Set output_encoding in FreeMarkerView implementations

According to the official FreeMarker documentation, Spring's FreeMarkerView implementations should be configuring the output_encoding for template rendering. To address that, this commit modifies the FreeMarkerView implementations in Web MVC and WebFlux to explicitly set the output_encoding for template rendering. See https://freemarker.apache.org/docs/pgui_misc_charset.html#autoid_53 See gh-33071 Closes gh-33106
spring-projects · Jun 27, 2024 · 8b95697 · 8b95697
1 parent 95887c8
commit 8b95697
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Showing 7 changed files with 71 additions and 27 deletions.
diff --git a/...src/main/java/org/springframework/web/reactive/result/view/freemarker/FreeMarkerView.java b/...src/main/java/org/springframework/web/reactive/result/view/freemarker/FreeMarkerView.java
@@ -26,6 +26,7 @@
 import java.util.Map;
 import java.util.Optional;
 
+import freemarker.core.Environment;
 import freemarker.core.ParseException;
 import freemarker.template.Configuration;
 import freemarker.template.DefaultObjectWrapperBuilder;
@@ -333,7 +334,9 @@ protected Mono<Void> renderInternal(Map<String, Object> renderAttributes,
 									FastByteArrayOutputStream bos = new FastByteArrayOutputStream();
 									Charset charset = getCharset(contentType);
 									Writer writer = new OutputStreamWriter(bos, charset);
-									template.process(freeMarkerModel, writer);
+									Environment env = template.createProcessingEnvironment(freeMarkerModel, writer);
+									env.setOutputEncoding(charset.name());
+									env.process();
 									byte[] bytes = bos.toByteArrayUnsafe();
 									DataBuffer buffer = exchange.getResponse().bufferFactory().wrap(bytes);
 									return Mono.just(buffer);

diff --git a/...t/java/org/springframework/web/reactive/config/WebFluxViewResolutionIntegrationTests.java b/...t/java/org/springframework/web/reactive/config/WebFluxViewResolutionIntegrationTests.java
@@ -58,12 +58,20 @@ class WebFluxViewResolutionIntegrationTests {
 
 	private static final MediaType TEXT_HTML_ISO_8859_1 = MediaType.parseMediaType("text/html;charset=ISO-8859-1");
 
-	private static final String EXPECTED_BODY = "<html><body>Hello, Java Café</body></html>";
 
 
 	@Nested
 	class FreeMarkerTests {
 
+		private static final String EXPECTED_BODY = """
+			<html>
+			<body>
+			<h1>Hello, Java Café</h1>
+			<p>output_encoding: %s</p>
+			</body>
+			</html>
+			""";
+
 		private static final ClassTemplateLoader classTemplateLoader =
 				new ClassTemplateLoader(WebFluxViewResolutionIntegrationTests.class, "");
 
@@ -77,21 +85,21 @@ void freemarkerWithInvalidConfig() {
 		@Test
 		void freemarkerWithDefaults() throws Exception {
 			MockServerHttpResponse response = runTest(FreeMarkerWebFluxConfig.class);
-			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY).expectComplete().verify();
+			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY.formatted("UTF-8")).expectComplete().verify();
 			assertThat(response.getHeaders().getContentType()).isEqualTo(TEXT_HTML_UTF8);
 		}
 
 		@Test
 		void freemarkerWithExplicitDefaultEncoding() throws Exception {
 			MockServerHttpResponse response = runTest(ExplicitDefaultEncodingConfig.class);
-			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY).expectComplete().verify();
+			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY.formatted("UTF-8")).expectComplete().verify();
 			assertThat(response.getHeaders().getContentType()).isEqualTo(TEXT_HTML_UTF8);
 		}
 
