pocketflow/cookbook/pocketflow-streamlit-hitl/README.md

PocketFlow Streamlit Image Generation HITL

Human-in-the-Loop (HITL) image generation application using PocketFlow and Streamlit. Enter text prompts, generate images with OpenAI, and approve/regenerate results.

Features

• Image Generation: Uses OpenAI's gpt-image-1 model to generate images from text prompts
• Human Review: Interactive interface to approve or regenerate images
• State Machine: Clean state-based workflow (initial_input → user_feedback → final)
• PocketFlow Integration: Uses PocketFlow Node and Flow for image generation with built-in retries
• Session State Management: Streamlit session state acts as PocketFlow's shared store
• In-Memory Images: Images stored as base64 strings, no disk storage required

How to Run

1. Set OpenAI API Key:

   export OPENAI_API_KEY="your-openai-api-key"
   

2. Install Dependencies:

   pip install -r requirements.txt
   

3. Run the Streamlit Application:

   streamlit run app.py
   

4. Access the Web UI: Open the URL provided by Streamlit (usually http://localhost:8501).

Usage

1. Enter Prompt: Describe the image you want to generate
2. Generate: Click "Generate Image" to create the image
3. Review: View the generated image and choose:
   • Approve: Accept the image and move to final result
   • Regenerate: Generate a new image with the same prompt
4. Final: View approved image and optionally start over

Files

• app.py: Main Streamlit application with state-based UI
• nodes.py: PocketFlow GenerateImageNode definition
• flow.py: PocketFlow Flow for image generation
• utils/generate_image.py: OpenAI image generation utility
• requirements.txt: Project dependencies
• docs/design.md: System design documentation
• README.md: This file