I am developing a spring boot application, using boot v 1.2.5, using thymeleaf as the view technology
In my Mvc Configuration file
#Configuration
public class MVCConfig extends WebMvcConfigurerAdapter {
#Override
public void addViewControllers(ViewControllerRegistry registry) {
registry.addViewController("/message").setViewName("message");
registry.addViewController("/error").setViewName("errors/error");
registry.addViewController("/login").setViewName("authentication/login");
}
The problem is that the first and last mapping is working fine, but the middle one "error" is not working at all !!
I am using the same rules as the other two templates, same prefix, same directory structure, so it is supposed to work like the other two !!
But, when i point my browser to /error, spring boot show the fallback error page saying that there is no mapping for /error
when i change it to:
registry.addViewController("/error").setViewName("errors/error");
it works fine for /errors
Spring boot documentation states about the /error handling:
"For browser clients there is a ‘whitelabel’ error view that renders the same data in HTML format (to customize it just add a View that resolves to ‘error’)."
so, it says to add a view that resolve to error, that's what i did, but it does not work !!
so, what is the problem? why /error does not work?
You've added a view controller for /error, not a view. This is then being overridden by Boot's own controller with a /error mapping. As a result, you get the default error page.
All you need to do is to provide an error view. As you're using Thymeleaf, you can do so by creating a file named src/main/resources/templates/error.html.
Related
How can I get Spring Boot and Thymeleaf to automatically find and map template files to be processed when accessed by the browser?
src/main/resources/templates/index.xhtml
src/main/resources/templates/bar.xhtml
src/main/resources/application.properties contains spring.thymeleaf.suffix=.xhtml
FooController.java contains #RequestMapping("/foo") and a #PostMapping method that returns bar
If I enter http://localhost:8080/ in the browser, Thymeleaf processes and displays the index.xhtml page with no extra configuration needed. But http://localhost:8080/index, http://localhost:8080/index.xhtml, and http://localhost:8080/index.html all result in 404 Not Found.
My index view does a POST to foo; FooController is activated and returns bar; and Thymeleaf processes and shows bar.xhtml, even though bar.xhtml isn't mapped anywhere in the configuration. Yet accessing http://localhost:8080/bar, http://localhost:8080/bar.xhtml, and http://localhost:8080/bar.html in a browser all result in 404 Not Found.
Why does GET http://localhost:8080/ process the index.xhtml template, but GET http://localhost:8080/index does not?
How can Thymleaf use bar as a view, but I cannot access http://localhost:8080/bar directly?
How can I configure Thymeleaf so that I can add src/main/resources/templates/example.xhtml and have it processed automatically as a template that I can access via http://localhost:8080/example in the browser, with no explicit configuration specifically for the example.xhtml file?
If I absolutely have to configure controllers (see my answer below), is there a way that I can at least do this in some declarative file, outside of my code?
As noted in Spring in Action, Fifth Edition, I can do something like this in a #Configuration class that implements WebMvcConfigurer
#Override
public void addViewControllers(final ViewControllerRegistry registry) {
registry.addViewController("/bar");
}
That will allow me to process bar.xhtml automatically. (I presume there is some default configuration registry.addViewController("/").setViewName("index"), which is why my index.xhtml file is getting processed by accessing the root path.
And I can even use the following to automatically pick up any template:
#Override
public void addViewControllers(final ViewControllerRegistry registry) {
registry.addViewController("/**");
}
Unfortunately this removes the mapping from / to /index, and also prevents accessing any static resources from src/main/resources. I'm not sure how to tell Thymeleaf to use a template if it can, and fall back to a static file if not.
Related question:
Spring Boot Remove Whitelabel Error Page
For my case,
I disabled whitelabel by setting whitelabel.enabled = false, and I also exclude ErrorMvcAutoConfiguration. It worked in regular spring boot service. But I deployed the same service on PCF cloud foundry, then spring still want to redirect error to /error page.
Any help and suggestion is welcome.
Edit:
I added exclude annotation on Application, then it works on PCF.
Previously I added exclude configuration in application.yml, then it didn't work on PCF
You need to create a separate endpoint /error and then handle it in the method. I would suggest you to maintain a separate controller infact. My code would look something like this
#RestController
#RequestMapping(path = "/error")
public class ErrorController {
#ApiOperation(value = "Error Page", notes = "Error Page")
#GetMapping
public String error() {
return "Some Error Occurred and I will Graciously show the Error"
}
}
It turns out circuit breaker service set exclusion property first, than local application.yml didn't take effect. If I add exclusion property in repo, then it take preference.
I feel this is kind of spring bug, since exclusion is list, it should include all items, instead of taking the first configuration only.
In Spring Boot, what is the purpose of server.error.path property in application.properties file?
