Updates to GraphQL

org.hl7.fhir.dstu3/src/main/java/org/hl7/fhir/dstu3/utils/GraphQLEngine.java

@@ -328,7 +328,7 @@ public class GraphQLEngine implements IGraphQLEngine {
       return obj.primitiveValue() != "";
   }
 
-  private List<Base> filter(Resource context, Property prop, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
+  private List<Base> filter(Resource context, Property prop, String fieldName, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
     List<Base> result = new ArrayList<Base>();
     if (values.size() > 0) {
       int count = Integer.MAX_VALUE;
@@ -353,10 +353,27 @@ public class GraphQLEngine implements IGraphQLEngine {
           fp.append(" and "+arg.getName()+" = '"+vl.get(0).toString()+"'");
         }
       }
+
+      // Account for situations where the GraphQL expression selected e.g.
+      // effectiveDateTime but the field contains effectivePeriod
+      String propName = prop.getName();
+      List<Base> newValues = new ArrayList<>(values.size());
+      for (Base value : values) {
+        if (propName.endsWith("[x]")) {
+          String propNameShortened = propName.substring(0, propName.length() - 3);
+          if (fieldName.startsWith(propNameShortened) && fieldName.length() > propNameShortened.length()) {
+            if (!value.fhirType().equalsIgnoreCase(fieldName.substring(propNameShortened.length()))) {
+              continue;
+            }
+          }
+        }
+        newValues.add(value);
+      }
+
       int i = 0;
       int t = 0;
       if (fp.length() == 0)
-        for (Base v : values) {
+        for (Base v : newValues) {
           if ((i >= offset) && passesExtensionMode(v, extensionMode)) {
             result.add(v);
             t++;
@@ -365,8 +382,8 @@ public class GraphQLEngine implements IGraphQLEngine {
           }
           i++;
         } else {
-          ExpressionNode node = fpe.parse(fp.toString().substring(5));
+          ExpressionNode node = fpe.parse(fp.substring(5));
-          for (Base v : values) {
+          for (Base v : newValues) {
             if ((i >= offset) && passesExtensionMode(v, extensionMode) && fpe.evaluateToBoolean(null, context, v, node)) {
               result.add(v);
               t++;
@@ -526,7 +543,7 @@ public class GraphQLEngine implements IGraphQLEngine {
             if (!isPrimitive(prop.getTypeCode()) && sel.getField().getName().startsWith("_"))
               throw new EGraphQLException("Unknown property "+sel.getField().getName()+" on "+source.fhirType());
 
-            List<Base> vl = filter(context, prop, sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
+            List<Base> vl = filter(context, prop, sel.getField().getName(), sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
             if (!vl.isEmpty())
               processValues(context, sel, prop, target, vl, sel.getField().getName().startsWith("_"), inheritedList, suffix);
           }

org.hl7.fhir.r4/src/main/java/org/hl7/fhir/r4/utils/GraphQLEngine.java

@@ -190,7 +190,7 @@ public class GraphQLEngine implements IGraphQLEngine {
       return obj.primitiveValue() != "";
   }
 
-  private List<Base> filter(Resource context, Property prop, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
+  private List<Base> filter(Resource context, Property prop, String fieldName, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
     List<Base> result = new ArrayList<Base>();
     if (values.size() > 0) {
       int count = Integer.MAX_VALUE;
@@ -215,10 +215,28 @@ public class GraphQLEngine implements IGraphQLEngine {
           fp.append(" and " + arg.getName() + " = '" + vl.get(0).toString() + "'");
         }
       }
+
+      // Account for situations where the GraphQL expression selected e.g.
+      // effectiveDateTime but the field contains effectivePeriod
+      String propName = prop.getName();
+      List<Base> newValues = new ArrayList<>(values.size());
+      for (Base value : values) {
+        if (propName.endsWith("[x]")) {
+          String propNameShortened = propName.substring(0, propName.length() - 3);
+          if (fieldName.startsWith(propNameShortened) && fieldName.length() > propNameShortened.length()) {
+            if (!value.fhirType().equalsIgnoreCase(fieldName.substring(propNameShortened.length()))) {
+              continue;
+            }
+          }
+        }
+        newValues.add(value);
+      }
+
       int i = 0;
       int t = 0;
       if (fp.length() == 0)
-        for (Base v : values) {
+        for (Base v : newValues) {
+
           if ((i >= offset) && passesExtensionMode(v, extensionMode)) {
             result.add(v);
             t++;
@@ -228,8 +246,8 @@ public class GraphQLEngine implements IGraphQLEngine {
           i++;
         }
       else {
-        ExpressionNode node = fpe.parse(fp.toString().substring(5));
+        ExpressionNode node = fpe.parse(fp.substring(5));
-        for (Base v : values) {
+        for (Base v : newValues) {
           if ((i >= offset) && passesExtensionMode(v, extensionMode) && fpe.evaluateToBoolean(null, context, v, node)) {
             result.add(v);
             t++;
@@ -389,7 +407,7 @@ public class GraphQLEngine implements IGraphQLEngine {
             if (!isPrimitive(prop.getTypeCode()) && sel.getField().getName().startsWith("_"))
               throw new EGraphQLException("Unknown property " + sel.getField().getName() + " on " + source.fhirType());
 
