I have a Spring 3.2 Controller with basic request mappings like
#RequestMapping("/action")
public String action(#RequestParam("param") String param) {
//do stuff...
return "view";
}
This controller handles links created by non-technical business users. Sometimes the users mess it up and create links with duplicate parameters, e.g.,
www.example.com/action?param=value¶m=value
The parameter is an exact duplicate and probably a copy/paste error.
My problem is that Spring is concatenating these dupes together, so that the url above will give "value,value" for param, when I want only "value".
What is a good way to detect and handle these duplicates? I know I could change all my #RequestParams to List<String>s and go from there, but that's a whole lot of boilerplate over dozens of request mappings.
Ideally there would be a way to intercept and modify the url parameters before Spring attempts to bind them -- but only for this controller.
I found that I can register a custom String property editor to do this.
class DuplicateParameterReducingPropertyEditor extends PropertyEditorSupport {
Object value;
#Override
public void setValue(Object value) {
if (value instanceof String[]) {
String[] strings = (String[])value;
Set<String> unique = Sets.newHashSet(strings);
this.value = unique.toArray();
} else {
this.value = value;
}
}
#Override
public void setAsText(String text) throws IllegalArgumentException {
this.value = text;
}
#Override
public String getAsText() {
return value.toString();
}
#Override
public Object getValue() {
return value;
}
};
I added this to my controller:
#InitBinder
public void initBinder(WebDataBinder binder) {
PropertyEditor stringEditor = new DuplicateParameterReducingPropertyEditor();
binder.registerCustomEditor(String.class, stringEditor);
}
So whenever Spring encounters a #RequestParam-annotated String method argument, the PropertyEditor is invoked to transform the incoming data if needed. In the case of duplicate parameters, Spring passes a String[] of the values to the property editor setValue, which I can then manipulate.
This does have the results I am looking for. I'm not sure of all the implications of this, though, so I can't endorse it as good solution yet. Not having to alter any handler method signatures is a big plus though.
A good idea would be to extend AbstractNamedValueMethodArgumentResolver with your own strategy. Then the strategy could be used wherever you deem necessary.
This strategy only works for Spring 3.1+ which is not a problem for you since you are using Spring 3.2
I faced the same issue in Spring boot. Eventually I came up with this solution using converter, in case it helps anyone.
This method should be added as part of your WebMvcConfigurer class.
#Override
public void addFormatters(FormatterRegistry registry) {
// Duplicate query parameters converter
registry.addConverter(new Converter<String[], String>() {
public String convert(String[] arr) {
return arr[arr.length - 1]; // Return the last value
}
});
}
Related
I am attempting to authorize against an external identity provider. Everything seems setup fine, but I keep getting a validation error with my identity provider because the state parameter automatically tacked onto my authorization request is not long enough:
For example:
&state=uYG5DC
The requirements of my IDP say that this state param must be at least 32-characters long. How can I programmatically increase the size of this auto-generated number?
Even if I could generate this number myself, it is not possible to override with other methods I have seen suggested. The following attempt fails because my manual setting of ?state=abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz is superceded by the autogenerated param placed after it during the actual request:
#Bean
public OAuth2ProtectedResourceDetails loginGovOpenId() {
AuthorizationCodeResourceDetails details = new AuthorizationCodeResourceDetails() {
#Override
public String getUserAuthorizationUri() {
return super.getUserAuthorizationUri() + "?state=abcdefghijklmnopqrstuvwxyzabcdefghijklmnopqrstuvwxyz";
}
};
details.setClientId(clientId);
details.setAccessTokenUri(accessTokenUri);
details.setUserAuthorizationUri(userAuthorizationUri);
details.setScope(Arrays.asList("openid", "email"));
details.setPreEstablishedRedirectUri(redirectUri);
details.setUseCurrentUri(true);
return details;
}
The 6-character setting seems to be set here, is there a way to override this?
https://github.com/spring-projects/spring-security-oauth/blob/master/spring-security-oauth2/src/main/java/org/springframework/security/oauth2/common/util/RandomValueStringGenerator.java
With the help of this post:
spring security StateKeyGenerator custom instance
I was able to come up with a working solution.
