I'd like to ask. How to modify http request before handling in the Spring REST (MVC) controller?
As far as I found I can make with servlets through filter and custom request wrapper. So does anyone know how to make it in Spring (e.g. via interceptors)?
My aim is to add new request parameter to request to use it into controller
Thx in advance
You can use Filter to modify httprequestparameter value. Watchout the implementation:
Web.xml
<filter>
<description>check request for service token</description>
<filter-name>CustomFilter</filter-name>
<filter-class>com.filters.CustomFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>CustomFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
Create a Filter Class:
public class CustomFilter implements Filter {
String encoding;
public void init(FilterConfig config) throws ServletException {
encoding = config.getInitParameter("requestEncoding");
if (encoding == null) {
encoding = "UTF-8";
}
}
public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain)
throws ServletException, IOException {
// next handler
System.out.println("accessed");
filterChain.doFilter(new CustomFilterWrapper((HttpServletRequest)request),(HttpServletResponse)response);
}
public void destroy() {
}
}
Create a CustomFilterWrapper where you override getParameter method to modify certain request parameter. In my case I change value if the request param is maverick.
public class CustomFilterWrapper extends HttpServletRequestWrapper {
public CustomFilterWrapper(HttpServletRequest request) {
super(request);
}
@Override
public String getParameter(String name) {
String[] vals = getParameterMap().get(name);
if (name.equalsIgnoreCase("maverick")) {
return "modify value";
} else if (vals != null && vals.length > 0) {
return vals[0];
} else {
return null;
}
}
}
