(Explicit Binding) Customizing The Resolution Logic & Customizing The "Not Found" Behavior - php

To explicitly bind a parameter to a model and throwing a custom exception I have to (among other things) add the following to the RouteServiceProvider:
$router->model('parameter', 'App\Model', function () {
throw new CustomNotFoundException;
});
To customize the resolution logic of the explicit binding I have to add the following to the RouteServiceProvider:
$router->bind('parameter', function ($parameter) {
return App\Model::where('field', $parameter)->first();
});
My problem is that I need both but apparently can't. If I bind the parameter to the model and also customize the resolution logic it won't throw my CustomNotFoundException, instead it will throw the default ModelNotFoundException.
To clearly summarize my objective: I want to customize the resolution logic and throw a custom exception if it fails to find a record.
EDIT I have tried this as per a suggestion from #Maraboc:
$router->bind('parameter', function ($parameter) {
try {
return App\Model::where('field' => $parameter)->first();
} catch (Exception $e) {
throw new CustomNotFoundException;
}
});
This will still throw a ModelNotFoundException for a reason I'm not aware.

Try it like this :
$router->bind('parameter', function ($parameter) {
try {
return App\Model::where('field' => $parameter)->firstOrFail();
} catch (ModelNotFoundException $e) {
throw new CustomNotFoundException;
}
});
OR in the App\Exceptions\Handler add this to the render method :
if ($e instanceof ModelNotFoundException) {
throw new CustomNotFoundException;
}
And use Illuminate\Database\Eloquent\ModelNotFoundException as ModelNotFoundException;
OR an other workaround is to do like so :
$router->bind('parameter', function ($parameter) {
$model = App\Model::where('field' => $parameter)->first();
if ( ! $model) {
throw new CustomNotFoundException;
}
return $model;
});

Related

Laravel throw ValidationException but not hitting destroy method's catch block?

I am trying to return a custom exception message using Laravel's ValidationException class. I have it successfully working in the following example:
public function store(Request $request)
{
$this->validate($request, CurrencyValidatorArrays::$store);
try {
$this->currenciesInstance->createOrUpdateCurrency($request->all());
return redirect()->route('currencies.index')
->with('success', 'Successfully created currency');
} catch (Exception $e) {
return redirect()->route('currencies.create')
->with('error', $e->getMessage());
}
}
where the exception is thrown from within createOrUpdateCurrency()
if(Currency::where('position', $data['position'])->where('id', '!=', $id)->exists()) {
throw ValidationException::withMessages([
'error' => ['Position value is already taken']
]);
}
This then passes the exception message back to my view for display.
However, I am trying to implement this somewhere else when trying to delete a company I am checking that no users exist first:
public function destroy($id)
{
try {
$this->companiesInstance->deleteCompany($id);
return redirect()->route('companies.index')
->with('success', 'Successfully deleted company');
} catch (Exception $e) {
return redirect()->route('companies.index')
->with('error', $e->getMessage());
}
}
Inside of deleteCompany():
$company = Company::find($id);
if($company->users()->exists()){
throw ValidationException::withMessages([
'error' => ['Position value is already taken']
]);
}
For some reason this doesn't hit my catch block from the main destroy method,if I change the exception type to ValidationException from Exception I can access and see the exception object but not in the way I can in the Store() methods version. Any ideas what is going on here?
UPDATE:
So I have a some what of a workaround:
To get by the exception type issue I used:
catch (ValidationException | Exception $e) { ...
But that still does not help when accessing the exception messages as when it's of type ValidationException the default constructor validation message is returned from getMessage() and not my specified one.
PHP 7 handles exceptions a bit differently. You can read it here.
Coming back to your code, you have to try and catch object of Throwable instead of Exception.
try
{
// Code that may throw an Exception or Error.
}
catch (Throwable $t)
{
// Code that handles the error
}
Hope this helps.

