Jersey Exception mappers not working when jackson deserialization fails - java

I am using Jersey 2.10 with Jackson serialization/deserialization feature in my REST API.
My idea is to make my REST API to always return a standard JSON error response. For that I have ExceptionMapper classes that build proper json error responses for any exception being thrown in the Jersey application. I also have a jsp which produces the same kind of JSON response, which I registered as error-page in the web.xml that covers all the errors that could come before Jersey being loaded.
But there is one case in which neither my Exception mappers nor my json producing jsp are working, that is when sending a bad formed json to a POST REST endpoint which just returns the following message:
HTTP/1.1 400 Bad Request
Server: Apache-Coyote/1.1
Access-Control-Allow-Origin: *
Access-Control-Allow-Methods: GET, POST, DELETE, PUT
Content-Type: text/plain
Content-Length: 210
Date: Tue, 24 Jun 2014 22:14:11 GMT
Connection: close
Can not deserialize instance of com.example.rest.User[] out of START_OBJECT token
at [Source: org.glassfish.jersey.message.internal.EntityInputStream#1dcccac; line: 1, column: 1]
How can I make Jersey to return my custom error response instead of this?
UPDATE:
Based on the answer by #Lucasz, I did more research and found that there are two Exception mappers defined inside the package com.fasterxml.jackson.jaxrs.base (https://github.com/FasterXML/jackson-jaxrs-providers/tree/master/base/src/main/java/com/fasterxml/jackson/jaxrs/base) JsonMappingExceptionMapper and JsonParseExceptionMapper that seem to be shadowing my custom mappers.
How can I unregister those mappers?
This is how I am currently registering the mappers:
#ApplicationPath("/")
public class MyApp extends ResourceConfig{
public SyntheticAPIApp() {
packages("com.example.resource", "com.example.mapper");
register(org.glassfish.jersey.jackson.JacksonFeature.class);
}
}

I tested it with an exception mapper like below:
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;
import com.fasterxml.jackson.core.JsonProcessingException;
#Provider
public class JsonProcessingExceptionMapper implements ExceptionMapper<JsonProcessingException>{
public static class Error {
public String key;
public String message;
}
#Override
public Response toResponse(JsonProcessingException exception) {
Error error = new Error();
error.key = "bad-json";
error.message = exception.getMessage();
return Response.status(Status.BAD_REQUEST).entity(error).build();
}
}
and it worked.
Update: changed JsonParseException to JsonProcessingException (more general)
Update2:
In order to avoid registering the unwanted mappers replace
register(org.glassfish.jersey.jackson.JacksonFeature.class);
with
register(com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider.class);
Look at the source code of JacksonFeature and you'll understand what's happening.

Starting with Jersey 2.26 (1, 2) it should be enough to annotate the custom exception mapper with a sufficiently high Priority (high here meaning a low, strictly positive number). To override the “default” mappers provided by org.glassfish.jersey.media:jersey-media-json-jackson (to register(JacksonFeature.class)) we only provide these two custom mappers:
#Provider
#Priority(1)
public class JsonMappingExceptionMapper implements ExceptionMapper<JsonMappingException> {
/* ... */
}
#Provider
#Priority(1)
public class JsonParseExceptionMapper implements ExceptionMapper<JsonParseException> {
/* ... */
}
Unfortunately JAX-RS 2 Spec disregards priorities and only states:
When choosing an exception mapping provider to map an exception,
an implementation MUST use the provider whose generic type is the nearest superclass of the exception.
Not registering JacksonFeature.class and registering JacksonJaxbJsonProvider.class instead as mentioned in another answer did not lead to consistent results.

I had the same problem, and the previous answer led me to the solution, but was not forking for me current Jersey (2.22). At first, I needed to use the org.glassfish.jersey.spi.ExtendedExceptionMapper like described in https://jersey.java.net/documentation/latest/representations.html.
Furthermore, Jersey is checking for an exception mapper, which is as close as possible to the thrown exception (from org.glassfish.jersey.internal.ExceptionMapperFactory):
for (final ExceptionMapperType mapperType : exceptionMapperTypes) {
final int d = distance(type, mapperType.exceptionType);
if (d >= 0 && d <= minDistance) {
final ExceptionMapper<T> candidate = mapperType.mapper.getService();
if (isPreferredCandidate(exceptionInstance, candidate, d == minDistance)) {
mapper = candidate;
minDistance = d;
if (d == 0) {
// slight optimization: if the distance is 0, it is already the best case, so we can exit
return mapper;
}
}
}
}
Therefore I needed to map exactly the exception and not a more general exception.
In the end, my provider looks as follows:
#Provider
public final class JsonParseExceptionExceptionHandler implements ExtendedExceptionMapper<JsonParseException> {
#Override
public Response toResponse(final JsonParseException exception) {
exception.printStackTrace();
return Response.status(Response.Status.BAD_REQUEST).entity("JSON nicht in korrektem Format.").build();
}
#Override
public boolean isMappable(final JsonParseException arg0) {
return true;
}
}

