Literal["ParameterGroup"] = "ParameterGroup"
-    id: Optional[str]
-    label: Optional[i18n]
-    description: Optional[i18n]
-    observedProperty: Optional[ObservedProperty]  # noqa: N815
+    id: Optional[str] = None
+    label: Optional[i18n] = None
+    description: Optional[i18n] = None
+    observedProperty: Optional[ObservedProperty] = None  # noqa: N815
     members: List[str]
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def must_have_label_and_or_observed_property(cls, values):
         if values.get("label") is None and values.get("observedProperty") is None:
             raise ValueError(
diff --git a/src/covjson_pydantic/reference_system.py b/src/covjson_pydantic/reference_system.py
index ba6c795..eb16257 100644
--- a/src/covjson_pydantic/reference_system.py
+++ b/src/covjson_pydantic/reference_system.py
@@ -6,6 +6,7 @@
 
 from pydantic import AnyUrl
 from pydantic import Extra
+from pydantic import model_validator
 from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
@@ -13,26 +14,27 @@
 
 
 class TargetConcept(BaseModel):
-    id: Optional[str]  # Not in spec, but needed for example in spec for 'Identifier-based Reference Systems'
+    id: Optional[str] = None  # Not in spec, but needed for example in spec for 'Identifier-based Reference Systems'
     label: i18n
-    description: Optional[i18n]
+    description: Optional[i18n] = None
 
 
 class ReferenceSystem(BaseModel, extra=Extra.allow):
     type: Literal["GeographicCRS", "ProjectedCRS", "VerticalCRS", "TemporalRS", "IdentifierRS"]
-    id: Optional[str]
-    description: Optional[i18n]
+    id: Optional[str] = None
+    description: Optional[i18n] = None
 
     # Only for TemporalRS
-    calendar: Optional[Union[Literal["Gregorian"], AnyUrl]]
-    timeScale: Optional[AnyUrl]  # noqa: N815
+    calendar: Optional[Union[Literal["Gregorian"], AnyUrl]] = None
+    timeScale: Optional[AnyUrl] = None  # noqa: N815
 
     # Only for IdentifierRS
-    label: Optional[i18n]
-    targetConcept: Optional[TargetConcept]  # noqa: N815
-    identifiers: Optional[Dict[str, TargetConcept]]
+    label: Optional[i18n] = None
+    targetConcept: Optional[TargetConcept] = None  # noqa: N815
+    identifiers: Optional[Dict[str, TargetConcept]] = None
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def check_type_specific_fields(cls, values):
         if values["type"] != "TemporalRS" and (
             values.get("calendar") is not None or values.get("timeScale") is not None
diff --git a/src/covjson_pydantic/unit.py b/src/covjson_pydantic/unit.py
index f4a8a44..5c7ab8b 100644
--- a/src/covjson_pydantic/unit.py
+++ b/src/covjson_pydantic/unit.py
@@ -1,6 +1,7 @@
 from typing import Optional
 from typing import Union
 
+from pydantic import model_validator
 from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
@@ -13,11 +14,12 @@ class Symbol(BaseModel):
 
 
 class Unit(BaseModel):
-    id: Optional[str]
-    label: Optional[i18n]
-    symbol: Optional[Union[str, Symbol]]
+    id: Optional[str] = None
+    label: Optional[i18n] = None
+    symbol: Optional[Union[str, Symbol]] = None
 
-    @root_validator(skip_on_failure=True)
+    @model_validator(skip_on_failure=True)
+    @classmethod
     def check_either_label_or_symbol(cls, values):
         if values.get("label") is None and values.get("symbol") is None:
             raise ValueError("Either 'label' or 'symbol' should be set")

From c7701429375b876458ad6ffba173c328cf990fe9 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 13:45:33 +0200
Subject: [PATCH 02/17] KDP-1761: Fix validators. Remove orjson.

---
 example.py                               |  2 +-
 pyproject.toml                           |  2 +-
 src/covjson_pydantic/base_models.py      | 16 --------
 src/covjson_pydantic/domain.py           | 52 +++++++++---------------
 src/covjson_pydantic/ndarray.py          | 24 ++++-------
 src/covjson_pydantic/parameter.py        | 23 ++++-------
 src/covjson_pydantic/reference_system.py | 20 ++++-----
 src/covjson_pydantic/unit.py             | 10 ++---
 8 files changed, 50 insertions(+), 99 deletions(-)

diff --git a/example.py b/example.py
index 238b4a2..d5d96f6 100644
--- a/example.py
+++ b/example.py
@@ -16,4 +16,4 @@
     ranges={"temperature": NdArray(axisNames=["x", "y", "t"], shape=[1, 1, 1], values=[42.0])},
 )
 
-print(c.json(exclude_none=True, indent=True))
+print(c.model_dump_json(exclude_none=True, indent=4))
diff --git a/pyproject.toml b/pyproject.toml
index 0f2e3eb..5e4e132 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,7 @@ classifiers = [
     "Typing :: Typed",
 ]
 version = "0.1.0"
-dependencies = ["pydantic>=1,<2", "orjson>=3"]
+dependencies = ["pydantic>=2,<3"]
 
 [project.optional-dependencies]
 test = ["pytest", "pytest-cov"]
diff --git a/src/covjson_pydantic/base_models.py b/src/covjson_pydantic/base_models.py
index 06997a7..d010d11 100644
--- a/src/covjson_pydantic/base_models.py
+++ b/src/covjson_pydantic/base_models.py
@@ -1,22 +1,8 @@
-import orjson
 from pydantic import BaseModel as PydanticBaseModel
 from pydantic import ConfigDict
 
