Spring JSON Merge Patch demo

Demonstration of updating and keeping fields using the JSON Merge Patch.

Requirements

• Java 21

How to run

./mvnw clean spring-boot:run

Demo

Step 1: See the initial data.

curl -XGET "http://localhost:8080/users/1"

{"id":1,"username":"alice","familyName":"Liddell","givenName":"Alice","age":7}

Step 2: Update age and delete familyName by JSON Patch Merge request.

curl -XPATCH -H"Content-type:application/merge-patch+json" http://localhost:8080/users/1 -d '{"age":17, "familyName":null}'

{"id":1,"username":"alice","familyName":null,"givenName":"Alice","age":17}

Step 3: See the updated data.

curl -XGET "http://localhost:8080/users/1"

{"id":1,"username":"alice","familyName":null,"givenName":"Alice","age":17}