ChatGPT - 파이썬 flask연동 리스트 출력

[질문]
파이썬으로 웹사이트 만들어줘 내용은 hello world 찍어줘
Make a website with Python. The content is, "Hello world". Please film it.

 

[답변]
As an AI language model, I do not have the ability to film videos. However, I can provide you with the code to create a basic "Hello World" website using Python and Flask:

First, make sure you have Flask installed. You can do this by running the command: pip install flask

Create a new Python file called app.py and add the following code:

 

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'
Save the file and run it by running the command python app.py

Open up your web browser and go to http://localhost:5000/. You should see the message "Hello, World!" displayed on the page.

That's it! You now have a basic "Hello World" website up and running.

[에러]
PS D:\python> & C:/Users/jiung/AppData/Local/Microsoft/WindowsApps/python3.10.exe d:/python/web_1.py
Traceback (most recent call last):
  File "d:\python\web_1.py", line 1, in <module>
    from flask import Flask
ModuleNotFoundError: No module named 'flask'

 

Flask는 뭐지?
Micro Web Framework 뭐, 이렇게 말하면 너무 어려우니까, 간단한 웹 사이트, 혹은 간단한 API 서버를 만드는 데에 특화되어있는 Python Web Framework 입니다.

 

[장점]
가볍다! (Python, HTML + CSS + Javascript만 할 줄 알면 금방 배운다!)
배포 편의성 (virtualenv에 Flask 깔고 바로 배포하면 됨!)

[단점]
Django 에 비해서 자유도는 높으나, 제공해 주는 기능이 덜 하다.
복잡도가 올라가면 해줘야 할 것들이 많다.

 

flask 인스톨

pip install flask

 

실행을 했는데 서버가 먹통이다. 질문을 다시 해봐야겠다.

 

[질문]

How do I know it's done?

 

[답변]
If you followed the steps I provided, you should be able to open a web browser and navigate to http://localhost:5000/ to see the "Hello, World!" message displayed on the page. If you see this message, then your website is working and your Python code is successfully serving the message to your browser.

Additionally, in your terminal or command prompt where you ran the python app.py command, you should see log messages indicating that your Flask app is running and listening for incoming requests on port 5000. If you see these log messages, then your Flask app is up and running as well.

If you encounter any errors or issues, you may want to check your code for typos or syntax errors, and ensure that you have installed Flask properly.

 

[의견]
host와 port 설정하는 부분이 없는 것 같아 추가 질문을 해야겠다.

 

[질문]
Add host and port.

[답변]
To add a specific host and port to your Flask app, you can modify the app.run() line in your app.py file as follows:

from flask import Flask

app = Flask(__name__)

@app.route('/')
def hello_world():
    return 'Hello, World!'

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=8080)

In this example, we've added a conditional statement that checks if the script is being run directly (as opposed to being imported as a module). If it is being run directly, then we call app.run() with two arguments: the host argument is set to '0.0.0.0' which tells Flask to listen on all available network interfaces, and the port argument is set to 8080.

You can change the host and port values to whatever you like, depending on your specific use case.

 

flask

Hello World!

파이썬 flask를 이용해 웹에 Hello World를 띄웠다.

 

여기서 끝나면 재미없지.. 테이블 조회 후 리스트를 출력해 보자

 

[질문]

postgrsql 연결해서 테이블 리스트 출력해 줘
Please connect postgrsql and print out the table list.

 

[답변]

Sure, here are the steps to connect to a PostgreSQL database using Python and print out the table list:

1. First, make sure you have the psycopg2 library installed. You can install it using pip by running the command: pip install psycopg2

2. Next, you'll need to create a PostgreSQL database and table for testing. You can use a tool like pgAdmin or the psql command-line tool to do this.

3. Once you have a database and table set up, you can use the following Python code to connect to the database and retrieve a list of tables:

# establish a connection to the database
conn = psycopg2.connect(
    host="your_host_name",
    database="your_database_name",
    user="your_user_name",
    password="your_password"
)

# create a cursor object to execute SQL commands
cur = conn.cursor()

# execute a command to retrieve a list of tables
cur.execute("SELECT table_name FROM information_schema.tables WHERE table_schema='public'")

# fetch all results and print them out
table_list = cur.fetchall()
print("List of tables in the database:")
for table in table_list:
    print(table[0])

# close the cursor and connection objects
cur.close()
conn.close()

Make sure to replace the host, database, user, and password values with the appropriate credentials for your PostgreSQL database.

 

This code establishes a connection to the database using the psycopg2 library, creates a cursor object to execute SQL commands, executes a SELECT query to retrieve a list of table names, fetches the results, and then prints out the list of tables to the console. Finally, it closes the cursor and connection objects to free up resources.

 

저번 시간 포스팅한 pg 커넥션 부분을 채워 넣고 연결시켜 보자

 

아래와 같이 flask 서버를 실행한 결과이다

좀 더 고도화시키기로 하였다. 파이썬 파일과 html을 분리하고 디자인을 입혀 볼 생각이다.

 

[질문]

Connect postgresql with Python Flask and print the table list on the web page.

[답변]
Sure! Here's an example of how to connect to a PostgreSQL database with Flask and display the table list on a web page:

First, make sure you have the psycopg2 library installed. You can install it using pip by running the command: pip install psycopg2

Next, create a new Flask app in a file called app.py. In this example, we'll assume that you have a PostgreSQL database with a table called users that has columns for id, name, and email.

