### What problem does this PR solve?

Add test for document

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

Co-authored-by: liuhua <10215101452@stu.ecun.edu.cn>

### What problem does this PR solve?

_Briefly describe what this PR aims to solve. Include background context
that will help reviewers understand the purpose of the PR._

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

---------

Co-authored-by: Kevin Hu <kevinhu.sh@gmail.com>

### What problem does this PR solve?

Make the document start parsing.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

### What problem does this PR solve?

API: Adds the feature of uploading document.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)