Prevent laravel message to be displayed and redirect the user to custom page issue in Laravel 5

I would like to catch somehow the laravel error, warning message. I don't want to disable them from the config/app.php file. I am using monolog to log some information.
This is my piece of code:
public function view($id){
try {
$tag = Tags::find(12313); // tags is a model
}catch(Exception $error){
echo 'error'; exit();
$this->log->logMessage(Logger::ERROR, $error->getMessage());
return redirect()->route('admin.tags')->with(['msg' => 'Smth went wrong']);
}
}
$this->log is a class where I am using the monolog class to log information.
The fact is that right now , it doesn't go to the catch part . I don't get the error message. I'm getting this message from laravel:
Trying to get property of non-object (View: ......
I intentionally put the number 12313 there to see if it is working or not. And for some reason is not working and I am not redirected . The idea, if something happened I want to redirect the user to a specific page with a general error message. How can I achieve that ?
You can do it in laravel .You can handle erors in App\Exceptions\Handler class
public function render($request, Exception $exception)
{
if($exception instanceof NotFoundHttpException)
{
return response()->view('errors.404', [], 404);
}
if ($exception instanceof MethodNotAllowedHttpException)
{
return response()->view('errors.405', [], 405);
}
if($exception instanceof MethodNotAllowedHttpException)
{
return response()->view('errors.404', [], 405);
}
return parent::render($request, $exception);
}
find() method doesn't throw an exception if the record is not found. So do this instead:
public function view($id)
{
$tag = Tags::find(12313); // tags is a model
if (is_null($tag)) {
$this->log->logMessage(Logger::ERROR, $error->getMessage());
return redirect()->route('admin.tags')->with(['msg' => 'Smth went wrong']);
}
}
Or use findOrFail() which will throw an exception if specified record is not found.
Sometimes you may wish to throw an exception if a model is not found. This is particularly useful in routes or controllers. The findOrFail and firstOrFail methods will retrieve the first result of the query; however, if no result is found, a Illuminate\Database\Eloquent\ModelNotFoundException will be thrown

How to reach the exception block

So I am messing around with symfony router component and I created a small wrapper.
One thing that came up was how do I get a request to throw a 500 in unit tests? The method in question is:
public function processRoutes(Request $request) {
try {
$request->attributes->add($this->_matcher->match($request->getPathInfo()));
return call_user_func_array($request->attributes->get('callback'), array($request));
} catch (ResourceNotFoundException $e) {
return new RedirectResponse('/404', 302);
} catch (Exception $e) {
return new RedirectResponse('/500', 302);
}
}
And the test in question is:
public function testFiveHundred() {
$router = new Router();
$router->get('/foo/{bar}', 'foo', function($request){
return 'hello ' . $request->attributes->get('bar');
});
$response = $router->processRoutes(Request::create('/foo/bar', 'GET'));
$this->assertEquals(500, $response->getStatusCode());
}
Right now the test will fail because we are defined and the status code will be 200. Is there something special I can do to the Request object I create, to make it throw a 500?
I think you got several options here you can play with:
Decide that a specific path will always throw an exception.
This will force you to make some changes in your code.
public function processRoutes(Request $request) {
...
if ($request->getRequestUri() == '/path/that/throws/exception') {
throw Exception('Forced to throw exception by URL');
}
...
}
public function testFiveHundred() {
...
$response = $router->processRoutes(Request::create('/path/that/throws/exception', 'GET'));
...
}
Make a DummyRequest object that will extends your original Request class and make sure this object will raise an Exception (for example - you know for sure that you use the getPathInfo(), so you can use this).
class DummyRequest extends Request {
public function getPathInfo() {
throw new Exception('This dummy request object should only throw an exception so we can test our routes for problems');
}
}
public function testFiveHundred() {
...
$dummyRequest = new DummyRequest();
$response = $router->processRoutes($dummyRequest);
...
}
Since the function getRequestUri of our $dummyRequest throws an exception, your call to $router->processRoutes will have our dummy to throw that exception.
This is a general idea, you would probably need to play a bit with the namespaces and the functions there (I didn't test it, however this should work).

Set http code for Symfony constraint validation failure

Shortly: how can you set a specific http error code, instead of a generic 500, when a constraint fails on entity save?
Details
I'm using Symfony custom constraint #UniqueEntity (http://symfony.com/doc/current/reference/constraints/UniqueEntity.html) to assert that some data is not duplicated when saving an entity.
If this constraint check results in a violation, I get a 500 http code, while others may be more appropriate, e.g. 409 - Conflict (https://httpstatuses.com/409).
I can't seem to find any documentation on how to override the validation response.
Thank you in advance for any suggestion.
Maybe you could create a Listener to the event : kernel.exception
And then you will have something like :
<?php
public function onKernelException(GetResponseForExceptionEvent $event)
{
$e = $event->getException();
if ($e instanceof NameOfTheException) {
// logic here
return (new Response())
->setStatusCode(409)
;
}
}
Just catch exception in controller:
public function saveAction()
{
try {
$entity = new Entity('duplicate name');
$this->entityManager->persist($entity);
$this->entityManager->flush();
return new Response();
} catch(UniqueConstraintViolationException $e) {
return new Response('Entity with same name already exists', Response::HTTP_CONFLICT);
} catch (\Exception $e) {
return new Response('Internal error', Response::HTTP_INTERNAL_SERVER_ERROR);
}
}