-            List<Base> vl = filter(context, prop, sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
+            List<Base> vl = filter(context, prop, sel.getField().getName(), sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
             if (!vl.isEmpty())
               processValues(context, sel, prop, target, vl, sel.getField().getName().startsWith("_"), inheritedList, suffix);
           }

org.hl7.fhir.r4/src/test/resources/graphql/manifest.xml

@@ -3,6 +3,7 @@
  <test name="filter-fhirpath" source="filter-fhirpath.gql" output="filter-fhirpath.json" context="Patient/example/$graphql"/>
  <test name="using wrong field" source="wrong-field.gql" output="$error" context="Patient/example/$graphql"/>
  <test name="polymorphic" source="polymorphic.gql" output="polymorphic.json" context="Observation/example/$graphql"/>
+ <test name="polymorphic-difftype" source="polymorphic-difftype.gql" output="polymorphic-difftype.json" context="Observation/example/$graphql"/>
  <test name="reference" source="reference.gql" output="reference.json" context="Observation/example/$graphql"/>
  <test name="reference-type-in" source="reference-type-in.gql" output="reference-type-in.json" context="Observation/example/$graphql"/>
  <test name="reference-type-out" source="reference-type-out.gql" output="reference-type-out.json" context="Observation/example/$graphql"/>

org.hl7.fhir.r4/src/test/resources/graphql/polymorphic-difftype.gql

@@ -0,0 +1,5 @@
+{
+  subject{reference}
+  valueQuantity {value unit}
+}
+

org.hl7.fhir.r4/src/test/resources/graphql/polymorphic-difftype.json

@@ -0,0 +1,6 @@
+{
+  "subject" : {
+    "reference" : "Patient/example"
+  },
+  "valueString": "FOO"
+}

org.hl7.fhir.r4b/src/main/java/org/hl7/fhir/r4b/utils/GraphQLEngine.java

@@ -356,7 +356,7 @@ public class GraphQLEngine implements IGraphQLEngine {
       return obj.primitiveValue() != "";
   }
 
-  private List<Base> filter(Resource context, Property prop, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
+  private List<Base> filter(Resource context, Property prop, String fieldName, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
     List<Base> result = new ArrayList<Base>();
     if (values.size() > 0) {
       int count = Integer.MAX_VALUE;
@@ -381,10 +381,28 @@ public class GraphQLEngine implements IGraphQLEngine {
           fp.append(" and "+arg.getName()+" = '"+vl.get(0).toString()+"'");
         }
       }
+
+
+      // Account for situations where the GraphQL expression selected e.g.
+      // effectiveDateTime but the field contains effectivePeriod
+      String propName = prop.getName();
+      List<Base> newValues = new ArrayList<>(values.size());
+      for (Base value : values) {
+        if (propName.endsWith("[x]")) {
+          String propNameShortened = propName.substring(0, propName.length() - 3);
+          if (fieldName.startsWith(propNameShortened) && fieldName.length() > propNameShortened.length()) {
+            if (!value.fhirType().equalsIgnoreCase(fieldName.substring(propNameShortened.length()))) {
+              continue;
+            }
+          }
+        }
+        newValues.add(value);
+      }
+
       int i = 0;
       int t = 0;
       if (fp.length() == 0)
-        for (Base v : values) {
+        for (Base v : newValues) {
           if ((i >= offset) && passesExtensionMode(v, extensionMode)) {
             result.add(v);
             t++;
@@ -393,8 +411,8 @@ public class GraphQLEngine implements IGraphQLEngine {
           }
           i++;
         } else {
-          ExpressionNode node = fpe.parse(fp.toString().substring(5));
+          ExpressionNode node = fpe.parse(fp.substring(5));
-          for (Base v : values) {
+          for (Base v : newValues) {
             if ((i >= offset) && passesExtensionMode(v, extensionMode) && fpe.evaluateToBoolean(null, context, v, node)) {
               result.add(v);
               t++;
@@ -554,7 +572,7 @@ public class GraphQLEngine implements IGraphQLEngine {
             if (!isPrimitive(prop.getTypeCode()) && sel.getField().getName().startsWith("_"))
               throw new EGraphQLException("Unknown property "+sel.getField().getName()+" on "+source.fhirType());
 
