Canonical MVC Model for Java Web? - model-view-controller

I am attending a training course where they presented the following model, with a claim that all modern Java web frameworks more or less implement it. I think it is too sweeping of a statement but I want to get it verified. Here is the model:

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Implementing Web API Identity

I am trying to find an up to date, clear and simple explanation of an implementation of ASP.NET Identity. The problem is that most tutorials get bogged down with Entity Framework discussions or branching off into territory which, while useful, is best for those who probably know "Identity" already.
TL:DR; I would like a link to a good description of how to implement ASP.NET Identity.

how to implement Complex Web API queries in ASP Core

I'm new to web API design, so I've tried to learn best practices of web API design using these articles:
1.Microsoft REST API Guidelines
2.Web API Design-Crafting Interfaces that Developers Love from "Apigee"
Apigee is recommending web API developers to use these recommendations to have better APIs.
I quote here two of the recommendations:
I need C# code for implementing these recommendations in my Web APIs (in ASP Core) which is a back-end for native mobile apps and AngularJs web site.
Sweep complexity behind the ‘?’
Most APIs have intricacies beyond the base level of a resource. Complexities can include many states that can be updated, changed, queried, as well as the attributes associated with
a resource.
Make it simple for developers to use the base URL by putting optional states and attributes behind the HTTP question mark. To get all red dogs running in the park:
GET /dogs?color=red&state=running&location=park
Partial response allows you to give developers just the information they need.
Take for example a request for a tweet on the Twitter API. You'll get much more than a typical twitter app often needs - including the name of person, the text of the tweet, a timestamp, how often the message was re-tweeted, and a lot of metadata.
Let's look at how several leading APIs handle giving developers just what they need in
responses, including Google who pioneered the idea of partial response.
LinkedIn
/people:(id,first-name,last-name,industry)
This request on a person returns the ID, first name, last name, and the industry.
LinkedIn does partial selection using this terse :(...) syntax which isn't self-evident.
Plus it's difficult for a developer to reverse engineer the meaning using a search engine.
Facebook
/joe.smith/friends?fields=id,name,picture
Google
?fields=title,media:group(media:thumbnail)
Google and Facebook have a similar approach, which works well.
They each have an optional parameter called fields after which you put the names of fieldsyou want to be returned.
As you see in this example, you can also put sub-objects in responses to pull in other information from additional resources.
Add optional fields in a comma-delimited list
The Google approach works extremely well.
Here's how to get just the information we need from our dogs API using this approach:
/dogs?fields=name,color,location
Now I need C# code that handles these kind of queries or even more complex like this:
api/books/?publisher=Jat&Writer=tom&location=LA?fields=title,ISBN?$orderBy=location desc,writerlimit=25&offset=50
So web API users will be able to send any kind of requests they want with different complexities, fields, ordering,... based on their needs.

What are the good practices and useful design pattern to provide an API which supports internationalization?

Given an existing API working well with the usual mono-locale approach, what are the steps one should follow to turn it into an internationalized version, which enable user to send/receive keys/values in localized versions?
End user interface internationalization is a well covered topic.internationalized. But how can it be pushed further on request and response? If someone hits an API and wants the response in German how can I do so ?
It is kind of tricky answering without any kind of context, or sample API, or a even a high-level description of what your API does.
But in general it is best to separate your APIs into several layers.
The core functionality and data at the application level should be locale independent, something like this http://mihai-nita.net/2005/10/25/data-internationalization/
Then you would have the presentation layers, with things like date/time/number formatters, collation, localization, etc.

Why is MVC used on the server? Isn't it a client-side pattern?