I used "jackson-jaxrs-json-provider 2.8.8" and JAX-RS 2.0
Application class - you needs to register your ExceptionMapper implementation class:
#ApplicationPath("pathApplication")
public class ApplicationConfiguration extends Application{
#Override
public Set<Class<?>> getClasses() {
Set<Class<?>> resources = new HashSet<>();
resources.add(YourJAXRSClass.class);
resources.add(JsonJacksonEM.class); //ExceptionMapper class implementation
//others resources that you need...
return resources;
}
}
ExceptionMapper class implementation:
#Provider
public class JsonJacksonEM implements ExceptionMapper<JsonParseException>{
#Override
public Response toResponse(JsonParseException exception) {
//you can return a Response in the way that you want!
return Response.ok(new YourObject()).build();
}
}

I had the same problem and solve overriding the ExceptionMapper. Perfect! One extra thing that I needed to do and were not understanding 100% was how to override the JacksonProvider for my application (I don't know if it was related to Jersey's version that I was using - 2.19). Here's my web.xml part that overrides it:
<init-param>
<param-name>jersey.config.server.provider.classnames</param-name>
<param-value>
com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider
</param-value>
</init-param>

I have faced this issue recently, and the solution of registering com.fasterxml.jackson.jaxrs.json.JacksonJsonProvider doesn't helped much. When I dig deeper I came to know that Jersey by default org.glassfish.jersey.jackson.JacksonFeature is registered by Jersey, if the dependency jersey-media-json-jackson even without the explicit declaration of registering it(Don't sure from which version the auto register is implemented, I guess atleast from Jersey 2.29) present in the classpath.
The JacksonFeature inturn registers JsonParseExceptionMapper and JsonMappingExceptionMapper automatically. Because of these default JSON exception mappers, all JSON related exceptions are not redirected to the custom exception mapper
Fortunately, Jersey 2.29.1 added support for registering JacksonFeature without the exception handlers. link feature request link, code changes.
#Provider
public class ApplicationConfig extends Application {
#Override
public Set<Object> getSingletons() {
Set<Object> singletons = super.getSingletons();
singletons.add(JacksonFeature.withoutExceptionMappers());
return singletons;
}
}
The above code snippet will override the default JacksonFeature registered by Jersey. By doing so, all JSON-related exceptions will be redirected to custom exception mappers present in the application.

Related

How to provide custom exception mappings for jax-rs endpoints in Magnolia CMS (v 5.5.6)?

I created custom jax-rs based endpoint.
#Path("/test")
public class MyEndpoint<D extends EndpointDefinition> extends AbstractEndpoint<D> {
#Path("/dosth")
#GET
#Produces(MediaType.APPLICATION_JSON)
public void doSth() {
//some code here
}
}
Now I want to add custom exception handling for jax-rs endpoints. I want all exceptions handling in one place, instead of try-catch in every method. Tried to add jax-rs ExceptionMapper:
#Provider
public class CustomExceptionMapper implements ExceptionMapper<Throwable> {
public Response toResponse(Throwable e) {
return Response.status(Response.Status.SERVICE_UNAVAILABLE).build();
}
}
Unfortunately Magnolia doesn't use it. How can I register such mapper i Magnolia 5.5.6?
Custom exception mapper should be registered in rest-integration JCR configuration. The node responsible for jax-rs providers is
config.modules.rest-integration.config.additionalProviders
I've overridden default exception mapper by my custom implementation and now it works.

How to manage REST API versioning with spring?

