I am using web api in my project to expose data which in turn is intended to be used by a mobile application and a web application.
I want to know what is the best practice to expose data.
For instance, I have a customer registration form in which I am capturing Customer details including city and country.
One way to expose the data is to have separate Controllers for cities and countries and make separate calls to both on the customer registration form in order to load the data for cities and countries.
The issue with this approach would be that if I have to load hundred fields, I will have to make hundred different call to the api to load the data and hence the application will be slow.
Second approach would be design the api layer in such a way that one controller expose all the lookup data (cities, countries) required for a form/screen (customer registration). In this case I will have to make a single call to the api to get all the required data.
It feels like, using the second approach I am violating separation of concern.
Which way to go?
Can't you just split UI and API layers?
I do not think you should create API to fetch countries or whatever else side-references if they are not core parts of your domain.
I guess you should just expose api/v1/users resource endpoint for user registration, which expects a valid user data for registration.
Plus you should expose /users UI, which will generate full UI, including all the lists you need and present it to the user. This UI controller will call your domain model internally, not via API to get all the details, needed to generate UI. And then UI on the client side will call your API controller with user selected data to register user.
Will that suite your development model?
Related
We're designing a new service orchestrator which will provide a multi-staged flow for the user and will be communicating with several foreign services internally.
I'm preparing API for it and I have a few questions:
The main flow will constitute of several web pages and each one of them will contain unique information extracted from several sources. Should we set several different API endpoints for each page or it's better to create a single endpoint which would internally decide what logic to execute based on stage/page number?
Is it ok to use POST requests for those endpoints where we could use GET, but the data there is ever-changing? I'm concerned about caching when I don't want to. Though I can always explicitly disable caching.
I am using SignalR for displaying onscreen notifications in my web application(built using Asp.net MVC).
My question is How to show notifications to specific set of users eg. Display onscreen notifications to all the users with reader role?. The roles and user associated with roles are defined the database.
I have read it in the documentation where it is mentioned about groups. But i am not sure how to use it.
As you said, one of the ways to go is by using SignalR Groups.
Basically, when you start the connection to the SignalR hub, you can also include that user in a group, based on the type of account (try not to include the user in a group based on a client function call, do it on the server).
So each time the user connects, you can override the OnConnected method and add a user on the appropriate group (in the Groups object are stored ConnectionId strings.
Note - if you are going to scale the application, you will also need to add a backplane for the following reason: the groups and the connection ids are store in the memory of the server. If your application is load balanced, then you have multiple independent instances of the same application, each one with different connections.
The way to go here is to use a SignalR Backplane.
Hope this helps!
Best of luck!
I am in the process of developing a web based solution do replace an application we provide. The web application is a record storing application and each client would have different forms they would input data into and store. My question is: Is it possible to create a backbone Web Project, which would have minimal updates this would be like a container and be the same for all of our clients, and have the document forms which would be different among clients and need to be updated more often.
Any constructive comments for or against this with reason why would also be appreciated.
It sounds like what you’re describing is a multi-tenant system if you'd like to do some research on that term. Your web interface remains the same for all, but the records/documents are different for each client. It sounds like you might need login/access functionality that ties the records to a client ID (possibly stored in a database). According to how you intend to store the records (file system vs. database), you can control access either based on the client ID (foreign key to the doc tables) or you might want to create roles. This is a very high overview for what can become complex according to the specs.
I'm not really sure how to best word this. We have an ASP.NET web application with the backend services accessible over a WCF service layer. We need to add some reporting/dashboard type bits to the web application.
To make it scalable the data needed for the reporting needs to be calculated on the backend. I'm just wondering if there is a recommended way to pass this data around. It doesn't make much sense to have different service methods to get the different bits of data, it feels like it should be summarised already.
I had a look at WCF Data Services, but that seems more for retrieving full object trees. Maybe some sort of XML document so extra items can be added to the summary without needing service layer changes?
The data would be things like number of orders today, number of orders specific to the person running it, open orders outstanding etc.
Does anyone have any pointers?
Thanks for your time
You can look at something like ASP.NET Web API and use an XML Formatter for your data. You can use ViewModels to flatten your data and send over the wire to your web app to bind to grids or whatever you need to.
Basically you would get request (filters, keywords, etc) from your web app, send the parameters to your reporting back-end, retrieve the reporting data, map the values to your ViewModels and serialize them using Web API. Using Web API you can use all kinds of formatters for your data to XML, CSV and JSON to vCard, iCal, PDF, etc...
You can read more about it here: http://www.asp.net/web-api
I am working on a railway web application and I have following layers:
ASP.NET MVC 2 (Presentation Layer)
Services Layer
Repository Layer
Database & External Web Services as data sources (Using Entity Framework for Database)
I pass Domain Entity Objects from Repository to Service layer and thinking of passing View Models from Service to Presentation layer.
Website would require a login and after successful login I have to present a search screen with basic search (as default option) and option for advance search. Once user fills the search criteria I have to gather data from DB & Web Services and present the results to user. User would select a particular Rail option and would move on to other additional options page BUT they should be allowed to change their previously selected Rail option by going back to Rail search results. I have to always hold and present user’s initial search criteria (basic and advance search options selected by user on the search wizard) on every screen and need these criteria in Service and Repository layers.
What is the best way to hold these search criteria and pass them from page to page within presentation layer and across layers? Should I create a View Model class for Search Options? Or a Domain Entity Object (I don’t think so)? Or a DTO? and best way to pass it across layers and from page to page with in presentation layer.