feat(swagger-ui): add springdoc.swagger-ui.document-title property

springdoc-openapi-starter-common/src/main/java/org/springdoc/core/properties/AbstractSwaggerUiConfigProperties.java

@@ -185,6 +185,29 @@ public abstract class AbstractSwaggerUiConfigProperties {
 	 */
 	protected Boolean withCredentials;
 
+	/**
+	 * The Document title.
+	 */
+	protected String documentTitle;
+
+	/**
+	 * Gets document title.
+	 *
+	 * @return the document title
+	 */
+	public String getDocumentTitle() {
+		return documentTitle;
+	}
+
+	/**
+	 * Sets document title.
+	 *
+	 * @param documentTitle the document title
+	 */
+	public void setDocumentTitle(String documentTitle) {
+		this.documentTitle = documentTitle;
+	}
+
 	/**
 	 * Gets with credentials.
 	 *

springdoc-openapi-starter-common/src/main/java/org/springdoc/ui/AbstractSwaggerIndexTransformer.java

@@ -59,6 +59,11 @@ public class AbstractSwaggerIndexTransformer {
 	 */
 	private static final String PRESETS = "presets: [";
 
+	/**
+	 * The constant EDITOR_FOLD_MARKER.
+	 */
+	private static final String EDITOR_FOLD_MARKER = "//</editor-fold>";
+
 	/**
 	 * The Swagger ui o auth properties.
 	 */
@@ -178,6 +183,9 @@ else if (swaggerUiConfig.getCsrf().isUseSessionStorage())
 			html = setConfiguredApiDocsUrl(html);
 		}
 
+		if (StringUtils.isNotEmpty(swaggerUiConfig.getDocumentTitle()))
+			html = addDocumentTitle(html);
+
 		return html;
 	}
 
@@ -325,4 +333,41 @@ protected String addSyntaxHighlight(String html) {
 		return html.replace(PRESETS, stringBuilder.toString());
 	}
 
+	/**
+	 * Add document title script.
+	 *
+	 * @param html the html
+	 * @return the string
+	 */
+	protected String addDocumentTitle(String html) {
+		if (!html.contains(EDITOR_FOLD_MARKER)) {
+			return html;
+		}
+		StringBuilder stringBuilder = new StringBuilder("document.title = '");
+		stringBuilder.append(escapeJavaScriptString(swaggerUiConfig.getDocumentTitle()));
+		stringBuilder.append("';\n\n  ");
+		stringBuilder.append(EDITOR_FOLD_MARKER);
+		return html.replace(EDITOR_FOLD_MARKER, stringBuilder.toString());
+	}
+
+	/**
+	 * Escape special characters for JavaScript string literal.
+	 *
+	 * @param input the input string
+	 * @return the escaped string
+	 */
+	private String escapeJavaScriptString(String input) {
+		if (input == null) {
+			return "";
+		}
+		return input
+				.replace("\\", "\\\\")
+				.replace("'", "\\'")
+				.replace("\n", "\\n")
+				.replace("\r", "\\r")
+				.replace("\t", "\\t")
+				.replace("<", "\\u003c")
+				.replace(">", "\\u003e");
+	}
+
 }

springdoc-openapi-starter-common/src/test/java/org/springdoc/ui/AbstractSwaggerIndexTransformerTest.java

@@ -18,6 +18,7 @@
 
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.not;
 
