added FHIR evaluate method implementation

etor/src/test/groovy/gov/hhs/cdc/trustedintermediary/external/hapi/HapiFhirEngineImplementationTest.groovy

@@ -4,13 +4,17 @@ import gov.hhs.cdc.trustedintermediary.context.TestApplicationContext
 import gov.hhs.cdc.trustedintermediary.wrappers.HapiFhirEngine
 import org.hl7.fhir.instance.model.api.IBaseResource
 import org.hl7.fhir.r4.model.Bundle
+import org.hl7.fhir.r4.model.DiagnosticReport
+import org.hl7.fhir.r4.model.ServiceRequest
 import org.hl7.fhir.r4.utils.FHIRLexer
 import spock.lang.Specification
 
 // @todo build actual tests this is a skeleton
 class HapiFhirEngineImplementationTest extends Specification {
     HapiFhirEngine engine
     Bundle bundle
+    DiagnosticReport diaReport
+    ServiceRequest servRequest
 
     def setup() {
         TestApplicationContext.reset()
@@ -21,6 +25,19 @@ class HapiFhirEngineImplementationTest extends Specification {
 
         bundle = new Bundle()
         bundle.id = "abc123"
+
+        diaReport = new DiagnosticReport()
+        diaReport.id = "ghi789"
+        servRequest = new ServiceRequest()
+        servRequest.id = "def456"
+
+        def entry1 = new Bundle.BundleEntryComponent()
+        entry1.resource = diaReport
+        bundle.addEntry(entry1)
+
+        def entry2 = new Bundle.BundleEntryComponent()
+        entry2.resource = servRequest
+        bundle.addEntry(entry2)
     }
 
     def cleanup() {
@@ -61,7 +78,7 @@ class HapiFhirEngineImplementationTest extends Specification {
 
     def "parsePath throws FHIRLexerException on fake method"() {
         given:
-        def path = "Bundle.entry.resource.BADMETHOD(MessageHeader)"
+        def path = "Bundle.entry.resource.BadMethod(MessageHeader)"
 
         when:
         engine.parsePath(path)
@@ -124,4 +141,29 @@ class HapiFhirEngineImplementationTest extends Specification {
         then:
         result == false
     }
+
+    def "evaluateCondition throws FHIRLexerException on fake method"() {
+        given:
+        def path = "Bundle.entry[0].resource.BadMethod('blah')"
+
+        when:
+        engine.evaluateCondition(bundle as IBaseResource, path)
+
+        then:
+        thrown(FHIRLexer.FHIRLexerException)
+    }
+
+    def "evaluate returns the correct resource if it's available"() {
+        given:
+        def path = "Bundle.entry.resource.ofType(DiagnosticReport)[0]"
+
+        when:
+        def result = engine.evaluate(bundle as IBaseResource, path)
+
+        then:
+        result.size() == 1
+        result.first().class == DiagnosticReport.class
+        (result.first() as DiagnosticReport).id == diaReport.id
+    }
+
 }

shared/src/main/java/gov/hhs/cdc/trustedintermediary/external/hapi/HapiFhirEngineImplementation.java

@@ -31,6 +31,25 @@ public ExpressionNode parsePath(String fhirPath) {
         return pathEngine.parse(fhirPath);
     }
 
+    public List<Base> evaluate(IBaseResource root, String expression) {
+        var expressionNode = parsePath(expression);
+        var base = (Base) root;
+
+        List<Base> retVal;
+        if (expressionNode == null) {
+            retVal = new ArrayList<>();
+        } else {
+            try {
+                retVal = pathEngine.evaluate(base, expressionNode);
+            } catch (Exception e) {
+                // log exception
+                retVal = new ArrayList<>();
+            }
+        }
+
+        return retVal;
+    }
+
     public Boolean evaluateCondition(IBaseResource root, String expression) throws Exception {
         var expressionNode = parsePath(expression);
         var base = (Base) root;
@@ -51,7 +70,8 @@ public Boolean evaluateCondition(IBaseResource root, String expression) throws E
             // for the purposes of the evaluating a schema condition that is the same as being false
             retVal = false;
         } else {
-            throw new Exception("add here");
+            throw new Exception(
+                    "add here"); // @todo consider defaulting to false and just logging the error
             // throw new FhirParseException("FHIR Path expression did not evaluate to a boolean
             // type: $expression", new Exception());
         }

shared/src/main/java/gov/hhs/cdc/trustedintermediary/wrappers/HapiFhirEngine.java

@@ -1,14 +1,18 @@
 package gov.hhs.cdc.trustedintermediary.wrappers;
 
+import java.util.List;
 import org.hl7.fhir.instance.model.api.IBaseResource;
 import org.hl7.fhir.r4.context.IWorkerContext;
+import org.hl7.fhir.r4.model.Base;
 import org.hl7.fhir.r4.model.ExpressionNode;
 import org.hl7.fhir.r4.utils.FHIRPathEngine;
 
 public interface HapiFhirEngine {
     ExpressionNode parsePath(String fhirPath);
 
-    Boolean evaluateCondition(IBaseResource resource, String expression) throws Exception;
+    List<Base> evaluate(IBaseResource root, String expression);
+
+    Boolean evaluateCondition(IBaseResource root, String expression) throws Exception;
 
     IWorkerContext getContext();