Planned lessonJNR-012-L04

Property-source precedence

On This Lesson 4 topics

This lesson is planned. The outline below lists the topics it will cover. The full lesson has not been published yet.

In this lesson

know which value wins.

Many sources can set one property; Boot defines an order, highest priority first (summary).
Command-line arguments beat environment variables, which beat profile files, which beat the base application.yml.
Defaults in code are lowest.
Environment variable SHOP_TAXRATE or SHOP_TAX_RATE maps to shop.tax-rate by relaxed binding.
Secrets belong in the environment or a secret store, never in committed YAML. Verify the full order in the docs for your version.

Draft outline details

a ladder: command line → env vars → application-{profile}.yml → application.yml → defaults.

Which wins: env var or application.yml?

Show answer

The environment variable.

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