fhir_models Build Status

FHIR R4 Resource models generated from FHIR StructureDefinitions.

The StructureDefinitions, XML Schemas, and examples are reused from the HL7 FHIR build tools.

Getting Started

$ bundle install
$ bundle exec rake fhir:console


  • FHIR R4 Resource Models
  • XML and JSON support
  • Resource Validation
  • Not Supported
    • Primitive Extensions
    • FHIR Comments

Resource Basics

Using XML...

  xml = File.read('patient-example.xml')
  patient = FHIR.from_contents(xml)
  puts patient.to_xml

Using JSON...

  json = File.read('patient-example.json')
  patient = FHIR.from_contents(json)
  puts patient.to_json

Creating an Observation by hand...

  obs = FHIR::Observation.new(
    'status' => 'final',
    'code' => {
      'coding' => [{ 'system' => 'http://loinc.org', 'code' => '3141-9', 'display' => 'Weight Measured' }],
      'text' => 'Weight Measured'
    'category' => {
      'coding' => [{ 'system' => 'http://hl7.org/fhir/observation-category', 'code' => 'vital-signs' }]
    'subject' => { 'reference' => 'Patient/example' },
    'context' => { 'reference' => 'Encounter/example' }
  obs.valueQuantity = FHIR::Quantity.new(
    'value' => 185,
    'unit' => 'lbs',
    'code' => '[lb_av]',
    'system' => 'http://unitsofmeasure.org'

### Validation

Using built in validation...

  patient.valid? # returns true or false
  patient.validate # returns Hash of errors, empty if valid

Using a profile or structure definition...

  sd = FHIR::Definitions.resource_definition('Patient')
  sd.validates_resource?(patient) # passing in FHIR::Patient
  # Validation failed? Get the errors and warnings...
  puts sd.errors
  puts sd.warnings


Copyright 2014-2019 The MITRE Corporation

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at


Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.