Introduction

This series of examples shows how to do many common activities with the drchrono API. For more detailed information, view the documentation. If you are upgrading from a previous version, view the changelog.

Create an account

You need a free drchrono account in order to create and test your application. Sign up!

Create your application

To create your application, go to the API management page (also available under "Account" > "Other Settings" > "API") and click the "New Application" button. Fill in the name of your application and add one or more Redirect URIs, then click the "Save Changes" button on the bottom.

A Redirect URI is a web location starting with http:// or https:// that the user will be redirected to during the log-in flow. Note that this must be an address you control, but it need not present any content to the user, although we do recommend presenting a helpful message such as "Congratulations! You just integrated with :app!".

Client setup

For performing the OAuth workflow, you can use an OAuth 2.0 library. This page lists clients for various popular programming languages. You can find your client id, secret, and redirect URIs for configuring your library on the API management page, and the authorization and token URLs are:

You can also perform the OAuth workflow using any general purpose HTTP client library.

The drchrono API is versioned. When you create an application, it will default to using the latest version. This can be modified at any time on the API application management page. It can also be set for individual requests with the X-DRC-API-Version header.

OAuth

Our API uses OAuth 2.0, a common web-based authorization system. It provides a straightforward way for a provider to grant access your application access to their data.

Authentication workflow

There are three main steps in the OAuth 2.0 authentication workflow:

  1. Redirect the provider to the authorization page.
  2. The provider authorizes your application and is redirected back to your web application.
  3. Your application exchanges the authorization_code that came with the redirect for an access_token and refresh_token.

Step 1: Redirect to drchrono

The first step is redirecting your user to drchrono, typically with a button labeled "Connect to drchrono" or "Login with drchrono". This is just a link that takes your user to the following URL:

https://drchrono.com/o/authorize/?redirect_uri=REDIRECT_URI_ENCODED&response_type=code&client_id=CLIENT_ID_ENCODED&scope=SCOPES_ENCODED

Step 2: Provider authorization

After logging in (if necessary), the provider will be presented with a screen with your application's name and the list of permissions you requested (via the scope parameter).

When they click the "Authorize" button, they will be redirected to your redirect URI with a code query parameter appended, which contains an authorization code to be used in step 3. If they click the "Cancel" button, they will be redirected to your redirect URI with error=access_denied instead.

Note: This authorization code expires extremely quickly, so you must perform step 3 immediately, ideally before rendering the resulting page for the end user.

Step 3: Token exchange

The code obtained from step 2 is usable exactly once to obtain an access token and refresh token. Here is an example token exchange in Python:

import datetime, pytz, requests

if 'error' in get_params:
    raise ValueError('Error authorizing application: %s' % get_params[error])

response = requests.post('https://drchrono.com/o/token/', data={
    'code': get_params['code'],
    'grant_type': 'authorization_code',
    'redirect_uri': 'http://mytestapp.com/redirect_uri',
    'client_id': 'abcdefg12345',
    'client_secret': 'abcdefg12345',
})
response.raise_for_status()
data = response.json()

# Save these in your database associated with the user
access_token = data['access_token']
refresh_token = data['refresh_token']
expires_timestamp = datetime.datetime.now(pytz.utc) + datetime.timedelta(seconds=data['expires_in'])

You now have all you need to make API requests authenticated as that provider. When using this access token, you'll only be able to access the data that the user has access to and that you have been granted permissions for.

Refreshing an access token

Access tokens only last 48 hours (given in seconds in the 'expires_in' key in the token exchange step above), so they occasionally need to be refreshed. It would be inconvenient to ask the user to re-authorize every time, so instead you can use the refresh token like the original authorization to obtain a new access token. Replace the code parameter with refresh_token, change the value grant_type from authorization_code to refresh_token, and omit the redirect_uri parameter.

Example in Python:

...
response = requests.post('https://drchrono.com/o/token/', data={
    'refresh_token': get_refresh_token(),
    'grant_type': 'refresh_token',
    'client_id': 'abcdefg12345',
    'client_secret': 'abcdefg12345',
})
...