 
-def orjson_dumps(v, *, default, indent=None, sort_keys=False):
-    options = orjson.OPT_NON_STR_KEYS | orjson.OPT_UTC_Z | orjson.OPT_NAIVE_UTC
-    if indent:
-        options |= orjson.OPT_INDENT_2
-
-    if sort_keys:
-        options |= orjson.OPT_SORT_KEYS
-
-    # orjson.dumps returns bytes, to match standard json.dumps we need to decode
-    return orjson.dumps(v, default=default, option=options).decode()
-
-
 class BaseModel(PydanticBaseModel):
-    # TODO[pydantic]: The following keys were removed: `json_loads`, `json_dumps`.
     # Check https://docs.pydantic.dev/dev-v2/migration/#changes-to-config for more information.
     model_config = ConfigDict(
         str_strip_whitespace=True,
@@ -24,8 +10,6 @@ class BaseModel(PydanticBaseModel):
         extra="forbid",
         validate_default=True,
         validate_assignment=True,
-        json_loads=orjson.loads,
-        json_dumps=orjson_dumps,
     )
 
 
diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index 5a4b635..a735f0e 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -8,11 +8,9 @@
 from typing import TypeVar
 from typing import Union
 
-from pydantic import BaseModel
 from pydantic import ConfigDict
 from pydantic import model_validator
 from pydantic import PositiveInt
-from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
 from .base_models import CovJsonBaseModel
@@ -24,32 +22,30 @@ class CompactAxis(BaseModel):
     stop: float
     num: PositiveInt
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def single_value_case(cls, values):
-        if values["num"] == 1 and values["start"] != values["stop"]:
+    @model_validator(mode="after")
+    def single_value_case(self):
+        if self.num == 1 and self.start != self.stop:
             raise ValueError("If the value of 'num' is 1, then 'start' and 'stop' MUST have identical values.")
-        return values
+        return self
 
 
 ValuesT = TypeVar("ValuesT")
 
 
 class ValuesAxis(BaseModel, Generic[ValuesT]):
-    dataType: Optional[str]  # noqa: N815
-    coordinates: Optional[List[str]]
+    dataType: Optional[str] = None  # noqa: N815
+    coordinates: Optional[List[str]] = None
     values: List[ValuesT]
-    bounds: Optional[List[ValuesT]]
+    bounds: Optional[List[ValuesT]] = None
     model_config = ConfigDict(
         str_strip_whitespace=True, str_min_length=1, extra="allow", validate_default=True, validate_assignment=True
     )
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def bounds_length(cls, values):
-        if values["bounds"] is not None and len(values["bounds"]) != 2 * len(values["values"]):
+    @model_validator(mode="after")
+    def bounds_length(self):
+        if self.bounds is not None and len(self.bounds) != 2 * len(self.values):
             raise ValueError("If provided, the length of 'bounds' should be twice that of 'values'.")
-        return values
+        return self
 
 
 class DomainType(str, Enum):
@@ -68,18 +64,11 @@ class Axes(BaseModel):
     t: Optional[ValuesAxis[datetime]] = None
     composite: Optional[ValuesAxis[Tuple]] = None
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def at_least_one_axes(cls, values):
-        if (
-            values["x"] is None
-            and values["y"] is None
-            and values["z"] is None
-            and values["t"] is None
-            and values["composite"] is None
-        ):
+    @model_validator(mode="after")
+    def at_least_one_axes(self):
+        if self.x is None and self.y is None and self.z is None and self.t is None and self.composite is None:
             raise ValueError("At least one axis of x,y,z,t or composite must be given.")
-        return values
+        return self
 
 
 class Domain(CovJsonBaseModel):
@@ -119,11 +108,10 @@ def check_axis(domain_type, axes, required_axes, allowed_axes, single_value_axes
                         f"of a '{domain_type.value}' domain must contain a single value."
                     )
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def check_domain_consistent(cls, values):
-        domain_type = values.get("domainType")
-        axes = values.get("axes")
+    @model_validator(mode="after")
+    def check_domain_consistent(self):
+        domain_type = self.domainType
+        axes = self.axes
 
         if domain_type == DomainType.grid:
             Domain.check_axis(
@@ -159,4 +147,4 @@ def check_domain_consistent(cls, values):
                 domain_type, axes, required_axes={"composite"}, allowed_axes={"t"}, single_value_axes={"t"}
             )
 
-        return values
+        return self
diff --git a/src/covjson_pydantic/ndarray.py b/src/covjson_pydantic/ndarray.py
index ac6127e..a65e79c 100644
--- a/src/covjson_pydantic/ndarray.py
+++ b/src/covjson_pydantic/ndarray.py
@@ -6,7 +6,6 @@
 
 from pydantic import AnyUrl
 from pydantic import model_validator
-from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
 from .base_models import CovJsonBaseModel
@@ -24,31 +23,26 @@ class NdArray(CovJsonBaseModel):
     shape: Optional[List[int]] = None
     values: List[Optional[float]]
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def check_field_dependencies(cls, values):
-        if len(values["values"]) > 1 and (values.get("axisNames") is None or len(values.get("axisNames")) == 0):
+    @model_validator(mode="after")
+    def check_field_dependencies(self):
+        if len(self.values) > 1 and (self.axisNames is None or len(self.axisNames) == 0):
             raise ValueError("'axisNames' must to be provided if array is not 0D")
 
-        if len(values["values"]) > 1 and (values.get("shape") is None or len(values.get("shape")) == 0):
+        if len(self.values) > 1 and (self.shape is None or len(self.shape) == 0):
             raise ValueError("'shape' must to be provided if array is not 0D")
 
-        if (
-            values.get("axisNames") is not None
-            and values.get("shape") is not None
-            and len(values.get("axisNames")) != len(values.get("shape"))
-        ):
+        if self.axisNames is not None and self.shape is not None and len(self.axisNames) != len(self.shape):
             raise ValueError("'axisNames' and 'shape' should have equal length")
 
-        if values.get("shape") is not None and len(values.get("shape")) >= 1:
-            prod = math.prod(values["shape"])
-            if len(values["values"]) != prod:
+        if self.shape is not None and len(self.shape) >= 1:
+            prod = math.prod(self.shape)
+            if len(self.values) != prod:
                 raise ValueError(
                     "Where 'shape' is present and non-empty, the product of its values MUST equal "
                     "the number of elements in the 'values' array."
                 )
 
