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1. Python Web App
• Use a common Python web framework (Flask or FastAPI) running behind Gunicorn.
• The app handles requests to your site and the OpenAI ChatGPT API.
• Integrates your logic for caching static assets and page resources to disk.
2. Frontend
• A simple HTML/JavaScript frontend served by your Python web app.
• A floating “green circle” button triggers a prompt modal that integrates with the ChatGPT API to rewrite or improve highlighted text.
• When the user highlights a portion of text, your JavaScript captures the selection, sends it to the server for rewriting, and then replaces the text on the page.
3. Packaged into a Mobile App
• Progressive Web App (PWA): Use a Service Worker and a manifest to allow installation of the site on any device.
• iOS/Android: Use a WebView-based “wrapper” or a cross-platform toolkit (e.g., React Native, Flutter, Cordova, Capacitor) to load your web app inside a native shell, enabling distribution via the App Store/Google Play.
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2. Python + Gunicorn Setup
Below is a Flask example. You can do similarly with FastAPI.
Project structure (illustrative):
my_app/
├── app.py
├── requirements.txt
├── static/
│ ├── css/
│ ├── js/
│ └── images/
├── templates/
│ └── index.html
├── service_worker.js
├── manifest.json
└── ...
requirements.txt
Flask==2.2.3
gunicorn==20.1.0
openai==0.27.0
app.py
import os
import openai
from flask import Flask, render_template, request, jsonify
app = Flask(__name__)
openai.api_key = os.environ.get("OPENAI_API_KEY")
# Example route for the main page
@app.route("/")
def index():
return render_template("index.html")
# Route for rewriting highlighted text
@app.route("/rewrite", methods=["POST"])
def rewrite():
data = request.json
user_text = data.get("text", "")
# ChatGPT prompt
prompt = f"Please rewrite the following text to improve clarity and grammar:\n\n{user_text}"
try:
response = openai.Completion.create(
model="text-davinci-003",
prompt=prompt,
max_tokens=200,
temperature=0.7
)
rewritten_text = response["choices"][0]["text"].strip()
return jsonify({"rewritten_text": rewritten_text})
except Exception as e:
return jsonify({"error": str(e)}), 500
if __name__ == "__main__":
# Run with Flask for development; production uses Gunicorn
app.run(host="0.0.0.0", port=5000, debug=True)
Running in Production with Gunicorn
# In your project directory:
gunicorn -w 4 -b 0.0.0.0:5000 app:app
• -w 4 means 4 workers. Tweak based on your server resources.
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3. Caching the Website Resources
If you want to cache or “scrape” resources from a target URL and serve them from your Python app, you could:
1. Use requests to download the HTML, CSS, JS, and images from the target URL.
2. Store them in your static/ folder (or in some cache directory).
3. Rewrite references (URLs) in the downloaded HTML/JS/CSS to point to your local resources.
4. Serve them from your Flask or FastAPI routes.
A simplified snippet that might do the caching process:
import requests
import os
def cache_resources(base_url, local_dir="static/"):
# Example: fetch index.html
r = requests.get(base_url)
if r.status_code == 200:
with open(os.path.join(local_dir, "index_cached.html"), "wb") as f:
f.write(r.content)
# Then parse the HTML, find <link href>, <script src>, <img src>, etc.
# Download them similarly and store them in local_dir.
# Update references in the HTML to your local paths.
This approach can become fairly complex with large/complex websites, so you might consider a site-scraping library or headless browser approach (e.g. using Playwright or Selenium) to handle dynamic content.
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4. Frontend Implementation
templates/index.html
Below is a minimalist example that includes:
• A floating green button.
• A modal with a textarea (or it’s triggered automatically upon highlighting).
• JavaScript to call the rewrite API endpoint.
• Basic PWA scaffolding references (manifest.json, service_worker.js).