I've been searching how to manage a REST API versions using Spring 3.2.x, but I haven't find anything that is easy to maintain. I'll explain first the problem I have, and then a solution... but I do wonder if I'm re-inventing the wheel here.
I want to manage the version based on the Accept header, and for example if a request has the Accept header application/vnd.company.app-1.1+json, I want spring MVC to forward this to the method that handles this version. And since not all methods in an API change in the same release, I don't want to go to each of my controllers and change anything for a handler that hasn't changed between versions. I also don't want to have the logic to figure out which version to use in the controller themselves (using service locators) as Spring is already discovering which method to call.
So taken an API with versions 1.0, to 1.8 where a handler was introduced in version 1.0 and modified in v1.7, I would like handle this in the following way. Imagine that the code is inside a controller, and that there's some code that is able to extract the version from the header. (The following is invalid in Spring)
#RequestMapping(...)
#VersionRange(1.0,1.6)
#ResponseBody
public Object method1() {
// so something
return object;
}
#RequestMapping(...) //same Request mapping annotation
#VersionRange(1.7)
#ResponseBody
public Object method2() {
// so something
return object;
}
This is not possible in spring as the 2 methods have the same RequestMapping annotation and Spring fails to load. The idea is that the VersionRange annotation can define an open or closed version range. The first method is valid from versions 1.0 to 1.6, while the second for version 1.7 onwards (including the latest version 1.8). I know that this approach breaks if someone decides to pass version 99.99, but that's something I'm OK to live with.
Now, since the above is not possible without a serious rework of how spring works, I was thinking of tinkering with the way handlers matched to requests, in particular to write my own ProducesRequestCondition, and have the version range in there. For example
Code:
#RequestMapping(..., produces = "application/vnd.company.app-[1.0-1.6]+json)
#ResponseBody
public Object method1() {
// so something
return object;
}
#RequestMapping(..., produces = "application/vnd.company.app-[1.7-]+json)
#ResponseBody
public Object method2() {
// so something
return object;
}
In this way, I can have closed or open version ranges defined in the produces part of the annotation. I'm working on this solution now, with the problem that I still had to replace some core Spring MVC classes (RequestMappingInfoHandlerMapping, RequestMappingHandlerMapping and RequestMappingInfo), which I don't like, because it means extra work whenever I decide to upgrade to a newer version of spring.
I would appreciate any thoughts... and especially, any suggestion to do this in a simpler, easier to maintain way.
Edit
Adding a bounty. To get the bounty, please answer the question above without suggesting to have this logic in the controller themselves. Spring already has a lot of logic to select which controller method to call, and I want to piggyback on that.
Edit 2
I've shared the original POC (with some improvements) in github: https://github.com/augusto/restVersioning
Regardless whether versioning can be avoided by doing backwards compatible changes (which might not always possible when you are bound by some corporate guidelines or your API clients are implemented in a buggy way and would break even if they should not) the abstracted requirement is an interesting one:
How can I do a custom request mapping that does arbitrary evaluations of header values from the request without doing the evaluation in the method body?
As described in this SO answer you actually can have the same #RequestMapping and use a different annotation to differentiate during the actual routing that happens during runtime. To do so, you will have to:
Create a new annotation VersionRange.
Implement a RequestCondition<VersionRange>. Since you will have something like a best-match algorithm you will have to check whether methods annotated with other VersionRange values provide a better match for the current request.
Implement a VersionRangeRequestMappingHandlerMapping based on the annotation and request condition (as described in the post How to implement #RequestMapping custom properties
).
Configure spring to evaluate your VersionRangeRequestMappingHandlerMapping before using the default RequestMappingHandlerMapping (e.g. by setting its order to 0).
This wouldn't require any hacky replacements of Spring components but uses the Spring configuration and extension mechanisms so it should work even if you update your Spring version (as long as the new version supports these mechanisms).
I just created a custom solution. I'm using the #ApiVersion annotation in combination with #RequestMapping annotation inside #Controller classes.
Example:
#Controller
#RequestMapping("x")
#ApiVersion(1)
class MyController {
#RequestMapping("a")
void a() {} // maps to /v1/x/a
#RequestMapping("b")
#ApiVersion(2)
void b() {} // maps to /v2/x/b
#RequestMapping("c")
#ApiVersion({1,3})
