v3

app.py

 # main application for database task
-from scripts.services.access_functions import db_access_op
+from scripts.core.engine.postgres_connect import cur, postgres_client
+from scripts.services.access_functions import mongo_db_access_op, postgres_db_access_op
+
+# mongodb
+db_choice = input("Enter mongo or postgres")
+if db_choice == 'mongo':
+    print("Mongo DB")
+    mongo_db_access_op()
+else:
+    print("PostgresSQL")
+    result = postgres_db_access_op()
+    if not result:
+        print("Lost in atoms")
+    else:
+        print("Successful")
 
-print("Mongo DB")
-db_access_op()

conf/db.conf

 # database servers
 [connection]
 mongodb = mongodb://localhost:27017
+
+[postgres]
+hostname = localhost
+port = 5432
+dbname = storemanager
+user = postgres
+password = admin
+table_name = products

scripts/config/postgres_connect_config.py

+# postgres connect
+import configparser
+
+conf_postgres = configparser.ConfigParser()
+conf_postgres.read("conf/db.conf")
+
+# read values
+host_name = conf_postgres.get("postgres", "hostname")
+port = conf_postgres.get("postgres", "port")
+dbname = conf_postgres.get("postgres", "dbname")
+user = conf_postgres.get("postgres", "user")
+password = conf_postgres.get("postgres", "password")
+products = conf_postgres.get("postgres", "table_name")

scripts/core/engine/postgres_connect.py

+# postgres db connection
+import psycopg2 as py
+
+from scripts.config.postgres_connect_config import host_name, port, dbname, user, password
+from scripts.constants.file_constants import exception_msg
+
+
+try:
+    postgres_client = py.connect(host=host_name, port=port, user=user, password=password)
+    postgres_client.set_session(autocommit=True)
+
+    # creating cursor for the postgres
+    cur = postgres_client.cursor()
+
+    cur.execute("SELECT datname FROM pg_database WHERE datistemplate = false;")
+
+    # Fetch the result
+    result = cur.fetchall()
+
+    # check if database exist
+    if (dbname,) in result:
+        postgres_client = py.connect(host=host_name, port=port, dbname=dbname, user=user, password=password)
+        postgres_client.set_session(autocommit=True)
+        cur = postgres_client.cursor()
+    else:
+        # end current
+        postgres_client.commit()
+        cur.execute(f'CREATE DATABASE {dbname}')
+except Exception as e:
+    print(f'{exception_msg},{e}')

scripts/core/handlers/postgres_data_del.py

+# deleting data
+# getting user inputs
+from scripts.config.postgres_connect_config import products
+
+
+# user input
+def delete_db_post():
+    field_name = input("Enter the field condition: ")
+    del_data = int(input("Enter the data: "))
+
+    return field_name, del_data
+
+
+# deleting the record
+def db_delete_post(cur, field_name, del_data):
+    return cur.execute(f"DELETE FROM {products} WHERE {field_name} = {del_data}")

scripts/core/handlers/postgres_data_insert.py

+# reading user inputs
+from scripts.config.postgres_connect_config import products
+from scripts.constants.file_constants import exception_msg
+
+
+# user inputs
+def read_inputs_post():
+    p_id = int(input("Enter the product id: "))
+    p_name = input("Enter the product name: ")
+    p_category = input("Enter the category: ")
+    retail_price = int(input("Enter the retail price: "))
+    discount_price = int(input("Enter the discounted price: "))
+    description = input("Enter the product description: ")
+    over_rating = input("Enter the overall rating")
+
+    return p_id, p_name, p_category, retail_price, discount_price, description, over_rating
+
+
+# insert in to table
+def insert_data_post(cur, p_name, p_category, retail_price, discount_price, description, over_rating):
+    try:
+        val_data = [p_name, p_category, retail_price, discount_price, description, over_rating]
+        cur.execute(f"INSERT INTO {products} (Product_Name, Product_Category, Retail_Price, Discounted_Price, "
+                    f"Description, Overall_Rating) VALUES (%s, %s, %s, %s, %s, %s)", val_data)
+    except Exception as e:
+        print(f'{exception_msg},{e}')
+        return False
+    else:
+        return True

