grails无法在此处发出重定向（..）。当url参数包含尖括号时，先前调用重定向（..）

Posted 2021-03-28

例外情况是：无法在此处发出重定向（..）。之前对重定向（..）的调用已经重定向了响应.Stacktrace如下：org.codehaus.groovy.grails.web.servlet.mvc.exceptions.CannotRedirectException：无法在此处发出重定向（..）。先前对重定向（..）的调用已经重定向了响应。

请求网址：http://localhost:8080/auth/index?param1= <

然后扔了

ceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: javax.servlet.ServletException: Servlet execution threw an exception
    at grails.plugin.cache.web.filter.PageFragmentCachingFilter.doFilter(PageFragmentCachingFilter.java:198)
    at grails.plugin.cache.web.filter.AbstractFilter.doFilter(AbstractFilter.java:63)
    ... 54 more
Caused by: org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.codehaus.groovy.grails.exceptions.GrailsRuntimeException: javax.servlet.ServletException: javax.servlet.ServletException: Servlet execution threw an exception
    ... 56 more

答案

如果URL包含特殊字符，则需要对URL进行编码，这些特殊字符在编程语言（如groovy）中具有特殊含义。

编码URL如下

import java.net.URLEncoder;
String url = "http://localhost:8080/auth/index?param1=<";   
String encodedUrl = URLEncoder.encode(url, "UTF-8");
println encodedUrl​ 
redirect(url: encodedUrl)

另一答案

如果使用重定向，则使用return关键字，它不是方法中的最后一个语句。

默认情况下，Grails使用最后一个语句作为return语句。如果您重定向并且它是最后一个语句，则它会自动运行。但是，如果在if语句中使用return并且return不是最后一个语句，则情况并非如此。在这些情况下，您必须显式使用return关键字。

def someAction(){
     if(someCondition == true){
          redirect action: "anotherAction"
          return                  // this prevents the execution of the code below
     }else{
        // do something else 
     } 

     redirect action: "myAction"  // this will throw an error if the condition above matched and it redirected without return keyword
}