In my front end application, I have to handle the error response of the HTTP REST call.
Front end:
restservice.check().subscribe(
response => {
if (response != null) {
},
error => {
if (error instanceof Error) {
}}
});
Controller.java
public ResponseEntity updateEstablishment
{
return new ResponseEntity<>(obj, HttpStatus.OK);
}
How can I return an instance of Error here.
REST services should catch and handle internal exception. And should return meaningful error code and message back to client. Please find below link to best way to handle exception in REST
https://www.baeldung.com/rest-api-error-handling-best-practices
Related
I'm currently building a single page application based on Laravel and VueJS.
Is there any better way then mine to handle errors with axios?
This is how I currently do it when a user clicks on login button:
VueTemplae:
methods : {
authenticateUser() {
axios.post('/api/login', this.form).then(() => {
this.$router.push({name : 'home'});
}).catch((error) => {
this.error = error.response.data.message;
});
}
}
Api route:
public function login() {
try {
// do validation
} catch(Exception) {
// validation failed
throw new Exception('login.failed');
}
// manually authentication
if(Auth::attempt(request()->only('email', 'password'))) {
return response()->json(Auth::user(), 200);
}
// something else went wrong
throw new Exception('login.failed');
}
Unfortunately, throwing an exception always prints an internal server error into the console.
If I return something else than an exception, axios always executes then().
Is there any way to prevent this or a better way to handle axios responses?
Thank you!
Your API needs to return a response with a 4XX status code in order for the catch block to fire in your Vue component.
Example:
After you catch the error on the API side, send a response with status code 400 Bad Request. It will be formatted similarly to your successful login response, but with an error message and 400 status code instead of 200.
I was browsing abp's blogging module. There is a code like below in post repo.
https://github.com/abpframework/abp/blob/dev/modules/blogging/src/Volo.Blogging.EntityFrameworkCore/Volo/Blogging/Posts/EfCorePostRepository.cs
public async Task<Post> GetPostByUrl(Guid blogId, string url)
{
var post = await DbSet.FirstOrDefaultAsync(p => p.BlogId == blogId && p.Url == url);
if (post == null)
{
throw new EntityNotFoundException(typeof(Post), nameof(post));
}
return post;
}
I'm testing module and im getting error like blow if there is no entity.
An unhandled exception occurred while processing the request.
EntityNotFoundException: There is no such an entity. Entity type:
Volo.Blogging.Posts.Post, id: post
Volo.Blogging.Posts.EfCorePostRepository.GetPostByUrl(Guid blogId,
string url) in EfCorePostRepository.cs, line 35
It is normal to get this exception if there is no entity, but how to show 404 page or message like there is no record to user? I tried to throw UserFriendlyException but still getting and error page.
Need to perform some asynchronous processing in a Rest service without holding up the server's Http threads .
I think DeferredResult would be a good option.
However when I am trying to ensure my callback on error gets called - am not able to do so .
Here is a naive attempt on my part:
#GetMapping("/getErrorResults")
public DeferredResult<ResponseEntity<?>> getDeferredResultsError(){
final String METHOD_NAME = "getDeferredResultsError";
logger.info("START : {}",METHOD_NAME);
DeferredResult<ResponseEntity<?>> deferredOutput = new DeferredResult<>();
ForkJoinPool.commonPool().submit(() -> {
logger.info("processing in separate thread");
int age = 0;
try {
age = age / 0;
}catch(Exception e) {
logger.error("we got some error");
logger.error(e);
throw e;
}
logger.info("after try catch block");
});
deferredOutput.onError((Throwable t) -> {
logger.error("<<< HERE !!! >>>");
deferredOutput.setErrorResult(
ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
.body(t.getMessage()));
});
logger.info("done");
return deferredOutput;
}
When I call this Rest endpoint from Postman - I can see in server logs the arithmetic exception by zero but dont see the 'onError' getting invoked.
After some time get a response in Postman as follows:
{
"timestamp": "2019-07-30T09:57:16.854+0000",
"status": 503,
"error": "Service Unavailable",
"message": "No message available",
"path": "/dfr/getErrorResults"
}
So my question is how does the 'onError' get invoked ?
You need to pass the DeferredResult object to the asynchronous operation so you could update it in case of success or failure:
#GetMapping(value = "/getErrorResults")
public DeferredResult<ResponseEntity<String>> getDeferredResultsError() {
DeferredResult<ResponseEntity<String>> deferredResult = new DeferredResult<>();
ForkJoinPool.commonPool().submit(() -> {
System.out.println("Processing...");
int age = 0;
try {
age = age / 0;
deferredResult.setResult(ResponseEntity.ok("completed"));
}catch(Exception e) {
System.out.println("Failed to process: " + e.getMessage());
deferredResult.setErrorResult(
ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
.body(e.getMessage()));
}
});
return deferredResult;
}
In the code you posted, you returned the DeferredResult object without passing it to the asynchronous operation. So after your return it, SpringMVC holds the client connection and wait until the DeferredResult object will be assigned with some kind of result. But in your case, the DeferredResult is not held by the asynchronous operation and will never updated so you get "Service Unavailable".
Here you can find working (light) project example.
I have some web-enabled actions that are exposed through API Connect in IBM Cloud Serverless Functions.
Some of my actions use request-promises to call external REST services and I need to be able to catch an error and respond with an appropriate status-code to the caller.
Since the actions are web-enabled, the documentation indicates that I can use an annotated JSON to set the headers, status-code and body of the response. But it seems that, seems the API expects to always get a Content-Type=application/json, the response processor is failing to understand my annotations in the case of an error.
I tried the following without success:
let rp = require('request-promise');
function main(params){
//setup options
return rp(options).then(
res => {
return res;
}
).catch(
err => {
return { error: { statusCode:err.statusCode } }
}
);
}
Another variation:
let rp = require('request-promise');
function main(params){
//setup options
return rp(options).then(
res => {
return res;
}
).catch(
err => {
return { statusCode:err.statusCode }
}
);
}
The problem is that the status-code I always get is 200... I also tried to change the runtime to node8.0 without success.
Thanks!
I found the answer myself :)
In order to get the status-code and headers, one must set the field Response Content Type to `Use "Content-Type" header from action", while setting up the mapping between the API call and the action....
I have zuul filter implementation with route config
related:
path: /api/search/related/**
url: http://abc.xyz.neverhit.this.URl
and run implementation
#Override
public Object run() {
RequestContext context = getCurrentContext();
HttpServletRequest request = context.getRequest();
UriComponents uri = UriComponentsBuilder.fromHttpUrl(recommendationsServiceHostname)
.path("/recommendations/related")
.query(request.getQueryString()).build();
if (shouldRouteToRecommendationsService(request, uri)) {
logger.info("Calling proxy service");
try {
context.setRouteHost(new URL(uri.toString()));
} catch (MalformedURLException ex) {
logger.error("MalformedURLException for URL:" + uri.toString());
}
}
else
{
//Something here or Solution that should handle a request like a filter is not present.
}
return null;
}
Its working fine for if part and sending the request to proxy service. Problem is for else part.
What I am looking for is in else scenario it should behave like filter never existed and it should handle request it was handling early executing API call from local code.
Any hack or proper solution for this one ?