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8" />
<title>My Python-Powered App</title>
<!-- PWA manifest -->
<link rel="manifest" href="/manifest.json" />
<!-- iOS meta tags, if needed for a better standalone experience -->
<meta name="apple-mobile-web-app-capable" content="yes" />
<meta name="apple-mobile-web-app-status-bar-style" content="black" />
<meta name="apple-mobile-web-app-title" content="My PWA App" />
<!-- Basic styling -->
<link rel="stylesheet" href="{{ url_for('static', filename='css/styles.css') }}">
</head>
<body>
<h1>Welcome to My Python App</h1>
<p>Select some text on this page, then click the green circle to rewrite it.</p>
<!-- The floating green circle -->
<div id="rewrite-button" class="circle-button">Rewrite</div>
<!-- Modal for rewriting text -->
<div id="rewrite-modal" class="modal">
<div class="modal-content">
<textarea id="selected-text" rows="5" cols="50"></textarea>
<button id="send-rewrite">Rewrite</button>
<button id="close-modal">Close</button>
</div>
</div>
<script src="{{ url_for('static', filename='js/app.js') }}"></script>
</body>
</html>
static/css/styles.css
body {
margin: 0;
padding: 2rem;
font-family: Arial, sans-serif;
}
/* Floating circle button at bottom-right corner */
.circle-button {
position: fixed;
right: 2rem;
bottom: 2rem;
width: 60px;
height: 60px;
border-radius: 30px;
background-color: green;
color: white;
display: flex;
align-items: center;
justify-content: center;
cursor: pointer;
}
/* Modal styles */
.modal {
display: none; /* Hidden by default */
position: fixed;
top: 0;
left: 0;
width: 100%;
height: 100%;
z-index: 9999;
background-color: rgba(0,0,0,0.5);
text-align: center;
}
.modal-content {
background-color: #fff;
margin: 10% auto;
padding: 1rem;
width: 80%;
max-width: 600px;
}
static/js/app.js
// Show modal on button click, populate with highlighted text if any.
const rewriteButton = document.getElementById('rewrite-button');
const rewriteModal = document.getElementById('rewrite-modal');
const selectedTextArea = document.getElementById('selected-text');
const sendRewriteButton = document.getElementById('send-rewrite');
const closeModalButton = document.getElementById('close-modal');
// Track user selection
let userSelection = "";
document.onmouseup = () => {
const selection = window.getSelection().toString();
userSelection = selection;
};
rewriteButton.addEventListener('click', () => {
// If there's highlighted text, populate the textarea
if (userSelection) {
selectedTextArea.value = userSelection;
} else {
selectedTextArea.value = "";
}
rewriteModal.style.display = "block";
});
closeModalButton.addEventListener('click', () => {
rewriteModal.style.display = "none";
});
// Call the rewrite endpoint
sendRewriteButton.addEventListener('click', async () => {
const textToRewrite = selectedTextArea.value.trim();
if (!textToRewrite) return;
try {
const response = await fetch('/rewrite', {
method: 'POST',
headers: {'Content-Type': 'application/json'},
body: JSON.stringify({ text: textToRewrite })
});
const data = await response.json();
if (data.rewritten_text) {
// Replace the selected text in the DOM
replaceSelectedText(data.rewritten_text);
}
} catch (error) {
console.error(error);
}
rewriteModal.style.display = "none";
});
// Utility to replace highlighted text in the DOM
function replaceSelectedText(rewritten) {
const selection = window.getSelection();
if (!selection.rangeCount) return;
const range = selection.getRangeAt(0);
range.deleteContents();
range.insertNode(document.createTextNode(rewritten));
}
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5. Making It a PWA
1. Create manifest.json in your project root:
{
"name": "My Python-Powered PWA",
"short_name": "MyPWA",
"start_url": "/",
"display": "standalone",
"background_color": "#ffffff",
"theme_color": "#4CAF50",
"icons": [
{
"src": "/static/images/icon-192.png",
"sizes": "192x192",
"type": "image/png"
},
{
"src": "/static/images/icon-512.png",
"sizes": "512x512",
"type": "image/png"
}
]
}
2. Service Worker (service_worker.js)
const CACHE_NAME = 'my-pwa-cache-v1';
const urlsToCache = [
'/',
'/static/css/styles.css',
'/static/js/app.js',
'/manifest.json',
// Add any other resources or offline page
];
self.addEventListener('install', (event) => {
event.waitUntil(
caches.open(CACHE_NAME).then((cache) => {
return cache.addAll(urlsToCache);
})
);
});
self.addEventListener('fetch', (event) => {
event.respondWith(
caches.match(event.request).then((response) => {
return response || fetch(event.request);
})
);
});
3. Register the Service Worker in your main HTML (e.g., index.html):
<script>
if ('serviceWorker' in navigator) {
window.addEventListener('load', () => {
navigator.serviceWorker.register('/service_worker.js')
.then(() => console.log('Service Worker registered!'))