Laravel : Handle findOrFail( ) on Fail

I am looking for something which can be like findOrDo(). Like do this when data not found. Something could be like
Model::findOrDo($id,function(){
return "Data not found";
});
Is there any similar thing in laravel that I can do this elegantly and beautifully ?
*I tried googling but could not find one
use Illuminate\Database\Eloquent\ModelNotFoundException;
// Will return a ModelNotFoundException if no user with that id
try
{
$user = User::findOrFail($id);
}
// catch(Exception $e) catch any exception
catch(ModelNotFoundException $e)
{
dd(get_class_methods($e)); // lists all available methods for exception object
dd($e);
}
Another option is to modify the default Laravel Exception Handler, found in app/Exceptions/Handler.php on the render() function I made this change:
public function render($request, Exception $e)
{
if(get_class($e) == "Illuminate\Database\Eloquent\ModelNotFoundException") {
return (new Response('Model not found', 400));
}
return parent::render($request, $e);
}
That way instead of getting a 500, I send back a 400 with a custom message without having to do a try catch on every single findOrFail()
By default, when you use an Eloquent model’s findOrFail in a Laravel 5 application and it fails, it returns the following error:
ModelNotFoundException in Builder.php line 129:
'No query results for model [App\Model]'.
So to catch the exception and display a custom 404 page with your error message like "Ooops"....
Open up the app/Exceptions/Handler.php file, and add the code shown below to the top of the render function:
public function render($request, Exception $e)
{
if ($e instanceof \Illuminate\Database\Eloquent\ModelNotFoundException)
{
abort(404, 'Oops...Not found!');
}
return parent::render($request, $e);
}
Source: https://selftaughtcoders.com/from-idea-to-launch/lesson-16/laravel-5-findorfail-modelnotfoundexception-show-404-error-page/
An alternative process could be to evaluate a collection instead. So,
$modelCollection = Model::where('id', $id)->get();
if(!$modelCollection->isEmpty()) {
doActions();
}
I agree it isn't as elegant, a one-liner or as case specific as you or I might like, but aside from writing a try catch statement every time, it's a nice alternative.
as of Laravel v5.7, you can do this (the retrieving single model variation of #thewizardguy answer)
// $model will be null if not found
$model = Model::where('id', $id)->first();
if($model) {
doActions();
}
A little later for the party, from laravel 5.4 onward, Eloquent Builder supports macros. So, I would write a macro (in a separate provider) like follows.
Builder::macro('firstOrElse', function($callback) {
$res = $this->get();
if($res->isEmpty()) {
$callback->call($this);
}
return $res->first();
});
I can then do a retrieval as follows.
$firstMatchingStudent = DB::table('students')->where('name', $name)
->firstOrElse(function() use ($name) {
throw new ModelNotFoundException("No student was found by the name $name");
});
This will assign the first object of the result set if it is not empty, otherwise will adapt the behaviour I pass into the macro as a closure (throw Illuminate\Database\Eloquent\ModelNotFoundException in this case).
For the case of a model also this would work, except that models always return the builder instance.
In the newer version of Laravel (for me in v9.41.0) we have the Register method in Handler.php ,
so for customize the exception of findOrFail method we have to add this code to that file:
$this->renderable(function (NotFoundHttpException $exception, $request) {
if ($request->expectsJson()) {
//when you need it for API
return response()->json([
'responseCode'=> 404,
'message' => "Item not found",
'errorCode' => 1000404
], 404 );
}else{
return view("some-custom-view");
}
});
I needed NotFoundHttpException which has the namespace below (you can use any other Exception for customization) and have to be used out of the class:
use Symfony\Component\HttpKernel\Exception\NotFoundHttpException;

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