Tutorials Microservices with .NET
JWT Authentication in API Gateway — Complete Guide
JWT Authentication in API Gateway — Complete Guide: free step-by-step lesson with examples, common mistakes, and interview tips — part of Microservices with .NET on Toolliyo Academy.
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Microservices with .NET · Lesson 50 of 120
API Gateway Security
Beginner ✓ → Intermediate → Advanced → Professional
Intermediate · 2 — Building services · ~6 min · Module 5: API Gateway
What is this?
API Gateway Security is a key part of ShopNest Cloud-Native — your .NET microservices learning project. In plain terms: it helps User Service work correctly in a distributed system where each app deploys and scales on its own.
Why should you care?
You care about this when mobile apps and browsers need one front door URL — not eight different service ports.
See it live — copy this example
Create a Web API project (dotnet new webapi), paste the code, then run dotnet run.
builder.Services.AddReverseProxy()
.LoadFromConfig(builder.Configuration.GetSection("ReverseProxy"));
// appsettings: /api/orders → order-cluster
Run Example »
This lesson uses terminal or setup steps. Run commands on your computer — the live editor appears on coding lessons.
What happened?
- The example shows API Gateway Security wired into User Service.
- Read each line, run it locally, then change one setting and observe what breaks or improves.
- That is how teams learn in production too — small experiments, not big bang rewrites.
Try it yourself
- Open or create the ShopNest project area for User Service.
- Apply the API Gateway Security pattern from the lesson example.
- Run dotnet build && dotnet run (or docker compose up when the lesson uses containers).
- Change a string or number in the example and run again — predict the output first.
- Break the code on purpose (remove a semicolon), read the compiler error, then fix it.
Remember
API Gateway Security connects to User Service in ShopNest Cloud-Native. Practice by editing the example yourself — do not only read. Move on when you can explain this topic in your own words without looking.
Real-world: HDFC-style fund transfer
Transfer, ledger, fraud check, and SMS run as separate services with idempotency keys. Saga compensates if fraud blocks after debit.
Outcome: Salary-day load handled without duplicate debits or shared-database locks.