In my configuration class marked with these annotations:
#Configuration
#EnableOAuth2Client
I configured the following beans:
#Bean
public OAuth2ProtectedResourceDetails loginGovOpenId() {
AuthorizationCodeResourceDetails details = new AuthorizationCodeResourceDetails();
AuthorizationCodeResourceDetails details = new
details.setClientId(clientId);
details.setClientSecret(clientSecret);
details.setAccessTokenUri(accessTokenUri);
details.setUserAuthorizationUri(userAuthorizationUri);
details.setScope(Arrays.asList("openid", "email"));
details.setPreEstablishedRedirectUri(redirectUri);
details.setUseCurrentUri(true);
return details;
}
#Bean
public StateKeyGenerator stateKeyGenerator() {
return new CustomStateKeyGenerator();
}
#Bean
public AccessTokenProvider accessTokenProvider() {
AuthorizationCodeAccessTokenProvider accessTokenProvider = new AuthorizationCodeAccessTokenProvider();
accessTokenProvider.setStateKeyGenerator(stateKeyGenerator());
return accessTokenProvider;
}
#Bean
public OAuth2RestTemplate loginGovOpenIdTemplate(final OAuth2ClientContext clientContext) {
final OAuth2RestTemplate template = new OAuth2RestTemplate(loginGovOpenId(), clientContext);
template.setAccessTokenProvider(accessTokenProvider());
return template;
}
Where my CustomStateKeyGenerator implementation class looks as follows:
public class CustomStateKeyGenerator implements StateKeyGenerator {
// login.gov requires state to be at least 32-characters long
private static int length = 32;
private RandomValueStringGenerator generator = new RandomValueStringGenerator(length);
#Override
public String generateKey(OAuth2ProtectedResourceDetails resource) {
return generator.generate();
}
}
With #RequestMapping, request can be associated with different controller functions through header or request parameters. Is there a way to achieve this base on the user user role? The aim is avoid if statement in the controller.
As far as I am aware, there is not anything that comes out of the box, but if you wanted to you could probably create a custom mapping annotation to do this routing for you.
I have not actually tried any of this code, but something like:
Your new annoation, used like #UserRoleMapping("ROLE_ADMIN")
#Target( ElementType.TYPE )
#Retention(RetentionPolicy.RUNTIME)
public #interface UserRoleMapping {
String[] value();
}
Next, you can just extend the standard Spring RequestMappingHandlerMapping class (this is the class that handles the standard mapping of #RequestMapping annotations). You just need to tell the mapping handler to also take into account a custom condition:
public class UserRoleRequestCondition extends RequestMappingHandlerMapping {
#Override protected RequestCondition<?> getCustomTypeCondition(Class<?> handlerType) {
UserRoleMapping typeAnnotation = AnnotationUtils.findAnnotation(handlerType, UserRoleMapping.class);
return (typeAnnotation != null) ? new UserRoleRequestCondition( typeAnnotation.value() ) : null;
}
}
The above code just checks the controller for your new annotation created above and if it is found it returns a new condition class, constructed with the value you have set in the annotation (e.g. "ROLE_ADMIN"). This MappingHandler will need to be set in your Spring config (whereever you are currently setting the RequestMappingHandlerMapping, just replace it with one of these).
Next we need to create the custom condition - this is the guy that is going to be invoked on request to determine if a request matches the controller:
public class UserRoleRequestCondition implements RequestCondition<UserRoleRequestCondition> {
private final Set<String> roles;
public UserRoleRequestCondition( String... roles ) {
this( Arrays.asList(roles) );
}
public UserRoleRequestCondition( Collection<String> roles ) {
this.roles = Collections.unmodifiableSet(new HashSet<String>(roles));
}
#Override public UserRoleRequestCondition combine(UserRoleRequestCondition other) {
Set<String> allRoles = new LinkedHashSet<String>(this.roles);
allRoles.addAll(other.roles);
return new UserRoleRequestCondition(allRoles);
}
#Override public UserRoleRequestCondition getMatchingCondition( HttpServletRequest request ) {
UserRoleRequestCondition condition = null;
for (String r : roles){
if ( request.isUserInRole( r ) ){
condition = this;
}
}
return condition;
}
#Override public int compareTo(UserRoleRequestCondition other, HttpServletRequest request) {
return (other.roles - this.roles).size();
}
}
In the above, the method getMatchingCondition is where we match the request. (apologies if I have missed some semi-colons or return keywords etc - this is based on groovy, but hopefully if you are in java you can work out where those bits go!)
