API Reference

This section provides a detailed API reference for the core types and functions exported by the gofhir/models packages. The same API surface is available in each version package (r4, r4b, r5), with type definitions reflecting the corresponding FHIR specification.

Topics

Resource Interfaces

The Resource and DomainResource interfaces that all FHIR resources implement.

Registry Functions

Factory, deserialization, and introspection functions for dynamic resource handling.

Builder API

Fluent builder pattern with Set/Add methods for every resource type.

FHIRPath Model API

Complete reference for the FHIRPathModelData accessor methods.

API Summary

The library exports a small, focused API surface on top of the generated resource structs:

Category	Key Exports	Purpose
Interfaces	`Resource`, `DomainResource`	Generic resource handling without type assertions
Registry	`NewResource`, `UnmarshalResource`, `GetResourceType`, `IsKnownResourceType`, `AllResourceTypes`	Dynamic resource creation and deserialization
Builders	`New<Resource>Builder`, `Set`, `Add`, `Build`	Fluent resource construction
Serialization	`Marshal`, `MarshalIndent`, `MarshalResourceXML`, `MarshalResourceXMLIndent`, `UnmarshalResourceXML`	FHIR-conformant JSON and XML encoding
Metadata	`FHIRPathModel`, `SummaryFields`	Runtime type information and summary field lists

All examples in this section use the r4 package. The same patterns apply to r4b and r5 with their respective type definitions.

Last updated on September 6, 2026