 

from flask import Flask, render_template
import psycopg2

app = Flask(__name__)

# configure database connection
conn = psycopg2.connect(
    host="your_host_name",
    database="your_database_name",
    user="your_user_name",
    password="your_password"
)

@app.route("/")
def list_tables():
    # create a cursor object to execute SQL commands
    cur = conn.cursor()

    # execute a command to retrieve a list of tables
    cur.execute("SELECT table_name FROM information_schema.tables WHERE table_schema='public'")

    # fetch all results
    table_list = cur.fetchall()

    # close the cursor object
    cur.close()

    # render the table list as an HTML page using a template
    return render_template("table_list.html", tables=table_list)

if __name__ == '__main__':
    app.run()

 

This code creates a Flask app and sets up a database connection using psycopg2. In the list_tables() function, it creates a cursor object and executes a SELECT query to retrieve a list of table names, then fetches the results and closes the cursor. Finally, it renders a template called table_list.html with the table list passed as a parameter.

Create a new file called table_list.html in a templates directory. In this file, add the following code to display the table list on the page:

<!DOCTYPE html>
<html>
  <head>
    <title>List of Tables</title>
  </head>
  <body>
    <h1>List of Tables</h1>
    <ul>
    {% for table in tables %}
      <li>{{ table[0] }}</li>
    {% endfor %}
    </ul>
  </body>
</html>

This template creates an HTML page with a heading and an unordered list of table names. It uses a for loop to iterate over the tables list passed in from the Flask app and display each table name in a list item.

Finally, run the Flask app by running the command python app.py and navigate to http://localhost:5000/ in your web browser to see the table list displayed on the page.

 

 

주소창에 localhost:8080을 실행하면 에러가 출력된다.

[2023-02-14 16:13:25,084] ERROR in app: Exception on / [GET]
Traceback (most recent call last):
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\app.py", line 2525, in wsgi_app    
    response = self.full_dispatch_request()
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\app.py", line 1822, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\app.py", line 1820, in full_dispatch_request
    rv = self.dispatch_request()
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\app.py", line 1796, in dispatch_request
    return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)
  File "d:\python\web_1.py", line 30, in list_tables
    return render_template("/table_list.html", tables=table_list)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\templating.py", line 146, in render_template
    template = app.jinja_env.get_or_select_template(template_name_or_list)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\jinja2\environment.py", line 1081, in get_or_select_template
    return self.get_template(template_name_or_list, parent, globals)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\jinja2\environment.py", line 1010, in get_template
    return self._load_template(name, globals)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\jinja2\environment.py", line 969, in _load_template
    template = self.loader.load(self, name, self.make_globals(globals))
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\jinja2\loaders.py", line 126, in load    
    source, filename, uptodate = self.get_source(environment, name)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\templating.py", line 62, in get_source
    return self._get_source_fast(environment, template)
  File "C:\Users\jiung\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.10_qbz5n2kfra8p0\LocalCache\local-packages\Python310\site-packages\flask\templating.py", line 98, in _get_source_fast
    raise TemplateNotFound(template)
jinja2.exceptions.TemplateNotFound: /table_list.html
127.0.0.1 - - [14/Feb/2023 16:13:25] "GET / HTTP/1.1" 500 -

 

위 문구와 함께 질문했다.

 

[질문]

If I run it, the error comes out as below, do you know what it is?

에러내용~

 

[답변]
The error message suggests that the Jinja2 template /table_list.html was not found, which indicates that the file is not present in the expected location or the path to the file is incorrect.

Make sure the table_list.html file is in the expected location and its path is correct. In this case, it should be located in the templates folder of your Flask application. Also, make sure the file name and extension are spelled correctly.

 

 

 

table_list.html 가 template 폴더에 없어서 경로를 못 찾아 생긴 오류였다.

폴더

template 폴더를 만든 후 table_list.html을 이동시켜 주었다.

비쥬얼스튜디오코드

재실행

 

화면이 뭔가 좀 밋밋하다? 디자인 레이아웃 수정도 요청해야겠다.

 

[질문]
출력된 리스트를 디자인 레이아웃을 입혀서 꾸며줄 수 있어?
Can you decorate the printed list with a design layout?

[답변]
Yes, you can use HTML and CSS to decorate the table list with a design layout. Here's an example of how you can add a simple layout to the table list using Bootstrap:

 

출력되는 결과가 마음에 안 들어 헤더 내용으로 고치고 싶다.

 

table_list.html 수정

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Table List</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
  </head>
  <body>
    <div class="container">
      <h1>Table List</h1>
      <table class="table table-striped">
        <thead>
          <tr>
            <th>Name</th>
          </tr>
        </thead>
        <tbody>
          {% for table in tables %}
            <tr>
              <td>{{ table }}</td>
            </tr>
          {% endfor %}
        </tbody>
      </table>
    </div>
  </body>
</html>

위 소스에서 출력되는 내용 수정을 조금만 하였다.

<!DOCTYPE html>
<html>
  <head>
    <meta charset="utf-8">
    <title>Table List</title>
    <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css">
  </head>
  <body>
    <div class="container">
      <h1>Table List</h1>
      <table class="table table-bordered">
        <thead>
          <tr>
            <th>파일명</th>
            <th>레포트 타입</th>
            <th>생성일시</th>
            <th>생성자아이디</th>
          </tr>
        </thead>
        <tbody>
          {% for table in tables %}
            <tr>
              <td>{{ table[0] }}</td>
              <td>{{ table[1] }}</td>
              <td>{{ table[2] }}</td>
              <td>{{ table[3] }}</td>
            </tr>
          {% endfor %}
        </tbody>
      </table>
    </div>
  </body>
</html>

 

재실행

그럴듯한 리스트 페이지가 하나 만들어졌다.

 

오늘도 보람찬 생존 ^.^