void c() {} // maps to /v1/x/c
// and to /v3/x/c
}
Implementation:
ApiVersion.java annotation:
#Target({ElementType.METHOD, ElementType.TYPE})
#Retention(RetentionPolicy.RUNTIME)
public #interface ApiVersion {
int[] value();
}
ApiVersionRequestMappingHandlerMapping.java (this is mostly copy and paste from RequestMappingHandlerMapping):
public class ApiVersionRequestMappingHandlerMapping extends RequestMappingHandlerMapping {
private final String prefix;
public ApiVersionRequestMappingHandlerMapping(String prefix) {
this.prefix = prefix;
}
#Override
protected RequestMappingInfo getMappingForMethod(Method method, Class<?> handlerType) {
RequestMappingInfo info = super.getMappingForMethod(method, handlerType);
if(info == null) return null;
ApiVersion methodAnnotation = AnnotationUtils.findAnnotation(method, ApiVersion.class);
if(methodAnnotation != null) {
RequestCondition<?> methodCondition = getCustomMethodCondition(method);
// Concatenate our ApiVersion with the usual request mapping
info = createApiVersionInfo(methodAnnotation, methodCondition).combine(info);
} else {
ApiVersion typeAnnotation = AnnotationUtils.findAnnotation(handlerType, ApiVersion.class);
if(typeAnnotation != null) {
RequestCondition<?> typeCondition = getCustomTypeCondition(handlerType);
// Concatenate our ApiVersion with the usual request mapping
info = createApiVersionInfo(typeAnnotation, typeCondition).combine(info);
}
}
return info;
}
private RequestMappingInfo createApiVersionInfo(ApiVersion annotation, RequestCondition<?> customCondition) {
int[] values = annotation.value();
String[] patterns = new String[values.length];
for(int i=0; i<values.length; i++) {
// Build the URL prefix
patterns[i] = prefix+values[i];
}
return new RequestMappingInfo(
new PatternsRequestCondition(patterns, getUrlPathHelper(), getPathMatcher(), useSuffixPatternMatch(), useTrailingSlashMatch(), getFileExtensions()),
new RequestMethodsRequestCondition(),
new ParamsRequestCondition(),
new HeadersRequestCondition(),
new ConsumesRequestCondition(),
new ProducesRequestCondition(),
customCondition);
}
}
Injection into WebMvcConfigurationSupport:
public class WebMvcConfig extends WebMvcConfigurationSupport {
#Override
public RequestMappingHandlerMapping requestMappingHandlerMapping() {
return new ApiVersionRequestMappingHandlerMapping("v");
}
}
I have implemented a solution which handles PERFECTLY the problem with rest versioning.
General Speaking there are 3 major approaches for rest versioning:
Path-based approch, in which the client defines the version in URL:
http://localhost:9001/api/v1/user
http://localhost:9001/api/v2/user
Content-Type header, in which the client defines the version in Accept header:
http://localhost:9001/api/v1/user with
Accept: application/vnd.app-1.0+json OR application/vnd.app-2.0+json
Custom Header, in which the client defines the version in a custom header.
The problem with the first approach is that if you change the version let's say from v1 -> v2, probably you need to copy-paste the v1 resources that haven't changed to v2 path
The problem with the second approach is that some tools like http://swagger.io/ cannot distinct between operations with same path but different Content-Type (check issue https://github.com/OAI/OpenAPI-Specification/issues/146)
The solution
Since i am working a lot with rest documentation tools, i prefer to use the first approach. My solution handles the problem with the first approach, so you don't need to copy-paste the endpoint to the new version.
Let's say we have v1 and v2 versions for the User controller:
package com.mspapant.example.restVersion.controller;
import io.swagger.annotations.Api;
import io.swagger.annotations.ApiOperation;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
/**
* The user controller.
*
* #author : Manos Papantonakos on 19/8/2016.
*/
#Controller
#Api(value = "user", description = "Operations about users")
public class UserController {
/**
* Return the user.
*
* #return the user
*/
#ResponseBody
#RequestMapping(method = RequestMethod.GET, value = "/api/v1/user")
#ApiOperation(value = "Returns user", notes = "Returns the user", tags = {"GET", "User"})
public String getUserV1() {
return "User V1";
}
/**
* Return the user.
*
* #return the user
*/
#ResponseBody
#RequestMapping(method = RequestMethod.GET, value = "/api/v2/user")
#ApiOperation(value = "Returns user", notes = "Returns the user", tags = {"GET", "User"})
public String getUserV2() {
return "User V2";
}
}
The requirement is if i request the v1 for the user resource i have to take the "User V1" repsonse, otherwise if i request the v2, v3 and so on i have to take the "User V2" response.
In order to implement this in spring, we need to override the default RequestMappingHandlerMapping behavior:
package com.mspapant.example.restVersion.conf.mapping;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
public class VersionRequestMappingHandlerMapping extends RequestMappingHandlerMapping {
#Value("${server.apiContext}")
private String apiContext;
#Value("${server.versionContext}")
private String versionContext;
#Override
protected HandlerMethod lookupHandlerMethod(String lookupPath, HttpServletRequest request) throws Exception {
