create get single planet, update and deleted

app/routes/planets_routes.py

@@ -1,4 +1,4 @@
-from flask import Blueprint, abort, make_response, request
+from flask import Blueprint, abort, make_response, request, Response
 from app.models.planets import Planet
 from ..db import db
 
@@ -28,7 +28,57 @@ def get_all_planets():
     response_body = [planet.to_dict() for planet in planets]
 
     return response_body, 200
-
+
+@planet_bp.get("/<planet_id>")
+def get_single_planet(planet_id):
+    planet = validate_planet(planet_id)
+
+    return planet.to_dict()
+
+
+def validate_planet(planet_id):
+    try:
+        planet_id = int(planet_id)
+    except:
+        response = {
+            "message": f"Planet {planet_id} invalid"
+        }
+        abort(make_response(response, 400))
+
+    query = db.select(Planet).where(Planet.id == planet_id)
+    planet = db.session.scalar(query)
+
+    if not planet:
+        response = {
+            "message": f"Planet {planet_id} not found"
+        }
+        abort(make_response(response, 404))
+
+    return planet
+
+@planet_bp.put("/<planet_id>")
+def update_single_planet(planet_id):
+    planet = validate_planet(planet_id)
+    request_body = request.get_json()
+
+    planet.name = request_body["name"]
+    planet.description = request_body["description"]
+    planet.diameter = request_body["diameter"]
+    planet.number_of_moons = request_body["number_of_moons"]
+
+    db.session.commit()
+
+    return Response(status=204, mimetype='application/json')
+
+@planet_bp.delete("/<planet_id>")
+def delete_single_planet(planet_id):
+    planet = validate_planet(planet_id)
+
+    db.session.delete(planet)
+    db.session.commit()
+
+    return Response(status=204, mimetype='application/json')
+