🐘 Add Postgres CRUD

newtoallofthis123 · newtoallofthis123 · commit f3b51a0c2259 · 2023-09-25T21:10:21.000+05:30
diff --git a/projects/CRUD-with-postgresql/README.md b/projects/CRUD-with-postgresql/README.md
@@ -0,0 +1,85 @@
+# CRUD CLI with 🐘 PostgreSQL
+
+Well, this is a simple CRUD CLI with PostgreSQL. I made this project to help others learn more about PostgreSQL driver for Python and how to create beautiful and interactive CLI's with Python.
+
+Well it is basically a book mark manager, you can add, edit, delete and list your bookmarks.
+
+It is called the Query DB btw.
+
+## What you can learn
+
+I highly recommend you try and read through the code.
+As a beginner, it is far easier to read code that is more like what you would write yourself, and this is a good example of that.
+It doesn't use any advanced Python features, and it doesn't use any advanced SQL features either.
+
+So, no classes, confusing context managers, or anything like that.
+Just plain old functions and SQL.
+
+So, if you are a beginner, you can learn:
+
+- Asking better input from the user
+- Using PostgreSQL with Python
+- Creating beautiful and interactive CLI's with Python
+- Create, Read, Update and Delete (CRUD) operations with PostgreSQL
+
+If you find this project useful, please give it's parent a star.
+
+## Screenshot
+
+![Screenshot](assets/screenshot.png)
+
+## Features
+
+1. Easy to use
+2. Interactive
+3. Beautiful
+4. No need to remember SQL commands
+5. Fast and lightweight
+
+## Prerequisites
+
+- Python 3.6 or higher
+- PostgreSQL 9.5 or higher
+
+### Python dependencies
+
+- psycopg2
+- rich
+
+These dependencies are already in the `requirements.txt` file.
+
+### Create a database
+
+We use postgresql as our database, so you need to create a database with any name and enter the credentials in the `creds.json` file.
+
+```bash
+createdb db_name
+```
+
+## How to use
+
+First, you need to install the dependencies:
+
+```bash
+pip install -r requirements.txt
+```
+
+Then, you need to create a `creds.json` file with the following info:
+
+```json
+{
+    "username": "postgres",
+    "password": "password",
+    "host": "127.0.0.1",
+    "port": "5432",
+    "database": "test"
+}
+```
+
+After that, you can run the CLI with:
+
+```bash
+python main.py
+```
+
+It's done! Now you can use the CLI.
diff --git a/projects/CRUD-with-postgresql/assets/screenshot.png b/projects/CRUD-with-postgresql/assets/screenshot.png
diff --git a/projects/CRUD-with-postgresql/creds.json b/projects/CRUD-with-postgresql/creds.json
@@ -0,0 +1,7 @@
+{
+    "username": "joshi",
+    "password": "NoobScience",
+    "host": "127.0.0.1",
+    "port": "5432",
+    "database": "learn_sql"
+}
diff --git a/projects/CRUD-with-postgresql/main.py b/projects/CRUD-with-postgresql/main.py
@@ -0,0 +1,225 @@
+# Author: NoobScience
+# filename: db.py
+# License: MIT
+# 3rd party Modules Used:
+# Rich
+# psycopg2
+
+# Import the necessary modules
+# Rich for formatting
+from rich.console import Console
+from rich.table import Table
+from rich import print
+from rich.text import Text
+from rich.panel import Panel
+from rich.prompt import Prompt, Confirm
+# For working with postgres
+import psycopg2
+from psycopg2 import Error
+import json
+import string
+import random
+console = Console()
+
+try:
+    # Connect to an existing database
+    try:
+        # Get the secrets
+        file = open("creds.json", "r")
+        stuff = file.read()
+        secrets = json.loads(stuff)
+        # We are using the secrets to connect to the database
+        # Although this is very convenient, it is not secure
+        # If you are building something serious, use a more secure method
+        # Like a .env file
+        # The creds.json is only being used to make the code more readable
+        connection = psycopg2.connect(user=str(secrets["username"]),
+                                      password=str(secrets["password"]),
+                                      host=str(secrets["host"]),
+                                      port=str(secrets["port"]),
+                                      database=str(secrets["database"]))
+        
+        # Get the info of the connection using the get_dsn_parameters() method
+        info = connection.get_dsn_parameters()
+    except:
+        console.print(
+            ":red_circle:Sorry, something went wrong! Maybe a wrong credential? Check stuff.json's info correctly")
+
+    # Define a new cursor object by calling the cursor() method
+    # This is the object we use to interact with the database
+    # Think of it as a pointer to a specific place in the database
+    cursor = connection.cursor()
+
+    print(
+        f'{info["user"]} is connected to PostgreSQL server on {info["host"]}:{info["port"]}')
+
+    # Generate hash for assigning to a entry
+    def hash_gen():
+        lower = string.ascii_lowercase
+        upper = string.ascii_uppercase
+        digits = string.digits
+        whole = lower + upper + digits
+        hash_string = random.sample(whole, 8)
+        hash = "".join(hash_string)
+        return hash
+
+    # Check if a table exits, if not create one
+    # We have the following columns in the table
+    # name, url, author, hash, date
+    # The name, url, author have to be filled
+    # Rest is auto generated by the program and the database
+    def check_table():
+        cursor.execute("""
+        CREATE TABLE IF NOT EXISTS dbview(
+            name TEXT NOT NULL,
+            url TEXT NOT NULL,
+            author TEXT,
+            hash TEXT NOT NULL,
+            date TIMESTAMP
+        );
+        """)
+        console.log(":green_circle: Connected to Table :man: dbview")
+
+    # Insert a new entry into the table
+    # The hash is auto generated
+    def insert(name, url, author):
+        cursor.execute(f"""
+        INSERT INTO dbview (name, url, author, hash, date) VALUES ('{name}', '{url}', '{author}', '{str(hash_gen())}', CURRENT_TIMESTAMP)