Main API Usage

Getting user information

Often, the first request that is made is to /api/users/current to get information about the currently logged in user:

import requests

response = requests.get('https://drchrono.com/api/users/current', headers={
    'Authorization': 'Bearer %s' % access_token,
})
response.raise_for_status()
data = response.json()

# You can store this in your database along with the tokens
username = data['username']

Getting the patient list

The /api/patients endpoint, like all listing endpoints, is paginated. You'll need to iterate over the results to get them all.

import requests

headers = {
    'Authorization': 'Bearer ACCESS_TOKEN',
}

patients = []
patients_url = 'https://drchrono.com/api/patients'
while patients_url:
    data = requests.get(patients_url, headers=headers).json()
    patients.extend(data['results'])
    patients_url = data['next'] # A JSON null on the last page

If you have a patient's name, you can pass the ?first_name= or ?last_name= parameter to narrow down the patients returned. You can also query by the gender and date_of_birth fields.

Creating resources

Resources are created by sending a POST to the relevant top-level resouce. For example, to create an appointment, the appointment's information is sent to /api/appointments like this:

import requests

headers = {
    'Authorization': 'Bearer ACCESS_TOKEN',
}
data = {
    'doctor': 1234,
    'duration: 30, # in minutes
    'office': 3456,
    'patient': 5678,
    'scheduled_time: '2014-08-01T14:30:00',
}
url = 'https://drchrono.com/api/appointments'

r = requests.post(url, data=data, headers=headers)

assert r.status_code == 201 # HTTP 201 CREATED

Uploading documents

Uploading a document into a patient's chart is straightforward:

import datetime, json, requests

headers = {
    'Authorization': 'Bearer ACCESS_TOKEN',
}
data = {
    'doctor': 1234,
    'patient': 5678,
    'description': 'Short document description here',
    'date': '2014-02-24',
    'metatags': json.dumps(['tag1', 'tag2']),
}
with open('/path/to/your.pdf', 'rb') as f:
    files = {'document': f}
    requests.post(
        'https://drchrono.com/api/documents',
        data=data, files=files, headers=headers,
    )

iframe integration

Some API apps provide additional functionality for interacting with patient data not offered by drchrono, and can benefit by being incorporated into drchrono's patient information page via iframe. We have created a simple API to make this possible.

To make an existing API application accessible via an iframe on the patient page, contact drchrono support. You will need to provide the pages you need the iframe to appear on (either the patient page or the clinical note page), the URL that the iframe will use for each page, and the height and width they should have. The application will be reviewed before it is approved to ensure that it is functional and secure.

Register a Doctor

iframe applications will appear as choices on the left-hand menu of the patient page for doctors registered with your application. To register a doctor with your application, make a POST request to the /api/iframe_integration endpoint using the access token for the corresponding doctor.

To disable your iframe application for a doctor, make a DELETE request to the same endpoint.

Populating the iframe

There are two places where the iframe can be displayed, either within the patient detail page or the clinical note page, shown below respectively:

Iframe on the patient page

Iframe on the clinical note page

When requesting approval for your iframe app, you must specify a URL for one or both of these pages which will serve as the base URL for your IFrame contents. When a doctor views your iframe, the source URL will have various query parameters appended to it, for example for the patient page the src parameter of the IFrame will be:

<iframe_url>?doctor_id=<doctor_id>&patient_id=<patient_id>&practice_id=<practice_id>&iat=<iat>&jwt=<jwt>

The jwt parameter is crucial if your application transfers any sort of PHI and does not implement its own login system. It encapsulates the other parameters in a JSON web token (JWT) and signs them using SHA-256 HMAC with your client_secret as the key. This verifies that the iframe is being loaded within one of drchrono's pages by an authorized user. In production, you should validate the JWT using an approved library (which are listed on the official site), and only use the parameters extracted from the JWT. Using Python and Django, this might look like:

import jwt

CLIENT_SECRET = <client_secret>
MAX_TIME_DRIFT_SECONDS = 60

def validate_parameters(request):
    token = request.GET['jwt']

    return jwt.decode(token, CLIENT_SECRET, algorithms=['HS256'], leeway=MAX_TIME_DRIFT_SECONDS)

Modern browsers' same-origin policy means that data cannot be passed between your application and drchrono's page through the iframe. Therefore, interaction must happen through the API, using information provided in JWT.