Kinvey's native API format is JSON over HTTP. Many healthcare APIs, use the FHIR standard for transmitting health-related data. This project is a reference Flex Connector for connecting to FHIR-based APIs.
To use this connector, clone this GitHub repository, and install the associated dependencies:
npm install
The DLC can either be deployed to the FlexService Runtime, or run locally. To run locally, you must have node.js v6.x or greater. Execute:
node .
This Flex Connector uses the following dependencies, in addition to the kinvey-flex-sdk:
- async: The async.js module is used managing concurrency in transforming data
- soap: A library for consuming SOAP APIs
- fhir-json-client: Used for connecting to FHIR APIs and returning the results as JSON
This reference connector contains sample automated tests, both unit and integration. To run the tests, execute:
npm test
The Flex Connector implements three methods associated with the Kinvey FlexData API:
- onGetAll
- onGetById
- onGetCount
The service objects and handlers are defined in the index.js file. The handlers are loaded seperately from lib/handlers. This separation is done for two purposes:
a) to increase modularity and reusability of code
b) to facilitate unit testing
// Initiate the Flex SDK Service
sdk.service((err, flex) => {
if (err) {
console.log('Error initializing the Flex SDK, exiting.');
throw err;
}
const data = flex.data; // gets the FlexData object from the service
// Define Service Objects
const patient = data.serviceObject('Patient');
const medication = data.serviceObject('Medication');
const appointment = data.serviceObject('Appointment');
// wire up the events that we want to process
patient.onGetById(handlers.getPatientById);
patient.onGetByQuery(handlers.getPatientByQuery);
patient.onInsert(handlers.createEntity);
patient.onUpdate(handlers.updateEntity);
medication.onGetById(handlers.getMedicationById);
medication.onGetByQuery(handlers.getMedicationByQuery);
medication.onInsert(handlers.createEntity);
medication.onUpdate(handlers.updateEntity);
appointment.onGetById(handlers.getAppointmentById);
appointment.onGetByQuery(handlers.getAppointmentByQuery);
appointment.onInsert(handlers.createEntity);
appointment.onUpdate(handlers.updateEntity);
});
The handlers then perform two steps for every request:
- Make a request to
lib/fhir-clientfor processing the FHIR call and converting the response to JSON - Remove the context root and transform the result into valid Kinvey entities
transformers.js
For example, for onGetById, the handler makes a call to the fhir-client:
fhir.read(resource, id, (err, result) => {
The FHIR Client calls the API, gets the result, and converts the result to JSON:
function _parseResponse(err, response, item, callback) {
if (err != null) {
return callback(err);
} else if (response != null && response.statusCode > 299) {
return callback(response)
} else {
return callback(err, item);
}
}
exports.read = function read(resource, item, callback) {
client.read(resource, item, (err, response, item) => {
_parseResponse(err, response, item, callback);
});
};
Finally, the transformer is called to return the result:
function transformEntity(entity, modules) {
if (typeof entity !== 'object') {
return new Error('The entity must be an object.');
}
if (Array.isArray(entity)) {
return new Error('Arrays are not permitted. Only a single entity may be supplied.');
}
if (entity.id == null) {
return new Error('No id field (_id) present in the resulting entity');
}
if (modules == null || modules.kinveyEntity == null || modules.kinveyEntity.entity == null) {
return new Error('A valid modules object must be supplied');
}
const mappedEntity = modules.kinveyEntity.entity(entity);
mappedEntity._id = entity.id;
return mappedEntity;
}
After transforming, we complete the flex request and return the results to the request pipeline for further processing:
return complete().setBody(result).ok().next();
React
Typescript
Django
Laravel
Facebook
Microsoft
Google
Alibaba
D3
Tencent