HandlerMethod method = super.lookupHandlerMethod(lookupPath, request);
if (method == null && lookupPath.contains(getApiAndVersionContext())) {
String afterAPIURL = lookupPath.substring(lookupPath.indexOf(getApiAndVersionContext()) + getApiAndVersionContext().length());
String version = afterAPIURL.substring(0, afterAPIURL.indexOf("/"));
String path = afterAPIURL.substring(version.length() + 1);
int previousVersion = getPreviousVersion(version);
if (previousVersion != 0) {
lookupPath = getApiAndVersionContext() + previousVersion + "/" + path;
final String lookupFinal = lookupPath;
return lookupHandlerMethod(lookupPath, new HttpServletRequestWrapper(request) {
#Override
public String getRequestURI() {
return lookupFinal;
}
#Override
public String getServletPath() {
return lookupFinal;
}});
}
}
return method;
}
private String getApiAndVersionContext() {
return "/" + apiContext + "/" + versionContext;
}
private int getPreviousVersion(final String version) {
return new Integer(version) - 1 ;
}
}
The implementation reads the version in the URL and asks from spring to resolve the URL .In case this URL does not exists (for example the client requested v3) then we try with v2 and so one until we find the most recent version for the resource.
In order to see the benefits from this implementation, let's say we have two resources: User and Company:
http://localhost:9001/api/v{version}/user
http://localhost:9001/api/v{version}/company
Let's say we made a change in company "contract" that breaks the client. So we implement the http://localhost:9001/api/v2/company and we ask from client to change to v2 instead on v1.
So the new requests from client are:
http://localhost:9001/api/v2/user
http://localhost:9001/api/v2/company
instead of:
http://localhost:9001/api/v1/user
http://localhost:9001/api/v1/company
The best part here is that with this solution the client will get the user information from v1 and company information from v2 without the need to create a new (same) endpoint from user v2!
Rest Documentation
As i said before the reason i select the URL-based versioning approach is that some tools like swagger do not document differently the endpoints with the same URL but different content type. With this solution, both endpoints are displayed since have different URL:
GIT
Solution implementation at:
https://github.com/mspapant/restVersioningExample/
I would still recommend using URL's for versioning because in URLs #RequestMapping supports patterns and path parameters, which format could be specified with regexp.
And to handle client upgrades (which you mentioned in comment) you can use aliases like 'latest'. Or have unversioned version of api which uses latest version (yeah).
Also using path parameters you can implement any complex version handling logic, and if you already want to have ranges, you very well might want something more soon enough.
Here is a couple of examples:
#RequestMapping({
"/**/public_api/1.1/method",
"/**/public_api/1.2/method",
})
public void method1(){
}
#RequestMapping({
"/**/public_api/1.3/method"
"/**/public_api/latest/method"
"/**/public_api/method"
})
public void method2(){
}
#RequestMapping({
"/**/public_api/1.4/method"
"/**/public_api/beta/method"
})
public void method2(){
}
//handles all 1.* requests
#RequestMapping({
"/**/public_api/{version:1\\.\\d+}/method"
})
public void methodManual1(#PathVariable("version") String version){
}
//handles 1.0-1.6 range, but somewhat ugly
#RequestMapping({
"/**/public_api/{version:1\\.[0123456]?}/method"
})
public void methodManual1(#PathVariable("version") String version){
}
//fully manual version handling
#RequestMapping({
"/**/public_api/{version}/method"
})
public void methodManual2(#PathVariable("version") String version){
int[] versionParts = getVersionParts(version);
//manual handling of versions
}
public int[] getVersionParts(String version){
try{
String[] versionParts = version.split("\\.");
int[] result = new int[versionParts.length];
for(int i=0;i<versionParts.length;i++){
result[i] = Integer.parseInt(versionParts[i]);
}
return result;
}catch (Exception ex) {
return null;
}
}
Based on the last approach you can actually implement something like what you want.
For example you can have a controller that contains only method stabs with version handling.
In that handling you look (using reflection/AOP/code generation libraries) in some spring service/component or in the same class for method with the same name/signature and required #VersionRange and invoke it passing all parameters.
The #RequestMapping annotation supports a headers element that allows you to narrow the matching requests. In particular you can use the Accept header here.
#RequestMapping(headers = {
"Accept=application/vnd.company.app-1.0+json",
"Accept=application/vnd.company.app-1.1+json"
})
This isn't exactly what you're describing, since it doesn't directly handle ranges, but the element does support the * wildcard as well as !=. So at least you could get away with using a wildcard for cases where all versions support the endpoint in question, or even all minor versions of a given major version (e.g. 1.*).
