I have a symfony 2 application where I set up a kernel.request listener to perform dynamic url checking by loading a corresponding entity from db.
The entity that is loaded then gets attached to a service, so that throughout the application who ever needs that data can ask the service for it.
Reviewing the code I was tempted to simply attach the entity to the Request object. It kind of makes sense, since this entity is used everywhere in the application, and it's determined by a url component.
Is that a proper way to use the Request, or is it better to leave it incapsulated into a service?
Thanks in advance
sergio
Related
This is a question to improve my understanding about OData and the process of OData services. I'm not sure about the process when an OData request is sent to the server from my Fiori app. The app is added to our Fiori Launchpad. When the user wants to create a new target group in the UI, a create request is sent. What happens then in detail? What I thought so far:
OData service checks the data
If the data is valid, a new entry in the database is created (HTTP POST)
If the data is not valid, the OData service sends an error
I'm not sure about what information is delivered by the OData service and what information is delivered directly from the database? Does the OData service work like a adjustor which transfers the messages sent from the database to the application?
I hope you can understand what I'm trying to figure out. Thank you for your time.
it depends how your backend-methods are implemented. Every Entityset usually has one of these Methods:
Get Entity
Get EntitySet
Create
Update
Delete
There are some more I guess, but these are mostly used by developers. You can redefine every single method and implement your own Business Logic in there.
So, let's assume you want to send data from the Frontend to your service and insert the data into a table inside your database. You have to redefine the create method of your entity and implement own logic. This could contain an insert into a database-table. You have to consider, that your oData Service will throw an Error if the types which are sent from the frontend do not match the Entity-Types (i.e. a String into an edm.Time type).
Here you can find all EDM.Types oData could consume and the correct mapping of the types:
https://help.sap.com/saphelp_gateway20sp12/helpdata/en/76/4a837928fa4751ab6e0a50a2a4a56b/frameset.htm
Hope this helps :)
I need to be able to make some request data from one controller available in another controller. I can make a service to set the data in one controller, but when the other controller fires and I get the service, a new instance of the service is created. Is there any way I can make this data static and share it between two controllers?
The same basic things you would do whenever you need information to be available in PHP from a new request:
Store it in the session. Symfony2 has a great session component for this. Ideal for fleeting data that needs to be saved only while the user is navigating
Store it in the database. Symfony2 supports Doctrine which makes this very easy. Ideal for permanent storage
Optionally:
Store it on the filesystem. Not recommended unless it's actually a file, but possible as well.
In the end, rather than using the session to store data, I created two separate routes to the same controller action. I added an optional argument in the controller action, with a default value only specified in one of the routes. I can then test for that argument's value when the controller runs. In the Twig template that calls this controller action, the path can be generated using either one of these routes, depending on a variable already available.
Bit of a work around, but problem solved!
I'm quite new to Symfony 2 and I'm moving to advanced topics like services. When should an object be a service?
For example, say that you have a facade object for making a call to a REST service. This class needs a username and password. Would it be correct modeling that class as a global service? Even if it's used only in a portion of the whole project?
# app/config/config.yml
parameters:
my_proxy.username: username
my_proxy.password: password
services:
my_proxy:
class: Acme\TestBundle\MyProxy
arguments: [%my_proxy.username%, %my_proxy.password%]
Definition taken from the Symfony2 glossary:
A Service is a generic term for any PHP object that performs a specific task. A service is usually used "globally", such as a database connection object or an object that delivers email messages. In Symfony2, services are often configured and retrieved from the service container. An application that has many decoupled services is said to follow a service-oriented architecture.
I think your example is a perfect candidate for a service.
You don't want to copy construction code to all places you need your API client. It's better to delegate this task to the dependency injection container.
This way it's easier to maintain (as construction happens in one place and it's configurable).
It's also more flexible as you can easily change the API client class without affecting code which uses it (as long as it implements the same interface).
I don't think there's a golden rule. But basically all classes implementing a task are good candidates for a service. Entities on the other hand are not as they're most often just data holders.
I always recommend Fabien's series of articles on the subject: http://fabien.potencier.org/article/11/what-is-dependency-injection
Yes, because this will spare you the configuration part. You're not going to fetch the username and password and give it to the constructor each time you need this class.
Ok, so the problem is:
I've got some 'order' entity, and it has 'status' property. On changing status, i wanted some other objects to be informed of this event, so i've decided to use Observer pattern. One of the observers notifies clients via email. Now i want to render Email text's from some of the twig templates. As i get from the Book, rendering templates in controllers are done with 'templating' service.
So the question as it follows: How can i access 'templating' service in my Observer class?
Specification:
I was advised, to implement my Observer as a service, but i'm not sure 'bout that. I've tried to solve this problem, and here is my options:
Use Registry. Solution that is straight and hard as rail. I guess it misses the whole point of DI and Service Container. Huge plus of this solution, is that i can access all common services from any point of my application.
To pass needed services from the context via constructor, or via setters. This is more like in Sf2 spirit. There comes another list of problems, which are not related to this question field.
Use observers as a service. I'm not really sure 'bout this option 'cos, in the book it is written, that service is a common functionality, and i don't think that observing entity with number of discrete properties is a common task.
I'm looking for a Sf2 spirit solution, which will be spread over whole project, so all answers with an explanation are appreciated.
As with any other service in a Symfony2 project, you can access it from within other classes through the dependency injector container. Basically what you would do is register your observer class as a service, and then inject the templating service into your observer service. See the docs for injecting services.
If you're not familiar with how Symfony handles dependency injection, I'd suggest reading that entire chapter of the documentation - it's very helpful. Also, if you want to find all the services that are registered for application, you can use the console command container:debug. You can also append a service name after that to see detailed info about the service.
Edit
I read your changes to the question, but still recommend going down the DI route. That is the Symfony2 spirit :) You're worried that your observer isn't common enough to be used as a service, but there's no hard rule saying "You must use this piece of code in X locations in order for it to be 'common'".
Using the DIC comes with another huge benefit - it handles other dependencies for you. Let's say the templating service has 3 services injected into itself. When using the DIC, you don't need to worry about the templating service's dependencies - they are handled for you. All you care about is telling it "inject the templating service into this other service" and Symfony takes care of all the heavy lifting.
If you're really opposed to defining your observer as a service, you can use constructor or setter injection as long as you're within a container-aware context.
Is it possible (in a clean fashion) to create an audit interceptor in hibernate 2.1 and pass in a domain context to it?
What I would like to achieve is to set a Date Time (can be done easy peasy - found loadsa articles after a quick google), but setting an object e.g. a user who created the item, or altered an entity I have yet to find anything which covers this.
Since I will not know the object at application request/start up (which is where i have to register the nhibernate interceptor), does anyone know of a suitable workaround?
Thanks in advance, Mark H
You can store the user in the current session (HttpContext.Session) or use thread local data. It can then be accessed by the listener. If you go for the thread local approach, you will need to set if for each request, for instance with an HttpModule. Not perfect, but that's how I've seen it done in java (not exactly the same, but a similar approach).