.catch(err => console.log('Service Worker registration failed: ', err));
});
}
</script>
4. This allows the user to “Install” your website as a PWA on mobile/desktop.
5. Offline caching is handled by the service worker so your static resources will be accessible offline.
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6. Wrapping in a Native Container
Option A: Cordova / Capacitor / Ionic
1. Create a Cordova or Capacitor project:
npm install -g cordova
cordova create MyApp
2. Copy your www assets from your Python project’s build or templates/static folder into cordova/www.
3. Configure the config.xml or Capacitor’s capacitor.config.json with your app name, ID, etc.
4. Add platforms:
cordova platform add ios
cordova platform add android
5. Build for each platform, open with Xcode or Android Studio to finalize.
Option B: React Native (WebView)
• Create a React Native app, embed a <WebView> pointing to your hosted Python server or local files.
Option C: Flutter (WebView)
• Similarly, use Flutter’s webview_flutter plugin to wrap the URL or local offline content.
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7. Submitting to App Stores
1. iOS
• You must have a valid Developer Account.
• Use Xcode to archive and upload the build.
• Provide screenshots, descriptions, icons, etc. in App Store Connect.
2. Android
• You must have a Google Play Developer Account.
• Generate a signed APK or AAB.
• Upload to the Play Console with screenshots, description, etc.
3. PWA
• No “store” required, though you can optionally submit your PWA to the Microsoft Store or others that support PWAs.
• Users can “Install” from mobile browsers directly.
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8. Notes on the ChatGPT Integration
• You will need an OpenAI API key (set as an environment variable or stored securely).
• Make sure to handle usage costs and request volume.
• For rewriting or summarizing text, consider using the ChatGPT (gpt-3.5-turbo) endpoints (OpenAI’s ChatCompletion API) rather than the older Completion endpoint.
• Example with the ChatCompletion endpoint:
import openai
response = openai.ChatCompletion.create(
model="gpt-3.5-turbo",
messages=[
{"role": "system", "content": "You are a helpful rewriting assistant."},
{"role": "user", "content": f"Rewrite this text:\n\n{user_text}"}
]
)
rewritten_text = response["choices"][0]["message"]["content"]
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9. Putting It All Together
1. Start your Python web server locally:
# For dev:
python app.py
# or for production:
gunicorn -w 4 -b 0.0.0.0:5000 app:app
2. Navigate to http://localhost:5000 and test the page rewriting functionality.
3. Add service worker and manifest for PWA. Test installing it from Chrome or Safari.
4. Wrap your web app in a native shell if you need distribution via Apple’s App Store or Google Play.
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Security Considerations
• When letting users highlight and rewrite content, be mindful of cross-site scripting (XSS) issues. Only manipulate text nodes in a sanitized manner.
• Securely store the OpenAI API key (don’t expose it in the frontend).
• For a production environment, use HTTPS (TLS/SSL).
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Conclusion
By combining:
1. A Flask or FastAPI server (fronted by Gunicorn)
2. Local caching/scraping of a target URL’s resources
3. A floating “rewrite” button and highlight-to-rewrite functionality
4. OpenAI’s ChatGPT API
5. PWA service worker + manifest, or a WebView-based mobile wrapper
You can create a deployable app that runs offline for static resources, yet still makes calls to your Python server (and the ChatGPT API) when needed. You can then release this as a PWA, or package it for the iOS App Store / Google Play Store using Cordova, Capacitor, Ionic, React Native, or Flutter wrappers.
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Further References