Props to Marek for his more detailed answer on the more fully-formed solution to custom routing based on the subdomain that I used when I had to implement something similar! How to implement #RequestMapping custom properties - That gives more details about what is going on, and how to have method level annotations (this example skips that and only defines class level annotations)
I have also written up some notes on this here: http://automateddeveloper.blogspot.co.uk/2014/12/spring-mvc-custom-routing-conditions.html
Implement AuthenticationSuccessHandler onAuthenticationSuccess redirect to specific controller based on the User Role.
I am storing objects in my database as JSON strings. I want to make a REST service that exposes these strings. When I write my methods however, the strings I get back have their quotes escaped. For example, I have included a method that returns a String,
#RequestMapping(value = "test", method = RequestMethod.GET)
public #ResponseBody
String getTest() {
return "{\"a\":1, \"b\":\"foo\"}";
}
but when I call this method in the browser I get a back "{\"a\":1, \"b\":\"foo\"}" when what I really want to happen is {"a": 1, "b": "foo"}. I think "String" as the return type is likely the problem, but what else can I do? A wrapper class does the same thing:
{
"value" : "{\"a\":1, \"b\":\"foo\"}"
}
I could serialize it and then return the object, but that seems a bit ridiculous.
Here is a possibly the relevant portion of my configuration file:
#Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
super.configureMessageConverters(converters);
converters.add(mappingJacksonHttpMessageConverter());
}
#Bean
MappingJacksonHttpMessageConverter mappingJacksonHttpMessageConverter() {
MappingJacksonHttpMessageConverter mappingJacksonHttpMessageConverter = new MappingJacksonHttpMessageConverter();
ObjectMapper objectMapper = new ObjectMapper();
objectMapper.setSerializationInclusion(JsonSerialize.Inclusion.NON_NULL);
mappingJacksonHttpMessageConverter.setObjectMapper(objectMapper);
mappingJacksonHttpMessageConverter.setPrettyPrint(true);
return mappingJacksonHttpMessageConverter;
}
Thanks
EDIT: as was suggested below, it seems the string is being double encoded. Commenting out the 2 classes in my configuration fixes this issue. However, I still have other places where I want to return Objects and would like to keep those running through that common serializing bean that I know where to configure. So I see my options as:
a) Do all the serializing myself. All methods return Strings, and those that are already JSON return themselves, and those that are objects all return JSONUtil.toJson(object). I don't love this approach, but I know it will work.
b) Use a wrapper class that looks kind of like:
public static class Wrapper {
#JsonRawValue
private final String value;
}
This leads to an awkward "value" at the front though that has no real meaning.
Basically what I want is #JsonRawValue, but to have it work on RequestMapping methods instead of properties.
Thoughts? Opinions? Other suggestions?
This works with Jackson 2 (at least):
#Controller
public class YourController {
#RequestMapping(..)
public #ResponseBody Json get() {
return new Json("{ \"attr\" : \"value\" }");
}
}
class Json {
private final String value;
public Json(String value) {
this.value = value;
}
#JsonValue
#JsonRawValue
public String value() {
return value;
}
}
Not particularly pretty but works. I only wish Spring supported this:
#RequestMapping(..)
public #JsonRawValue #ResponseBody String get() {
// ...
}
I guess what you want is producing a response with content-type application/json. In your case, when you have the json-data as a raw string, do the following:
In your controller add produces="application/json" to your #RequestMapping attribute:
#RequestMapping(value = "test", method = RequestMethod.GET, produces="application/json")
public #ResponseBody
String getTest() {
return "{\"a\":1, \"b\":\"foo\"}";
}
Then you have to configure the StringHttpMessageConverter to accept the application/json media-type.
With Java-config:
#Override
public void configureMessageConverters(
List<HttpMessageConverter<?>> converters) {
StringHttpMessageConverter stringConverter = new StringHttpMessageConverter(
Charset.forName("UTF-8"));
stringConverter.setSupportedMediaTypes(Arrays.asList( //
MediaType.TEXT_PLAIN, //
MediaType.TEXT_HTML, //
MediaType.APPLICATION_JSON));
converters.add(stringConverter);
}
With XML-config:
<bean class = "org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
<property name="messageConverters">
<array>
<bean class = "org.springframework.http.converter.StringHttpMessageConverter">
<property name="supportedMediaTypes" value="application/json; charset=UTF-8" />
</bean>
</array>
</property>
</bean>
I used this:
#RequestMapping(..)
#ResponseBody
public JsonNode myGetRequest(){
...
//rawJsonString is the raw Json that we want to proxy back to the client
return objectMapper.readTree(rawJsonString);
}
And the Jackson converter knew how to transform the JsonNode into plain Json.
