FHIR resource handling

# -*- coding: utf-8 -*-

# Zato
from zato.server.service import Service

# #############################################################################
# #############################################################################

class CreatePatient(Service):
    """ Creates a new patient and reads it back from the FHIR server.
    """
    name = 'fhir-api.create-patient'

    def handle(self) -> 'None':

        # The connection's name is all it takes to obtain a client ..
        client = self.fhir['FHIR.Sample']

        # .. a resource behaves like an object and a dict alike ..
        patient_name = [{'family': 'Chalmers', 'given': ['Peter']}]
        patient = client.resource('Patient', name=patient_name)

        patient.birthDate = '1974-12-25'
        patient['gender'] = 'male'

        # .. and one save stores it on the server.
        patient.save()

        self.logger.info(f'Created Patient/{patient.id}')

        # Read it back by type and the ID the server assigned
        found = client.get('Patient', patient.id)

        family_name = found['name'][0]['family']
        self.logger.info(f'Family name is {family_name}')

# -*- coding: utf-8 -*-

# Zato
from zato.server.service import Service

# ##############################################################################
# ##############################################################################

class FindObservations(Service):
    """ Searches a FHIR server for matching observations.
    """
    name = 'fhir-api.find-observations'

    def handle(self) -> 'None':

        client = self.fhir['FHIR.Sample']

        # Everything about observations starts here ..
        observations = client.resources('Observation')

        # .. final observations for one patient, from 2024 on, newest first ..
        result = observations.search(
            subject='Patient/544ccba4010d4458a3cc31d75b828412',
            status='final',
            date__ge='2024-01-01',
        ).sort('-date').limit(10)

        # .. and only now is the server invoked.
        for observation in result.fetch():
            code = observation['code']
            self.logger.info(f'Observation: {code}')

# One page of results, as configured with .limit
found = result.fetch()

# All the results - pagination is followed for you
found_all = result.fetch_all()

# The first match or None
observation = result.first()

# Only the number of matches, without any resources
match_count = observations.search(status='final').count()

# Read the resource first.
patient = client.get('Patient', '544ccba4010d4458a3cc31d75b828412')

# Change a field and store the whole resource ..
patient.birthDate = '1974-12-26'
patient.save()

# .. or send only one field, leaving the rest untouched.
patient.patch(birthDate='1974-12-27')

patient.refresh()
patient.delete()

# Find an observation ..
observation = client.resources('Observation').search(status='final').first()

# .. its subject is a reference, e.g. Patient/544ccba4010d4458a3cc31d75b828412 ..
subject = observation['subject']

# .. and this fetches the actual Patient from the server.
patient = subject.to_resource()

family_name = patient['name'][0]['family']
self.logger.info(f'Patient is {family_name}')

appointment = client.resource('Appointment')

appointment.status      = 'booked'
appointment.participant = [{'actor': patient, 'status': 'accepted'}]
appointment.start       = '2027-01-11T11:11:11.111+00:00'
appointment.end         = '2027-01-11T12:11:11.111+00:00'

appointment.save()

patient = client.get('Patient', '544ccba4010d4458a3cc31d75b828412')

# The first given name of the first name entry
given_name = patient.get_by_path('name.0.given.0')

# The home phone number, wherever it is in the telecom list -
# a dict selects the first list element whose fields match it.
phone = patient.get_by_path(['telecom', {'system': 'phone', 'use': 'home'}, 'value'])

# If anything along the path does not exist, the default is returned.
maiden_name = patient.get_by_path('name.1.family', '(none)')

# Zato
from zato.fhir.path_access import get_path, set_path

data = {'name': [{'family': 'Smith', 'given': ['John']}]}

family = get_path(data, 'name[0].family')
_ = set_path(data, 'name[0].family', 'Jones')

# The whole HL7 v2 message becomes a FHIR transaction bundle
bundle = msg.to_fhir()

# The same conversion as pretty-printed JSON, e.g. for logging
bundle_json = msg.to_fhir_json(indent=2)

# Stored atomically - all the resources or none
client.execute('', method='post', data=bundle.to_dict())

# Zato
from zato.fhir import Patient

patient            = Patient()
patient.identifier = [{'value': msg.pid.patient_identifier_list[0].id_number}]
patient.name       = [{'family': msg.pid.patient_name.family_name}]