3.0.1: add CORS filter

pom.xml

@@ -7,7 +7,7 @@
   <modelVersion>4.0.0</modelVersion>
   <groupId>org.teapot</groupId>
   <artifactId>teapot-backend</artifactId>
-  <version>3.0.0</version>
+  <version>3.0.1</version>
   <packaging>jar</packaging>
 
   <parent>

src/main/java/org/teapot/backend/config/CorsFilter.java

@@ -0,0 +1,27 @@
+package org.teapot.backend.config;
+
+import org.springframework.stereotype.Component;
+import org.springframework.web.filter.OncePerRequestFilter;
+
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+
+@Component
+public class CorsFilter extends OncePerRequestFilter {
+
+    @Override
+    protected void doFilterInternal(HttpServletRequest request, HttpServletResponse response, FilterChain filterChain)
+            throws ServletException, IOException {
+        response.setHeader("Access-Control-Allow-Origin", "*");
+        response.setHeader("Access-Control-Allow-Methods",
+                "POST, GET, PATCH, DELETE, OPTIONS");
+        response.setHeader("Access-Control-Max-Age", "3600");
+        response.setHeader("Access-Control-Allow-Headers",
+                "x-requested-with, Content-Type, Authorization, Accept");
+
+        filterChain.doFilter(request, response);
+    }
+}