[(master)] Added support for extensions in Meta resource

hapi-fhir-base/src/main/java/ca/uhn/fhir/model/api/ResourceMetadataKeyEnum.java

@@ -614,4 +614,29 @@ public abstract class ResourceMetadataKeyEnum<T> implements Serializable {
 
 	}
 
+	public static final class ExtensionResourceMetadataKey extends ResourceMetadataKeyEnum<ExtensionDt> {
+		public ExtensionResourceMetadataKey(String url) {
+			super(url);
+		}
+
+		@Override
+		public ExtensionDt get(IResource theResource) {
+			Object retValObj = theResource.getResourceMetadata().get(this);
+			if (retValObj == null) {
+				return null;
+			} else if (retValObj instanceof ExtensionDt) {
+				return (ExtensionDt) retValObj;
+			}
+			throw new InternalErrorException("Found an object of type '" + retValObj.getClass().getCanonicalName()
+				+ "' in resource metadata for key " + this.name() + " - Expected "
+				+ ExtensionDt.class.getCanonicalName());
+		}
+
+		@Override
+		public void put(IResource theResource, ExtensionDt theObject) {
+			theResource.getResourceMetadata().put(this, theObject);
+		}
+	}
+
+	
 }

hapi-fhir-base/src/main/java/ca/uhn/fhir/parser/BaseParser.java

@@ -911,6 +911,18 @@ public abstract class BaseParser implements IParser {
 		throw new DataFormatException(nextChild + " has no child of type " + theType);
 	}
 
+	protected List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> getExtensionMetadataKeys(IResource resource) {
+		List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> extensionMetadataKeys = new ArrayList<Map.Entry<ResourceMetadataKeyEnum<?>, Object>>();
+		for (Map.Entry<ResourceMetadataKeyEnum<?>, Object> entry : resource.getResourceMetadata().entrySet()) {
+			if (entry.getKey() instanceof ResourceMetadataKeyEnum.ExtensionResourceMetadataKey) {
+				extensionMetadataKeys.add(entry);
+			}
+		}
+
+		return extensionMetadataKeys;
+	}
+
+
 	protected static <T> List<T> extractMetadataListNotNull(IResource resource, ResourceMetadataKeyEnum<List<T>> key) {
 		List<? extends T> securityLabels = key.get(resource);
 		if (securityLabels == null) {

hapi-fhir-base/src/main/java/ca/uhn/fhir/parser/JsonParser.java

@@ -655,8 +655,9 @@ public class JsonParser extends BaseParser implements IJsonLikeParser {
 			if (isBlank(versionIdPart)) {
 				versionIdPart = ResourceMetadataKeyEnum.VERSION.get(resource);
 			}
+			List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> extensionMetadataKeys = getExtensionMetadataKeys(resource);
 
-			if (super.shouldEncodeResourceMeta(resource) && ElementUtil.isEmpty(versionIdPart, updated, securityLabels, tags, profiles) == false) {
+			if (super.shouldEncodeResourceMeta(resource) && (ElementUtil.isEmpty(versionIdPart, updated, securityLabels, tags, profiles) == false) || !extensionMetadataKeys.isEmpty()) {
 				beginObject(theEventWriter, "meta");
 				writeOptionalTagWithTextNode(theEventWriter, "versionId", versionIdPart);
 				writeOptionalTagWithTextNode(theEventWriter, "lastUpdated", updated);
@@ -696,6 +697,8 @@ public class JsonParser extends BaseParser implements IJsonLikeParser {
 					theEventWriter.endArray();
 				}
 
+				addExtensionMetadata(extensionMetadataKeys, theEventWriter);
+
 				theEventWriter.endObject(); // end meta
 			}
 		}
@@ -705,6 +708,41 @@ public class JsonParser extends BaseParser implements IJsonLikeParser {
 		theEventWriter.endObject();
 	}
 
