Should a class be able to hold an instance of itself? - php

I am currently busy with a PSR-7 project with responses and requests.
Currently we are setting up an application in our index.php by doing something like:
$app = new Application();
$app->loadConfiguration(
'../config/global.yml',
);
// Should return the response?
$app->run((new ServerRequestFactory())->createServerRequestFromGlobals());
Here the run method also calls an emit method that is responsible for sending the headers and printing the body of the response.
The request and respons are now linked together in one call which makes it hard to test since you don't want to send the response with the headers straight to PHPUnit.
I have removed the emit call in the chain of the run method and added this to the index after the run method call:
// Send the response.
$app->send();
This way they are decoupled but the downside is I now have to hold a instance of my response in a response property inside my Application.php($app) class.
I want to move the response instance to the response class itself but my co-workers thinks a class should never hold an instance of itself. Yet when I look at frameworks this happens quite a lot. Is he right about this?
What arguments can I make to decouple my request and response besides easier testing?
I am pretty new to unit testing, one of the arguments I have already heard is that I should not test the full application anyways but rather separate components and therefore should not be worried about de-coupling the request and response.

Related

How can I do a partial integration test (phpunit)?

I am working on an extension (app) of nextcloud (which is based on Symfony). I have a helper class to extract data from the request that is passed by the HTTP server to PHP. A much-reduced one could be something like this (to get the point here):
<?php
namespace OCA\Cookbook\Helpers;
class RequestHelper {
public function getJson(){
if($_SERVER['Request_Method' === 'PUT'){ // Notice the typos, should be REQUEST_METHOD
$raw = file_get_content('php://input');
return json_decode($raw, true);
} else { /* ... */ }
}
}
Now I want to test this code. Of course, I can do some unit testing and mock the $_SERVER variable. Potentially I would have to extarct the file_get_content into its own method and do a partial mock of that class. I get that. The question is: How much is this test worth?
If I just mimick the behavior of that class (white box testing) in my test cases I might even copy and paste the typo I intentionally included here. As this code is an MWE, real code might get more complex and should be compatible with different HTTP servers (like apache, nginx, lighttpd etc).
So, ideally, I would like to do some automated testing in my CI process that uses a real HTTP server with different versions/programs to see if the integration is working correctly. Welcome to integration testing.
I could now run the nextcloud server with my extension included in a test environment and test some real API endpoints. This is more like functional testing as everything is tested (server, NC core, my code and the DB):
phpunit <---> HTTP server <---> nextcloud core <---> extension code <---> DB
^
|
+--> RequestHelper
Apart from speed, I have to carefully take into account to test all possible paths through the class RequestHelper (device under test, DUT). This seems a bit brittle to me in the long run.
All I could think of is adding a simple endpoint only for testing the functionality of the DUT, something like a pure echo endpoint or so. For the production use, I do not feel comfortable having something like this laying around.
I am therefore looking for an integration test with a partial mock of the app (mocking the business logic + DB) to test the route between the HTTP server and my DUT. In other words, I want to test the integration of the HTTP server, nextcloud core, my controller, and the DUT above without any business logic of my app.
How can I realize such test cases?
Edit 1
As I found from the comments the problem statement was not so obviously clear, I try to explain a bit at the cost of the simplicity of the use-case.
There is the nextcloud core that can be seen as a framework from the perspective of the app. So, there can be controller classes that can be used as targets for URL/API endpoints. So for example /apps/cookbook/recipe/15 with a GET method will fetch the recipe with id 15. Similarly, with PUT there can be a JSON uploaded to update that recipe.
So, inside the corresponding controller the structure is like
class RecipeController extends Controller {
/* Here the PUT /apps/cookbook/recipe/{id} endpoint will be routed */
public function update($id){
$json = $this->requestHelper->getJson(); // Call to helper
// Here comes the business logic
// aka calls to other classes that will save and update the state
// and perform the DB operation
$this->service->doSomething($json);
// Return an answer if the operation terminated successfully
return JsonResponse(['state'=>'ok'], 200);
}
}
I want to test the getJson() method against different servers. Here I want to mock at least the $this->service->doSomething($json) to be a no-op. Ideally, I would like to spy into the resulting $json variable to test that exactly.
No doubt, in my test class it would be something like
class TestResponseHandler extends TestCase {
public function setUp() { /* Set up the http deamon as system service */}
public testGetJson() {
// Creat Guzzle client
$client = new Client([
'base_uri' => 'http://localhost:8080/apps/cookbook',
]);
// Run the API call
$headers = ...;
$body = ...;
$response = $client->put('recipe/15', 'PUT', $headers, $body);
// Check the response body
// ....
}
}
Now, I have two code interpreters running: Once, there is the one (A) that runs phpunit (and makes the HTTP request). Second, there is the one (B) associated with the HTTP server listening on localhost:8080.
As the code above with the call to getJson() is running inside a PHP interpreter (B) outside the phpunit instance I cannot mock directly as far as I understand. I would have to change the main app's code if I am not mistaken.
Of course, I could provide (more or less) useful data in the test function and let the service->doSomething() method do its job but then I am no longer testing only a subset of functions but I am doing functional or system testing. Also, this makes it harder to generate well-aimed test cases if all these side-effects need to be taken into account.

