@i4mi/fhir_r4 v2.1.4

I4MI on FHIR® - fhir-resources-r4.ts

FHIR® resources, inheritance and type definitions.
Generated from the FHIR® definition json by the Institute of Medical Informatics (I4MI).

Usage guide

Install with

npm i @i4mi/fhir_r4

Select fhir version

This library supports the following fhir versions:

• R4 (v4.0.1)

Use with NodeJS

If you want to use this library in a node project which does not run on any browser, you need to install further dependencies.

1. Install XMLHttpRequest:

npm i xmlhttprequest

2. Set global var

global['XMLHttpRequest'] = require("xmlhttprequest").XMLHttpRequest;

or

const XMLHttpRequestLib = require("xmlhttprequest").XMLHttpRequest;
global['XMLHttpRequest'] = XMLHttpRequestLib;

3. You're up to go

Using resources

How do I select the resource from a specific Version? Just import resources from the path:

import { Patient, Bundle, Practitioner, Observation, Consent, Group } from '@i4mi/fhir_r4';

Then you can use them as types or implement them.

Use as Type:

let patient: Patient = {
    resourceType: 'Patient'
    ...
}

Implement

export class MyPatient implements Patient {
    resourceType = 'Patient';

    ...
}

NOTE: You always have to set the resourceType!

Create api calls

How do I create api calls?
Import statement for using all implemented api methods

import { ApiMethods, apiCall, ApiCallResponse } from '@i4mi/fhir_r4';

Then create a method, which returns the initialized ApiMethods class. We recomment doing this in a service. You need a valid access token, the token type and the url to the fhir server. For example:

• ACCESS_TOKEN = 'eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJzdWIiOiIxMjM0NTY3ODkwIiwibmFtZSI6IkpvaG4gRG9lIiwiYWRtaW4iOnRydWUsImp0aSI6IjRlMjI4YTllLWZmMTMtNDgzNy1iOWFkLTI3NzcxYjM1YWIzNyIsImlhdCI6MTU2NTM1ODc0OCwiZXhwIjoxNTY1MzYyMzQ5fQ.CAfKTeRuGWQxzFuJM7hrB2z4sHuYplP1uXm_B_zkfjM'
• TOKEN_TYPE = 'Bearer'
• FHIR_SERVER_URL = https://your-url.coop

Then create the function. It should look something like this:

/**
 * Inits the api method class
 */
private getAPI(): ApiMethods {
  return new ApiMethods({
    access_token: ACCESS_TOKEN,
    authorization_type: TOKEN_TYPE,
    base_url: FHIR_SERVER_URL + '/fhir'});
}

IMPORTANT: When the token has changed, you have to re-init the ApiMethods class.

In the now created service, implement a function which assigns the ApiMethods instance to a member.

/**
 * Execute init of API mehtods
 */
initApiMethods() {
  this.apiMethods = this.getAPI();
}

The now assigned instance this.apiMethods can be used to execute create, update, read and search. These methods are implemented according the smart on fhir implementation guidelines.

IMPORTANT: Check the allowed content type (header) of your target server. If it is different than the default "application/fhir+json;fhirVersion=4.0", call differentiateContentType([YOUR_TYPE]) BEFORE sending any request. For example:

this.apiMethods.differentiateContentType("application/fhir+json;charset=utf-8");

Other examples (search, create, etc.)

Search:

myStaticPatientSearch() {
    this.apiMethods.search({ _id: 1 }, 'Patient')
        .then((response) => {
            console.log(response);
        });
}

Create:

myStaticPatientCreate() {
    const myPatient: Patient = {
        resourceType: 'Patient',
        name: {
            given: [
                'Hans'
            ],
            family: 'Muster'
        }
    }

    this.apiMethods.create(myPatient, 'Patient').then(
        (response) => {
            console.log(response);
        });
}

Smart resources and utils

This library also provides some smart resources and utils to make your life with FHIR® easier.

I4MIBundle

This smart resource represents a Bundle, and lets you add and remove entries. First, the Bundle has to be initialized by calling const myBundle = new I4MIBundle(type), where type is the BundleType needed.

After initializing the Bundle, you can add an entry by calling myBundle.addEntry(verb, entry), where verb is the BundleHTTPVerb for the entry, and entry the resource you want to add to the Bundle. Contrary to earlier versions of the library, it is not necessary anymore to explicitly specify the resourceType.

For removing an entry from the resource, you can call myBundle.removeEntry(id), where id is the id of the resource in the entry.

Internationalization (I18N)

FHIR® supports I18N with extensions. Any text / string element can have an extensible sibling with an leading underscore, that contains the internationalization strings (e.g. if a resource has a resource.title element, the corresponding extensible element would be resource._title).

With readI18N() and writeI18N(), this library provides two functions that help with interacting with this translation extensions.

readI18N(resource._title, 'en') allows you to read the translation string for a given element and language (in this case, the resource title in english.) If the element does not have a well formed I18N extension or the respective language is not available, undefined is returned (and you have to fall back on the normal resource.title element or another a language).

writeI18N(translations) allows you to comfortably write wellformed I18N extensions to a resource element. The 'translations' argument is a key/value pair of the languages and I18N string you want to write, as in the following example:

const translations = {
    en: 'This is the title.',
    fr: 'Voici le titre.',
    de: 'Dies ist der Titel.'
};
resource._title = writeI18N(translations);

Contribution & dev guide

build

to generate a new build in './dist/'

npm run build

deploy

update version in package.json then

npm publish --access public

FHIR® is the registered trademark of HL7 and is used with the permission of HL7. Use of the FHIR® trademark does not constitute endorsement of this product by HL7.