-            List<Base> vl = filter(context, prop, sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
+            List<Base> vl = filter(context, prop, sel.getField().getName(), sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
             if (!vl.isEmpty())
               processValues(context, sel, prop, target, vl, sel.getField().getName().startsWith("_"), inheritedList, suffix);
           }

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/GraphQLEngine.java

@@ -356,7 +356,7 @@ public class GraphQLEngine implements IGraphQLEngine {
       return obj.primitiveValue() != "";
   }
 
-  private List<Base> filter(Resource context, Property prop, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
+  private List<Base> filter(Resource context, Property prop, String fieldName, List<Argument> arguments, List<Base> values, boolean extensionMode) throws FHIRException, EGraphQLException {
     List<Base> result = new ArrayList<Base>();
     if (values.size() > 0) {
       int count = Integer.MAX_VALUE;
@@ -381,10 +381,27 @@ public class GraphQLEngine implements IGraphQLEngine {
           fp.append(" and "+arg.getName()+" = '"+vl.get(0).toString()+"'");
         }
       }
+
+      // Account for situations where the GraphQL expression selected e.g.
+      // effectiveDateTime but the field contains effectivePeriod
+      String propName = prop.getName();
+      List<Base> newValues = new ArrayList<>(values.size());
+      for (Base value : values) {
+        if (propName.endsWith("[x]")) {
+          String propNameShortened = propName.substring(0, propName.length() - 3);
+          if (fieldName.startsWith(propNameShortened) && fieldName.length() > propNameShortened.length()) {
+            if (!value.fhirType().equalsIgnoreCase(fieldName.substring(propNameShortened.length()))) {
+              continue;
+            }
+          }
+        }
+        newValues.add(value);
+      }
+
       int i = 0;
       int t = 0;
       if (fp.length() == 0)
-        for (Base v : values) {
+        for (Base v : newValues) {
           if ((i >= offset) && passesExtensionMode(v, extensionMode)) {
             result.add(v);
             t++;
@@ -393,8 +410,8 @@ public class GraphQLEngine implements IGraphQLEngine {
           }
           i++;
         } else {
-          ExpressionNode node = fpe.parse(fp.toString().substring(5));
+          ExpressionNode node = fpe.parse(fp.substring(5));
-          for (Base v : values) {
+          for (Base v : newValues) {
             if ((i >= offset) && passesExtensionMode(v, extensionMode) && fpe.evaluateToBoolean(null, context, v, node)) {
               result.add(v);
               t++;
@@ -554,7 +571,7 @@ public class GraphQLEngine implements IGraphQLEngine {
             if (!isPrimitive(prop.getTypeCode()) && sel.getField().getName().startsWith("_"))
               throw new EGraphQLException("Unknown property "+sel.getField().getName()+" on "+source.fhirType());
 
-            List<Base> vl = filter(context, prop, sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
+            List<Base> vl = filter(context, prop, sel.getField().getName(), sel.getField().getArguments(), prop.getValues(), sel.getField().getName().startsWith("_"));
             if (!vl.isEmpty())
               processValues(context, sel, prop, target, vl, sel.getField().getName().startsWith("_"), inheritedList, suffix);
           }

org.hl7.fhir.r5/src/main/java/org/hl7/fhir/r5/utils/GraphQLSchemaGenerator.java

@@ -30,24 +30,10 @@ package org.hl7.fhir.r5.utils;
  */
 
 
-
 // todo:
 // - generate sort order parameters
 // - generate inherited search parameters
 