PHPUnit mock request object and extract body and header

How do I unit test for my code which makes http requests . Instead of making actual http call, I want to use mock objects and verify http request has has correct body and headers set.
Your description doesn't contain a lot of information. But for the start I can guide you using this example code.
$httpMock = $this->getMockBuilder('\Vendor\Path\HttpHandlerYouWantToMock')
->disableOriginalConstructor()
->setMethods(['setBody', 'setHeader'])
->getMock();
$httpMock->expects($this->once())
->method('setBody')
->with($this->identicalTo('{"test":"test"}'));
$httpMock->expects($this->once())
->method('setHeader')
->with($this->identicalTo('Content-Type: application/json'));
$service = new SomeService($httpMock);
$service->post('/someApi', '{"test":"test"}');
This code just in a representation how all should look like but in your case I have no idea what http handler are you using or if this one contain any other services that is dependent on.
So main idea just mock all your services that are used by your own service. And define for this mock what methods you think will be used an what data should be passed there.
And the last use the phpunit documentation https://phpunit.de/manual/current/en/test-doubles.html

Dependency injection php website

The more I read about dependency injection the more I get confused. I know what it is for, that is not the problem. Trying to do some design on paper this is what I came up with and somehow it seems to me I am overlooking something.
First I imagined building an actual server that would accept incoming requests and returns responses to the user.
class Server {
private $responseBuilder;
public function __construct($responseBuilder) {
$this->responseBuilder = $responseBuilder;
}
public function run() {
// create socket, receive request
$response = $this->responsebuilder->build($request);
// send response
}
}
class Response {
private $method;
private $message;
private $url;
// getters & setters
}
class ServerBuilder {
public build() {
// construction logic
return new Server(new ResponseBuilder());
}
}
Since Apache is used to handle server requests we could replace the server with something that just send the response.
$bldr = new ResponseBuilder();
$response = $bldr->build();
// send response some way
Note that ResponseBuilder has direct access to the request ($_SERVER['..'])
and so it has everything it needs to choose the right response.
PHP however allows us to build and send responses inline. So we could have a Controller object for each page or something else that send the response and have a builder for that.
$bldr = new ControllerBuilder();
$controller = $bldr->build();
$controller->run();
class ExampleController implements Controller {
public function run() {
header("HTTP/1.1 404 Not Found");
echo 'sorry, page not found';
}
}
This all makes sense to me. But let's look at the server example again.
It calls $responseBuilder->build() and gets a response back. But this would mean that the builder (or other builders if we split it) is also responsible for anything else that might occur like authenticating a user, writing to the database,... and I can't get my head around the fact that writing to a database would be part of the object graph construction.
It would be like: Send me your request. Oh you want the homepage? I will build you your response and while I'm at it I will also do some things that have nothing to do with building it like logging what I just did and saving some of your data in a cookie and sending a mail to the administrator that you are the first visitor on this page ever, ...
You should decouple them. You have a few assumptions that I think are a bit strange. Let's start with them.
The main purpose of an incoming http request is to give back some html
I have built PHP backends that only return JSON, instead of HTML. I had a really strong border between back and front end. I only used the backend to give me data from the database, or add/edit data in the databse. The front end was just a PHP script that would build the pages any way i wanted.
Since it is the web there is in theory no use for setters since