The documentation just says:
Path of the error controller
But I want a clear description of this property with an example.
server.error.path - used as part of url for error pages.
site.getBaseUrl() + "/error"
For example some error happen on server side and you decide redirect user to error page like this:
https://docs.aws.amazon.com/AmazonCloudFront/latest/DeveloperGuide/images/custom-error-page-aws-404-example.png
Code example of error controller you can find here:
https://www.logicbig.com/tutorials/spring-framework/spring-boot/implementing-error-controller.html
You can use this property in #RequestMapping("/error"). But instead of "/error" you can use "${server.error.path}"
UPDATE:
Also, Spring Boot BasicErrorController use server.error.path property
Property server.error.path in spring boot application used to define an error path while dealing with custom error handler. In Spring we create custom error handler using functional interface ErrorController, ths interface has a String type method getErrorPath which helps us to return the error page path(our error page as view).
But from Spring 2.3.0 this getErrorPath() method has been deprecated and replaced with server.error.path to manage the error path.
e.g. server.error.path=/error
For more detail about interface ErrorController, please refer Spring doc for ErrorController
I am getting a HTTP 404 error when trying to serve index.html ( located under main/resources/static) from a spring boot app. However if I remove the Jersey based JAX-RS class from the project, then http://localhost:8080/index.html works fine.
The following is main class
#SpringBootApplication
public class BootWebApplication {
public static void main(String[] args) {
SpringApplication.run(BootWebApplication.class, args);
}
}
I am not sure if I am missing something here.
Thanks
The problem is the default setting of the Jersey servlet path, which defaults to /*. This hogs up all the requests, including request to the default servlet for static content. So the request is going to Jersey looking for the static content, and when it can't find the resource within the Jersey application, it will send out a 404.
You have a couple options around this:
Configure Jerse runtime as a filter (instead of as a servlet by default). See this post for how you can do that. Also with this option, you need to configure one of the ServletProperties to forward the 404s to the servlet container. You can use the property that configures Jersey to forward all request which results in a Jersey resource not being found, or the property that allows you to configure a regex pattern for requests to foward.
You can simply change the Jersey servlet pattern to something else other than the default. The easiest way to do that is to annotate your ResourceConfig subclass with #ApplicationPath("/root-path"). Or you can configure it in your application.properties - spring.jersey.applicationPath.
Is there a way to tell if Spring has loaded my #Controller?
I'm requesting a URL but I'm not hitting my controller and I can't figure out why
I'm loading controllers by doing a component scan
<context:component-scan base-package="com.example.app.web"/>
Other controllers in the same package as my failing controller are working fine.
My controller code is:
#Controller
#RequestMapping(value = "/app/administration/ecosystem")
public class AppEcosystemController {
#Autowired
EcosystemManagerService ecosystemManagerService;
#RequestMapping(value = "/Foo", method = RequestMethod.GET)
public String getEcosystem() {
/* Implementation */
}
The first thing I'd like to do is to be sure that this controller is getting picked up by the component scan.
Any suggestions?
Just enable logging for your application, you can find this information at INFO level
For example in my application I have a controller named UserController.
The following log4j.properties does the trick.
log4j.rootLogger=INFO, FILE
log4j.appender.FILE=org.apache.log4j.FileAppender
log4j.appender.FILE.File=../logs/rest-json.log
log4j.appender.FILE.layout=org.apache.log4j.PatternLayout
log4j.appender.FILE.layout.ConversionPattern=%d{ABSOLUTE} %5p %c{1}:%L - %m%n
I can see in the log that RequestMappingHandlerMapping mapped my controller (scroll all the way to the right).
07:28:36,255 INFO RequestMappingHandlerMapping:182 - Mapped "{[/rest/**/users/{id}],methods=[GET],params=[],headers=[],consumes=[],produces=[text/xml || application/json],custom=[]}" onto public org..domain.User org.ramanh.controller.UserController.getUser(java.lang.String)
07:28:36,255 INFO RequestMappingHandlerMapping:182 - Mapped "{[/rest/**/users],methods=[POST],params=[],headers=[],consumes=[],produces=[text/xml || application/json],custom=[]}" onto public void org..controller.UserController.addUser(org...domain.User)
If you are still unsure I would suggest adding a method annotated with #PostConstruct.
You could easily look up the message in the log or place a break point in this method.
#PostConstruct
protected void iamAlive(){
log.info(“Hello AppEcosystemController”)
}
If you find that your controller is initialized correctly but still the url is not accessible.I would test the following
You are getting 404 error - maybe you are not pointing to the correct
url (do not forget to add the application as prefix to the url)
You are getting 404 error - Dispatcher servlet mapping in web.xml doesn't meet
the url above
You are getting 403/401 – maybe you are using
spring security and it’s blocking the url
You are getting 406 – your
content type definition is conflicting with your request
You are getting 50x – something is buggy in your code
I made an ApplicationContextDumper. Add it into application context, it will dump all beans and their dependencies in the current context and parent contexts (if any) into log file when the application context initialization finishes. It also lists the beans which aren’t referenced.
It was inspired by this answer.
You could start out with enabling debug logging for Spring as outlined here.
I'd also recommend leveraging the MVC testing support, which you'll find in the spring-test jar. Details on how to use it can be found here and here.