-import java.io.BufferedWriter;
-import java.io.IOException;
-import java.io.OutputStream;
-import java.io.OutputStreamWriter;
-import java.util.ArrayList;
-import java.util.Collections;
-import java.util.EnumSet;
-import java.util.HashSet;
-import java.util.HashMap;
-import java.util.List;
-import java.util.Map;
-import java.util.Set;
-
 import org.hl7.fhir.exceptions.FHIRException;
 import org.hl7.fhir.r5.conformance.ProfileUtilities;
 import org.hl7.fhir.r5.context.IWorkerContext;
@@ -60,21 +46,32 @@ import org.hl7.fhir.r5.model.StructureDefinition.StructureDefinitionKind;
 import org.hl7.fhir.r5.model.StructureDefinition.TypeDerivationRule;
 import org.hl7.fhir.utilities.Utilities;
 
+import java.io.BufferedWriter;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.Writer;
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.EnumSet;
+import java.util.HashMap;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+
+import static java.util.Objects.requireNonNull;
+
 public class GraphQLSchemaGenerator {
 
-  public enum FHIROperationType {READ, SEARCH, CREATE, UPDATE, DELETE};
-  
-  private static final String INNER_TYPE_NAME = "gql.type.name";
   private static final Set<String> JSON_NUMBER_TYPES = new HashSet<String>() {{
     add("decimal");
     add("positiveInt");
     add("unsignedInt");
   }};
-
+  private final ProfileUtilities profileUtilities;
+  private final String version;
   IWorkerContext context;
-  private ProfileUtilities profileUtilities;
-  private String version;
-
   public GraphQLSchemaGenerator(IWorkerContext context, String version) {
     super();
     this.context = context;
@@ -84,9 +81,15 @@ public class GraphQLSchemaGenerator {
 
   public void generateTypes(OutputStream stream) throws IOException, FHIRException {
     BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(stream));
+    generateTypes(writer);
+    writer.flush();
+    writer.close();
+  }
 
-    Map<String, StructureDefinition> pl = new HashMap<String, StructureDefinition>();
+  public void generateTypes(Writer writer) throws IOException {
-    Map<String, StructureDefinition> tl = new HashMap<String, StructureDefinition>();
+    Map<String, StructureDefinition> pl = new HashMap<>();
+    Map<String, StructureDefinition> tl = new HashMap<>();
+    Map<String, String> existingTypeNames = new HashMap<>();
     for (StructureDefinition sd : context.allStructures()) {
       if (sd.getKind() == StructureDefinitionKind.PRIMITIVETYPE && sd.getDerivation() == TypeDerivationRule.SPECIALIZATION) {
         pl.put(sd.getName(), sd);
@@ -102,22 +105,32 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
     writer.write("# FHIR Defined Search Parameter Types\r\n");
     for (SearchParamType dir : SearchParamType.values()) {
+      if (pl.containsKey(dir.toCode())) {
+        // Don't double create String and URI
+        continue;
+      }
       if (dir != SearchParamType.NULL)
         generateSearchParamType(writer, dir.toCode());
     }
     writer.write("\r\n");
     generateElementBase(writer);
     for (String n : sorted(tl.keySet()))
-      generateType(writer, tl.get(n));
+      generateType(existingTypeNames, writer, tl.get(n));
-    writer.flush();
-    writer.close();
   }
 
   public void generateResource(OutputStream stream, StructureDefinition sd, List<SearchParameter> parameters, EnumSet<FHIROperationType> operations) throws IOException, FHIRException {
     BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(stream));
+    generateResource(writer, sd, parameters, operations);
+    writer.flush();
+    writer.close();
+  }
+
+  public void generateResource(Writer writer, StructureDefinition sd, List<SearchParameter> parameters, EnumSet<FHIROperationType> operations) throws IOException {
+    Map<String, String> existingTypeNames = new HashMap<>();
+
     writer.write("# FHIR GraphQL Schema. Version " + version + "\r\n\r\n");
     writer.write("# import * from 'types.graphql'\r\n\r\n");
-    generateType(writer, sd);
+    generateType(existingTypeNames, writer, sd);
     if (operations.contains(FHIROperationType.READ))
       generateIdAccess(writer, sd.getName());
     if (operations.contains(FHIROperationType.SEARCH)) {
@@ -130,11 +143,9 @@ public class GraphQLSchemaGenerator {
       generateUpdate(writer, sd.getName());
     if (operations.contains(FHIROperationType.DELETE))
       generateDelete(writer, sd.getName());
-    writer.flush();
-    writer.close();
   }
 
