fix: avoid iterating over a None entry result for an empty search

Also, avoid a deprecation warning for perform_iter()

Fixes #185

Author: mikix

fhirclient/_utils.py

@@ -1,9 +1,7 @@
 import urllib
 from typing import Optional
 
-import requests
-
-from typing import TYPE_CHECKING, Iterable
+from typing import TYPE_CHECKING, Iterator
 
 if TYPE_CHECKING:
     from fhirclient.server import FHIRServer
@@ -92,7 +90,7 @@ def _execute_pagination_request(sanitized_url: str, server: 'FHIRServer') -> 'Bu
     return Bundle.read_from(sanitized_url, server)
 
 
-def iter_pages(first_bundle: 'Bundle', server: 'FHIRServer') -> Iterable['Bundle']:
+def iter_pages(first_bundle: 'Bundle', server: 'FHIRServer') -> Iterator['Bundle']:
     """
     Iterator that yields each page of results as a FHIR Bundle.
 

fhirclient/client.py

@@ -1,7 +1,7 @@
 import logging
 from .server import FHIRServer, FHIRUnauthorizedException, FHIRNotFoundException
 
-__version__ = '4.3.0'
+__version__ = '4.3.1'
 __author__ = 'SMART Platforms Team'
 __license__ = 'APACHE2'
 __copyright__ = "Copyright 2017 Boston Children's Hospital"

fhirclient/models/fhirsearch.py

@@ -14,7 +14,7 @@
 
 try:
     from urllib import quote_plus
-except Exception as e:
+except ImportError:
     from urllib.parse import quote_plus
 
 if TYPE_CHECKING:
@@ -117,7 +117,19 @@ def include(self, reference_field, reference_model=None, reverse=False):
 
         self.includes.append((reference_model, reference_field, reverse))
         return self
-    
+
+    def _read_bundle(self, server) -> 'Bundle':
+        """ Construct the search URL and execute it against the given server.
+
+        :param server: The server against which to perform the search
+        :returns: A Bundle resource
+        """
+        if server is None:
+            raise Exception("Need a server to perform search")
+
+        from .bundle import Bundle
+        return Bundle.read_from(self.construct(), server)
+
     def perform(self, server) -> 'Bundle':
         """ Construct the search URL and execute it against the given server.
         
@@ -131,11 +143,7 @@ def perform(self, server) -> 'Bundle':
             DeprecationWarning,
         )
 
-        if server is None:
-            raise Exception("Need a server to perform search")
-
-        from .bundle import Bundle
-        return Bundle.read_from(self.construct(), server)
+        return self._read_bundle(server)
 
     # Use forward references to avoid circular imports
     def perform_iter(self, server) -> Iterator['Bundle']:
@@ -145,7 +153,7 @@ def perform_iter(self, server) -> Iterator['Bundle']:
         :param server: The server against which to perform the search
         :returns: An iterator of Bundle instances
         """
-        return iter_pages(self.perform(server), server)
+        return iter_pages(self._read_bundle(server), server)
 
     def perform_resources(self, server) -> 'list[Resource]':
         """ Performs the search by calling `perform_resources_iter` and returns a list of Resource instances.
@@ -171,8 +179,10 @@ def perform_resources_iter(self, server) -> Iterator['Resource']:
         :returns: An iterator of Resource instances
         """
         for bundle in self.perform_iter(server):
-            for entry in bundle.entry:
-                yield entry.resource
+            entries = bundle.entry or []
+            for entry in entries:
+                if entry.resource:
+                    yield entry.resource
 
 
 class FHIRSearchParam(object):
@@ -205,7 +215,7 @@ def handle(self):
         return handler.handle(self.copy())
 
     def as_parameter(self):
-        """ Return a string that represents the reciever as "key=value".
+        """ Return a string that represents the receiver as "key=value".
         """
         return '{}={}'.format(self.name, quote_plus(self.value, safe=',<=>'))
 

tests/models/fhirsearch_perform_iter_test.py

@@ -240,6 +240,40 @@ def test_perform_resources_iter_multiple_pages(self):
         self.assertEqual(result[1].id, "3124")
         self.assertEqual(result[2].id, "3125")
 
+    @responses.activate
+    def test_perform_resources_iter_null_bundle(self):
+        """This happens when no results are found for a search."""
+        # Mock the network response for the initial search request
+        bundle_content = {
+            "resourceType": "Bundle",
+            "type": "searchset",
+            "entry": None,
+        }
+
+        # Mock the single page response
+        self.add_mock_response("https://example.com/Bundle?patient=347&_count=1", bundle_content)
+
+        # Call perform_resources_iter with the server URL
+        result = list(self.search.perform_resources_iter(self.mock_server))
+        self.assertEqual(result, [])
+
+    @responses.activate
+    def test_perform_resources_iter_null_resource(self):
+        """This shouldn't happen for search results, but the spec allows .resource to be empty"""
+        # Mock the network response for the initial search request
+        bundle_content = {
+            "resourceType": "Bundle",
+            "type": "searchset",
+            "entry": [{}],
+        }
+
+        # Mock the single page response
+        self.add_mock_response("https://example.com/Bundle?patient=347&_count=1", bundle_content)
+
+        # Call perform_resources_iter with the server URL
+        result = list(self.search.perform_resources_iter(self.mock_server))
+        self.assertEqual(result, [])
+
 
 # Network-level Mocking
 class MockServer(server.FHIRServer):