 @ExtendWith(MockitoExtension.class)
 class AbstractSwaggerIndexTransformerTest {
@@ -67,4 +68,63 @@ void setApiDocUrlCorrectly() throws IOException {
 		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), is);
 		assertThat(html, containsString(apiDocUrl));
 	}
+
+	@Test
+	void documentTitle_whenSet_addsDocumentTitleScript() throws IOException {
+		swaggerUiConfig.setDocumentTitle("My Custom API Documentation");
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, containsString("document.title = 'My Custom API Documentation';"));
+	}
+
+	@Test
+	void documentTitle_whenNotSet_doesNotAddScript() throws IOException {
+		swaggerUiConfig.setDocumentTitle(null);
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, not(containsString("document.title")));
+	}
+
+	@Test
+	void documentTitle_whenEmpty_doesNotAddScript() throws IOException {
+		swaggerUiConfig.setDocumentTitle("");
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, not(containsString("document.title")));
+	}
+
+	@Test
+	void documentTitle_escapesSpecialCharacters() throws IOException {
+		swaggerUiConfig.setDocumentTitle("Test's API \\ Documentation");
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, containsString("document.title = 'Test\\'s API \\\\ Documentation';"));
+	}
+
+	@Test
+	void documentTitle_escapesNewlines() throws IOException {
+		swaggerUiConfig.setDocumentTitle("Test\nAPI\rDocs\tTitle");
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, containsString("document.title = 'Test\\nAPI\\rDocs\\tTitle';"));
+	}
+
+	@Test
+	void documentTitle_escapesScriptTags() throws IOException {
+		swaggerUiConfig.setDocumentTitle("</script><script>alert('xss')</script>");
+		InputStream inputStream = new ByteArrayInputStream(swaggerInitJs.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, not(containsString("</script><script>")));
+		assertThat(html, containsString("\\u003c/script\\u003e\\u003cscript\\u003ealert"));
+	}
+
+	@Test
+	void documentTitle_whenMarkerMissing_returnsOriginalHtml() throws IOException {
+		String htmlWithoutMarker = "window.onload = function() { window.ui = SwaggerUIBundle({}); };";
+		swaggerUiConfig.setDocumentTitle("My Title");
+		swaggerUiConfig.setUrl(null);
+		InputStream inputStream = new ByteArrayInputStream(htmlWithoutMarker.getBytes(StandardCharsets.UTF_8));
+		var html = underTest.defaultTransformations(new SwaggerUiConfigParameters(swaggerUiConfig), inputStream);
+		assertThat(html, not(containsString("document.title")));
+	}
 }

springdoc-openapi-starter-webmvc-ui/src/test/java/test/org/springdoc/ui/app39/SpringDocApp39Test.java

@@ -0,0 +1,47 @@
+/*
+ *
+ *  * Copyright 2019-2020 the original author or authors.
+ *  *
+ *  * Licensed under the Apache License, Version 2.0 (the "License");
+ *  * you may not use this file except in compliance with the License.
+ *  * You may obtain a copy of the License at
+ *  *
+ *  *      https://www.apache.org/licenses/LICENSE-2.0
+ *  *
+ *  * Unless required by applicable law or agreed to in writing, software
+ *  * distributed under the License is distributed on an "AS IS" BASIS,
+ *  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *  * See the License for the specific language governing permissions and
+ *  * limitations under the License.
+ *
+ */
+
+package test.org.springdoc.ui.app39;
+
+import org.junit.jupiter.api.Test;
+import org.springdoc.core.utils.Constants;
+import test.org.springdoc.ui.AbstractSpringDocTest;
+
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.test.context.TestPropertySource;
+
+import static org.hamcrest.Matchers.containsString;
+import static org.springframework.test.web.servlet.request.MockMvcRequestBuilders.get;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.content;
+import static org.springframework.test.web.servlet.result.MockMvcResultMatchers.status;
+
+@TestPropertySource(properties = {
+		"springdoc.swagger-ui.document-title=My Custom API Documentation"
+})
+public class SpringDocApp39Test extends AbstractSpringDocTest {
+
+	@Test
+	void transformedIndexWithDocumentTitle() throws Exception {
+		mockMvc.perform(get(Constants.SWAGGER_INITIALIZER_URL))
+				.andExpect(status().isOk())
+				.andExpect(content().string(containsString("document.title = 'My Custom API Documentation';")));
+	}
+
+	@SpringBootApplication
+	static class SpringDocTestApp {}
+}