If you want to convert JSON String to JSON object in your browser, keep string convertor before Jackson convertor.
Follow this link for complete example. It works with custom converter configuration plus spring validation.
It Works
converters.add(stringConverter());
converters.add(mappingJackson2HttpMessageConverter());
super.configureMessageConverters(converters);
It Doesn't
converters.add(mappingJackson2HttpMessageConverter());
converters.add(stringConverter());
super.configureMessageConverters(converters);
In my case, I wanted the response type to be determined by a request parameter, so had to specify the content type in the code, e.g.:
#RequestMapping("/myurl")
public void radiusSearch(#RequestParam responseType, HttpServletResponse response) throws IOException {
String jsonResponse = makeSomeJson();
response.setContentType(responseType);
try {
response.getOutputStream().write(jsonResponse.getBytes());
} finally {
response.getOutputStream().close();
}
}
Today we had the same issue and solved it with multiple converters. Now every String will treated as a string and every other Object will get serialised by Jackson. This allows to serialise manually (by returning String) or automatically (by returning something else) in Spring controllers.
#Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
converters.add(stringConverter());
converters.add(mappingJackson2HttpMessageConverter());
super.configureMessageConverters(converters);
}
#Bean
public StringHttpMessageConverter stringConverter() {
final StringHttpMessageConverter stringConverter = new StringHttpMessageConverter(UTF_8);
stringConverter.setSupportedMediaTypes(Arrays.asList(
MediaType.TEXT_PLAIN,
MediaType.TEXT_HTML,
MediaType.APPLICATION_JSON));
return stringConverter;
}
#Bean
public GenericHttpMessageConverter<Object> mappingJackson2HttpMessageConverter() {
final ObjectMapper objectMapper = objectMapperBuilder().build();
final MappingJackson2HttpMessageConverter converter = new MappingJackson2HttpMessageConverter(objectMapper);
return converter;
}
The \" means the character " is being escaped, which is standard. If it's being printed like that, you're probably double-serializing the object.
I know this is an old question, but I was just dealing with the opposite problem myself (I was returning a String and WANTED it to get converted to JSON). In your case, it sounds like you simply want to have your String treated as a plain string and not have any sort of JSON conversion done on it as you already have JSON.
So in your case you don't want to use the MappingJacksonHttpMessageConverter (or the MappingJackson2HttpMessageConverter if you're now using Jackson2). You want no conversions done at all, and that converter converts Java objects to/from JSON. So instead you should just use the plain StringHttpMessageConverter. You can do that by changing your setup method like this:
#Override
public void configureMessageConverters(List<HttpMessageConverter<?>> converters) {
converters.add(new StringHttpMessageConverter());
}
This converter is applicable to */* types (the document is incorrect which says text/*, I found out the hard way in the debugger). So whether your content type is application/json or not, either way Spring won't mess with your Strings if you use this converter.
The solution to your problem is, this works perfectly without changing any configurations
import com.fasterxml.jackson.databind.JsonNode;
import com.github.fge.jackson.JsonLoader;
JsonNode getTest() {
return JsonLoader.fromString("{\"a\":1, \"b\":\"foo\"}");
}
I'm pretty new to MVVM light world, and after searches I can't find what I want to do.
My WP7 application contains a pivot, each pivot item content is View1 and viewmodel is VM1.
When loading my application, I'd like to create every pivot item with the same view and view model but with different parameter.
example :
PivotItem 1 -> send param "car" to the view model
PivotItem 2 -> send param "truck" to the view model, etc.
Google told me to use messaging but if I send 2 messages from my MainViewModel, both PivotItem1 and PivotItem2 ViewModel will receive these messages.
Am I wrong with this approach ?
Is there another solution to succeed ?
Thank you in advance for your answer.
PS : be indulgent, english is not my native language, don't hesitate to ask for further information.
Regards,
Aymeric Lagier
To seperate the messages use the second constructor signature whereby you can pass a token. This token can be anything but I generally use an enum to store all my message types within the system.
Create a static class in a common library and reference this in all projects where you need to send or receive messages.
