Fix demo desc and add test for this

Author: ischaojie

demo/forms.py

@@ -144,7 +144,7 @@ class BigModel(BaseModel):
         None,
         max_length=10,
         min_length=2,
-        description='This field is not required, it must start with a capital letter if provided',
+        description='This field is not required, it must start with a capital letter if provided, and have length 2-10',
     )
     profile_pic: Annotated[UploadFile, FormFile(accept='image/*', max_size=16_000)] = Field(
         description='Upload a profile picture, must not be more than 16kb'
@@ -156,7 +156,7 @@ class BigModel(BaseModel):
     human: bool | None = Field(
         None, title='Is human', description='Are you human?', json_schema_extra={'mode': 'switch'}
     )
-    number: int | None = Field(None, title='Number', ge=0, le=10, multiple_of=2, description='This is a number')
+    number: int | None = Field(None, title='Number', ge=0, le=10, multiple_of=2, description='This is a number should be 0-10 and step with 2')
     size: SizeModel
 
     @field_validator('name')

src/python-fastui/fastui/json_schema.py

@@ -46,6 +46,8 @@ class JsonSchemaString(JsonSchemaBase):
     type: _ta.Required[_t.Literal['string']]
     default: str
     format: _t.Literal['date', 'date-time', 'time', 'email', 'uri', 'uuid', 'password']
+    maxLength: int
+    minLength: int
 
 
 class JsonSchemaStringEnum(JsonSchemaBase, total=False):
@@ -61,6 +63,8 @@ class JsonSchemaStringSearch(JsonSchemaBase, total=False):
     search_url: _ta.Required[str]
     placeholder: str
     initial: SelectOption
+    maxLength: int
+    minLength: int
 
 
 class JsonSchemaFile(JsonSchemaBase, total=False):

src/python-fastui/tests/test_forms.py

@@ -6,14 +6,14 @@
 from fastapi import HTTPException
 from fastui import components
 from fastui.forms import FormFile, fastui_form
-from pydantic import BaseModel
+from pydantic import BaseModel, Field
 from starlette.datastructures import FormData, Headers, UploadFile
 from typing_extensions import Annotated
 
 
 class SimpleForm(BaseModel):
-    name: str
-    size: int = 4
+    name: str = Field(..., max_length=10, min_length=2, description='This field is required, it must have length 2-10')
+    size: int = Field(4, ge=0, le=10, multiple_of=2, description='size with range 0-10 and step with 2')
 
 
 class FakeRequest:
@@ -31,7 +31,7 @@ async def form(self):
 
 def test_simple_form_fields():
     m = components.ModelForm[SimpleForm](submit_url='/foobar/')
-
+    print(m.model_dump(by_alias=True, exclude_none=True))
     assert m.model_dump(by_alias=True, exclude_none=True) == {
         'submitUrl': '/foobar/',
         'method': 'POST',
@@ -44,6 +44,9 @@ def test_simple_form_fields():
                 'locked': False,
                 'htmlType': 'text',
                 'type': 'FormFieldInput',
+                'maxLength': 10,
+                'minLength': 2,
+                'description': 'This field is required, it must have length 2-10',
             },
             {
                 'name': 'size',
@@ -53,6 +56,10 @@ def test_simple_form_fields():
                 'locked': False,
                 'htmlType': 'number',
                 'type': 'FormFieldInput',
+                'ge': 0,
+                'le': 10,
+                'multipleOf': 2,
+                'description': 'size with range 0-10 and step with 2',
             },
         ],
     }
@@ -61,11 +68,11 @@ def test_simple_form_fields():
 async def test_simple_form_submit():
     form_dep = fastui_form(SimpleForm)
 
-    request = FakeRequest([('name', 'bar'), ('size', '123')])
+    request = FakeRequest([('name', 'bar'), ('size', '2')])
 
     m = await form_dep.dependency(request)
     assert isinstance(m, SimpleForm)
-    assert m.model_dump() == {'name': 'bar', 'size': 123}
+    assert m.model_dump() == {'name': 'bar', 'size': 2}
 
 
 async def test_simple_form_submit_repeat():