everything can be injected in the constructor
You could use the constructor, but you don't have too. You can use setters. Dependency injection is actually just turning the flow around.
You are on the right track though. You want some class that is responsible for building your pages. So, make it only responsible for your building your pages, and take out the other responsibilities. Things like logging, authentication etc should be outside of that.
For instance if you want logging, you could have your builder create your page, and your logger could then listen to all the things your builder is doing (with the observer pattern for instance). So if your builder says: "i created the home page", you can log it with your logger, who is actually listening to your builder.
Authentication for instance should happen even before your builder starts. You don't want your builder to go to work if you can already figure out that a user is not supposed to be on a page. You could use a database for that, and whitelist any usertype/pagerequest combination.
Then for data handling, i would create a backend, that only handles requests that are supposed to give back data, or save it. The front end could then communicate to get it's content by pulling it.
I hope this clears up a few things, but I'll be happy to answer more indept questions.

AWS S3 SDK for PHP 2 - Get HTTP Request/Response Strings

I have a generic HTTP file access API which I use for the system I'm working on. To make it as flexible as possible, it returns request and response data in the form of HTTP strings.
I'm currently implementing a version which interacts with the S3, via the AWS SDK for PHP 2.
Is there an easy way to quickly get the Request and Response HTTP requests which the S3Client makes when performing operations? If not, is there a more piecemeal way which I can use to not have to fake it?
Basically, I'd like the full-text of both the Request and Response on demand, or at least access to relevant data (headers, response codes, URLs, etc) so I can properly populate the return data for my framework.
Thanks.
You can get either the request or response object from a command object. Assuming $s3 holds an instance of Aws\S3\S3Client, you could do something like this:
$command = $s3->getCommand('ListObjects', array('Bucket' => '<bucket-name>'));
$request = $command->getRequest();
$response = $command->getResponse();
Those objects have methods for viewing the body, headers, status codes, etc. and you can cast them to string to see the string form.
If you want to quickly see the request and response as you are executing commands, you can attach the wire logger, and see what comes out on STDOUT (or STDERR)
$s3->addSubscriber(\Guzzle\Plugin\Log\LogPlugin::getDebugPlugin());
$s3->listObjects(array('Bucket' => '<bucket-name>'));
You will need to look into the Guzzle\Http\Client class, which is an ancestor class to S3Client, to have a look at the methods that it makes available. You can always override some of these methods in your own child of S3Client to make accessing this information easier for you.
Ultimately the data you are looking for resides in an object of class Guzzle\Http\Message\Response, which I believe is returned from Guzzle\Http\Client::send().
So perhaps in your own implementation of S3Client you can override the send() method to send the HTTP requests, then process the response data as needed.

ZF + PHPUnit: How to assert existence of html elements within ajax response?

Should I extend the ControllerTestCase and create a custom method to handle this? What is the best way?
AJAX response should be no different than any other response. So no subclassing should be necessary.
But if you mean "how to test that the response AJAX request generated from the file I'm testing is correct?" there is no way to do that (except Selenium tests maybe). And it's not PHP's job to test this - you should use JavaScript tests to test it.
When you're sure the AJAX is calling correct URL with correct params, you can create the AJAX request artificaly and test the response as normal request.

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