-  private void generateCreate(BufferedWriter writer, String name) throws IOException {
+  private void generateCreate(Writer writer, String name) throws IOException {
     writer.write("type " + name + "CreateType {\r\n");
     writer.write("  " + name + "Create(");
     param(writer, "resource", name + "Input", false, false);
@@ -149,7 +160,7 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
-  private void generateUpdate(BufferedWriter writer, String name) throws IOException {
+  private void generateUpdate(Writer writer, String name) throws IOException {
     writer.write("type " + name + "UpdateType {\r\n");
     writer.write("  " + name + "Update(");
     param(writer, "id", "ID", false, false);
@@ -165,7 +176,7 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
-  private void generateDelete(BufferedWriter writer, String name) throws IOException {
+  private void generateDelete(Writer writer, String name) throws IOException {
     writer.write("type " + name + "DeleteType {\r\n");
     writer.write("  " + name + "Delete(");
     param(writer, "id", "ID", false, false);
@@ -178,21 +189,26 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
-  private void generateListAccess(BufferedWriter writer, List<SearchParameter> parameters, String name) throws IOException {
+  private void generateListAccess(Writer writer, List<SearchParameter> parameters, String name) throws IOException {
     writer.write("type " + name + "ListType {\r\n");
-    writer.write("  "+name+"List(");
+    writer.write("  ");
-    param(writer, "_filter", "String", false, false);
+    generateListAccessQuery(writer, parameters, name);
-    for (SearchParameter sp : parameters)
-      param(writer, sp.getName().replace("-", "_"), getGqlname(sp.getType().toCode()), true, true);
-    param(writer, "_sort", "String", false, true);
-    param(writer, "_count", "Int", false, true);
-    param(writer, "_cursor", "String", false, true);
-    writer.write("): ["+name+"]\r\n");
     writer.write("}\r\n");
     writer.write("\r\n");
   }
 
-  private void param(BufferedWriter writer, String name, String type, boolean list, boolean line) throws IOException {
+  public void generateListAccessQuery(Writer writer, List<SearchParameter> parameters, String name) throws IOException {
+    writer.write(name + "List(");
+    param(writer, "_filter", "String", false, false);
+    for (SearchParameter sp : parameters)
+      param(writer, sp.getName().replace("-", "_"), getGqlname(requireNonNull(sp.getType().toCode())), true, true);
+    param(writer, "_sort", "String", false, true);
+    param(writer, "_count", "Int", false, true);
+    param(writer, "_cursor", "String", false, true);
+    writer.write("): [" + name + "]\r\n");
+  }
+
+  private void param(Writer writer, String name, String type, boolean list, boolean line) throws IOException {
     if (line)
       writer.write("\r\n    ");
     writer.write(name);
@@ -204,16 +220,10 @@ public class GraphQLSchemaGenerator {
       writer.write("]");
   }
 
-  private void generateConnectionAccess(BufferedWriter writer, List<SearchParameter> parameters, String name) throws IOException {
+  private void generateConnectionAccess(Writer writer, List<SearchParameter> parameters, String name) throws IOException {
     writer.write("type " + name + "ConnectionType {\r\n");
-    writer.write("  "+name+"Conection(");
+    writer.write("  ");
-    param(writer, "_filter", "String", false, false);
+    generateConnectionAccessQuery(writer, parameters, name);
-    for (SearchParameter sp : parameters)
-      param(writer, sp.getName().replace("-", "_"), getGqlname(sp.getType().toCode()), true, true);
-    param(writer, "_sort", "String", false, true);
-    param(writer, "_count", "Int", false, true);
-    param(writer, "_cursor", "String", false, true);
-    writer.write("): "+name+"Connection\r\n");
     writer.write("}\r\n");
     writer.write("\r\n");
     writer.write("type " + name + "Connection {\r\n");
@@ -235,15 +245,25 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
+  public void generateConnectionAccessQuery(Writer writer, List<SearchParameter> parameters, String name) throws IOException {
+    writer.write(name + "Conection(");
+    param(writer, "_filter", "String", false, false);
+    for (SearchParameter sp : parameters)
+      param(writer, sp.getName().replace("-", "_"), getGqlname(requireNonNull(sp.getType().toCode())), true, true);
+    param(writer, "_sort", "String", false, true);
+    param(writer, "_count", "Int", false, true);
+    param(writer, "_cursor", "String", false, true);
+    writer.write("): " + name + "Connection\r\n");
+  }
 
