I've developed a Spring API /getFileData, which accepts three URI parameters viz. businessDate/fileName/recordId. It is possible to have any of them can be passed as null. But I still want my API to be working in this case also. How can I achieve this?
I've tried using #GetMapping("getFileData/{businessDate}/{fileName}/{recordId}", "getFileData/{businessDate}//", "getFileData/{businessDate}/{fileName}/")..so on like this for all possible combinations.
#RequestMapping(value = "/getFileData/{businessDate}/{fileName}/{recordId}", method = RequestMethod.GET)
I want this API to be working for all the combination of URI parameters if something get missed out. for example someone requested,
/getFileData///22 or
/getFileData/22Dec2018/ or
/getFileData//treasure/22
You can do that with a #RequestParam of type java.util.Map.
With your design, you will have various #PathVariable params in the controller method as well as the order of path variables /{var1}/{var2}... constructs the url so I don't think it would be possible to skip a path variable in the url and still call the same controller method.
Related
I'm working in a spring boot application, where i'm getting violation as, "number of parameters should be less than 8"
i,m passing all the parameters through request param
I'm passing exactly 8 parameters all are mandatory
any other way to overcome this ?
In general, it looks like bad API design that you have so many request params. Request params are normally only used for things like filter and sorting options, but not to provide any actual data. Instead, use the request body.
Nevertheless, you can also get all parameters as a HashMap using:
#PostMapping("/api/example")
#ResponseBody
public String examplePost(#RequestParam Map<String,String> allParams) {
return "Parameters are " + allParams.entrySet();
}
I went through so many links like How to show all controllers and mappings in a view and How to configure a default #RestController URI prefix for all controllers? and so on.
I want to get the Request Mapping URL at Filter interceptor
Ex: This URL I configured at REST controller method, and naturally we will pass /employees/employee-names/John to get the Employee John.
/employees/employee-names/{employee_name}
Now, when somebody hit /employees/employee-names/John I want to get the value of actual mapping url if REST controller /employees/employee-names/{employee_name},
Any pointers how to get that ?
Spring MVC sets the attribute HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE, which you can use to get the pattern that was used to match the incoming request:
String matchingPattern = (String) request.getAttribute(HandlerMapping.BEST_MATCHING_PATTERN_ATTRIBUTE)
That would return /employees/employee-names/{employee_name} in your case.
I was able to solve this issue using below code. AntPathMatcher is the perfect way to identify if the incoming request and URL you configured in the property file matches exactly. This solution works greatly for me.
AntPathMatcher springMatcher = new AntPathMatcher();
Optional<String> antMatch = props.getMapping().stream()
.filter(//Perform Some Filter as per need)
.map(Mapping::getVersion)
.findFirst();
return antMatch.isPresent() ? antMatch.get() : null;
In short this is what I'm searching for: I want to create a RequestMapping that catches all URLs except a small list I don't want to catch.
The minimum to exclude is everything below /webjars/, I also would like to exclude other URLS like /actuator/ and probably more.
Background information
We need to replace an old CMS which has literally thousands of different URLs. All URLs need to be detected and checked against a database and then the users shall be presented with a landing page, this landing page will then redirect the user to the new CMS target URL.
The logic that needs to be applied is too complicated for some Apache / nginx magic, therefore I wrote a Spring Boot application that can accomplish this.
I've created a #RequestMapping(value = "**", method = RequestMethod.GET) that catches all GET requests (these are the one I want to grab and react on) and a #RequestMapping(value = "**") for the other http verbs like POST and DELETE which I simply abort by sending a http error status code.
This works fine and the (simplified) code looks like this:
#RequestMapping(value = "**", method = RequestMethod.GET)
public String catchAccepted(HttpServletRequest request, HttpServletResponse httpServletResponse, Model model) {
model.addAttribute("targetUrl", ua.deriveNewUrl(request));
return "redirect";
}
#RequestMapping(value = "**")
#ResponseBody
public ResponseEntity<Object> catchDenied(HttpServletRequest request, HttpServletResponse httpServletResponse) {
return new ResponseEntity<Object>(HttpStatus.I_AM_A_TEAPOT);
}
The page that gets displayed for all the GET requests is based on a Thymeleaf template which uses Bootstrap in order to do the layout job.
In order to include Bootstrap I use the webjars-locator and org.webjars.bootstrap, the resources are included by specifying <script src="/webjars/bootstrap/js/bootstrap.min.js"></script> in the redirect.html Thymeleaf template.
