send etag for images

baloise · Jan 24, 2024 · 1a1ae4a · 1a1ae4a
1 parent f1293f4
commit 1a1ae4a
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Showing 2 changed files with 38 additions and 5 deletions.
diff --git a/src/main/java/com/baloise/azure/FunctionalOrgEndpoint.java b/src/main/java/com/baloise/azure/FunctionalOrgEndpoint.java
@@ -7,6 +7,7 @@
 
 import java.io.IOException;
 import java.text.ParseException;
+import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
@@ -25,6 +26,7 @@
 import com.microsoft.azure.functions.HttpMethod;
 import com.microsoft.azure.functions.HttpRequestMessage;
 import com.microsoft.azure.functions.HttpResponseMessage;
+import com.microsoft.azure.functions.HttpResponseMessage.Builder;
 import com.microsoft.azure.functions.HttpStatus;
 import com.microsoft.azure.functions.annotation.AuthorizationLevel;
 import com.microsoft.azure.functions.annotation.BindingName;
@@ -104,9 +106,31 @@ public HttpResponseMessage v1(
 	}
 
 	private HttpResponseMessage createAvatarResponse(HttpRequestMessage<Optional<String>> request, String id) throws IOException {
-		return request.createResponseBuilder(HttpStatus.OK)
+		byte[] avatar = graph().avatar(id);
+		String myETag = String.valueOf(Arrays.hashCode(avatar));		
+		String theirETag = ignoreKeyCase(request.getHeaders()).get("If-None-Match");
+		boolean sameEtag = Objects.equals(myETag, theirETag);
+		Builder response = request
+				.createResponseBuilder(sameEtag? HttpStatus.NOT_MODIFIED : HttpStatus.OK)
 				.header("Content-Type","image/jpeg")
-				.body(graph().avatar(id)).build();
+				.header("ETag",myETag);
+		if(!sameEtag) {
+			response = response
+					.header("Content-Length",String.valueOf(avatar.length))
+					.body(avatar);
+		}
+		return response.build();
+	}
+
+	private Map<String, String> ignoreKeyCase(Map<String, String> mixedMap) {
+		Map<String, String> lowMap = new HashMap<>() {
+			@Override
+			public String get(Object key) {
+				return super.get(key.toString().toLowerCase());
+			}
+		};
+		mixedMap.entrySet().stream().forEach(e->lowMap.put(e.getKey().toLowerCase(), e.getValue()));
+		return lowMap;
 	}
 
 	private HttpResponseMessage createRootResponse(HttpRequestMessage<Optional<String>> request, ExecutionContext context)

diff --git a/src/test/java/com/baloise/azure/DevServer.java b/src/test/java/com/baloise/azure/DevServer.java
@@ -290,9 +290,13 @@ public void start() throws IOException {
 				Method method = functionMapping.get(path.peek());
 				ResponseBuilderImpl.HttpResponseMessageImpl resp = (ResponseBuilderImpl.HttpResponseMessageImpl) method.invoke(getInstance(method), parameterMappings.get(method).map(path, exg));
 				resp.getHeaders().forEach((k,v)-> exg.getResponseHeaders().add(k,v));
-				byte response[] = getResponseBytes(resp);
-				exg.sendResponseHeaders(resp.getStatusCode(), response.length);
-				out.write(response);
+				if(hasBody(resp)) {
+					byte response[] = getResponseBytes(resp);
+					exg.sendResponseHeaders(resp.getStatusCode(), response.length);
+					out.write(response);
+				} else {
+					exg.sendResponseHeaders(resp.getStatusCode(), -1);
+				}
 			} catch (Throwable t) {
 				logger.log(Level.WARNING, t.getLocalizedMessage(), t);
 			}
@@ -301,8 +305,13 @@ public void start() throws IOException {
 		server.start();
 	}
 
+	private boolean hasBody(com.baloise.azure.DevServer.ResponseBuilderImpl.HttpResponseMessageImpl resp) {
+		return resp.getBody()!= null;
+	}
+
 	private byte[] getResponseBytes(com.baloise.azure.DevServer.ResponseBuilderImpl.HttpResponseMessageImpl resp) throws UnsupportedEncodingException {
 		Object body = resp.getBody();
+		if(body == null) return new byte[0];
 		if(body instanceof byte[]) {
 			return (byte[]) body;
 		}