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+# Endpunkte
+
+GET    /api/person                      -> Get all persons
+GET    /api/person/username/{username}  -> Get person
+POST   /api/person                      -> Create
+PUT    /api/person/username/{username}  -> Update
+DELETE /api/person/username/{username}  -> Delete
+
+# Personen-Modell
+
+String username
+String realName
+DateOnly birthday
+
+# Beispiele
+## Beispiel 1
+Request:
+POST /api/person
+{
+  "username": "marco",
+  "realName": "Marco",
+  "birthday": "2000-01-26"
+}
+
+Response: 201
+
+## Beispiel 2
+Request:
+POST /api/person
+{
+  "username": "m",
+  "realName": "Marco",
+  "birthday": "2000-01-26"
+}
+
+Response: 400
+
+## Beispel 3
+
+1. Request:
+POST /api/person
+{
+  "username": "marco",
+  "realName": "Marco",
+  "birthday": "2000-01-26"
+}
+Response: 201
+
+2. Request:
+POST /api/person
+{
+  "username": "marco",
+  "realName": "Marco",
+  "birthday": "2000-01-26"
+}
+Response: 409
+
+## Beispiel 4
+
+
+Request:
+POST /api/person
+{
+  "username": "marco",
+  "realName": "Marco",
+  "birthday": "2020-01-26"
+}
+Response: 400 Person muss 16 Jahre alt sein