+	private void addExtensionMetadata(List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> extensionMetadataKeys, JsonLikeWriter theEventWriter) throws IOException {
+		if (extensionMetadataKeys.isEmpty()) {
+			return;
+		}
+
+		List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> extensionKeys = new ArrayList<>(extensionMetadataKeys.size());
+		List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> modifierExtensionKeys = new ArrayList<>(extensionKeys.size());
+		for (Map.Entry<ResourceMetadataKeyEnum<?>, Object> entry : extensionMetadataKeys) {
+			if (!((ExtensionDt) entry.getValue()).isModifier()) {
+				extensionKeys.add(entry);
+			} else {
+				modifierExtensionKeys.add(entry);
+			}
+		}
+
+		writeMetadataExtensions(extensionKeys, "extension", theEventWriter);
+		writeMetadataExtensions(extensionKeys, "modifierExtension", theEventWriter);
+	}
+
+	private void writeMetadataExtensions(List<Map.Entry<ResourceMetadataKeyEnum<?>, Object>> extensions, String arrayName, JsonLikeWriter theEventWriter) throws IOException {
+		if (extensions.isEmpty()) {
+			return;
+		}
+		beginArray(theEventWriter, arrayName);
+		for (Map.Entry<ResourceMetadataKeyEnum<?>, Object> key : extensions) {
+			ExtensionDt extension = (ExtensionDt) key.getValue();
+			theEventWriter.beginObject();
+			writeOptionalTagWithTextNode(theEventWriter, "url", extension.getUrl());
+			String extensionDatatype = myContext.getRuntimeChildUndeclaredExtensionDefinition().getChildNameByDatatype(extension.getValue().getClass());
+			writeOptionalTagWithTextNode(theEventWriter, extensionDatatype, extension.getValueAsPrimitive());
+			theEventWriter.endObject();
+		}
+		theEventWriter.endArray();
+	}
+
 	/**
 	 * This is useful only for the two cases where extensions are encoded as direct children (e.g. not in some object
 	 * called _name): resource extensions, and extension extensions

hapi-fhir-base/src/main/java/ca/uhn/fhir/parser/ParserState.java

@@ -841,6 +841,25 @@ class ParserState<T> {
 			}
 		}
 
+		@Override
+		public void enteringNewElementExtension(StartElement theElem, String theUrlAttr, boolean theIsModifier, final String baseServerUrl) {
+			ResourceMetadataKeyEnum.ExtensionResourceMetadataKey resourceMetadataKeyEnum = new ResourceMetadataKeyEnum.ExtensionResourceMetadataKey(theUrlAttr);
+			Object metadataValue = myMap.get(resourceMetadataKeyEnum);
+			ExtensionDt newExtension;
+			if (metadataValue == null) {
+				newExtension = new ExtensionDt(theIsModifier);
+			} else if (metadataValue instanceof ExtensionDt) {
+				newExtension = (ExtensionDt) metadataValue;
+			} else {
+				throw new IllegalStateException("Expected ExtensionDt as custom resource metadata type, got: " + metadataValue.getClass().getSimpleName());
+			}
+			newExtension.setUrl(theUrlAttr);
+			myMap.put(resourceMetadataKeyEnum, newExtension);
+
+			ExtensionState newState = new ExtensionState(getPreResourceState(), newExtension);
+			push(newState);
+		}
+
 	}
 
 	private class MetaVersionElementState extends BaseState {

hapi-fhir-structures-dstu2/src/test/java/ca/uhn/fhir/parser/JsonParserDstu2Test.java

@@ -1,9 +1,11 @@
 package ca.uhn.fhir.parser;
 
+import static org.hamcrest.CoreMatchers.equalTo;
 import static org.hamcrest.Matchers.contains;
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.not;
 import static org.hamcrest.Matchers.stringContainsInOrder;
+import static org.hamcrest.core.IsInstanceOf.instanceOf;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertNotNull;
@@ -1688,19 +1690,65 @@ public class JsonParserDstu2Test {
 		Patient p = parser.parseResource(Patient.class, input);
 
