Using Filter

Filters are things you can do before or after the actual executable actions.

The order of filter goes like this,

IAuthenticationFilter > IAuthorizationFilter > iActionFilter > IResultFilter

and if during Action, exception occur then IExceptionFilter

You can set filter at web.config or by having bracket at the top of classes.

IExceptionFilter

One of the main attribute in IExceptionFilter is HandleError Attribute.  Here we want to tell the system what we want do when exception occurs.  (we want to tell what to do when an error happens.)

Custom Errors

You can do display error  page with detail message, with out much of message,  or redirect to custom page when the error occurs.

Usually you will choose RemoteOnly option, which is to display detail error message at local environment and hide detail error message at online environment.

I will cover about handling error more later.  I just let you know IExceptionFilter is here.

Handling Cache

You can specify how to use cache by having [OoutputCache(duration=240)] at the head of classes.  Or at Web.Config

You have create profile at Web.Config then you can use them like

When using partial views, you can specify cache rules to partial view only or both partial and main view.

Controller

View

 

and more to be continued.

ActionResult

ActionResult is an object used in ASP.Net MVC.  ActionResult returns or passes things like ViewResult to views and many more.

If you simply want to return view then

If you want to redirect user to other url

If you want to redirect user to another action

If you want to add some parameters to the action

If you just need to return https status code result, you can also use (include System.Web.Mvc).  Check https://msdn.microsoft.com/en-us/library/system.web.mvc.httpstatuscoderesult(v=vs.118).aspx for more detail.

There are more in HttpStatusCode, and you can return more precise and appropriate status code to the user;

  • Member – Status Code
  • OK – 200
  • Created – 201
  • MovedPermanently – 301
  • Found – 302
  • SeeOther – 303
  • BadRequest – 400
  • Unauthorized – 401
  • Forbidden – 403
  • NotFound – 404
  • MethodNotAllowed – 405
  • InternalServerError – 500

I haven’t use this myself, but you can return nothing too

You can also simply return contents like text

I ll introduce more about later.

 

Mastering Azure DocumentDB Part 1

If you are looking for a full coverage of DocumentDB and developing web services based on DocumentDB in ASP.Net C# MVC, you have come to the right place. well, almost, working on it.


Index

  • What is DocumentDB
  • Pricing
  • Using DocumentDB
    • Getting Started with .Net SDK
    • CRUD of Database
    • CRUD of Collection

 

What is DocumentDB

DocumentDB is the NoSQL database service from Azure.

DocumentDB is native in JSON, means you can post JSON format data and be able to query them like SQL.  This is convenient in modern web services, because the service is not tied to previously defined data schema, which has been a headache for all web service developers, because the service needs ever improvement and that often means data schema changes.

DocumentDB  is configurable to scale linearly.  This is important concept so I ll cover this fully later.

DocumentDB is manageable via REST API, or can be managed from SDK for JavaScript, Java, Node.js, Python and .Net. But I ll be covering SDK for .Net first.


Pricing

Pricing is applicable at collection level and charged per hour. (What is collection? I ll get to that later) There are 3 tiers, all same storage capacity, difference is how much request units they can handle per second.  Request unit is basically a transaction of the database.

  • S1 250 request unit / sec reserved and  $0.039 per hour (that is up to $29 per month)
  • S2 1,000 request unit / sec reserved and $0.076 per hour (that is up to $57 per month)
  • S3 2,500 request unit / sec reserved  and $0.154 per hour (that is up to $114 per month)

This sounds pretty reasonable for me.  Please be sure to refer to limitation of DocumentDB when you choose your service grade.


 

Using DocumentDB

In DocumentDB, there are 3 layers of structures

  • Database
  • Collection
  • Document

What are all these means?  Don’t worry about details for now-now, but these are containers and how each object exist within.  And I ll talk more about what each of these containers are and mean.


 

Getting Start with .Net SDK

I will be using SDK first, so ., once you create ASP.Net MVC project, the first step is to download SDK. You can nuget it or get it from github (https://github.com/Azure/azure-documentdb-dotnet).  You can also do same by calling REST API, but I will cover that when I use DocumentDB with other programming language later.


The top level container of DocumentDB is database.  So, first, let’s go over CRUD of database.

CRUD of Database

When you work with DocumentDB you need end-point URI and authorized key code.  I will store these values into my Web.config file like below.

If you already know which database to work with, you can also store database name to make your life simpler and easier.

Get A List of Databases

Controller

View

And now you should list of database you have in the account like below.

スクリーンショット_013116_064600_PM

I currently have one in my account already.  Let’s add another one and see.

Create Database

Database is simply a container of JSON document, with capability to have user access logic built in.  If you want to have different user access level at server side, then you can have separate that database and create collections within.  Creating database is free but you can only make up to 100 databases per account.  (see more at limitation of DocumentDB)

Controllers

View

This is what it looks like at input interface.

スクリーンショット_020116_124451_AM

After I run and create database, I am redirected to the list of existing databases and see SandBagDatabase which is database I just added. Super.

スクリーンショット_020116_125044_AM


Now that you can view and add databases, let’s take a look at collections.  Which is one below level container of DocumentDB Databases. Collection is where Azure charges and can choose performance levels and more.

CRUD of Collection

Get A List of Collections

List of collection can be obtained from building CollectionQuery (CreateDocumentCollectionQuery) and running it. That is;

I am totally trusting that databaseName which is passed variable to be rigid, but I may want to think about that later.

Controller

View

Right now I don’t have any collection so I should see nothing like below;

スクリーンショット_020116_020826_AM

Creating Collection

Now let’s create collection and see.

Controller

View

The input interface looks like below;

スクリーンショット_020116_111757_AM

After I type in collection name and click on Create Collection button, now I see new collection being added properly. Super!

スクリーンショット_020116_112448_AM

 

Please continue on to part 2 for reading more about working with Documents.

FormExtentions

Mastering form extension is very important because when you are writing modern web services, almost always you will be using form extension to take input from users.  You will be using form extensions frequently for ever, so better master this first.

You can refer to full class documentation here.
https://msdn.microsoft.com/en-us/library/system.web.mvc.html.formextensions.beginform(v=vs.118).aspx

The basic form is like this

which generate html code like below

We usually have two types of forms, one that link to the model and one that is not link to the model.

We will look more into how you can build model that work well with forms later.