I'm trying to learn web development.
I understand (mostly) the concept of MVC, but I'm confused about why an MVC model is used on the server side...like Spring MVC. Isn't the server side the Model and Services, and then the client side Services, View, and Controller (AngularJS even makes that pattern explicit on the client side)?
I'm really struggling with how the MVC model fits into or facilitates server-side development.
MVC is a pattern used by much more than just web applications. Any app with a UI could use an MVC pattern.
The idea is that you have a View (html, or a window in your OS, or even a report or something), and you have a model that represents the dynamic parts of that view. Then you have a controller that is dedicated to processing input and doing the "business logic" to generate the model and apply it to the view.
So.. for example on the Server you might have this MVC pattern:
A controller receives the HTTP request and processes it.
It builds a model
The model is applied to a view to generate HTML and send it back as a response.
On the client it will be similar (but a bit different in Angular's case):
A controller is used to determine and manipulate the model.
The model is then bound to your view via directives. (Angular is really more of an MVVM pattern, but it's similar enough)
The view is similarly bound to your model via directives. (this is where the MVVM part comes in).
The idea here is that both the model and the view are kept up to date by directives.
The controller just contains "business logic" for manipulating the model.
Clear as mud?
No worries. Just know this: It's just a common pattern. It's not "server specific" or "client specific". It can be used anywhere by anything requiring data to be scrubbed into templated output.
EDIT: More thoughts.
In the case of a Web API that serves up JSON (or even XML) on the server, you're still using MVC in most cases. This is because what you're doing is:
Process the request in a controller.
Build up the model in the controller.
Render the model to a "view", which in this case is a view that serializes it out as JSON.
In the good ol' days of yore, the client side was only a display. The server was responsible for communicating with the model, applying business logic, generating a view, and sending the static, rendered content back to the client (browser).
As the web matured, some of those responsibilities migrated from the server to the client. Now, the server-side is often a thin layer like RESTful API that stores the "official" business logic (rather than convenience logic on the client) and stores the model. But for performance and user experience, the client now stores a copy of the model in its own model layer, communicating with the server and/or local storage as necessary, and having its own controllers and view logic to provide an awesome user experience.
So does MVC still apply on the server? Yes! It's just different. The server often generates the initial view from which the client-side application runs (taking localization or internationalization into account, for instance) and still houses the official model. But more importantly, the "view" in MVC just changed. Instead of the server-side view being HTML, it's now JSON or XML that the client application consumes instead of just renders.
So for functionality's sake, we still use MVC on the server. But for an awesome user experience, we use MVC on the client-side now too.

Session State with MVP and Application Controller patterns

I've created an MVP (passive view) framework for development and decided to go for an Application Controller pattern to manage the navigation between views. This is targeted at WinForms, ASP.NET and WPF interfaces.
Although I'm not 100% convinced that these view technologies really swappable, that's my aim at the moment so my MVP framework is quite lightweight.
What I'm struggling to fit in is the concept of a "Business Conversation" that needs state information to be either (a) maintained for the lifetime of the View or, more likely, (b) maintained across several views for the lifetime of a use case (business conversation). I want state management to be part of the framework as I don't want developers to worry about it. All they need to do is to "start" a conversation, "Register" objects and the framework does the rest until the "end" a conversation.
Has anybody got any thoughts (patterns) to how to fit this into MVP? I was thinking it may be part of the Application Controller responsibility (delegating to a Conversation Manager object) as it knows about current state in order to send the user to the next view.... but then I thought it may be up to the Presenter to start and end the conversation so then it comes down the presenters to manage conversations and the objects registered for the that conversation. Unfortunately that means presenters can't be used in different conversations... so that idea doesn't seem right.
As you can see, I don't think there is an easy answer (and I've looked for a while). So anybody else got any thoughts?
The classes needed to support a Business Conversation should reside in a presenter if it only involves the User Interface. Otherwise it should be in the Model and controller from the View to the Presenter to the Model. With information about Business Conversations flowing the other way. I suspect is something that can reside just in the Presenter.
Since all Views have access to the Presenter you then have the ability to structure the objects supporting the conversation so that they can be maintained across several views.
Remember Views are a window into what data resides in your software. They did little other display data and pass user interactions back into the presenter which does the logic.

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