scripts/core/handlers/postgres_data_update.py

+# updating the db
+from scripts.config.postgres_connect_config import products
+
+
+# user data
+def input_update_post():
+    field_name = input("Enter the field condition: ")
+    up_data = int(input("Enter the data: "))
+    up_field_name = input("Enter the field to update: ")
+    new_data = input("Enter the new data: ")
+
+    return field_name, up_data, up_field_name, new_data
+
+
+# updating the database
+def db_update_post(cur, field_name, up_data, up_field_name, new_data):
+    return cur.execute(f"UPDATE {products} SET {up_field_name} = '{new_data}' WHERE {field_name} = '{up_data}'")

scripts/core/handlers/postgres_data_view.py

+# view db data
+# display conditions
+import pandas as pd
+
+from scripts.config.postgres_connect_config import products
+
+
+# view the data
+def view_fields_post(cur):
+    cur.execute(f"SELECT * FROM {products}")
+    cursor_data = cur.fetchall()
+    if cursor_data is not None:
+        print("Data collected....")
+        view_data = pd.DataFrame((view_data_record for view_data_record in cursor_data), columns=['Product Id',
+                                                                                                  'Product_Name',
+                                                                                                  'Product_Category',
+                                                                                                  'Retail_Price',
+                                                                                                  'Discounted_Price',
+                                                                                                  'Description',
+                                                                                                  'Overall_Rating'])
+        print(view_data)
+    else:
+        print("Data fetching failed")

scripts/core/handlers/postgres_table_create.py

+# creating a table
+from scripts.config.postgres_connect_config import products
+from scripts.constants.file_constants import exception_msg
+
+
+# create table if exist or not
+def create_table(cur):
+    try:
+        cursor_db = cur
+        cursor_db.execute(f"SELECT * FROM information_schema.tables WHERE table_name = '{products}'")
+        if cursor_db.fetchone():
+            print("Table exist")
+        else:
+            # Create the table if it does not exist
+            cursor_db.execute(f"CREATE TABLE {products} "
+                              f"(Product_Id SERIAL PRIMARY KEY, Product_Name VARCHAR(255),"
+                              f"Product_Category VARCHAR(255),"
+                              f"Retail_Price INT,"
+                              f"Discounted_Price INT,"
+                              f"Description VARCHAR(255),"
+                              f"Overall_Rating INT)")
+    except Exception as e:
+        print(f'{exception_msg},{e}')
+        return False
+    else:
+        return cursor_db

scripts/services/access_functions.py

 # access class functions
 from scripts.services.mongo_db_operations import MongoDbStart
+from scripts.services.postgres_db_operations import PostgresStart
 
 
-def db_access_op():
+# mongo access
+def mongo_db_access_op():
     db_class = MongoDbStart()
     db_created = db_class.mongo_create()
     while True:
@@ -28,3 +30,36 @@ def db_access_op():
             else:
                 print("Thank you....")
                 break
+
+
+# postgres access
+def postgres_db_access_op():
+    db_postgres_class = PostgresStart()
+    create_result = db_postgres_class.post_create()
+    if not create_result:
+        print("Cannot create table")
+        return False
+    while True:
+        try:
+            user_query = input("Enter insert/ update/ delete/ view/ quit : ")
+            if user_query == 'insert':
+                db_postgres_class.post_insert()
+            elif user_query == 'update':
+                db_postgres_class.post_update()
+            elif user_query == 'delete':
+                db_postgres_class.post_delete()
+            elif user_query == 'view':
+                db_postgres_class.post_view()
+            else:
+                db_postgres_class.post_quit()
+                print("Exiting....")
+                break
+        except Exception as e:
+            print("Exception occurred: ", e)
+        else:
+            choice = input("Do you want to continue (yes/no): ")
+            if choice == 'yes':
+                continue
+            else:
+                print("Thank you....")
+                return True