I don't think I've actually used this element before (if I have I don't remember), so I'm just going off the documentation at
http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/web/bind/annotation/RequestMapping.html
I already tried to version my API using the URI Versioning, like:
/api/v1/orders
/api/v2/orders
But there are some challenges when trying to make this work: how organize your code with different versions? How manage two (or more) versions at the same time? What's the impact when removing some version?
The best alternative that I found was not version the entire API, but control the version on each endpoint. This pattern is called Versioning using Accept header or Versioning through content negotiation:
This approach allows us to version a single resource representation
instead of versioning the entire API which gives us a more granular
control over versioning. It also creates a smaller footprint in the
code base as we don’t have to fork the entire application when
creating a new version. Another advantage of this approach is that it
doesn’t require implementing URI routing rules introduced by
versioning through the URI path.
Implementation on Spring
First, you create a Controller with a produces attribute, that will applied by default on each endpoint inside the same class.
#RestController
#RequestMapping(value = "/api/orders/", produces = "application/vnd.company.etc.v1+json")
public class OrderController {
}
After that, we can imagine a possible scenario where you have two versions (v1 and v2) of an endpoint for "create an order":
#Deprecated
#PostMapping
public ResponseEntity<OrderResponse> createV1(
#RequestBody OrderRequest orderRequest) {
OrderResponse response = createOrderService.createOrder(orderRequest);
return new ResponseEntity<>(response, HttpStatus.CREATED);
}
#PostMapping(
produces = "application/vnd.company.etc.v2+json",
consumes = "application/vnd.company.etc.v2+json")
public ResponseEntity<OrderResponseV2> createV2(
#RequestBody OrderRequestV2 orderRequest) {
OrderResponse response = createOrderService.createOrder(orderRequest);
return new ResponseEntity<>(response, HttpStatus.CREATED);
}
Done! Just call each endpoint using the desired Http Header version:
Content-Type: application/vnd.company.etc.v1+json
Or, to call the v2:
Content-Type: application/vnd.company.etc.v2+json
About your worries:
And since not all methods in an API change in the same release, I
don't want to go to each of my controllers and change anything for a
handler that hasn't changed between versions
As explained, this strategy maintains each Controller and endpoint with his actual version. You only modify the endpoint that have modifications and needs a new version.
And the Swagger?
Setup the Swagger with different versions is also very easy using this strategy. See this answer to more details.
What about just using inheritance to model versioning? That is what I'm using in my project and it requires no special spring configuration and gets me exactly what I want.
#RestController
#RequestMapping(value = "/test/1")
#Deprecated
public class Test1 {
...Fields Getters Setters...
#RequestMapping(method = RequestMethod.GET)
#Deprecated
public Test getTest(Long id) {
return serviceClass.getTestById(id);
}
#RequestMapping(method = RequestMethod.PUT)
public Test getTest(Test test) {
return serviceClass.updateTest(test);
}
}
#RestController
#RequestMapping(value = "/test/2")
public class Test2 extends Test1 {
...Fields Getters Setters...
#Override
#RequestMapping(method = RequestMethod.GET)
public Test getTest(Long id) {
return serviceClass.getAUpdated(id);
}
#RequestMapping(method = RequestMethod.DELETE)
public Test deleteTest(Long id) {
return serviceClass.deleteTestById(id);
}
}
This set up allows for little duplication of code and the ability to overwrite methods into new versions of the api with little work. It also saves the need to complicate your source code with version switching logic. If you don't code an endpoint in a version it will grab the previous version by default.
Compared to what others are doing this seems way easier. Is there something I'm missing?
In produces you can have negation. So for method1 say produces="!...1.7" and in method2 have the positive.
The produces is also an array so you for method1 you can say produces={"...1.6","!...1.7","...1.8"} etc (accept all except 1.7)
Ofcourse not as ideal as ranges that you have in mind but I think easier to maintain than other custom stuff if this is something uncommon in your system. Good luck!
You can use AOP, around interception
Consider having a request mapping which receives all the /**/public_api/* and in this method do nothing;
#RequestMapping({
"/**/public_api/*"
})
public void method2(Model model){
}
After
#Override
public void around(Method method, Object[] args, Object target)
throws Throwable {
// look for the requested version from model parameter, call it desired range
// check the target object for #VersionRange annotation with reflection and acquire version ranges, call the function if it is in the desired range
}
The only constraint is that all has to be in the same controller.
For AOP configuration have a look at http://www.mkyong.com/spring/spring-aop-examples-advice/