 		@Test
 		void freemarkerWithExplicitDefaultEncodingAndContentType() throws Exception {
 			MockServerHttpResponse response = runTest(ExplicitDefaultEncodingAndContentTypeConfig.class);
-			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY).expectComplete().verify();
+			StepVerifier.create(response.getBodyAsString()).expectNext(EXPECTED_BODY.formatted("ISO-8859-1")).expectComplete().verify();
 			// When the Content-Type (supported media type) is explicitly set on the view resolver, it should be used.
 			assertThat(response.getHeaders().getContentType()).isEqualTo(TEXT_HTML_ISO_8859_1);
 		}

diff --git a/...g-webflux/src/test/resources/org/springframework/web/reactive/config/index_ISO-8859-1.ftl b/...g-webflux/src/test/resources/org/springframework/web/reactive/config/index_ISO-8859-1.ftl
@@ -1 +1,6 @@
-<html><body>${hello}, Java Café</body></html>
+<html>
+<body>
+<h1>${hello}, Java Café</h1>
+<p>output_encoding: ${.output_encoding}</p>
+</body>
+</html>
diff --git a/spring-webflux/src/test/resources/org/springframework/web/reactive/config/index_UTF-8.ftl b/spring-webflux/src/test/resources/org/springframework/web/reactive/config/index_UTF-8.ftl
@@ -1 +1,6 @@
-<html><body>${hello}, Java Café</body></html>
+<html>
+<body>
+<h1>${hello}, Java Café</h1>
+<p>output_encoding: ${.output_encoding}</p>
+</body>
+</html>
diff --git a/...-webmvc/src/main/java/org/springframework/web/servlet/view/freemarker/FreeMarkerView.java b/...-webmvc/src/main/java/org/springframework/web/servlet/view/freemarker/FreeMarkerView.java
@@ -22,6 +22,7 @@
 import java.util.Locale;
 import java.util.Map;
 
+import freemarker.core.Environment;
 import freemarker.core.ParseException;
 import freemarker.template.Configuration;
 import freemarker.template.DefaultObjectWrapperBuilder;
@@ -364,19 +365,26 @@ protected Template getTemplate(String name, Locale locale) throws IOException {
 	}
 
 	/**
-	 * Process the FreeMarker template to the servlet response.
+	 * Process the FreeMarker template and write the result to the response.
+	 * <p>As of Spring Framework 6.2, this method sets the
+	 * {@linkplain Environment#setOutputEncoding(String) output encoding} of the
+	 * FreeMarker {@link Environment} to the character encoding of the supplied
+	 * {@link HttpServletResponse}.
 	 * <p>Can be overridden to customize the behavior.
 	 * @param template the template to process
 	 * @param model the model for the template
 	 * @param response servlet response (use this to get the OutputStream or Writer)
 	 * @throws IOException if the template file could not be retrieved
 	 * @throws TemplateException if thrown by FreeMarker
-	 * @see freemarker.template.Template#process(Object, java.io.Writer)
+	 * @see freemarker.template.Template#createProcessingEnvironment(Object, java.io.Writer)
+	 * @see freemarker.core.Environment#process()
 	 */
 	protected void processTemplate(Template template, SimpleHash model, HttpServletResponse response)
 			throws IOException, TemplateException {
 
-		template.process(model, response.getWriter());
+		Environment env = template.createProcessingEnvironment(model, response.getWriter());
+		env.setOutputEncoding(response.getCharacterEncoding());
+		env.process();
 	}
 
 

diff --git a/...ava/org/springframework/web/servlet/config/annotation/ViewResolutionIntegrationTests.java b/...ava/org/springframework/web/servlet/config/annotation/ViewResolutionIntegrationTests.java
@@ -48,9 +48,6 @@
  */
 class ViewResolutionIntegrationTests {
 
-	private static final String EXPECTED_BODY = "<html><body>Hello, Java Café</body></html>";
-
-
 	@BeforeAll
 	static void verifyDefaultFileEncoding() {
 		assertThat(System.getProperty("file.encoding")).as("JVM default file encoding").isEqualTo("UTF-8");
@@ -60,6 +57,15 @@ static void verifyDefaultFileEncoding() {
 	@Nested
 	class FreeMarkerTests {
 
+		private static final String EXPECTED_BODY = """
+				<html>
+				<body>
+				<h1>Hello, Java Café</h1>
+				<p>output_encoding: %s</p>
+				</body>
+				</html>
+				""";
+
 		@Test
 		void freemarkerWithInvalidConfig() {
 			assertThatRuntimeException()
@@ -69,45 +75,49 @@ void freemarkerWithInvalidConfig() {
 