-        return values
+        return self
 
 
 class TileSet(BaseModel):
diff --git a/src/covjson_pydantic/parameter.py b/src/covjson_pydantic/parameter.py
index ea9b498..7b578ed 100644
--- a/src/covjson_pydantic/parameter.py
+++ b/src/covjson_pydantic/parameter.py
@@ -6,7 +6,6 @@
 
 from pydantic import Extra
 from pydantic import model_validator
-from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
 from .i18n import i18n
@@ -23,20 +22,15 @@ class Parameter(BaseModel, extra=Extra.allow):
     categoryEncoding: Optional[Dict[str, Union[int, List[int]]]] = None  # noqa: N815
     unit: Optional[Unit] = None
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def must_not_have_unit_if_observed_property_has_categories(cls, values):
-        if (
-            values.get("unit") is not None
-            and values.get("observedProperty") is not None
-            and values.get("observedProperty").categories is not None
-        ):
+    @model_validator(mode="after")
+    def must_not_have_unit_if_observed_property_has_categories(self):
+        if self.unit is not None and self.observedProperty is not None and self.observedProperty.categories is not None:
             raise ValueError(
                 "A parameter object MUST NOT have a 'unit' member "
                 "if the 'observedProperty' member has a 'categories' member."
             )
 
-        return values
+        return self
 
 
 class ParameterGroup(BaseModel, extra=Extra.allow):
@@ -47,11 +41,10 @@ class ParameterGroup(BaseModel, extra=Extra.allow):
     observedProperty: Optional[ObservedProperty] = None  # noqa: N815
     members: List[str]
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def must_have_label_and_or_observed_property(cls, values):
-        if values.get("label") is None and values.get("observedProperty") is None:
+    @model_validator(mode="after")
+    def must_have_label_and_or_observed_property(self):
+        if self.label is None and self.observedProperty is None:
             raise ValueError(
                 "A parameter group object MUST have either or both the members 'label' or/and 'observedProperty'"
             )
-        return values
+        return self
diff --git a/src/covjson_pydantic/reference_system.py b/src/covjson_pydantic/reference_system.py
index eb16257..9aaca94 100644
--- a/src/covjson_pydantic/reference_system.py
+++ b/src/covjson_pydantic/reference_system.py
@@ -7,7 +7,6 @@
 from pydantic import AnyUrl
 from pydantic import Extra
 from pydantic import model_validator
-from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
 from .i18n import i18n
@@ -33,27 +32,22 @@ class ReferenceSystem(BaseModel, extra=Extra.allow):
     targetConcept: Optional[TargetConcept] = None  # noqa: N815
     identifiers: Optional[Dict[str, TargetConcept]] = None
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def check_type_specific_fields(cls, values):
-        if values["type"] != "TemporalRS" and (
-            values.get("calendar") is not None or values.get("timeScale") is not None
-        ):
+    @model_validator(mode="after")
+    def check_type_specific_fields(self):
+        if self.type != "TemporalRS" and (self.calendar is not None or self.timeScale is not None):
             raise ValueError("'calendar' and 'timeScale' fields can only be used for type 'TemporalRS'")
 
-        if values["type"] != "IdentifierRS" and (
-            values.get("label") is not None
-            or values.get("targetConcept") is not None
-            or values.get("identifiers") is not None
+        if self.type != "IdentifierRS" and (
+            self.label is not None or self.targetConcept is not None or self.identifiers is not None
         ):
             raise ValueError(
                 "'label', 'targetConcept' and 'identifiers' fields can only be used for type 'IdentifierRS'"
             )
 
-        if values["type"] == "IdentifierRS" and values.get("targetConcept") is None:
+        if self.type == "IdentifierRS" and self.targetConcept is None:
             raise ValueError("An identifier RS object MUST have a member 'targetConcept'")
 
-        return values
+        return self
 
 
 class ReferenceSystemConnectionObject(BaseModel):
diff --git a/src/covjson_pydantic/unit.py b/src/covjson_pydantic/unit.py
index 5c7ab8b..63ac5a7 100644
--- a/src/covjson_pydantic/unit.py
+++ b/src/covjson_pydantic/unit.py
@@ -2,7 +2,6 @@
 from typing import Union
 
 from pydantic import model_validator
-from pydantic.class_validators import root_validator
 
 from .base_models import BaseModel
 from .i18n import i18n
@@ -18,10 +17,9 @@ class Unit(BaseModel):
     label: Optional[i18n] = None
     symbol: Optional[Union[str, Symbol]] = None
 
-    @model_validator(skip_on_failure=True)
-    @classmethod
-    def check_either_label_or_symbol(cls, values):
-        if values.get("label") is None and values.get("symbol") is None:
+    @model_validator(mode="after")
+    def check_either_label_or_symbol(self):
+        if self.label is None and self.symbol is None:
             raise ValueError("Either 'label' or 'symbol' should be set")
 
-        return values
+        return self

From d92ccfe32ff67a689c82429d653bf15ac1de8740 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 13:46:46 +0200
Subject: [PATCH 03/17] KDP-1761: Remove comment

---
 src/covjson_pydantic/base_models.py | 1 -
 1 file changed, 1 deletion(-)

diff --git a/src/covjson_pydantic/base_models.py b/src/covjson_pydantic/base_models.py
index d010d11..7511afe 100644
--- a/src/covjson_pydantic/base_models.py
+++ b/src/covjson_pydantic/base_models.py
@@ -3,7 +3,6 @@
 
 
 class BaseModel(PydanticBaseModel):
-    # Check https://docs.pydantic.dev/dev-v2/migration/#changes-to-config for more information.
     model_config = ConfigDict(
         str_strip_whitespace=True,
         str_min_length=1,

From 1c995fd00cbd54b0cb0b3617d31856098aa3f8a4 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 14:08:48 +0200
Subject: [PATCH 04/17] KDP-1761: Fix testing