The following code hopefully shows this approach, notice I am sending a string as a value within the message but this can be anything, even a complex object such as one of your business objects.
namespace MyProject.Common
{
public static class AppMessages
{
enum MessageTypes
{
ViewmodelA,
ViewmodelB
}
public static class ViewModelAUpdate
{
public static void Send(string value)
{
Messenger.Default.Send(value, MessageTypes.ViewmodelA);
}
public static void Register(object recipient, Action<string> action)
{
Messenger.Default.Register(recipient, MessageTypes.ViewmodelA, action);
}
}
public static class ViewModelBUpdate
{
public static void Send(string value)
{
Messenger.Default.Send(value, MessageTypes.ViewmodelB);
}
public static void Register(object recipient, Action<string> action)
{
Messenger.Default.Register(recipient, MessageTypes.ViewmodelB, action);
}
}
}
}
How about using a method to set the message you want to receive. (this could be done as a parameter in the constructor or a property as well)
public void RegisterForAppMessage(AppMessages.MessageTypes messageType)
{
switch (messageType)
{
case AppMessages.MessageTypes.PivotViewItem1Message:
AppMessages.PivotViewItem1Message.Register(this,DoSomethingWhenIRecievePivotViewItem1Messages)
break;
case AppMessages.MessageTypes.PivotViewItem2Message:
AppMessages.PivotViewItem2Message.Register(this,DoSomethingWhenIRecievePivotViewItem2Messages)
break;
}
}
private void DoSomethingWhenIRecievePivotViewItem2Messages(string obj)
{
// TODO: Implement this method
throw new NotImplementedException();
}
private void DoSomethingWhenIRecievePivotViewItem1Messages(string obj)
{
// TODO: Implement this method
throw new NotImplementedException();
}
Messaging sounds a bit heavy for this purpose. Could you simply inject a parameter into your ViewModel. If you already have MVVMLight you also have support for SimpleIOC. Maybe let the view locate its ViewModel when the view is resolved and there decide which parameter to use on the view model?
You can see an example of it here
I am in the middle of converting my controllers to annotated style controllers in spring mvc.
Basically I do this in the old style controller simpleformcontroller.
protected Map referenceData(HttpServletRequest request) throws Exception
{
Map referenceData = new HashMap();
List<ItemVo> lstItem1 = eqrManager
.searchAllEqptCondQualItems("A1", "BOXES");
List<ItemVo> lstItem2 = eqrManager
.searchAllEqptFullQualItems("A2", "CANNED_GOODS");
referenceData.put("BOX_ITEMS", lstItem1);
referenceData.put("CANNED_ITEMS", lstItem2);
return referenceData;
}
In the annotated, I do something like this:
#ModelAttribute("BOX_ITEMS")
public List<ItemVo> populateCondEQRItems() {
List<ItemVo> lstCondQual = eqrManager
.searchAllEqptCondQualItems("A1", "BOXES");
return lstCondQual;
}
#ModelAttribute("CANNED_ITEMS")
public List<ItemVo> populateFullEQRItems() {
List<ItemVo> lstFullQual = eqrManager
.searchAllEqptFullQualItems("A2", "CANNED_GOODS");
return lstFullQual;
}
My question is, is there a way to return all attributes in just a single method and not
having to create multiple #ModelAttribute? In my case, I need to annotate 2 method? What if I need
3, should I create 3 annotated methods also?
The rule is clear
If you need more than one model attribute, take model as a input argument
#RequestMapping(method=RequestMethod.GET)
public void setUp(Model model) {
model.addAttribute("CANNED_ITEMS", eqrManager.searchAllEqptFullQualItems("A2", "CANNED_GOODS"))
.addAttribute("BOX_ITEMS", eqrManager.searchAllEqptCondQualItems("A1", "BOXES"));
}
Good lucky!
I cannot get it clearly
Ok! I was telling that #ModelAttribute can be put at Method level as well as Method Parameter level. And it behaves differently depends on where you've put it.
#ModelAttribute(user)
public void preRender(Model model) {
/* this method will be invoked before resolving #ModelAttribute Method Parameter i.e. before invoking render/processCreate method */
/* codes are available to CreateUser.jsp if render request comes */
/* codes are available to CreateUser.jsp if validation fails */
model.addAttribute("countryCodes", I18Nservice.getCountryISOCodes());
model.addAttribute("languageCodes", I18Nservice.getLanguageISOCodes());
}
public String renderCreate(#ModelAttribute(value="user") User user) {
return "/user/create";
}
#Override
public String processCreate(#ModelAttribute(value="user") User user, BindingResult result) {
if(result.hasErrors() {
return "/user/create";
}
securityService.createUser(user);
return "/user/detail/user.getId()";
}
If you are new in Spring MVC 3 arena:
read Web MVC framework
Check #RequestMapping JavaDoc
And play with Petcinic & mvc-showcase