Validation¶

FHIR validation involves checking FHIR resources against defined profiles, extensions, and structure definitions to ensure that the data is accurate, consistent, and compliant with the expected formats and standards. It is a crucial process in ensuring that healthcare data adheres to the FHIR standard's rules and constraints. FHIR validation helps to identify errors, enforce data integrity, and maintain interoperability across different healthcare systems.

Note

WSO2 Healthcare Solution offers two distinct solutions (Ballerina and Micro Integrator) each tailored to different architectural preferences. For systems that favor the Enterprise Service Bus (ESB) pattern, the Micro Integrator, enhanced with FHIR accelerators, can be utilized.
On the other hand, Ballerina, a programming language specifically designed for integrations, is ideal for implementing FHIR integrations structured as microservices.

BallerinaMicro Integrator

Validating a FHIR resource(s) in Ballerina is supported with the FHIR package. Following example demonstrates how to validate a FHIR Patient resource using Ballerina.

Step 1: Set Up Ballerina¶

Before you begin, ensure you have Ballerina installed on your system. Follow the instructions in the Installation Steps to install Ballerina and set up the development environment.

Step 2: Implement the flow to populate a FHIR resource¶

Create a new Ballerina project using the following command. It will create the Ballerina project and the main.bal file can be used to implement the logic.
```
$ bal new fhir_validation_sample
```

Import the required modules to the Ballerina program.

import ballerina/io;
import ballerinax/health.fhir.r4;
import ballerinax/health.fhir.r4.validator;

Implement the logic to validate the FHIR resources. In this sample, we are validating a sample FHIR json to FHIR Patient resource. We are using the validate() function to validate the FHIR resource. This sample demonstrates how to validate a FHIR Patient resource with an invalid birth date.

import ballerina/io;
import ballerinax/health.fhir.r4;
import ballerinax/health.fhir.r4.validator;

public function main() returns error? {

    json body = {
    "resourceType": "Patient",
    "id": "591841",
    "meta": {
        "versionId": "1",
        "lastUpdated": "2020-01-22T05:30:13.137+00:00",
        "source": "#KO38Q3spgrJoP5fa"
    },
    "identifier": [ {
        "type": {
        "coding": [ {
            "system": "http://hl7.org/fhir/v2/0203",
            "code": "MR"
        } ]
        },
        "value": "18e5fd39-7444-4b30-91d4-57226deb2c78"
    } ],
    "name": [ {
        "family": "Cushing",
        "given": [ "Caleb" ]
    } ],
    "birthDate": "jdlksjldjl"
    };

    r4:FHIRValidationError? validateFHIRResourceJson = validator:validate(body);

    if validateFHIRResourceJson is r4:FHIRValidationError {
        io:print(validateFHIRResourceJson);
    }
}

Step 3: Run the Ballerina Program¶

Run the Ballerina program using the following command:

```bash
$ bal run
```

Validating a FHIR resource(s) in WSO2 Micro Integrator is supported with the FHIR Base connector. Following example demonstrates how to validate a FHIR Patient resource using WSO2 Micro Integrator.

Step 1: Set Up WSO2 Micro Integrator¶

Before you begin, download the WSO2 Micro Integrator and install by following the Installation Steps.

Step 2: Implement the flow to validate a FHIR resource¶

Create a MI project using the MI VSCode plugin by following the guide on Creating a New Integration Project.
Create a REST API to receive a FHIR patient payload.
Add fhirbase connector to the project.

Implement the logic to validate the FHIR resource. The validate operation can be used to validate a FHIR resource from a JSON payload. This operation will trigger fault sequence if the validation fails with the error message details. You can use the properties mentioned here to evaluate the validation result.

Completed flow

<?xml version="1.0" encoding="UTF-8"?>
<api context="/r4" name="PatientAPI" xmlns="http://ws.apache.org/ns/synapse">
    <resource methods="POST" uri-template="/Patient">
        <inSequence>
            <log level="full"/>
            <fhirbase.validate />
        </inSequence>
        <faultSequence>
        </faultSequence>
    </resource>
</api>

Step 3: Deploy and Test the Integration Project¶

Deploy the integration project to the MI runtime by following the guide on Deploying the Integration Project and test the API using a REST client.

Use the following payload to test the API:

{
    "resourceType": "Patient",
    "id": "591841",
    "meta": {
        "versionId": "1",
        "lastUpdated": "2020-01-22T05:30:13.137+00:00",
        "source": "#KO38Q3spgrJoP5fa"
    },
    "identifier": [ {
        "type": {
        "coding": [ {
            "system": "http://hl7.org/fhir/v2/0203",
            "code": "MR"
        } ]
        },
        "value": "18e5fd39-7444-4b30-91d4-57226deb2c78"
    } ],
    "name": [ {
        "family": "Cushing",
        "given": [ "Caleb" ]
    } ],
    "birthDate": "jdlksjldjl"
}