---
 src/covjson_pydantic/ndarray.py          | 3 +--
 src/covjson_pydantic/parameter.py        | 5 ++---
 src/covjson_pydantic/reference_system.py | 3 +--
 tests/test_coverage.py                   | 4 ++--
 4 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/src/covjson_pydantic/ndarray.py b/src/covjson_pydantic/ndarray.py
index a65e79c..274a30f 100644
--- a/src/covjson_pydantic/ndarray.py
+++ b/src/covjson_pydantic/ndarray.py
@@ -4,7 +4,6 @@
 from typing import Literal
 from typing import Optional
 
-from pydantic import AnyUrl
 from pydantic import model_validator
 
 from .base_models import BaseModel
@@ -47,7 +46,7 @@ def check_field_dependencies(self):
 
 class TileSet(BaseModel):
     tileShape: List[Optional[int]]  # noqa: N815
-    urlTemplate: AnyUrl  # noqa: N815
+    urlTemplate: str  # noqa: N815
 
 
 # TODO: Validation of field dependencies
diff --git a/src/covjson_pydantic/parameter.py b/src/covjson_pydantic/parameter.py
index 7b578ed..25b5645 100644
--- a/src/covjson_pydantic/parameter.py
+++ b/src/covjson_pydantic/parameter.py
@@ -4,7 +4,6 @@
 from typing import Optional
 from typing import Union
 
-from pydantic import Extra
 from pydantic import model_validator
 
 from .base_models import BaseModel
@@ -13,7 +12,7 @@
 from .unit import Unit
 
 
-class Parameter(BaseModel, extra=Extra.allow):
+class Parameter(BaseModel, extra="allow"):
     type: Literal["Parameter"] = "Parameter"
     id: Optional[str] = None
     label: Optional[i18n] = None
@@ -33,7 +32,7 @@ def must_not_have_unit_if_observed_property_has_categories(self):
         return self
 
 
-class ParameterGroup(BaseModel, extra=Extra.allow):
+class ParameterGroup(BaseModel, extra="allow"):
     type: Literal["ParameterGroup"] = "ParameterGroup"
     id: Optional[str] = None
     label: Optional[i18n] = None
diff --git a/src/covjson_pydantic/reference_system.py b/src/covjson_pydantic/reference_system.py
index 9aaca94..570610a 100644
--- a/src/covjson_pydantic/reference_system.py
+++ b/src/covjson_pydantic/reference_system.py
@@ -5,7 +5,6 @@
 from typing import Union
 
 from pydantic import AnyUrl
-from pydantic import Extra
 from pydantic import model_validator
 
 from .base_models import BaseModel
@@ -18,7 +17,7 @@ class TargetConcept(BaseModel):
     description: Optional[i18n] = None
 
 
-class ReferenceSystem(BaseModel, extra=Extra.allow):
+class ReferenceSystem(BaseModel, extra="allow"):
     type: Literal["GeographicCRS", "ProjectedCRS", "VerticalCRS", "TemporalRS", "IdentifierRS"]
     id: Optional[str] = None
     description: Optional[i18n] = None
diff --git a/tests/test_coverage.py b/tests/test_coverage.py
index fdfc296..139872b 100644
--- a/tests/test_coverage.py
+++ b/tests/test_coverage.py
@@ -47,7 +47,7 @@ def test_happy_cases(file_name, object_type):
     json_string = json.dumps(data, separators=(",", ":"))
 
     # Round-trip
-    assert object_type.parse_raw(json_string).json(exclude_none=True) == json_string
+    assert object_type.model_validate_json(json_string).model_dump_json(exclude_none=True) == json_string
 
 
 error_cases = [
@@ -70,4 +70,4 @@ def test_error_cases(file_name, object_type, error_message):
     json_string = json.dumps(data, separators=(",", ":"))
 
     with pytest.raises(ValidationError, match=error_message):
-        object_type.parse_raw(json_string)
+        object_type.model_validate_json(json_string)

From 3c02d03ef2956b175d103c7af2812f6407d0c3ec Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 16:10:47 +0200
Subject: [PATCH 05/17] KDP-1761: Ignored warning for i18n type

---
 src/covjson_pydantic/i18n.py | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/covjson_pydantic/i18n.py b/src/covjson_pydantic/i18n.py
index 2cc6e0b..87035f6 100644
--- a/src/covjson_pydantic/i18n.py
+++ b/src/covjson_pydantic/i18n.py
@@ -9,4 +9,9 @@ class LanguageTag(str, Enum):
     undefined = "und"
 
 
-i18n = Dict[LanguageTag, str]
+# TODO: This was throwing warning:
+#   Expected `definition-ref` but got `LanguageTag` - serialized value may not be as expected
+# This may be a bug in Pydantic: https://github.com/pydantic/pydantic/issues/6467
+# So, for now, reverted to a less strict type
+# i18n = Dict[LanguageTag, str]
+i18n = Dict[str, str]

From 5907c4e5464155e0e6d7028fb9648dd0afbd702d Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 16:25:23 +0200
Subject: [PATCH 06/17] KDP-1761: Upgrade mypy

---
 .pre-commit-config.yaml | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 40eda99..ed5aa23 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -53,7 +53,7 @@ repos:
         additional_dependencies: [ 'pep8-naming==0.12.1' ]
 
   - repo: https://github.com/pre-commit/mirrors-mypy
-    rev: v0.971
+    rev: v1.5.1
     hooks:
       - id: mypy
         language_version: python
@@ -64,5 +64,4 @@ repos:
         # Don't pass it the individual filenames because it is already doing the whole folder.
         pass_filenames: false
         additional_dependencies:
-          - orjson
           - pydantic

From c8e70a39868578082a6fcc593ae0bf6d5e610e97 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 16:25:52 +0200
Subject: [PATCH 07/17] KDP-1761: Force t-axis to be timezone aware

