Epic FHIR Adapter

Refer to Set up your Epic FHIR Sandbox for the sign up process, creating and client and gathering the authentication details needed for the Epic FHIR Adapter.

See Create a Component if this is your first time!

Enter the ClientId and PrivateKey certificate path.

Using the information provided, the component will run through the authentication workflow and set the Key and KeyExpiry value of the obtained access token automatically.

The FHIRresources.lua file included in the project contains the schema for a FHIR R4 Patient and Appointment resource. This file can be replaced with the schemas you require.

See FHIR Profiling Tool for how to generate the FHIRresources.lua file containing the FHIR resource schemas you need to create.

Using the FHIR Library, FHIRCreate generates an empty FHIR Resource for you to map.

local NewPatient = FHIRcreate{resource='Patient'}
-- then populate your FHIR resource with data

Set live=true to invoke each interaction.

-- Create the new patient
E:create{resource="Patient",parameters=NewPatient,live=true}
   
-- Search for our patient
local Search = {
   family = 'Lufhir',  
   given = 'Sakiko',
   birthdate = '1994-07-22'
   }
local Status, R = E:search{resource="Patient",parameters=Search,live=true}     

View the resultant patient search in the Annotations:

Sets up the EPIC FHIR adapter framework, adding the various method modules to a metatable and storing the configurations added to the custom fields.

The EPICFHIRauth function, builds and makes the HTTP POST token request to obtain the access token required for any resource requests against the FHIR Server.

A separate CreateJWT function creates the JSON Header and Payload components of the JWT and calls the OAUTH Library to sign and return the JWT required for the token request.

If the token requests is successful (HTTP 200 response), the token and token expiry returned are set to the Key and KeyExpiry custom fields respectively.

EPICcustom takes in any API requests and parameters to make the API call and return the response.

• First the function checks if the token Key exists and performs the OAuth2.0 authentication workflow to obtain the token to be used in subsequent requests.

• Uses the passed configurations API request parameters - the method (ex. post), API (ex. Patient) and parameters for the call (ex. the patient resource to be created) - to build and carry out the appropriate HTTP request.

• For resiliency, the Retry Library is used to retry any failed attempts and the response is handled and returned.

EPICFHIRcreate prepares the arguments and calls EPICFHIRcustom for an FHIR Resource Create HTTP POST request.

EPICFHIRsearch prepares the arguments and calls EPICFHIRcustom for an FHIR Resource Search HTTP GET request.

EPICFHIRreadResource prepares the API endpoint and arguments to call EPICFHIRcustom for an FHIR Resource Read HTTP GET request.

EPICFHIRoperation prepares the arguments and calls EPICFHIRcustom for an FHIR Resource Create HTTP GET or POST request.

A FHIR operation is extended functionality unique across FHIR Servers. Extended operations on a resource use a $ in front of the operation. For example, when calling EPICFHIRcustom, the passed api argument may be “Patient/$match“ to perform a more detailed patient matching search.