scripts/services/mongo_db_operations.py

@@ -8,6 +8,7 @@ from scripts.core.handlers.view_data_db import view_fields, view_cond
 
 
 class MongoDbStart:
+    # create mongo table
     @staticmethod
     def mongo_create():
         try:
@@ -19,6 +20,7 @@ class MongoDbStart:
             store_manager = db['products']
         return store_manager
 
+    # mongo data insert
     @staticmethod
     # getting input and insert into db
     def mongo_insert(db):
@@ -36,6 +38,7 @@ class MongoDbStart:
         except Exception as e:
             print("Insertion failed", e)
 
+    # mongo update table
     @staticmethod
     def mongo_update(db):
         try:
@@ -48,6 +51,7 @@ class MongoDbStart:
         except Exception as e:
             print(f'{exception_msg}{e}')
 
+    # mongo delete data
     @staticmethod
     def mongo_delete(db):
         try:
@@ -60,6 +64,7 @@ class MongoDbStart:
         except Exception as e:
             print(f'{exception_msg}{e}')
 
+    # mongo view data
     @staticmethod
     def mongo_view(db):
         try:

scripts/services/postgres_db_operations.py

+# class for postgresSql
+from scripts.constants.file_constants import exception_msg
+from scripts.core.engine.postgres_connect import cur, postgres_client
+from scripts.core.handlers.postgres_data_del import delete_db_post, db_delete_post
+from scripts.core.handlers.postgres_data_insert import read_inputs_post, insert_data_post
+from scripts.core.handlers.postgres_data_update import input_update_post, db_update_post
+from scripts.core.handlers.postgres_data_view import view_fields_post
+from scripts.core.handlers.postgres_table_create import create_table
+
+
+class PostgresStart:
+    @staticmethod
+    def post_create():
+        try:
+            client_cursor = cur
+            check_result = create_table(client_cursor)
+            if not check_result:
+                return False
+            else:
+                return check_result
+        except Exception as e:
+            print(f'{exception_msg}{e}')
+
+    @staticmethod
+    def post_insert():
+        try:
+            num_prod = int(input("Enter the number of products: "))
+            while num_prod > 0:
+                p_id, p_name, p_category, retail_price, discount_price, description, over_rating = read_inputs_post()
+                insert_check = insert_data_post(cur, p_name,
+                                                p_category, retail_price, discount_price, description, over_rating)
+                if insert_check:
+                    print("Data inserted....")
+                    num_prod -= 1
+                else:
+                    print("Something went wrong data cannot be inserted....")
+        except Exception as e:
+            print("Insertion failed", e)
+
+    @staticmethod
+    def post_update():
+        try:
+            field_name, up_data, up_field_name, new_data = input_update_post()
+            update_check = db_update_post(cur, field_name, up_data, up_field_name, new_data)
+            if update_check is None:
+                print("Data updated")
+            else:
+                print("Data not updated")
+        except Exception as e:
+            print(f'{exception_msg},{e}')
+
+    @staticmethod
+    def post_delete():
+        try:
+            field_name, del_data = delete_db_post()
+            del_check = db_delete_post(cur, field_name, del_data)
+            if del_check is None:
+                print("Data deleted")
+            else:
+                print("Data not deleted")
+        except Exception as e:
+            print(f'{exception_msg}{e}')
+
+    @staticmethod
+    def post_view():
+        try:
+            view_fields_post(cur)
+
+        except Exception as e:
+            print(f'{exception_msg}{e}')
+
+    @staticmethod
+    def post_quit():
+        # Close the cursor and connection
+        cur.close()
+        postgres_client.close()