-  private void generateIdAccess(BufferedWriter writer, String name) throws IOException {
+  private void generateIdAccess(Writer writer, String name) throws IOException {
     writer.write("type " + name + "ReadType {\r\n");
     writer.write("  " + name + "(id: ID!): " + name + "\r\n");
     writer.write("}\r\n");
     writer.write("\r\n");
   }
 
-  private void generateElementBase(BufferedWriter writer) throws IOException {
+  private void generateElementBase(Writer writer) throws IOException {
     writer.write("type ElementBase {\r\n");
     writer.write("  id: ID\r\n");
     writer.write("  extension: [Extension]\r\n");
@@ -257,18 +277,18 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
-  private void generateType(BufferedWriter writer, StructureDefinition sd) throws IOException {
+  private void generateType(Map<String, String> existingTypeNames, Writer writer, StructureDefinition sd) throws IOException {
     if (sd.getAbstract())
       return;
 
-    List<StringBuilder> list = new ArrayList<StringBuilder>();
+    List<StringBuilder> list = new ArrayList<>();
     StringBuilder b = new StringBuilder();
     list.add(b);
     b.append("type ");
     b.append(sd.getName());
     b.append(" {\r\n");
     ElementDefinition ed = sd.getSnapshot().getElementFirstRep();
-    generateProperties(list, b, sd.getName(), sd, ed, "type", "");
+    generateProperties(existingTypeNames, list, b, sd.getName(), sd, ed, "type", "");
     b.append("}");
     b.append("\r\n");
     b.append("\r\n");
@@ -281,7 +301,7 @@ public class GraphQLSchemaGenerator {
     b.append(sd.getName());
     b.append("Input {\r\n");
     ed = sd.getSnapshot().getElementFirstRep();
-    generateProperties(list, b, sd.getName(), sd, ed, "input", "Input");
+    generateProperties(existingTypeNames, list, b, sd.getName(), sd, ed, "input", "Input");
     b.append("}");
     b.append("\r\n");
     b.append("\r\n");
@@ -289,22 +309,22 @@ public class GraphQLSchemaGenerator {
       writer.write(bs.toString());
   }
 
-  private void generateProperties(List<StringBuilder> list, StringBuilder b, String typeName, StructureDefinition sd, ElementDefinition ed, String mode, String suffix) throws IOException {
+  private void generateProperties(Map<String, String> existingTypeNames, List<StringBuilder> list, StringBuilder b, String typeName, StructureDefinition sd, ElementDefinition ed, String mode, String suffix) throws IOException {
     List<ElementDefinition> children = profileUtilities.getChildList(sd, ed);
     for (ElementDefinition child : children) {
       if (child.hasContentReference()) {
         ElementDefinition ref = resolveContentReference(sd, child.getContentReference());
-        generateProperty(list, b, typeName, sd, child, ref.getType().get(0), false, ref, mode, suffix);
+        generateProperty(existingTypeNames, list, b, typeName, sd, child, ref.getType().get(0), false, ref, mode, suffix);
       } else if (child.getType().size() == 1) {
-        generateProperty(list, b, typeName, sd, child, child.getType().get(0), false, null, mode, suffix);
+        generateProperty(existingTypeNames, list, b, typeName, sd, child, child.getType().get(0), false, null, mode, suffix);
       } else {
         boolean ref = false;
         for (TypeRefComponent t : child.getType()) {
           if (!t.hasTarget())
-            generateProperty(list, b, typeName, sd, child, t, true, null, mode, suffix);
+            generateProperty(existingTypeNames, list, b, typeName, sd, child, t, true, null, mode, suffix);
           else if (!ref) {
             ref = true;
-            generateProperty(list, b, typeName, sd, child, t, true, null, mode, suffix);
+            generateProperty(existingTypeNames, list, b, typeName, sd, child, t, true, null, mode, suffix);
           }
         }
       }
@@ -320,7 +340,7 @@ public class GraphQLSchemaGenerator {
     throw new Error("Unable to find " + id);
   }
 