 		ArgumentCaptor<String> capt = ArgumentCaptor.forClass(String.class);
-		verify(peh, times(4)).unknownElement(Mockito.isNull(IParseLocation.class), capt.capture());
+		verify(peh, Mockito.never()).unknownElement(Mockito.isNull(IParseLocation.class), capt.capture());
-
-		//@formatter:off
-		List<String> strings = capt.getAllValues();
-		assertThat(strings, contains(
-			"extension",
-			"extension",
-			"modifierExtension",
-			"modifierExtension"
-		));
-		//@formatter:off
-		
 		assertEquals("Smith", p.getName().get(0).getGiven().get(0).getValue());
+		assertExtensionMetadata(p, "fhir-request-method", false, StringDt.class, "POST");
+		assertExtensionMetadata(p, "fhir-request-uri", false, UriDt.class, "Patient");
+		assertExtensionMetadata(p, "modified-fhir-request-method", true, StringDt.class, "POST");
+		assertExtensionMetadata(p, "modified-fhir-request-uri", true, UriDt.class, "Patient");
+	}
+
+	private void assertExtensionMetadata(
+		BaseResource resource,
+		String url,
+		boolean isModifier,
+		Class<?> expectedType,
+		String expectedValue) {
+		ExtensionDt extension = (ExtensionDt) resource.getResourceMetadata().get(new ResourceMetadataKeyEnum.ExtensionResourceMetadataKey(url));
+		assertThat(extension.getValue(), instanceOf(expectedType));
+		assertThat(extension.isModifier(), equalTo(isModifier));
+		assertThat(extension.getValueAsPrimitive().getValueAsString(), equalTo(expectedValue));
+	}
+
+	@Test
+	public void testEncodeResourceWithExtensionMetadata() throws Exception {
+		ProcedureRequest procedureRequest = new ProcedureRequest();
+		procedureRequest.setStatus(ProcedureRequestStatusEnum.ACCEPTED);
+		addExtensionResourceMetadataKeyToResource(procedureRequest, false, "http://someurl.com", "SomeValue");
+		addExtensionResourceMetadataKeyToResource(procedureRequest, false, "http://someurl2.com", "SomeValue2");
+		addExtensionResourceMetadataKeyToResource(procedureRequest, true, "http://someurl.com/modifier", "SomeValue");
+		addExtensionResourceMetadataKeyToResource(procedureRequest, true, "http://someurl.com/modifier2", "SomeValue2");
+
+		String json = ourCtx.newJsonParser().setPrettyPrint(true).encodeResourceToString(procedureRequest);
+
+		// @formatter:off
+		assertThat(json, stringContainsInOrder("\"meta\": {",
+			"\"extension\": [", "{",
+			"\"url\": \"http://someurl.com\",",
+			"\"valueString\": \"SomeValue\"",
+			"},",
+			"{",
+			"\"url\": \"http://someurl2.com\",",
+			"\"valueString\": \"SomeValue2\"",
+			"}",
+			"],",
+			"\"modifierExtension\": [",
+			"{",
+			"\"url\": \"http://someurl.com\",",
+			"\"valueString\": \"SomeValue\"",
+			"},",
+			"{",
+			"\"url\": \"http://someurl2.com\",",
+			"\"valueString\": \"SomeValue2\"",
+			"}",
+			"]"));
+		// @formatter:on
+	}
+
+	private void addExtensionResourceMetadataKeyToResource(BaseResource resource, boolean isModifier, String url, String value) {
+		ExtensionDt extensionDt = new ExtensionDt(isModifier, url, new StringDt(value));
+		resource.getResourceMetadata()
+			.put(new ResourceMetadataKeyEnum.ExtensionResourceMetadataKey(extensionDt.getUrl()), extensionDt);
 	}
 
 	@Test

hapi-fhir-structures-dstu2/src/test/resources/patient1.json

@@ -13,11 +13,11 @@
     ],
     "modifierExtension": [
       {
-        "url": "fhir-request-method",
+        "url": "modified-fhir-request-method",
         "valueString": "POST"
       },
       {
-        "url": "fhir-request-uri",
+        "url": "modified-fhir-request-uri",
         "valueUri": "Patient"
       }
     ],