---
 example.py                     | 5 +++--
 src/covjson_pydantic/domain.py | 4 ++--
 2 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/example.py b/example.py
index d5d96f6..32140ae 100644
--- a/example.py
+++ b/example.py
@@ -1,4 +1,5 @@
-import datetime
+from datetime import datetime
+from datetime import timezone
 
 from covjson_pydantic.coverage import Coverage
 from covjson_pydantic.domain import Domain
@@ -10,7 +11,7 @@
         axes={
             "x": {"dataType": "float", "values": [1.23]},
             "y": {"values": [4.56]},
-            "t": {"dataType": "datetime", "values": [datetime.datetime.now()]},
+            "t": {"dataType": "datetime", "values": [datetime.now(tz=timezone.utc)]},
         },
     ),
     ranges={"temperature": NdArray(axisNames=["x", "y", "t"], shape=[1, 1, 1], values=[42.0])},
diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index a735f0e..c59a51a 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -1,4 +1,3 @@
-from datetime import datetime
 from enum import Enum
 from typing import Generic
 from typing import List
@@ -8,6 +7,7 @@
 from typing import TypeVar
 from typing import Union
 
+from pydantic import AwareDatetime
 from pydantic import ConfigDict
 from pydantic import model_validator
 from pydantic import PositiveInt
@@ -61,7 +61,7 @@ class Axes(BaseModel):
     x: Optional[Union[ValuesAxis[float], CompactAxis]] = None
     y: Optional[Union[ValuesAxis[float], CompactAxis]] = None
     z: Optional[Union[ValuesAxis[float], CompactAxis]] = None
-    t: Optional[ValuesAxis[datetime]] = None
+    t: Optional[ValuesAxis[AwareDatetime]] = None
     composite: Optional[ValuesAxis[Tuple]] = None
 
     @model_validator(mode="after")

From 5042ecfe9f2b496195f92d5470819482e0670e3a Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 16:34:05 +0200
Subject: [PATCH 08/17] KDP-1761: Update README

---
 README.md | 9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/README.md b/README.md
index 5911298..fb926a6 100644
--- a/README.md
+++ b/README.md
@@ -35,7 +35,7 @@ pip install git+https://github.com/KNMI/covjson-pydantic.git
 ## Usage
 
 ```python
-import datetime
+from datetime import datetime, timezone
 from covjson_pydantic.coverage import Coverage
 from covjson_pydantic.domain import Domain
 from covjson_pydantic.ndarray import NdArray
@@ -46,14 +46,15 @@ c = Coverage(
         axes={
             "x": {"dataType": "float", "values": [1.23]},
             "y": {"values": [4.56]},
-            "t": {"dataType": "datetime", "values": [datetime.datetime.now()]}
+            "t": {"dataType": "datetime", "values": [datetime.now(tz=timezone.utc)]},
         },
     ),
     ranges={
         "temperature": NdArray(axisNames=["x", "y", "t"], shape=[1, 1, 1], values=[42.0])
     }
 )
-print(c.json(exclude_none=True,indent=True))
+
+print(c.model_dump_json(exclude_none=True, indent=4))
 ```
 Will print
 ```json
@@ -77,7 +78,7 @@ Will print
             "t": {
                 "dataType": "datetime",
                 "values": [
-                    "2023-01-19T13:14:47.126631Z"
+                    "2023-09-08T14:31:41.311717Z"
                 ]
             }
         }

From 8038695f1d8cd1dcadd342b3e848b3a819a9b02b Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 8 Sep 2023 16:42:55 +0200
Subject: [PATCH 09/17] KDP-1761: Bump version

---
 pyproject.toml               | 2 +-
 src/covjson_pydantic/i18n.py | 1 +
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 5e4e132..8bb9666 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,7 +19,7 @@ classifiers = [
     "Topic :: Scientific/Engineering :: GIS",
     "Typing :: Typed",
 ]
-version = "0.1.0"
+version = "0.2.0"
 dependencies = ["pydantic>=2,<3"]
 
 [project.optional-dependencies]
diff --git a/src/covjson_pydantic/i18n.py b/src/covjson_pydantic/i18n.py
index 87035f6..4959b37 100644
--- a/src/covjson_pydantic/i18n.py
+++ b/src/covjson_pydantic/i18n.py
@@ -12,6 +12,7 @@ class LanguageTag(str, Enum):
 # TODO: This was throwing warning:
 #   Expected `definition-ref` but got `LanguageTag` - serialized value may not be as expected
 # This may be a bug in Pydantic: https://github.com/pydantic/pydantic/issues/6467
+# or: https://github.com/pydantic/pydantic/issues/6422
 # So, for now, reverted to a less strict type
 # i18n = Dict[LanguageTag, str]
 i18n = Dict[str, str]

From 724856a2359d4e95f8f05efdbd45abd5def7b45e Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Thu, 14 Sep 2023 13:57:35 +0200
Subject: [PATCH 10/17] KDP-1761: Fix example

---
 README.md  | 17 ++++++++---------
 example.py | 13 ++++++++-----
 2 files changed, 16 insertions(+), 14 deletions(-)

diff --git a/README.md b/README.md
index fb926a6..e21b373 100644
--- a/README.md
+++ b/README.md
@@ -36,18 +36,19 @@ pip install git+https://github.com/KNMI/covjson-pydantic.git
 
 ```python
 from datetime import datetime, timezone
+from pydantic import AwareDatetime
 from covjson_pydantic.coverage import Coverage
-from covjson_pydantic.domain import Domain
+from covjson_pydantic.domain import Domain, Axes, ValuesAxis
 from covjson_pydantic.ndarray import NdArray
 
 c = Coverage(
     domain=Domain(
         domainType="PointSeries",
-        axes={
-            "x": {"dataType": "float", "values": [1.23]},
-            "y": {"values": [4.56]},
-            "t": {"dataType": "datetime", "values": [datetime.now(tz=timezone.utc)]},
-        },
+        axes=Axes(
+            x=ValuesAxis[float](values=[1.23]),
+            y=ValuesAxis[float](values=[4.56]),
+            t=ValuesAxis[AwareDatetime](values=[datetime.now(tz=timezone.utc)])
+        )
     ),
     ranges={
         "temperature": NdArray(axisNames=["x", "y", "t"], shape=[1, 1, 1], values=[42.0])
@@ -65,7 +66,6 @@ Will print
         "domainType": "PointSeries",
         "axes": {
             "x": {
-                "dataType": "float",
                 "values": [
                     1.23
                 ]
@@ -76,9 +76,8 @@ Will print
                 ]
             },
             "t": {
-                "dataType": "datetime",
                 "values": [
-                    "2023-09-08T14:31:41.311717Z"
+                    "2023-09-14T11:54:02.151493Z"
                 ]
             }
         }
diff --git a/example.py b/example.py
index 32140ae..bb4d902 100644
--- a/example.py
+++ b/example.py
@@ -2,17 +2,20 @@
 from datetime import timezone
 