Use ContainerRequestFilter in Jersey without web.xml

I am trying to intercept requests in Jersey running inside Glassfish.
I created an implementation of ContainerRequestFilter
package mycustom.api.rest.security;
#Provider
public class SecurityProvider implements ContainerRequestFilter {
#Override
public ContainerRequest filter(ContainerRequest request) {
return request;
}
}
My app is started using a subclass of PackagesResourceConfig.
When Glassfish starts, Jerseys find my provider:
INFO: Provider classes found:
class mycustom.rest.security.SecurityProvider
But it never hits that filter method. What am I missing??
Everything else seems to be working fine. I added a couple of ContextResolver providers to do JSON mapping and they work fine. Requests hit my resources fine, it just never goes through the filter.
I don't think container filters are loaded in as providers. I think you have to set the response filters property. Strangely PackagesResourceConfig doesn't have a setProperty() but you could overload getProperty() and getProperties():
public Object getProperty(String propertyName) {
if(propertyName.equals(ResourceConfig.PROPERTY_CONTAINER_REQUEST_FILTERS)) {
return new String[] {"mycustom.rest.security.SecurityProvider"};
} else {
return super.getProperty(propertyName);
}
}
public Map<String,Object> getProperties() {
propName = ResourceConfig.PROPERTY_CONTAINER_REQUEST_FILTERS;
Map<String,Object> result = super.getProperties();
result.put(propName,getProperty(propName));
return result;
}
Actually, reading the javadocs more closely, it appears the preferred method is:
myConfig.getProperties().put(ResourceConfig.PROPERTY_CONTAINER_REQUEST_FILTERS,
new String [] {"mycustom.rest.security.SecurityProvider"});

Jersey: Error when a class has both JAX-RS and JAX-WS annotations

Using Jersey 1.7, JAX-WS 2.2.3, Tomcat 6.0.30 and the following method declaration prevents Jersey servlet to start:
#POST
#Produces("text/plain")
public void postIt(#WebParam(name = "paramOne") final String paramOne,
final String paramTwo) {
// ...
}
The generated exception is:
SEVERE: Missing dependency for method public
java.lang.String com.sun.jersey.issue.MyResource.postIt(
java.lang.String,java.lang.String) at parameter at index 0
SEVERE: Method, public void
com.sun.jersey.issue.MyResource.postIt(
java.lang.String,java.lang.String),
annotated with POST of resource,
class com.sun.jersey.issue.MyResource,
is not recognized as valid resource method.
If the #WebParam annotation is removed, it all works fine.
Now, please have in mind that I am not trying to work with mere strings, rather, I am migrating complicated Objects that got marshalled/unmarshalled using SOAP to RESTful services, but I must provide both interfaces for a while, without breaking the previous WASDs. The method is just a minimalistic scenario.
Has any of you any idea of the status of this? Has it been fixed? Suggestions?
The specification is clear on this. Section 3.3.2.1 tells us that:
Resource methods MUST NOT have more
than one parameter that is not
annotated with one of the above listed
annotations.
The above listed annotations are the JAX-RS parameter annotations: #QueryParam, #MatrixParam, etc.
There is, however, a Jersey specific way to solve this problem. Using InjectableProvider. So, a method that defines two non-JAX-RS parameters:
#POST
public void postIt(#CustomInjectable final Customer customer,
final Transaction transaction) {
// ...
}
Of course, we have to code the annotation:
#Retention(RetentionPolicy.RUNTIME)
#Target(ElementType.PARAMETER)
public #interface CustomInjectable {
}
An implementation of InjectableProvider that knows how to provide Customers:
import com.sun.jersey.spi.inject.Injectable;
import com.sun.jersey.spi.inject.InjectableProvider;
import com.sun.jersey.api.model.Parameter;
#Provider
public class CustomerInjectableProvider implements
InjectableProvider<CustomInjectable, Parameter> {
// you can use #Context variables, as in any Provider/Resource
#Context
private Request request;
public ComponentScope getScope() {
// ComponentScope.Singleton, Request or Undefined
}
public Injectable getInjectable(ComponentContext i,
CustomInjectable annotation,
Parameter param) {
Injectable injectable = null;
if (Customer.getClass().isAssignableFrom(param.getParameterClass()) {
injectable = getInjectable();
}
return injectable;
}
private Injectable getInjectable() {
return new Injectable<Customer>() {
public Customer getValue() {
// parse the customer from request... or session... or whatever...
}
};
}
}
But, Jersey considers only the last annotation (see JERSEY-ISSUE-731), so be careful.
And, a more portable way (if you do care about that, anyway):
// simple bean
public class CustomerWithTransaction {
private Customer customer;
private Transaction transaction;
// getters and setters
}
Then change the method to:
#POST
public void postIt(CustomerWithTransaction customerWithTransaction) {
// ...
}
Then create your own MessageBodyReader for CustomerWithTransaction, where you can also access any context variables (request, headers, etc.).

