Swagger spitting out xml response instead of json - spring

Question

I'm a week old in spring. I'm developing a pure RESTful API service using Spring + maven + Jackson. While exploring some best practices, I came across this, so I decided I'll be using swagger with spring mvc (and swaggerUI) for documentation. I went through this and this tutorial for doing what I wanted. Everything was going fine and dandy until I realized after hitting /api-docs I got XML response, as opposed to JSON response in tutorials and every-other-where. This won't work fine when I add SwaggerUI. Later I found out here that swaggerUI expects json. I could always go back and use swagger without server integration (https://github.com/wordnik/swagger-core/wiki/Adding-Swagger-to-your-API), but that won't really satisfy my needs.
Here are the contents of pom.xml:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.darshandzend</groupId>
<artifactId>swjs</artifactId>
<name>swjs</name>
<packaging>war</packaging>
<version>1.0.0-BUILD-SNAPSHOT</version>
<properties>
<java-version>1.6</java-version>
<org.springframework-version>3.1.1.RELEASE</org.springframework-version>
<org.aspectj-version>1.6.10</org.aspectj-version>
<org.slf4j-version>1.6.6</org.slf4j-version>
</properties>
<dependencies>
<!-- Spring -->
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${org.springframework-version}</version>
<exclusions>
<!-- Exclude Commons Logging in favor of SLF4j -->
<exclusion>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
</exclusion>
</exclusions>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>${org.springframework-version}</version>
</dependency>
<!-- AspectJ -->
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjrt</artifactId>
<version>${org.aspectj-version}</version>
</dependency>
<!-- Logging -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>${org.slf4j-version}</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>${org.slf4j-version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>${org.slf4j-version}</version>
<scope>runtime</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.15</version>
<exclusions>
<exclusion>
<groupId>javax.mail</groupId>
<artifactId>mail</artifactId>
</exclusion>
<exclusion>
<groupId>javax.jms</groupId>
<artifactId>jms</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jdmk</groupId>
<artifactId>jmxtools</artifactId>
</exclusion>
<exclusion>
<groupId>com.sun.jmx</groupId>
<artifactId>jmxri</artifactId>
</exclusion>
</exclusions>
<scope>runtime</scope>
</dependency>
<!-- #Inject -->
<dependency>
<groupId>javax.inject</groupId>
<artifactId>javax.inject</artifactId>
<version>1</version>
</dependency>
<!-- Servlet -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<!-- Test -->
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.7</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>org.codehaus.jackson</groupId>
<artifactId>jackson-mapper-asl</artifactId>
<version>1.9.13</version>
</dependency>
<dependency>
<groupId>com.wordnik</groupId>
<artifactId>swagger-core</artifactId>
<version>1.1-SNAPSHOT.121130</version>
</dependency>
<dependency>
<groupId>com.mangofactory</groupId>
<artifactId>swagger-springmvc</artifactId>
<version>0.6.3</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<artifactId>maven-eclipse-plugin</artifactId>
<version>2.9</version>
<configuration>
<additionalProjectnatures>
<projectnature>org.springframework.ide.eclipse.core.springnature</projectnature>
</additionalProjectnatures>
<additionalBuildcommands>
<buildcommand>org.springframework.ide.eclipse.core.springbuilder</buildcommand>
</additionalBuildcommands>
<downloadSources>true</downloadSources>
<downloadJavadocs>true</downloadJavadocs>
</configuration>
</plugin>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.5.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
<compilerArgument>-Xlint:all</compilerArgument>
<showWarnings>true</showWarnings>
<showDeprecation>true</showDeprecation>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.2.1</version>
<configuration>
<mainClass>org.test.int1.Main</mainClass>
</configuration>
</plugin>
</plugins>
</build>
servlet context:
<?xml version="1.0" encoding="UTF-8"?>
<beans:beans xmlns="http://www.springframework.org/schema/mvc"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:beans="http://www.springframework.org/schema/beans"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
<!-- DispatcherServlet Context: defines this servlet's request-processing
infrastructure -->
<!-- Enables the Spring MVC #Controller programming model -->
<annotation-driven />
<!-- Handles HTTP GET requests for /resources/** by efficiently serving
up static resources in the ${webappRoot}/resources directory -->
<resources mapping="/resources/**" location="/resources/" />
<!-- Resolves views selected for rendering by #Controllers to .jsp resources
in the /WEB-INF/views directory -->
<beans:bean
class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<beans:property name="prefix" value="/WEB-INF/views/" />
<beans:property name="suffix" value=".jsp" />
</beans:bean>
<context:component-scan base-package="com.darshandzend.swjs" />
<beans:bean class="com.mangofactory.swagger.configuration.DocumentationConfig" />
<context:property-placeholder location="classpath:/swagger.properties" />
swagger.properties
documentation.services.version=1.0
documentation.services.basePath=http://localhost:8080/swjs/
I tried GET /api-docs/ in chrome dev http tool with "Accept" header set to "application/json", which worked. Does this mean I manually have to set request headers somewhre? I'm adding web.xml just in case.
web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<!-- The definition of the Root Spring Container shared by all Servlets and Filters -->
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/root-context.xml</param-value>
</context-param>
<!-- Creates the Spring Container shared by all Servlets and Filters -->
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<!-- Processes application requests -->
<servlet>
<servlet-name>appServlet</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring/appServlet/servlet-context.xml</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>appServlet</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
I reckon swagger won't require any special annotations so my java codebase remains the same.
Is this question too long? Pardon me, for I'm new to SO. Please edit and suggest.
Controller class:
#Api(value = "contacts", description = "contacts") // Swagger annotation
#Controller
#RequestMapping("/home")
public class HomeController {
#ResponseBody
#RequestMapping(method=RequestMethod.GET)
public Response select() {
return new Response("success", "", "this is the humble abode of everything");
}
#ResponseBody
#RequestMapping(value="/{id}",method=RequestMethod.GET)
public Response get(#PathVariable String id) {
return new Response("Success", "", id);
}
}