 from covjson_pydantic.coverage import Coverage
+from covjson_pydantic.domain import Axes
 from covjson_pydantic.domain import Domain
+from covjson_pydantic.domain import ValuesAxis
 from covjson_pydantic.ndarray import NdArray
+from pydantic import AwareDatetime
 
 c = Coverage(
     domain=Domain(
         domainType="PointSeries",
-        axes={
-            "x": {"dataType": "float", "values": [1.23]},
-            "y": {"values": [4.56]},
-            "t": {"dataType": "datetime", "values": [datetime.now(tz=timezone.utc)]},
-        },
+        axes=Axes(
+            x=ValuesAxis[float](values=[1.23]),
+            y=ValuesAxis[float](values=[4.56]),
+            t=ValuesAxis[AwareDatetime](values=[datetime.now(tz=timezone.utc)]),
+        ),
     ),
     ranges={"temperature": NdArray(axisNames=["x", "y", "t"], shape=[1, 1, 1], values=[42.0])},
 )

From e1d0f19019002ecc21e33533e16286db921c1535 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Thu, 21 Sep 2023 08:50:16 +0200
Subject: [PATCH 11/17] KDP-1761: Simplify usage of the base models

---
 src/covjson_pydantic/base_models.py       |  6 +-----
 src/covjson_pydantic/coverage.py          |  4 ++--
 src/covjson_pydantic/domain.py            | 11 +++--------
 src/covjson_pydantic/ndarray.py           |  7 +++----
 src/covjson_pydantic/observed_property.py |  6 +++---
 src/covjson_pydantic/parameter.py         |  6 +++---
 src/covjson_pydantic/reference_system.py  |  8 ++++----
 src/covjson_pydantic/unit.py              |  6 +++---
 8 files changed, 22 insertions(+), 32 deletions(-)

diff --git a/src/covjson_pydantic/base_models.py b/src/covjson_pydantic/base_models.py
index 7511afe..b5e68af 100644
--- a/src/covjson_pydantic/base_models.py
+++ b/src/covjson_pydantic/base_models.py
@@ -2,7 +2,7 @@
 from pydantic import ConfigDict
 
 
-class BaseModel(PydanticBaseModel):
+class CovJsonBaseModel(PydanticBaseModel):
     model_config = ConfigDict(
         str_strip_whitespace=True,
         str_min_length=1,
@@ -10,7 +10,3 @@ class BaseModel(PydanticBaseModel):
         validate_default=True,
         validate_assignment=True,
     )
-
-
-class CovJsonBaseModel(BaseModel):
-    model_config = ConfigDict(extra="allow")
diff --git a/src/covjson_pydantic/coverage.py b/src/covjson_pydantic/coverage.py
index 2bcb9dc..279240b 100644
--- a/src/covjson_pydantic/coverage.py
+++ b/src/covjson_pydantic/coverage.py
@@ -16,7 +16,7 @@
 from .reference_system import ReferenceSystemConnectionObject
 
 
-class Coverage(CovJsonBaseModel):
+class Coverage(CovJsonBaseModel, extra="allow"):
     id: Optional[str] = None
     type: Literal["Coverage"] = "Coverage"
     domain: Domain
@@ -25,7 +25,7 @@ class Coverage(CovJsonBaseModel):
     ranges: Dict[str, Union[NdArray, TiledNdArray, AnyUrl]]
 
 
-class CoverageCollection(CovJsonBaseModel):
+class CoverageCollection(CovJsonBaseModel, extra="allow"):
     type: Literal["CoverageCollection"] = "CoverageCollection"
     domainType: Optional[DomainType] = None  # noqa: N815
     coverages: List[Coverage]
diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index c59a51a..cde31f4 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -8,16 +8,14 @@
 from typing import Union
 
 from pydantic import AwareDatetime
-from pydantic import ConfigDict
 from pydantic import model_validator
 from pydantic import PositiveInt
 
-from .base_models import BaseModel
 from .base_models import CovJsonBaseModel
 from .reference_system import ReferenceSystemConnectionObject
 
 
-class CompactAxis(BaseModel):
+class CompactAxis(CovJsonBaseModel):
     start: float
     stop: float
     num: PositiveInt
@@ -32,14 +30,11 @@ def single_value_case(self):
 ValuesT = TypeVar("ValuesT")
 
 
-class ValuesAxis(BaseModel, Generic[ValuesT]):
+class ValuesAxis(CovJsonBaseModel, Generic[ValuesT], extra="allow"):
     dataType: Optional[str] = None  # noqa: N815
     coordinates: Optional[List[str]] = None
     values: List[ValuesT]
     bounds: Optional[List[ValuesT]] = None
-    model_config = ConfigDict(
-        str_strip_whitespace=True, str_min_length=1, extra="allow", validate_default=True, validate_assignment=True
-    )
 
     @model_validator(mode="after")
     def bounds_length(self):
@@ -57,7 +52,7 @@ class DomainType(str, Enum):
     multi_point = "MultiPoint"
 
 
-class Axes(BaseModel):
+class Axes(CovJsonBaseModel):
     x: Optional[Union[ValuesAxis[float], CompactAxis]] = None
     y: Optional[Union[ValuesAxis[float], CompactAxis]] = None
     z: Optional[Union[ValuesAxis[float], CompactAxis]] = None
diff --git a/src/covjson_pydantic/ndarray.py b/src/covjson_pydantic/ndarray.py
index 274a30f..abda788 100644
--- a/src/covjson_pydantic/ndarray.py
+++ b/src/covjson_pydantic/ndarray.py
@@ -6,7 +6,6 @@
 
 from pydantic import model_validator
 
-from .base_models import BaseModel
 from .base_models import CovJsonBaseModel
 
 
@@ -15,7 +14,7 @@ class DataType(str, Enum):
     float = "float"
 