 		@Test
 		void freemarkerWithDefaults() throws Exception {
+			String encoding = "ISO-8859-1";
 			MockHttpServletResponse response = runTest(FreeMarkerWebConfig.class);
 			assertThat(response.isCharset()).as("character encoding set in response").isTrue();
-			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY);
+			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY.formatted(encoding));
 			// Prior to Spring Framework 6.2, the charset is not updated in the Content-Type.
 			// Thus, we expect ISO-8859-1 instead of UTF-8.
-			assertThat(response.getCharacterEncoding()).isEqualTo("ISO-8859-1");
-			assertThat(response.getContentType()).isEqualTo("text/html;charset=ISO-8859-1");
+			assertThat(response.getCharacterEncoding()).isEqualTo(encoding);
+			assertThat(response.getContentType()).isEqualTo("text/html;charset=" + encoding);
 		}
 
 		@Test  // gh-16629, gh-33071
 		void freemarkerWithExistingViewResolver() throws Exception {
+			String encoding = "ISO-8859-1";
 			MockHttpServletResponse response = runTest(ExistingViewResolverConfig.class);
 			assertThat(response.isCharset()).as("character encoding set in response").isTrue();
-			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY);
+			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY.formatted(encoding));
 			// Prior to Spring Framework 6.2, the charset is not updated in the Content-Type.
 			// Thus, we expect ISO-8859-1 instead of UTF-8.
-			assertThat(response.getCharacterEncoding()).isEqualTo("ISO-8859-1");
-			assertThat(response.getContentType()).isEqualTo("text/html;charset=ISO-8859-1");
+			assertThat(response.getCharacterEncoding()).isEqualTo(encoding);
+			assertThat(response.getContentType()).isEqualTo("text/html;charset=" + encoding);
 		}
 
 		@Test  // gh-33071
 		void freemarkerWithExplicitDefaultEncoding() throws Exception {
+			String encoding = "ISO-8859-1";
 			MockHttpServletResponse response = runTest(ExplicitDefaultEncodingConfig.class);
 			assertThat(response.isCharset()).as("character encoding set in response").isTrue();
-			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY);
+			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY.formatted(encoding));
 			// Prior to Spring Framework 6.2, the charset is not updated in the Content-Type.
 			// Thus, we expect ISO-8859-1 instead of UTF-8.
-			assertThat(response.getCharacterEncoding()).isEqualTo("ISO-8859-1");
-			assertThat(response.getContentType()).isEqualTo("text/html;charset=ISO-8859-1");
+			assertThat(response.getCharacterEncoding()).isEqualTo(encoding);
+			assertThat(response.getContentType()).isEqualTo("text/html;charset=" + encoding);
 		}
 
 		@Test  // gh-33071
 		void freemarkerWithExplicitDefaultEncodingAndContentType() throws Exception {
+			String encoding = "UTF-16";
 			MockHttpServletResponse response = runTest(ExplicitDefaultEncodingAndContentTypeConfig.class);
 			assertThat(response.isCharset()).as("character encoding set in response").isTrue();
-			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY);
+			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY.formatted(encoding));
 			// When the Content-Type is explicitly set on the view resolver, it should be used.
-			assertThat(response.getCharacterEncoding()).isEqualTo("UTF-16");
-			assertThat(response.getContentType()).isEqualTo("text/html;charset=UTF-16");
+			assertThat(response.getCharacterEncoding()).isEqualTo(encoding);
+			assertThat(response.getContentType()).isEqualTo("text/html;charset=" + encoding);
 		}
 
 
@@ -202,7 +212,7 @@ void groovyMarkupInvalidConfig() {
 		@Test
 		void groovyMarkup() throws Exception {
 			MockHttpServletResponse response = runTest(GroovyMarkupWebConfig.class);
-			assertThat(response.getContentAsString()).isEqualTo(EXPECTED_BODY);
+			assertThat(response.getContentAsString()).isEqualTo("<html><body>Hello, Java Café</body></html>");
 		}
 
 

diff --git a/...vc/src/test/resources/org/springframework/web/servlet/config/annotation/WEB-INF/index.ftl b/...vc/src/test/resources/org/springframework/web/servlet/config/annotation/WEB-INF/index.ftl
@@ -1 +1,6 @@
-<html><body>${hello}, Java Café</body></html>
+<html>
+<body>
+<h1>${hello}, Java Café</h1>
+<p>output_encoding: ${.output_encoding}</p>
+</body>
+</html>