+        """)
+        search("name", name)
+
+    # View the table using a rich table
+    def table():
+        cursor.execute("SELECT * from dbview")
+        records = cursor.fetchall()
+        try:
+            table = Table(title=Panel(
+                f'Query DB [red]{info["host"]}:{info["port"]}'), show_header=True, header_style="bold green")
+            table.add_column("Name", style="purple", width=20)
+            table.add_column("Url", style="yellow")
+            table.add_column("Author", style="cyan")
+            table.add_column("Hash", style="dim")
+            table.add_column("Date", no_wrap=True, style="dim blue")
+            for record in records:
+                table.add_row(
+                    record[0],
+                    record[1],
+                    record[2],
+                    record[3],
+                    str(record[4])
+                )
+            console.print(table)
+        except:
+            # Some terminals don't support rich
+            print("Name\t\t | URL\t\t | Channel\t\t | Hash\t\t | Date")
+            for record in records:
+                print(
+                    f'{record[0]}\t\t | {record[1]}\t\t | {record[2]}\t\t | {record[3]}\t\t| {str(record[4])}\t\t')
+
+    # Edit a entry in the table
+    def edit(key, value):
+        console.print(
+            "Enter The New Values to Update in the form of a name url channel")
+        new_record = str(Prompt.ask("Enter Here: "))
+        new_records = new_record.split()
+        # Execute the query to update the table
+        cursor.execute(
+            f"UPDATE dbview SET name='{new_records[0]}', url='{new_records[1]}', author='{new_records[2]}' WHERE {key}='{value}'")
+        console.log(":green_circle: Successfully Updated Database")
+        table()
+
+    # Get the hash of a entry
+    def hash():
+        console.print("Enter A Key and Value to get Hash")
+        record_key = str(Prompt.ask("Enter a Key", choices=[
+                         "name", "url", "author", "hash", "date"], default="name"))
+        record_value = str(Prompt.ask("Enter a Value"))
+        cursor.execute(
+            f"SELECT * from dnview WHERE {record_key}='{record_value}'")
+        records = cursor.fetchone()
+        console.print(f"The Hash is {records[3]}")
+
+    # Delete a entry from the table
+    def delete(key, value):
+        table()
+        cursor.execute(f"DELETE from dbview WHERE {key}='{value}'")
+        console.log(":green_circle: Successfully Updated Database")
+        table()
+
+    # Drop the table
+    def drop():
+        console.print(
+            "Are you sure you want to Drop the database? This will delete the whole table")
+        confirmation = Confirm.ask("Are you sure")
+        if confirmation:
+            cursor.execute("DROP table dbview;")
+            console.print(
+                "Dropped Table dbview: Restart the application to start a new main table")
+        else:
+            console.print("Skipped the drop operation")
+
+    # Search the table for a entry
+    # We provide a lot of options to search
+    # You can search by name, url, author, hash
+    # This makes it easy to search for a entry
+    def search(key, value):
+        cursor.execute(f"SELECT * from dbview WHERE {key}='{value}'")
+        records = cursor.fetchall()
+        table = Table(title=Panel(
+            f'Query DB [red]{info["host"]}:{info["port"]}'), show_header=True, header_style="bold green")
+        table.add_column("Name", style="purple", width=20)
+        table.add_column("Url", style="yellow")
+        table.add_column("Channel", style="cyan")
+        table.add_column("Hash", style="dim")
+        table.add_column("Date", no_wrap=True, style="dim blue")
+        for record in records:
+            table.add_row(
+                record[0],
+                record[1],
+                record[2],
+                record[3],
+                str(record[4])
+            )
+        console.print(table)
+    loop = 1
+    # 12 is a rather arbitrary number
+    # I know. But after a while, you don't want the program to run forever
+    while loop != 12:
+        check_table()
+        # Just the normal CRUD operations
+        action = str(Prompt.ask("Enter your name", choices=[
+                     "view", "new", "edit", "delete", "drop", "quit", "hash"], default="view"))
+        if action == "view":
+            table()
+        if action == "new":
+            name = Prompt.ask("Enter the Name")
+            url = Prompt.ask("Enter The URL")
+            author = Prompt.ask("Enter The Author")
+            insert(name, url, author)
+        if action == "delete":
+            record_key = str(Prompt.ask("Enter the key", choices=[
+                             "name", "url", "author", "hash", "date"], default="name"))
+            record_value = str(Prompt.ask("Enter the Value"))
+            delete(record_key, record_value)
+        if action == "drop":
+            drop()
+        if action == "edit":
+            record_key = str(Prompt.ask("Enter the key", choices=[
+                             "name", "url", "author", "hash", "date"], default="name"))
+            record_value = str(Prompt.ask("Enter the Value"))
+            edit(record_key, record_value)
+        if action == "hash":
+            hash()
+        if action == "quit":
+            loop = 12
+
+# If something goes wrong, we catch the error
+except (Exception, Error) as error:
+    print("Error while connecting to PostgreSQL", error)
+# We finally close the connection
+finally:
+    if (connection):
+        connection.commit()
+        cursor.close()
+        connection.close()
+        console.print(":red_heart: Thanks for using db.py")
diff --git a/projects/CRUD-with-postgresql/requirements.txt b/projects/CRUD-with-postgresql/requirements.txt
@@ -0,0 +1,2 @@
+rich==13.5.3
+psycopg2==2.9.7