 
-class NdArray(CovJsonBaseModel):
+class NdArray(CovJsonBaseModel, extra="allow"):
     type: Literal["NdArray"] = "NdArray"
     dataType: DataType = DataType.float  # noqa: N815
     axisNames: Optional[List[str]] = None  # noqa: N815
@@ -44,13 +43,13 @@ def check_field_dependencies(self):
         return self
 
 
-class TileSet(BaseModel):
+class TileSet(CovJsonBaseModel):
     tileShape: List[Optional[int]]  # noqa: N815
     urlTemplate: str  # noqa: N815
 
 
 # TODO: Validation of field dependencies
-class TiledNdArray(CovJsonBaseModel):
+class TiledNdArray(CovJsonBaseModel, extra="allow"):
     type: Literal["TiledNdArray"] = "TiledNdArray"
     dataType: DataType = DataType.float  # noqa: N815
     axisNames: List[str]  # noqa: N815
diff --git a/src/covjson_pydantic/observed_property.py b/src/covjson_pydantic/observed_property.py
index 71a44e3..976a067 100644
--- a/src/covjson_pydantic/observed_property.py
+++ b/src/covjson_pydantic/observed_property.py
@@ -1,17 +1,17 @@
 from typing import List
 from typing import Optional
 
-from .base_models import BaseModel
+from .base_models import CovJsonBaseModel
 from .i18n import i18n
 
 
-class Category(BaseModel):
+class Category(CovJsonBaseModel):
     id: str
     label: i18n
     description: Optional[i18n] = None
 
 
-class ObservedProperty(BaseModel):
+class ObservedProperty(CovJsonBaseModel):
     id: Optional[str] = None
     label: i18n
     description: Optional[i18n] = None
diff --git a/src/covjson_pydantic/parameter.py b/src/covjson_pydantic/parameter.py
index 25b5645..9f684cc 100644
--- a/src/covjson_pydantic/parameter.py
+++ b/src/covjson_pydantic/parameter.py
@@ -6,13 +6,13 @@
 
 from pydantic import model_validator
 
-from .base_models import BaseModel
+from .base_models import CovJsonBaseModel
 from .i18n import i18n
 from .observed_property import ObservedProperty
 from .unit import Unit
 
 
-class Parameter(BaseModel, extra="allow"):
+class Parameter(CovJsonBaseModel, extra="allow"):
     type: Literal["Parameter"] = "Parameter"
     id: Optional[str] = None
     label: Optional[i18n] = None
@@ -32,7 +32,7 @@ def must_not_have_unit_if_observed_property_has_categories(self):
         return self
 
 
-class ParameterGroup(BaseModel, extra="allow"):
+class ParameterGroup(CovJsonBaseModel, extra="allow"):
     type: Literal["ParameterGroup"] = "ParameterGroup"
     id: Optional[str] = None
     label: Optional[i18n] = None
diff --git a/src/covjson_pydantic/reference_system.py b/src/covjson_pydantic/reference_system.py
index 570610a..7222330 100644
--- a/src/covjson_pydantic/reference_system.py
+++ b/src/covjson_pydantic/reference_system.py
@@ -7,17 +7,17 @@
 from pydantic import AnyUrl
 from pydantic import model_validator
 
-from .base_models import BaseModel
+from .base_models import CovJsonBaseModel
 from .i18n import i18n
 
 
-class TargetConcept(BaseModel):
+class TargetConcept(CovJsonBaseModel):
     id: Optional[str] = None  # Not in spec, but needed for example in spec for 'Identifier-based Reference Systems'
     label: i18n
     description: Optional[i18n] = None
 
 
-class ReferenceSystem(BaseModel, extra="allow"):
+class ReferenceSystem(CovJsonBaseModel, extra="allow"):
     type: Literal["GeographicCRS", "ProjectedCRS", "VerticalCRS", "TemporalRS", "IdentifierRS"]
     id: Optional[str] = None
     description: Optional[i18n] = None
@@ -49,6 +49,6 @@ def check_type_specific_fields(self):
         return self
 
 
-class ReferenceSystemConnectionObject(BaseModel):
+class ReferenceSystemConnectionObject(CovJsonBaseModel):
     coordinates: List[str]
     system: ReferenceSystem
diff --git a/src/covjson_pydantic/unit.py b/src/covjson_pydantic/unit.py
index 63ac5a7..f1783dd 100644
--- a/src/covjson_pydantic/unit.py
+++ b/src/covjson_pydantic/unit.py
@@ -3,16 +3,16 @@
 
 from pydantic import model_validator
 
-from .base_models import BaseModel
+from .base_models import CovJsonBaseModel
 from .i18n import i18n
 
 
-class Symbol(BaseModel):
+class Symbol(CovJsonBaseModel):
     value: str
     type: str
 
 
-class Unit(BaseModel):
+class Unit(CovJsonBaseModel):
     id: Optional[str] = None
     label: Optional[i18n] = None
     symbol: Optional[Union[str, Symbol]] = None

From 4e26ed8a87a4c04e04a58595d5e134090c3d02b7 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Thu, 21 Sep 2023 08:52:18 +0200
Subject: [PATCH 12/17] KDP-1761: Minimum pydantic 2.3

---
 pyproject.toml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/pyproject.toml b/pyproject.toml
index 8bb9666..5f94691 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -20,7 +20,7 @@ classifiers = [
     "Typing :: Typed",
 ]
 version = "0.2.0"
-dependencies = ["pydantic>=2,<3"]
+dependencies = ["pydantic>=2.3,<3"]
 
 [project.optional-dependencies]
 test = ["pytest", "pytest-cov"]

From 971c400cb57efe41b346c37a2aeb66e0e0791f02 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 22 Sep 2023 11:33:39 +0200
Subject: [PATCH 13/17] KDP-1761: Also domain can have extra fields

---
 src/covjson_pydantic/domain.py | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index cde31f4..4a41713 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -66,7 +66,7 @@ def at_least_one_axes(self):
         return self
 
