Improve Configuration Usage Experience

[laipz8200]

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1. Is this request related to a challenge you're experiencing? Tell me about your story.

Currently, we have implemented a configuration based on Pydantic. However, we read the configuration through Flask.config or environment variables, which prevents us from utilizing Pydantic’s type system.

I have the following refactoring plan:

1. Create a singleton DifyConfig
2. Use this singleton to replace all logic that currently retrieves values from current_app.config and environment variables
3. Modify any existing mock cases that might be affected

2. Additional context or comments

No response

3. Can you help us with this feature?

• [ ] I am interested in contributing to this feature.

[laipz8200]

Since this refactoring involves a lot of code, we hope to complete it in multiple stages. If you're interested in helping us with this task, please leave a message here.🙏

Refactoring isn't too difficult, and even those who are not yet familiar with Dify can join in. If you're unsure about how to proceed, you can refer to #5938.

Don't be shy, come and get involved!

Current progress

• [ ] api/models - @Poorandy
• [ ] api/core/workflow - @Poorandy
• [ ] api/core/tools - @Poorandy
• [ ] api/core/rag
• [ ] api/core/file
• [ ] api/core/moderation
• [ ] api/core/app
• [ ] api/controllers/console
• [ ] api/controllers/inner_api
• [ ] api/controllers/service_api
• [ ] api/controllers/web
• [ ] api/scheduler
• [ ] api/services
• [ ] api/tasks
• [ ] others

[Poorandy]

I'm in. Just let me know if there's anything I can do.

[laipz8200]

Hi @Poorandy! Thank you for your response. Could you please check the directories api/models, api/core/tools, and api/core/workflow? Please modify the parts where current_app.config is used.

You need to read our Contribution Guide first. Once you are done, please open a pull request and refer to this issue.