Rename build_database.py to init_database.py

Author: acsany

build-a-rest-api-frontend/README.md

@@ -21,10 +21,10 @@ Then you can navigate into the folder `source_code_start/` and create a new data
 
 ```sh
 (venv) $ cd source_code_start
-(venv) $ python build_database.py
+(venv) $ python init_database.py
 ```
 
-This will delete any existing database and create a new database named `people.db` that you can use with your project.
+This will create or update the `people.db` database that you can use with your project.
 
 After building the database, you can start the Flask server:
 

…tend/source_code_start/build_database.py …ntend/source_code_start/init_database.pybuild-a-rest-api-frontend/source_code_start/build_database.py renamed to build-a-rest-api-frontend/source_code_start/init_database.py build-a-rest-api-frontend/source_code_start/build_database.py renamed to build-a-rest-api-frontend/source_code_start/init_database.py

@@ -1,4 +1,6 @@
 from datetime import datetime
+from sqlalchemy.exc import OperationalError
+from sqlalchemy.ext.serializer import loads, dumps
 
 from config import app, db
 from models import Note, Person
@@ -43,8 +45,15 @@
     },
 ]
 
-with app.app_context():
-    db.drop_all()
+def get_data_from_table(model):
+    try:
+        data = db.session.query(model).all()
+        db.session.close()
+        return data
+    except OperationalError:
+        return []
+
+def create_database(db):
     db.create_all()
     for data in PEOPLE_NOTES:
         new_person = Person(lname=data.get("lname"), fname=data.get("fname"))
@@ -59,3 +68,26 @@
             )
         db.session.add(new_person)
     db.session.commit()
+    print("Created new database")
+
+def update_database(db, existing_people, existing_notes):
+    db.drop_all()
+    db.create_all()
+    for person in existing_people:
+        db.session.merge(person)
+    for note in existing_notes:
+        db.session.merge(note)
+    db.session.commit()
+    print("Updated existing database")
+
+with app.app_context():
+    existing_people = get_data_from_table(Person)
+    existing_notes = get_data_from_table(Note)
+
+    if not existing_people:
+        create_database(db)
+    else:
+        update_database(db, existing_people, existing_notes)
+
+
+

…nd/source_code_working/build_database.py …end/source_code_working/init_database.pybuild-a-rest-api-frontend/source_code_working/build_database.py renamed to build-a-rest-api-frontend/source_code_working/init_database.py build-a-rest-api-frontend/source_code_working/build_database.py renamed to build-a-rest-api-frontend/source_code_working/init_database.py

@@ -1,4 +1,6 @@
 from datetime import datetime
+from sqlalchemy.exc import OperationalError
+from sqlalchemy.ext.serializer import loads, dumps
 
 from config import app, db
 from models import Note, Person
@@ -43,8 +45,15 @@
     },
 ]
 
-with app.app_context():
-    db.drop_all()
+def get_data_from_table(model):
+    try:
+        data = db.session.query(model).all()
+        db.session.close()
+        return data
+    except OperationalError:
+        return []
+
+def create_database(db):
     db.create_all()
     for data in PEOPLE_NOTES:
         new_person = Person(lname=data.get("lname"), fname=data.get("fname"))
@@ -59,3 +68,26 @@
             )
         db.session.add(new_person)
     db.session.commit()
+    print("Created new database")
+
+def update_database(db, existing_people, existing_notes):
+    db.drop_all()
+    db.create_all()
+    for person in existing_people:
+        db.session.merge(person)
+    for note in existing_notes:
+        db.session.merge(note)
+    db.session.commit()
+    print("Updated existing database")
+
+with app.app_context():
+    existing_people = get_data_from_table(Person)
+    existing_notes = get_data_from_table(Note)
+
+    if not existing_people:
+        create_database(db)
+    else:
+        update_database(db, existing_people, existing_notes)
+
+
+