Jersey does not see my MessageBodyReader

I'm trying to use jersey with my own json MessageBodyReader/MessageBodyWriter (as I am not use #XmlRootElement... annotations on my domain classes).
#Provider
#Produces(MediaType.APPLICATION_JSON)
#Consumes(MediaType.APPLICATION_JSON)
public final class MyGsonMessageBodyHandler implements MessageBodyWriter<Object>, MessageBodyReader<Object> {
...
}
Jersey uses this class as messagebodywriter (as it stops at breakpoint in the implemented method writeTo). Hovewer it does not see this class as messagebodyreader (and even when I break up this class to the separate implementations of the messagebodyreader/messagebodywriter it still refuses to use my messagebodyreader).
The testing code looks as follows (jersey-grizzly):
final Greeting greeting = resource.path("/greeting")
.queryParam("name", name)
.accept(MediaType.APPLICATION_JSON)
.type(MediaType.APPLICATION_JSON)
.get(Greeting.class);
The error I got looks as follows:
A message body reader for Java class test.Greeting, and Java type class test.Greeting, and MIME media type application/json was not found
I'm wondering what kind of magic is required for writing own MessageBodyReader?
After a while I found a root cause of the issue. My implementation of MessageBodyReader/Writer is OK (and I it works fine with RESTlet), but IF YOU USE JerseyTest, DO NOT FORGET TO ADD YOUR MessageBodyReader/Writer to it's ClientConfig:
/**
* Creates custom REST client config which is mandatory since we don't use any JSON providers.
* #return Jersey Client Config with the required classes to read/write in(out)coming data.
*/
private static ClientConfig createClientConfig() {
final ClientConfig config = new DefaultClientConfig();
config.getClasses().add(GsonMessageBodyHandler.class);
config.getClasses().add(GsonAwareContextResolver.class);
return config;
}
/**
* Public ctor
* #throws com.sun.jersey.test.framework.spi.container.TestContainerException On error
*/
public MyRestExposureTest() throws TestContainerException {
super(new WebAppDescriptor.Builder("my.rest.package")
.clientConfig(createClientConfig())
.contextPath("/")
.build());
}
Otherwise your client code would be unable to read/write your POJOs.
This is what I'm using and it's working (currently with Jersey 1.8).
public static Client createMyClient() {
ClientConfig cc = new DefaultClientConfig();
cc.getClasses().add(MyProviderClass1.class);
cc.getClasses().add(MyProviderClass2.class);
cc.getClasses().add(MyProviderClass3.class);
return Client.create(cc);
}
I'm not sure if it's your case, but the common mistake is incorrect implementation of isReadable method.
Did you implemented it?
Do you stop there, when debugging?
Does it return true?
After trying Alex' solution, this finally worked for me:
public IntegrationTest() throws TestContainerException {
super(new LowLevelAppDescriptor.Builder(createResourceConfig())
.build());
}
private static ResourceConfig createResourceConfig() {
ResourceConfig rc = new PackagesResourceConfig("com.github.joschi.jersey.security.smime");
rc.getSingletons().add(new EnvelopedWriter());
rc.getSingletons().add(new SignedWriter());
return rc;
}

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