Routing

Goal

This snapshot advances Baltic Post by teaching you to organize page routes with the Ktor routing DSL.

Every numbered folder is a complete app. Run this stage independently, then compare it with the previous folder.

Prerequisites

Use JDK 17+, Gradle, and Docker for Postgres stages.

Port 8090 must be free. Copy .env.example before starting database stages.

• JDK 17+ and Gradle
• A code editor and terminal
• Docker from part 4 onward

Concepts

The routing block maps verbs and paths to handlers.

Keep handlers thin: routes accept input, Exposed tables enforce rules, and FreeMarker escapes output by default.

Walkthrough

Add home, about, and health routes.

Read the example, then open the matching snapshot. The repository includes the surrounding setup and error handling.

get("/about") { call.respondText("About Baltic Post") }

Run and verify

Enter 02-Routing, run Gradle, copy .env.example, and start Ktor on port 8090.

Open http://127.0.0.1:8090. Watch the terminal for validation and database errors.

git clone https://github.com/michaeldunga1/fcc-ktor-blog.git
cd fcc-ktor-blog/02-Routing
cp .env.example .env
./gradlew run

Troubleshooting

A missing route leaves the path undefined.

For database failures, confirm Docker and the baltic_NN name when applicable. Never commit .env or local.properties secrets.

• Read the first error first
• Restart after environment changes
• Never commit secrets

Try this

Add a /contact plain-text route.

Test a happy path and one invalid or unauthorized request.

• Make one small change
• Test it in the browser
• Compare with the next snapshot only after it works