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();
}
Related
I have a Rest service where get call if I send multiple invalid/extra & and = characters then also my endpoint does not throw any error. I would like to throw back invalid request error if url contains any extra special character like & or =.
for example:
http://localhost:8080/myservice?rollNo=03456789321&school=Myschool //This is Okay for me
http://localhost:8080/myservice?rollNo=03456789321&school= //should throw error as school is not having value
http://localhost:8080/myservice?rollNo=03456789321&&&&school=Myschool
//should throw error as &&&& is multiple where it should only one
http://localhost:8080/myservice?rollNo=03456789321&= //should throw error as &= is there at end having no sence.
Note that , I am hitting these request from postman , and I have doubt that postman do something with these parameters, cause I am not able to find these extra characters in spring boot while debugging.
Any way through which i can get whole request url in my controller so that I can find out for these charecters comming?
Any built in springboot annotation is there to handle such a cases?
I got my problem solved.
After lot of research , and some observation I came to know that when you pass any number of characters among & and = in request url, the rest client tools like postman , or advanced rest client will refine the url before hitting actual server and remove those extra un-necessary characters. SO if you write multiple &&&& or == charecters in url , it will consider each extra & as blank parameter and will ignore while sending final request, only of those characters which has parameter names besides it it will taken as part of refined request.
you can see in screenshot bellow:
You can Use #RequestParam in your Spring Boot rest Controller
Something of the following
#GetMapping(value = "/myservice")
public boolean doSomething(#RequestParam("rollNo") Integer rollNo , #RequestParam("school") String school) {
doValidation(rollNo,school);
// Do Something
return true;
}
#RequestParam will make sure that your Url need to have these Params rollNo & school. Without it it will throw error.
But if you were to pass an empty string like &school= in your second example. The controller will get an empty String.
You can add a basic validation layer right before you do anything in you controller to handle this condition.
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.
We are building a RESTful API with several #RestControllers which return all kinds of objects including byte arrays (actually application/pdf).
When an exception occurs we handle those with #RestControllerAdvices which return a custom ErrorView object. Still spring insists of rendering those as application/pdf which of course is not possible. The client is sending application/json in the accept header but this does not seem to help. Any pointers how to fix this?
Ok, I made a mistake which I think I should share.
Basically most of the time the content type negotiation between Spring and the client works like a charm. If the client accepts (as is the case for our app) "application/pdf, application/json" then spring will try to work it our for all responses AKA return values from #RestController functions. Except, of course, when you explicitly tell Spring to only produce a certain type of response e.g. with
#GetMapping(value = "render/document/{docId}", produces = arrayOf(MediaType.APPLICATION_PDF_VALUE))
After changing this to
#GetMapping(value = "render/document/{docId}", produces = arrayOf(MediaType.APPLICATION_PDF_VALUE, MediaType.APPLICATION_JSON_VALUE))
the ErrorView gets rendered as JSON as intended.
I'm trying to use the RestTemplate to send a request with the following format:
http://host:port/action?loc=x,y&t=z&loc=x1,y1&t=z1...
What's important is that the ordering of parameters matters. In this case the each t refers to location previous loc.
No matter how I try to set the parameters for the RestTemplate the resulting request parameters get reordered. All loc parameters appear before all t like this: http://host:port/action?loc=x,y&loc=x1,y1&loc=...&t=z1&t=z2&t=...
Is there any way to prevent RestTemplate from reordering the request parameters.
Thank you.
If you have multiple parameters with the same name, in your case multiple instances of loc - it is treated as an array, that's why they're all coupled together.
I have a RESTful URL that requires either the offset or the prefix request parameter (but not both).
GET /users?offset=0&count=20
GET /users?prefix=J&count=20
What's the best way to enforce this rule? Spring has the #RequestParam annotation with the 'required' property for optional parameters, but I want to enforce an "either-or" rule on these two parameters. I know I could do it in the code, but is there another way to do it?
Also, what's the proper way to handle "impractical" requests? Say I have 100 million users; the following request, although properly RESTful, is not something I want to support:
GET /users <-- Gets all 100 million users, crashes server and browser!
What should I send back?
You can create two methods and choose one of them with #RequestMapping's params attribute:
#RequestMapping(..., params = {"prefix", "!offset"})
public String usersWithPrefix(#RequestParam("prefix") ...) { ... }
#RequestMapping(..., params = {"offset", "!prefix"})
public String usersWithOffset(#RequestParam("offset") ...) { ... }
what's the proper way to handle "impractical" requests?
The lesser-practiced principles of REST include the requirement that resources be "discoverable". If you are asked for a complete list of 800 million users and you don't want to provide it, you might instead consider serving a page that describes in some way how to filter the collection: for example, an XForms document or HTML containing a FORM element with fields for offset/prefix/count, or a URI template with the appropriate parameters
Or you could just send a "413 Entity too large" error - edit: no you can't. Sorry, I misread the description of whath this code is for
If you decide to go down the route of just sending the first page, I think I would send it as an HTTP redirect to /users?offset=0&count=20 so that the client has a better idea they've not got the full collection (and if your response contains a link to access subsequent pages, even better)