class ApiTokenFilter extends GenericFilterBean.groovy

package com.mycompany

import org.springframework.security.core.context.SecurityContextHolder
import org.springframework.security.*
import org.springframework.web.filter.GenericFilterBean;
import org.springframework.beans.factory.*
import org.springframework.context.*
import javax.servlet.*
import javax.servlet.http.*

class ApiTokenFilter extends GenericFilterBean {

  ///////////////////////////// Class Attributes \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
  
  ////////////////////////////// Class Methods \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
  
  //////////////////////////////// Attributes \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\

  def authenticationManager
  
  def apiProvider
  
  /////////////////////////////// Constructors \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\  
  
  ////////////////////////////////// Methods \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
  
  //------------------------ Implements:
  
  //------------------------ Overrides: GenericFilterBean

  public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) {

    if (SecurityContextHolder.getContext().getAuthentication() == null) {
      def userId = request.getParameter("userId")
      def apiKey = request.getParameter("apiKey")
      if ( userId && apiKey ) {

        def myAuth = new ApiTokenAuthentication(
            name: userId,
            credentials: apiKey,
            principal: userId,
            authenticated: true
        )
        
        myAuth = apiProvider.authenticate(myAuth)      
        if (myAuth) {
          // Store to SecurityContextHolder
          SecurityContextHolder.getContext().setAuthentication(myAuth);
         }
      }
    }
    chain.doFilter(request, response)
  }
  
  //---------------------------- Abstract Methods -----------------------------
  
  //---------------------------- Utility Methods ------------------------------
  
  //---------------------------- Property Methods -----------------------------       
 
}