 
-class Domain(CovJsonBaseModel):
+class Domain(CovJsonBaseModel, extra="allow"):
     type: Literal["Domain"] = "Domain"
     domainType: Optional[DomainType] = None  # noqa: N815
     axes: Axes

From 8b911ffc9444959d2418569aa2105cd5074737f9 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 22 Sep 2023 11:46:45 +0200
Subject: [PATCH 14/17] KDP-1761: Add note about issue

---
 src/covjson_pydantic/i18n.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/src/covjson_pydantic/i18n.py b/src/covjson_pydantic/i18n.py
index 4959b37..9a345b6 100644
--- a/src/covjson_pydantic/i18n.py
+++ b/src/covjson_pydantic/i18n.py
@@ -14,5 +14,6 @@ class LanguageTag(str, Enum):
 # This may be a bug in Pydantic: https://github.com/pydantic/pydantic/issues/6467
 # or: https://github.com/pydantic/pydantic/issues/6422
 # So, for now, reverted to a less strict type
+# See issue: https://github.com/KNMI/covjson-pydantic/issues/3
 # i18n = Dict[LanguageTag, str]
 i18n = Dict[str, str]

From 84b0a7f9f9db4b62c9b495b34a351b103c7b95e0 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Fri, 22 Sep 2023 13:38:07 +0200
Subject: [PATCH 15/17] KDP-1761: Enable strict mode

---
 src/covjson_pydantic/base_models.py | 1 +
 src/covjson_pydantic/domain.py      | 4 +++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/covjson_pydantic/base_models.py b/src/covjson_pydantic/base_models.py
index b5e68af..4c1c3eb 100644
--- a/src/covjson_pydantic/base_models.py
+++ b/src/covjson_pydantic/base_models.py
@@ -9,4 +9,5 @@ class CovJsonBaseModel(PydanticBaseModel):
         extra="forbid",
         validate_default=True,
         validate_assignment=True,
+        strict=True,
     )
diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index 4a41713..89da847 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -30,7 +30,9 @@ def single_value_case(self):
 ValuesT = TypeVar("ValuesT")
 
 
-class ValuesAxis(CovJsonBaseModel, Generic[ValuesT], extra="allow"):
+# Combination between Generics (ValuesT) and datetime and strict mode causes issues between JSON <-> Pydantic
+# conversions. Strict mode has been disabled. Issue: https://github.com/KNMI/covjson-pydantic/issues/4
+class ValuesAxis(CovJsonBaseModel, Generic[ValuesT], extra="allow", strict=False):
     dataType: Optional[str] = None  # noqa: N815
     coordinates: Optional[List[str]] = None
     values: List[ValuesT]

From 22e7f01863d5ca8f383bb8bd7c617a9913561b66 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Mon, 25 Sep 2023 09:25:27 +0200
Subject: [PATCH 16/17] KDP-1761: Fix example

---
 README.md  | 4 ++--
 example.py | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/README.md b/README.md
index e21b373..ae39aca 100644
--- a/README.md
+++ b/README.md
@@ -38,12 +38,12 @@ pip install git+https://github.com/KNMI/covjson-pydantic.git
 from datetime import datetime, timezone
 from pydantic import AwareDatetime
 from covjson_pydantic.coverage import Coverage
-from covjson_pydantic.domain import Domain, Axes, ValuesAxis
+from covjson_pydantic.domain import Domain, Axes, ValuesAxis, DomainType
 from covjson_pydantic.ndarray import NdArray
 
 c = Coverage(
     domain=Domain(
-        domainType="PointSeries",
+        domainType=DomainType.point_series,
         axes=Axes(
             x=ValuesAxis[float](values=[1.23]),
             y=ValuesAxis[float](values=[4.56]),
diff --git a/example.py b/example.py
index bb4d902..a494f56 100644
--- a/example.py
+++ b/example.py
@@ -4,13 +4,14 @@
 from covjson_pydantic.coverage import Coverage
 from covjson_pydantic.domain import Axes
 from covjson_pydantic.domain import Domain
+from covjson_pydantic.domain import DomainType
 from covjson_pydantic.domain import ValuesAxis
 from covjson_pydantic.ndarray import NdArray
 from pydantic import AwareDatetime
 
 c = Coverage(
     domain=Domain(
-        domainType="PointSeries",
+        domainType=DomainType.point_series,
         axes=Axes(
             x=ValuesAxis[float](values=[1.23]),
             y=ValuesAxis[float](values=[4.56]),

From 44c7a28e72d50c5a566baf39958cf21739715e92 Mon Sep 17 00:00:00 2001
From: Paul van Schayck <paul.van.schayck@knmi.nl>
Date: Mon, 25 Sep 2023 13:07:09 +0200
Subject: [PATCH 17/17] KDP-1761: Workaround for FastAPI issue

---
 src/covjson_pydantic/domain.py | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/covjson_pydantic/domain.py b/src/covjson_pydantic/domain.py
index 89da847..1b37489 100644
--- a/src/covjson_pydantic/domain.py
+++ b/src/covjson_pydantic/domain.py
@@ -8,6 +8,7 @@
 from typing import Union
 
 from pydantic import AwareDatetime
+from pydantic import field_validator
 from pydantic import model_validator
 from pydantic import PositiveInt
 
@@ -74,6 +75,16 @@ class Domain(CovJsonBaseModel, extra="allow"):
     axes: Axes
     referencing: Optional[List[ReferenceSystemConnectionObject]] = None
 
+    # TODO: This is a workaround to allow domainType to work in strict mode, in combination with FastAPI.
+    # See: https://github.com/tiangolo/fastapi/discussions/9868
+    # And: https://github.com/KNMI/covjson-pydantic/issues/5
+    @field_validator("domainType", mode="before")
+    @classmethod
+    def value_to_enum(cls, v):
+        if isinstance(v, str):
+            return DomainType(v)
+        return v
+
     @staticmethod
     def check_axis(domain_type, axes, required_axes, allowed_axes, single_value_axes):
         # Check required axes