Fix False Positives while Checking Referential Integrity

Closes: #2015

Author: alexanderkiel

modules/db/src/blaze/db/impl/batch_db.clj

@@ -190,7 +190,7 @@
   (-rev-include [db resource-handle]
     (let [search-param-registry (:search-param-registry node)
           type (name (type/type resource-handle))
-          reference (codec/v-hash (rh/reference resource-handle))]
+          reference (rh/tid-id resource-handle)]
       (coll/eduction
        (comp
         (mapcat
@@ -203,7 +203,7 @@
        (sr/list-by-target-type search-param-registry type))))
 
   (-rev-include [db resource-handle source-type code]
-    (rev-include db snapshot (codec/v-hash (rh/reference resource-handle))
+    (rev-include db snapshot (rh/tid-id resource-handle)
                  (codec/tid source-type) (codec/c-hash code)))
 
   (-patient-everything [db patient-handle start end]

modules/db/src/blaze/db/impl/index/resource_handle.clj

@@ -121,3 +121,6 @@
 
 (defn local-ref-tuple [{type :fhir/type id :id}]
   [(name type) id])
+
+(defn tid-id [rh]
+  (codec/tid-id (tid rh) (codec/id-byte-string (id rh))))

modules/db/test/blaze/db/api_test.clj

@@ -521,6 +521,24 @@
             :op := :delete
             :num-changes := 2)))))
 
+  (testing "referential integrity checks are not affected by hash collisions"
+    (with-system-data [{:blaze.db/keys [node]} config]
+      [[[:create
+         {:fhir/type :fhir/Encounter
+          :id "A597AEF8855D993D92B063CC69194E33A57F07760034D054150054BCDABFE332"}]
+        [:create
+         {:fhir/type :fhir/Encounter
+          :id "1577C74A3D24F812C29FC372B5B0D9D325AA86A05A541598BF3734247EEAAE5C"}]
+        [:create
+         {:fhir/type :fhir/Observation :id "0"
+          :encounter #fhir/Reference{:reference "Encounter/1577C74A3D24F812C29FC372B5B0D9D325AA86A05A541598BF3734247EEAAE5C"}}]]]
+
+      (testing "deleting the unreferenced encounter succeeds"
+        (let [db @(d/transact node [[:delete "Encounter" "A597AEF8855D993D92B063CC69194E33A57F07760034D054150054BCDABFE332"]])]
+          (given (d/resource-handle db "Encounter" "A597AEF8855D993D92B063CC69194E33A57F07760034D054150054BCDABFE332")
+            :op := :delete
+            :num-changes := 2)))))
+
   (testing "encounter with a condition referencing it"
     (with-system-data [{:blaze.db/keys [node]} config]
       [[[:create {:fhir/type :fhir/Encounter :id "0"}]

modules/db/test/blaze/db/impl/index/resource_handle_spec.clj

@@ -2,6 +2,7 @@
   (:require
    [blaze.byte-buffer :refer [byte-buffer?]]
    [blaze.byte-buffer-spec]
+   [blaze.byte-string :refer [byte-string?]]
    [blaze.db.impl.codec-spec]
    [blaze.db.impl.index.resource-handle :as rh]
    [blaze.db.kv-spec]
@@ -54,3 +55,7 @@
 (s/fdef rh/local-ref-tuple
   :args (s/cat :rh rh/resource-handle?)
   :ret :blaze.fhir/literal-ref-tuple)
+
+(s/fdef rh/tid-id
+  :args (s/cat :rh rh/resource-handle?)
+  :ret byte-string?)