Answer 1

Swagger-ui does not set an Accept header with its AJAX requests. Unfortunately swagger-springmvc returns XML if no accept header or no path extension (.json) is given.
You can manually add a JSON accept header to every request swagger-ui executes. Simply add the following JavaScript line to your swagger-ui index.html file:
window.authorizations.add("Accept",
new ApiKeyAuthorization("Accept", "application/json", "header"));
This is my modified index.html file:
<!DOCTYPE html>
<html>
<head>
<title>Swagger UI</title>
<link href='//fonts.googleapis.com/css?family=Droid+Sans:400,700' rel='stylesheet' type='text/css'/>
<link href='css/highlight.default.css' media='screen' rel='stylesheet' type='text/css'/>
<link href='css/screen.css' media='screen' rel='stylesheet' type='text/css'/>
<script type="text/javascript" src="lib/shred.bundle.js"></script>
<script src='lib/jquery-1.8.0.min.js' type='text/javascript'></script>
<script src='lib/jquery.slideto.min.js' type='text/javascript'></script>
<script src='lib/jquery.wiggle.min.js' type='text/javascript'></script>
<script src='lib/jquery.ba-bbq.min.js' type='text/javascript'></script>
<script src='lib/handlebars-1.0.0.js' type='text/javascript'></script>
<script src='lib/underscore-min.js' type='text/javascript'></script>
<script src='lib/backbone-min.js' type='text/javascript'></script>
<script src='lib/swagger.js' type='text/javascript'></script>
<script src='swagger-ui.js' type='text/javascript'></script>
<script src='lib/highlight.7.3.pack.js' type='text/javascript'></script>
<script type="text/javascript">
$(function () {
window.swaggerUi = new SwaggerUi({
url: "http://localhost:8080/api-docs",
dom_id: "swagger-ui-container",
supportedSubmitMethods: ['get', 'post', 'put', 'delete'],
onComplete: function(swaggerApi, swaggerUi){
if(console) {
console.log("Loaded SwaggerUI")
}
$('pre code').each(function(i, e) {hljs.highlightBlock(e)});
},
onFailure: function(data) {
if(console) {
console.log("Unable to Load SwaggerUI");
console.log(data);
}
},
docExpansion: "none"
});
window.authorizations.add("Accept", new ApiKeyAuthorization("Accept", "application/json", "header"));
$('#input_apiKey').change(function() {
var key = $('#input_apiKey')[0].value;
console.log("key: " + key);
if(key && key.trim() != "") {
console.log("added key " + key);
window.authorizations.add("key", new ApiKeyAuthorization("api_key", key, "query"));
}
})
window.swaggerUi.load();
});
</script>
</head>
<body>
<div id='header'>
<div class="swagger-ui-wrap">
<a id="logo" href="http://swagger.wordnik.com">swagger</a>
<form id='api_selector'>
<div class='input icon-btn'>
<img id="show-pet-store-icon" src="images/pet_store_api.png" title="Show Swagger Petstore Example Apis">
</div>
<div class='input icon-btn'>
<img id="show-wordnik-dev-icon" src="images/wordnik_api.png" title="Show Wordnik Developer Apis">
</div>
<div class='input'><input placeholder="http://example.com/api" id="input_baseUrl" name="baseUrl" type="text"/></div>
<div class='input'><input placeholder="api_key" id="input_apiKey" name="apiKey" type="text"/></div>
<div class='input'><a id="explore" href="#">Explore</a></div>
</form>
</div>
</div>
<div id="message-bar" class="swagger-ui-wrap">
</div>
<div id="swagger-ui-container" class="swagger-ui-wrap">
</div>
</body>
</html>