RESTful API Development for ASP.NET Core

Join Stormpath .NET Developer Evangelist, Nate Barbettini, to learn best practices for designing your REST API in ASP.NET Core. Nate will explain how to build HATEOS-compliant JSON APIs while supporting security best practices and even improving performance and scale.

Topics Covered:
What is REST and HATEOS?
How to think about RESTful APIs
How to model hypermedia in C#
Building JSON APIs in ASP.NET Core

Transcript

1. BEAUTIFUL REST APIs in ASP.NET Core Nate Barbettini @nbarbettini recaffeinate.co .ws
2. Welcome! • Agenda • Stormpath 101 (5 mins) • REST APIs in ASP.NET Core (60 mins) • Q&A (15 mins) • Nate Barbettini • Developer Evangelist @ Stormpath
3. Speed to Market & Cost Reduction • Complete Identity solution out-of-the-box • Security best practices and updates by default • Clean & elegant API/SDKs • Little to code, no maintenance
4. Stormpath User Management User Data User Workflows Google ID Your Applications Application SDK Application SDK Application SDK ID Integrations Facebook Active Directory SAML
5. Overview • What is REST? • Why is API design important? • HATEOAS (Hypertext As The Engine Of Application State) • REST APIs in ASP.NET Core
6. REST vs. RPC • REST: resources and collections of resources • RPC: remote function calls
7. /getAccount?id=17 Bad REST API design /getAllAccounts /updateAccount?id=17 /createAccount /findPostsByAccountId?account=17 /accountSearch?lname=Skywalker /getAccount?id=17&includePosts=1 /getAccount?id=17&format=json /countAccounts /partialUpdateAccount?id=17 /getPostCount?id=17 /deleteUser
8. HATEOAS, yo! "A REST API should be entered with no prior knowledge beyond the initial URI (bookmark) and set of standardized media types that are appropriate for the intended audience (i.e., expected to be understood by any client that might use the API). From that point on, all application state transitions must be driven by client selection of server-provided choices that are present in the received representations or implied by the user’s manipulation of those representations." ~ Dr. Fielding Tl;dr The API responses themselves should document what you are allowed to do and where you can go. If you can get to the root (/), you should be able to “travel” anywhere else in the API.
9. Good REST design should... • Be discoverable and self-documenting • Represent resources and collections • Represent actions using HTTP verbs • KISS!
10. BEST PRACTICE #0 Plan API design from the beginning
11. Revisiting the API example /users GET: List all users POST: Create a user /users/17 GET: Retrieve a single user POST or PUT: Update user details DELETE: Delete this user /users/17/posts GET: Get the user’s posts POST: Create a post /users?lname=Skywalker Search /users/17?include=posts Include linked data
12. BEST PRACTICE #1 Follow a design spec
13. A specification for REST+JSON APIs The ION spec: https://github.com/ionwg/ion-doc
14. Getting a single user GET /users/17 { "meta": { "href": "https://example.io/users/17" }, "firstName": "Luke", "lastName": "Skywalker" }
15. Getting a list of users GET /users { "meta": { "href": "https://example.io/users", "rel": ["collection"] }, "items": [{ "meta": { "href": "https://example.io/users/17" }, "firstName": "Luke", "lastName": "Skywalker" }, { "meta": { "href": "https://example.io/users/18" }, "firstName": "Han", "lastName": "Solo" }] }
16. The starting point (API root) GET / { "meta": { "href": "https://example.io/" }, "users": { "meta": { "href": "https://example.io/users", "rel": ["collection"], } } }
17. • Install the .NET Core SDK - http://dot.net/core • If you’re using Visual Studio: ◦ Install the latest updates (Update 3) ◦ Install the .NET Core tooling - https://go.microsoft.com/fwlink/?LinkID=827546 ◦ Create a new project from the ASP.NET Core (.NET Core) template ◦ Pick the API subtemplate • Or, with Visual Studio Code: ◦ Use dotnet new -t web to create a new web project ◦ Run dotnet restore to restore NuGet packages • Ready to run! Getting started with ASP.NET Core
18. LIVE CODING
19. Best practices recap 0. Plan API design from the beginning 1. Follow a design spec 2. Use async for database access 3. Write integration tests
20. Next steps • Full example https://github.com/nbarbettini/beautiful-rest-api-aspnetcore • ION draft spec https://github.com/ionwg/ion-doc
21. Thank you! Nate Barbettini @nbarbettini recaffeinate.co .ws