OpenConceptLab/ocl_issues#1761 Add FHIR xml support

core/common/renderers.py

@@ -20,3 +20,7 @@ def render(self, data, accepted_media_type=None, renderer_context=None):
         wrapper = FileWrapper(temp)
         temp.seek(0)
         return wrapper
+
+
+class FhirRenderer(JSONRenderer):
+    media_type = 'application/fhir+json'

core/middlewares/middlewares.py

@@ -1,7 +1,8 @@
 import logging
 import time
 
-from django.http import HttpResponseNotFound
+import requests
+from django.http import HttpResponseNotFound, HttpRequest, HttpResponse
 from request_logging.middleware import LoggingMiddleware
 
 from core.common.constants import VERSION_HEADER, REQUEST_USER_HEADER, RESPONSE_TIME_HEADER, REQUEST_URL_HEADER, \
@@ -83,14 +84,16 @@ def __call__(self, request):
 
 class FhirMiddleware(BaseMiddleware):
     """
-    It is used to expose FHIR endpoints under FHIR subdomain only. If FHIR is not deployed under a dedicated subdomain
-    then FHIR_SUBDOMAIN environment variable should be empty.
+    It is used to expose FHIR endpoints under FHIR subdomain only and convert content from xml to json.
+    If FHIR is not deployed under a dedicated subdomain then FHIR_SUBDOMAIN environment variable should be empty.
     """
 
     def __call__(self, request):
+        absolute_uri = request.build_absolute_uri()
+
         from django.conf import settings
         if settings.FHIR_SUBDOMAIN:
-            uri = request.build_absolute_uri().split('/')
+            uri = absolute_uri.split('/')
             domain = uri[2] if len(uri) > 2 else ''
             is_fhir_domain = domain.startswith(settings.FHIR_SUBDOMAIN + '.')
             resource_type = uri[5] if len(uri) > 5 else None
@@ -104,5 +107,30 @@ def __call__(self, request):
             elif is_fhir_resource:
                 return HttpResponseNotFound()
 
-        response = self.get_response(request)
+        if settings.FHIR_VALIDATOR_URL and ('/CodeSystem/' in absolute_uri or '/ValueSet/' in absolute_uri or
+                                            '/ConceptMap' in absolute_uri):
+            accept_content_type = request.headers.get('Accept')
+            content_type = request.headers.get('Content-Type')
+
+            if content_type.startswith('application/xml') or content_type.startswith('application/fhir+xml'):
+                request.META['CONTENT_TYPE'] = "application/json"
+                if request.method == 'POST' or request.method == 'PUT':
+                    json_request = requests.post(settings.FHIR_VALIDATOR_URL +
+                                                 '/convert?version=4.0&type=xml&toType=json', data=request.body)
+                    request._body = json_request
+
+            if accept_content_type.startswith('application/xml') or \
+                    accept_content_type.startswith('application/fhir+xml'):
+                request.META['HTTP_ACCEPT'] = "application/json"
+
+            response = self.get_response(request)
+
+            if accept_content_type.startswith('application/xml') or \
+                    accept_content_type.startswith('application/fhir+xml'):
+                xml_response = requests.post(settings.FHIR_VALIDATOR_URL + '/convert?version=4.0&type=json&toType=xml',
+                                             data=response.content)
+                response = HttpResponse(xml_response, content_type=accept_content_type)
+        else:
+            response = self.get_response(request)
+
         return response

core/settings.py

@@ -114,6 +114,7 @@
     'DEFAULT_RENDERER_CLASSES': (
         'rest_framework.renderers.JSONRenderer',
         'core.common.renderers.ZippedJSONRenderer',
+        'core.common.renderers.FhirRenderer'
     ),
     'COERCE_DECIMAL_TO_STRING': False,
     'DEFAULT_PAGINATION_CLASS': 'rest_framework.pagination.PageNumberPagination',
@@ -337,6 +338,8 @@
 API_SUPERUSER_PASSWORD = os.environ.get('API_SUPERUSER_PASSWORD', 'Root123')  # password for ocladmin superuser
 API_SUPERUSER_TOKEN = os.environ.get('API_SUPERUSER_TOKEN', '891b4b17feab99f3ff7e5b5d04ccc5da7aa96da6')
 
+FHIR_VALIDATOR_URL = os.environ.get('FHIR_VALIDATOR_URL', None)
+
 # Redis
 REDIS_CONNECTION_OPTIONS = {
     'socket_timeout': 5.0,

docker-compose.yml

@@ -54,8 +54,16 @@ services:
       - AZURE_STORAGE_ACCOUNT_NAME
       - AZURE_STORAGE_CONTAINER_NAME
       - AZURE_STORAGE_CONNECTION_STRING
+      - FHIR_VALIDATOR_URL=${FHIR_VALIDATOR_URL-http://fhir_validator:3500}
     healthcheck:
       test: "curl --silent --fail http://localhost:8000/version/ || exit 1"
+  fhir_validator:
+    image: openconceptlab/validator-wrapper:1.0.53-1deb1a4b
+    restart: "always"
+    ports:
+      - 3500:3500
+    healthcheck:
+      test: "curl --silent --fail http://localhost:3500/ || exit 1"
   celery:
     image: openconceptlab/oclapi2:${ENVIRONMENT-production}
     command: ["bash", "-c", "CELERY_WORKER_NAME=default ./start_celery_worker.sh -P prefork -Q default -c 2"]