Installation

Just a simple pip install fhir-core. But if you want development version, just clone from https://github.com/nazrulworld/fhir-core and pip install -e .[dev].

Usages

Example: 1: This example creates an Organization class with some of its attributes (id, active, name, address):

>>> from typing import List
>>> from pydantic import Field
>>> from fhir_core.fhirabstractmodel import FHIRAbstractModel
>>> from fhir_core.types import IdType, BooleanType, StringType
>>> data = {
...     "id": "f001",
...     "active": True,
...     "name": "Acme Corporation",
...     "address": ["Road 10": "Acme corporation", "2390", "USA"}]
... }
>>> class Organization(FHIRAbstractModel):
...     __resource_type__ = "Organization"
...     id: IdType = Field(None, title="Id", alias="id", json_schema_extra={"element_property": True})
...     active: BooleanType = Field(None, title="Active", alias="active", json_schema_extra={"element_property": True})
...     name: StringType = Field(None, title="Name", alias="name", json_schema_extra={"element_property": True})
...     address: ListType[StringType] = Field(None, title="Address lines", alias="address", json_schema_extra={"element_property": True})
...
...     @classmethod
        def elements_sequence(cls):
            return ["id", "active", "name", "address"]
...
>>> org = Organization.model_validate(data)
>>> org.active is True
True
>>> org_json_str = org.model_dump_json()
>>> Organization.model_validate_json(org_json_str).model_dump() == org.model_dump()
True

Complex examples

1. https://github.com/nazrulworld/fhir-core/blob/main/tests/fixtures/resources/extension.py

2. https://github.com/nazrulworld/fhir-core/blob/main/tests/fixtures/resources/fhirtypes.py

3. https://github.com/nazrulworld/fhir-core/blob/main/tests/fixtures/resources/codesystem.py

© Copyright HL7® logo, FHIR® logo and the flaming fire are registered trademarks owned by Health Level Seven International

1.1.12 (2026-10-18)

New feature

• Global model_config customization for FHIR models #21 [developer-rpai]

• Make Id constraints customizable again: max_length and pattern are now resolved from fhir_core.constraints.TYPES_ID_MAX_LENGTH / TYPES_ID_PATTERN at schema build time, so patching those values before the FHIR models are imported relaxes validation as documented nazrulworld/fhir.resources#173

Fixes

• Accept leap seconds (23:59:60) in the dateTime, instant and time types as the FHIR specification allows. Python’s datetime cannot represent a second of 60, so such a value is validated and kept as the original string nazrulworld/fhir.resources#212

• Annotate **pydantic_kwargs as typing.Any on the serializer methods (model_dump, model_dump_json, model_dump_yaml, model_dump_xml, dict, json), so strict type checkers no longer see them as Unknown.

• Omit empty lists from model_dump(), model_dump_json() and model_dump_yaml() output, like None values, as FHIR elements are never empty (the XML serializer already left them out). They are kept when exclude_none=False is passed nazrulworld/fhir.resources#74

1.1.11 (2026-09-13)

• Reject None elements in lists of complex types; primitive lists keep their null placeholders nazrulworld/fhir.resources#208 [asaraog]

• Serialize the FHIR uuid type as the URI the specification asks for, urn:uuid:<uuid>, instead of a bare UUID nazrulworld/fhir.resources#180

• Restore the lower bounds on unsignedInt and positiveInt so negative values no longer validate nazrulworld/fhir.resources#207 [asaraog]

• Resolve the FHIR version prefix through the class MRO so model_dump_xml() works on subclasses nazrulworld/fhir.resources#209 [asaraog]

• Fix KeyError during model_dump() when a subclass overrides a field’s default and drops its alias nazrulworld/fhir.resources#182 [asaraog]

1.1.10 (2026-07-25)

• Fix issue #23 with annotated_types package after 0.8.0

1.1.9 (2026-06-28)

• Fix regression where input to Decimal type can lose exponent i.e. 1.0 remains 1.0 not 1 #20

• For primitive type’s value required validation, empty extension is now acceptable.

1.1.8 (2026-04-30)

• Fixes: Decimal values lose precision during serialization — Decimal(‘19’) becomes 19.0 in both model_dump() and model_dump_json() fhir.resources#203 [cmodevcodes]

1.1.7 (2026-03-22)

• Fixes error in supporting multiple fhir version into xml utilities.

1.1.6 (2026-03-19)

• Fix FHIR_TYPES_MAPS global state prevents using multiple FHIR versions in same process https://github.com/nazrulworld/fhir.resources/issues/202

1.1.5 (2026-01-29)

• Fixes the issue #16 “Encounter.class missing when serializing to XML”.

• Fixes the issue #14 “Wrong serialization of Instant type” [dhallam].

1.1.4 (2025-07-11)

• Fixes the issue #13 “pyright struggles with default position args”.

1.1.3 (2025-07-10)

• Fixes business logic for xml serializer, when summary move is active.

1.1.2 (2025-07-09)

• Fixes nested ignoring (non primitive field serialization), if summary mode is enabled.

• Issue #12 missing xmlparser argument for FHIRAbstractModel.model_validate_xml.

1.1.1 (2025-07-04)

• Extra field property name is_summery_element has been renamed to summary_element_property

1.1.0 (2025-07-01)

New features

• Issue 11: <https://github.com/nazrulworld/fhir-core/issues/11>_ Added support for FHIR _summary based filter during serialization.

1.0.2 (2025-06-23)

Fixes

• Issue: deprecated access of model_fields in Pydantic model instances. https://github.com/nazrulworld/fhir-core/issues/9.

1.0.1 (2025-03-23)

Fixes

• External issue https://github.com/nazrulworld/fhir.resources/issues/175

1.0.0 (2024-12-25)

• XML serialization/deserialization support has been added.

• Remove dependency on typed-ast as it is not needed and won’t work in later Python versions.

• Fix typo in test case.

• Raising ‘ValueError’ has been suspended inside Fhir Model Validation ‘fhir_model_validator()’, if None value is provided.

0.1.3 (2024-10-24)

• Improves missing value validation message, as error type is now model_field_validation.missing.

0.1.2 (2024-10-09)

• Improve validation error message.

0.1.1 (2024-10-09)

• Version policy updated, now .bx suffix has been removed.

Fixes

• Business logic for None type validation against FHIR Model validator as None value is acceptable! Instead, you should make Pydantic field optional.

0.1.0b9 (2024-10-02)

Fixes

• Issue: AttributeError: ‘NoneType’ object has no attribute ‘__resource_type__’ https://github.com/nazrulworld/fhir.resources/issues/164#issuecomment-2338404044

0.1.0b8 (2024-08-04)

• YAML dump & validate options are added into FHIRAbstractModel.

0.1.0b7 (2024-07-31)

• typing hint added for the function ´´create_fhir_type´´ and ´´create_fhir_element_or_resource_type´´.

0.1.0b6 (2024-07-30)

• Core configurations for types Id & String are coming from constraint module.

• Default maximum char length Id is now 255.

0.1.0b5 (2024-07-28)

• Fixes the function that is checking is_primitive, as missing bytes and bytesarray are added.

• Encoding is handled for Base64Binary type.

0.1.0b4 (2024-07-28)

• Fixes extension serialization.

0.1.0b3 (2024-07-28)

• Fixes the function that is checking is_primitive.

• Fixes validator for Resource & Element types.

0.1.0b2 (2024-07-27)

Bugfixes

• Fixes pattern as string for some of primitives types. fx UriType.

• Fixes model serializer.

0.1.0b1 (2024-07-26)

• The first beta release! and this release is not stable enough to use in production.