-  private void generateProperty(List<StringBuilder> list, StringBuilder b, String typeName, StructureDefinition sd, ElementDefinition child, TypeRefComponent typeDetails, boolean suffix, ElementDefinition cr, String mode, String suffixS) throws IOException {
+  private void generateProperty(Map<String, String> existingTypeNames, List<StringBuilder> list, StringBuilder b, String typeName, StructureDefinition sd, ElementDefinition child, TypeRefComponent typeDetails, boolean suffix, ElementDefinition cr, String mode, String suffixS) throws IOException {
     if (isPrimitive(typeDetails)) {
       String n = getGqlname(typeDetails.getWorkingCode());
       b.append("  ");
@@ -355,11 +375,11 @@ public class GraphQLSchemaGenerator {
         b.append("[");
       String type = typeDetails.getWorkingCode();
       if (cr != null)
-        b.append(generateInnerType(list, sd, typeName, cr, mode, suffixS));
+        b.append(generateInnerType(existingTypeNames, list, sd, typeName, cr, mode, suffixS));
       else if (Utilities.existsInList(type, "Element", "BackboneElement"))
-        b.append(generateInnerType(list, sd, typeName, child, mode, suffixS));
+        b.append(generateInnerType(existingTypeNames, list, sd, typeName, child, mode, suffixS));
       else
-        b.append(type+suffixS);
+        b.append(type).append(suffixS);
       if (!child.getMax().equals("1"))
         b.append("]");
       if (child.getMin() != 0 && !suffix)
@@ -368,12 +388,15 @@ public class GraphQLSchemaGenerator {
     }
   }
 
-  private String generateInnerType(List<StringBuilder> list, StructureDefinition sd, String name, ElementDefinition child, String mode, String suffix) throws IOException {
+  private String generateInnerType(Map<String, String> existingTypeNames, List<StringBuilder> list, StructureDefinition sd, String name, ElementDefinition child, String mode, String suffix) throws IOException {
-    if (child.hasUserData(INNER_TYPE_NAME+"."+mode))
+    String key = child.getName() + "." + mode;
-      return child.getUserString(INNER_TYPE_NAME+"."+mode);
+    if (existingTypeNames.containsKey(key)) {
+      return existingTypeNames.get(key);
+    }
+
+    String typeName = name + Utilities.capitalize(tail(child.getPath(), false)) + suffix;
+    existingTypeNames.put(key, typeName + suffix);
 
-    String typeName = name+Utilities.capitalize(tail(child.getPath(), false));
-    child.setUserData(INNER_TYPE_NAME+"."+mode, typeName);
     StringBuilder b = new StringBuilder();
     list.add(b);
     b.append(mode);
@@ -381,7 +404,7 @@ public class GraphQLSchemaGenerator {
     b.append(typeName);
     b.append(suffix);
     b.append(" {\r\n");
-    generateProperties(list, b, typeName, sd, child, mode, suffix);
+    generateProperties(existingTypeNames, list, b, typeName, sd, child, mode, suffix);
     b.append("}");
     b.append("\r\n");
     b.append("\r\n");
@@ -404,13 +427,12 @@ public class GraphQLSchemaGenerator {
   }
 
   private List<String> sorted(Set<String> keys) {
-    List<String> sl = new ArrayList<>();
+    List<String> sl = new ArrayList<>(keys);
-    sl.addAll(keys);
     Collections.sort(sl);
     return sl;
   }
 
-  private void generatePrimitive(BufferedWriter writer, StructureDefinition sd) throws IOException, FHIRException {
+  private void generatePrimitive(Writer writer, StructureDefinition sd) throws IOException, FHIRException {
     String gqlName = getGqlname(sd.getName());
     if (gqlName.equals(sd.getName())) {
       writer.write("scalar ");
@@ -426,7 +448,7 @@ public class GraphQLSchemaGenerator {
     writer.write("\r\n");
   }
 
-  private void generateSearchParamType(BufferedWriter writer, String name) throws IOException, FHIRException {
+  private void generateSearchParamType(Writer writer, String name) throws IOException, FHIRException {
     String gqlName = getGqlname(name);
     if (gqlName.equals("date")) {
       writer.write("# Search Param ");
@@ -469,4 +491,6 @@ public class GraphQLSchemaGenerator {
       return "ID";
     return name;
   }
+
+  public enum FHIROperationType {READ, SEARCH, CREATE, UPDATE, DELETE}
 }