Problem
The problem is, that my ** mapping on GET also gets applied to the /webjars/... call and instead of the desired js code I get whatever my redirect template returns.
I found no way to tell Spring Boot about the desired order.
First I would like to have Spring Boot handle the webjars mapping, then my other mapping.
Attempts so far
I checked other posts on SO but they only work when I have access to the sourcecode where the mapping is made. And I don't have access to the webjars locator / see no point in changing it just to solve this issue.
I also tried to set up a "anything that is not related to webjars" mapping like this:
#RequestMapping(value = "^(?!webjars$|actuator$).*", method = RequestMethod.GET)
But this doesn't have the desired effect because the RequestMapping only seems to support ant-stlye paths, which doesn't support negations because Ant (in contrast to Spring Boot) has a field for includes and excludes: https://ant.apache.org/manual/dirtasks.html
Negating the mapping seems only to be possible for params, not for the path: Change #RequestMapping order
I didn't yet find a way to influence the order if other mappings come from code I can not incluence.
But I found a way to configure "catch all except of ...":
#RequestMapping(value = { "", "/", "{url:(?!webjars$|actuator$).*}/**" }, method = RequestMethod.GET)
This configures three mappings. The first two are there to handle calls to the root of the webserver. The third configures a path pariable which I could also put into a #PathVariable but in my scenario the value doesn't matter. If you configure a path variable you need to give it a default because the pattern will only be satisfied depending on the value of your URL.
The regex tells Spring Boot only to react if the url doesn't contain webjars or actuator. The regex itself is best explained by using regex101:
I've been struggling with passing some value between controller.
I have one controller like this:
#RequestMapping(value = "/add", method = RequestMethod.GET)
public String addGet(HttpServletRequest request, #ModelAttribute(value="branch") Branch branch, Model model, blahblahblah)
//What I want to pass and re use:
String loadRespond;
try{
loadRespond= *SOME LOAD STRING METHOD*;
branch= branchManager.convertString(loadRespond); //METHOD TO SPLIT STRING & INDUCT TO OBJECT
}catch{exception){
//blabla
}
After I successfully inducted all the attributes into the object branch,i show them all through a binding form. What i want to do is, when i'm going to update the data/change some attribute, i want to compare the old branch to the new changed branch. This means that i have to pass the old branch object or the loadRespond string onto the POST method so that can be used. Do anyone have any idea of how to do this? Maybe to assign it to hidden type field in the jsp? and then use it on the controller with request mapping /add of method type post? Thanks..I'm a newbie..
Why don't you try out with session scope ?
store your old branch into the session . and when you get the new object compare with the old one (by retrieving from session)
You can save into session as any of both,
request.getSession().setAttribute("sessionvar", "session value");
#SessionAttributes("sessionvar")
A nice Example here to start with it.
Side-note : your question title doesnt quite expalain your problem and the solutions may vary
As San Krish notes in his answer the most common way is to use #SessionAttributes and pass objects/data using them.
This is useful if you don't worry about user moving backwards and forwards in a page, or want basic control of the object.
Now if you want to have a chain where controller 1 passes to controller 2 which may pass to controller 3 your best bet is to implement web flows.
Summary:
For short and sweet and quick: SessionAttributes is the way to go, example here http://www.intertech.com/Blog/understanding-spring-mvc-model-and-session-attributes/
For chain passing, greater control and validation use Spring Web Flows.
What I'm trying to do is to have an api request like /api/calculator?1=7.00&2=9.99&3=5.50&4=45.76 etc. How my controller can grab the request data? The keys/codes of the query string are ints between 1 and 1000. In the query string they can be some of the 1000 codes, not necessarily all of them. The value part is doubles.
The one way I think would work is if I create a model object (ex StupidObject) with 1000 properties (should use properties named like p1, p2,..p1000 for codes now, as ints are not an allowed property name), decorated with ModelBinder. Then for the controller I could have something like GetCalcResult(StupidObject obj){...} But that doesn't seem like an elegant solution :)
I tried controllers like GetCalcResult([FromURI]Dictionary<int, double> dict){...} but dict is always null. Also without the [FromURI] I get an error. Also tried List<KeyValuePair<int, double>> as controller parameter with the same results.
Could anyone point me at the right direction or give me an working example?
One way is to avoid trying to pass the values in as a parameter and simply do
var queryValues = Request.RequestUri.ParseQueryString();
in your action method. QueryValues will be NameValueCollection that you can iterate over to get access to your query parameters.
If you really want to use a parameter, having a parameter of type [FromUri]FormDataCollection might work.