data-api

Template .NET Core Web API

This is a .NET Core 2.1 LTS project. 2.1 is currently the highest version supported by Google App Engine. (3 is the latest)

Setup

Environment Variables

JWT_SECRET=AnySecretStringGoesHere
- Used to sign and verify JWT Tokens - Make up any string for a secret. This is so we can trust the data in the tokens we read.
LOCAL_DB_CONNECTION=Data Source=localhost;Initial Catalog=datapidb;User ID=serveruser;Password=pass
- DB Connection String - Some insecure example user credentials

MySQL Setup

There is an included sample database schema along with some records.

Run the /db/datapidb.sql file on a local mysql instance.
Credentials for the sample database from the file are
- user: serveruser
- password: pass

Building the Project

CLI

Navigate to the application directory
- cd ./data-api
Create the build
- dotnet publish -c Release
Navigate to where the executable was built:
- cd /bin/Release/netcoreapp2.1/publish/
Run it. The port will be determined by the "applicationUrl" value in /data-api/Properties/launchSettings.json
- dotnet data-api.dll

How it Works

Quick information to get you started with the structure of MVC .NET Core:

Controllers

Controllers are methods bound to route handlers along with their parameters. Parameters in these methods can have annotations to indicate that the value comes from the request body, header, or query parameters.

Controller Example:

Models

Models are mainly used to interact with the database and issue queries.

Middleware

Middleware is applied to requests before they reach the controller methods. Common usages of middleware are to check for authentication and modify headers. Another good usage is to log request traffic & usage. Multiple middlewares that call a next method are frequently used to run several processes before handling the request. If a middleware class' Invoke method is not called, the request is short-circuited and the controller never receives the full request. It is up to the middleware that terminates the request to set an appropriate status code and return a meaningful error message.

Middleware Example

The Invoke(HttpContext) method is given to any class to be used as middleware. When the middleware is called this method takes the HttpContext which includes the request and response (to be sent) data. Any middleware's Invoke method can be used to affect the response after the controller method has been called in the part of the method below the call to next(context).

 public async Task Invoke(HttpContext context)
        {
            Guid sessionID = Guid.Parse(context.Request.Headers[HeaderFields.SESSION_ID_HEADER_NAME]);

            logger.LogInformation("Incrementing request count on session id: " + sessionID.ToString());

            // No need to await the increment log query.
            UserSessionsModel.IncrementSessionRequestCount(sessionID);
            UserSessionsModel.UpdateSessionLastRequestTime(sessionID);

            await next(context);
            
            // Any code here is meant to affect the response
        }

Authentication

Documentation

Code (Javadoc)

REST API

Testing

An awesome feature of testing in ASP.NET Core is the ability to test route handlers and their corresponding controller methods in a single call. This may not seem like a significant feature but after working with testing route and controllers in Node.js this is a huge convienience.

routonmh/data-api