FHIR Resource List for Sync

FHIR DSTU3 will be the primary method of data transfer between the Child and Parent nodes in a Sync network. Wherever possible we should default to using FHIR representations and rely on other methods only if OpenMRS objects cannot be represented using FHIR resources. Atom feeds used by Sync should point to FHIR urls for resources that are transmitted using FHIR.

The OpenMRS FHIR module will be extended to server both as a client and server that will be leveraged by Sync to create and read FHIR representations that will be used in pushing or pulling data. The FHIR services from the module will also be used by Sync to persist FHIR representations it retrieves from the Parent. Overall the module will be used in 3 ways in Sync:

1) On a Parent - as the server that receives data pushed from it's Children

2) As a client - on Children to both retrieve data from events published on their Parent, but also in their own atom feed. It will also be used to push data to their Parent.

3) As services to persist FHIR representations - on Children that retrieve FHIR resources from a Parent and need to persist them in OpenMRS.

Resource List

This is a list of domain objects that implement BaseOpenmrsData that we want to synchronize between OpenMRS servers. While we want to use FHIR as much as we can, it might come up that for some objects we will have to implement a different Sync protocol.

No	OpenMRS Entity	FHIR Resource	FHIR Maturity Level	Notes
1	Patient	https://www.hl7.org/fhir/patient.html	5
2	Obs	https://www.hl7.org/fhir/observation.html	5
3	Encounter	https://www.hl7.org/fhir/encounter.html	2
4	Visit	List of encounters can be considered: https://www.hl7.org/fhir/list.html		FHIR's Encounter resource can serve either as an OpenMRS Encounter or OpenMRS Visit. OpenMRS Encounter is a point in time. If a FHIR Encounter spans a period of time (e.g., days), it would be an OpenMRS Visit. If a FHIR Encounter has observations linked to it, it's an OpenMRS Encounter
5	Provider	https://www.hl7.org/fhir/practitioner.html	3
6	Allergy	https://www.hl7.org/fhir/allergyintolerance.html	3
7	Drug	https://www.hl7.org/fhir/medication.html	3
8	Location	https://www.hl7.org/fhir/location.html	3
9	Order	https://www.hl7.org/fhir/medicationrequest.html		FHIR Nutrition Order and MedicationRequest can be considered, but orders have a broader sense in OpenMRS. Priority would be MedicationRequest (Drug Order) and ProcedureRequest (Test Order)
10	PatientProgram	https://www.hl7.org/fhir/episodeofcare.html	2
11	PatientState	https://www.hl7.org/fhir/condition.html	3
12	Person	https://www.hl7.org/fhir/person.html	2
13	Relationship	https://www.hl7.org/fhir/relatedperson.html	2
14	Cohort	https://www.hl7.org/fhir/group.html	1

Synchronizing objects via FHIR

To add another object to FHIR synchronization, you must implement the FHIR Strategy Pattern

To do this, Firstly you need to create GenericObjectnameStrategy interface if you wish to synchronize Objectname object

It should look more/less like this:

package org.openmrs.module.fhir.api.strategies.objectname;

import org.hl7.fhir.dstu3.model.Objectname;

public interface GenericObjectnameStrategy {

   Objectname getObjectname(String uuid);

   void deleteObjectname(String uuid);

   Objectname updateObjectname(String uuid, Objectname objectname);

   Objectname createObjectname(Objectname objectname);
}

As shown, it should have at least method stubs for getting, deleting, updatng and creating of Objectname object

After that, the interface needs to be implemented by ObjectnameStrategy class that would contain concrete implementatons of method stubs.

A Strategy Util class, like ObjectNameStrategyUtil should be created next to retrieve the implemented strategy in the following way

package org.openmrs.module.fhir.api.strategies.objectname;

import org.openmrs.api.context.Context;
import org.openmrs.module.fhir.api.util.FHIRUtils;

public class ObjectNameStrategyUtil {

   public static GenericObjectNameStrategy getObjectNameStrategy() {
      String strategy = FHIRUtils.getObjectNameStrategy();

      return strategy == null ? new ObjectNameStrategy() :
            Context.getRegisteredComponent(strategy, GenericObjectNameStrategy.class);
   }
}

Strategy Util class will be called in ObjectNameServiceImpl class

package org.openmrs.module.fhir.api.impl;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.hl7.fhir.dstu3.model.ObjectName;
import org.openmrs.api.impl.BaseOpenmrsService;
import org.openmrs.module.fhir.api.ObjectNameService;
import org.openmrs.module.fhir.api.db.FHIRDAO;
import org.openmrs.module.fhir.api.strategies.objectname.ObjectNameStrategyUtil;

public class ObjectNameServiceImpl extends BaseOpenmrsService implements ObjectNameService {

   protected final Log log = LogFactory.getLog(this.getClass());

   private FHIRDAO dao;

   /**
    * @return the dao
    */
   public FHIRDAO getDao() {
      return dao;
   }

   /**
    * @param dao the dao to set
    */
   public void setDao(FHIRDAO dao) {
      this.dao = dao;
   }

   @Override
   public ObjectName getObjectName(String uuid) {
      return ObjectNameStrageryUtil.getObjectNameStrategy().getObjectName(uuid);
   }

   @Override
   public void deleteObjectName(String uuid) {
      ObjectNameStrageryUtil.getObjectNameStrategy().deleteObjectName(uuid);
   }

   @Override
   public ObjectName updateObjectName(String uuid, ObjectName objectName) {
      return ObjectNameStrategyUtil.getObjectName().updateObjectName(uuid, objectName);
   }

   @Override
   public ObjectName createObjectName(ObjectName objectName) {
      return ObjectNameStrategyUtil.getObjectNameStrategy().createObjectName(ObjectName);
   }
}

Which should implement an ObjectNameService interface

package org.openmrs.module.fhir.api;

import org.hl7.fhir.dstu3.model.ObjectName;
import org.openmrs.api.OpenmrsService;
import org.springframework.transaction.annotation.Transactional;

@Transactional
public interface ObjectNameService extends OpenmrsService {

   /**
    * Get object by id
    *
    * @param uuid The uuid of object
    * @return ObjectName fhir resource
    */
   ObjectName getObjectName(String uuid);

   /**
    * Delete object by id
    *
    * @param uuid The uuid of object
    */
   void deleteObjectName(String uuid);

   /**
    * Update object
    *
    * @param uuid          The uuid of object
    * @param objectName representation of object fhir resource
    */
   ObjectName updateObjectName(String uuid, ObjectName objectName);

   /**
    * Create object
    *
    * @param objectName the object to create
    */
   ObjectName createObjectName(ObjectName objectName);
}