server load

packages/fastui/src/components/ServerLoad.tsx

@@ -0,0 +1,55 @@
+import { FC, useContext, useEffect, useState } from 'react'
+
+import { ErrorContext } from '../hooks/error'
+import { ReloadContext } from '../hooks/dev'
+import { request } from '../tools'
+import { DefaultLoading } from '../DefaultLoading'
+import { ConfigContext } from '../hooks/config'
+
+import { AnyComp, FastProps } from './index'
+
+export interface ServerLoadProps {
+  type: 'ServerLoad'
+  url: string
+}
+
+export const ServerLoadComp: FC<ServerLoadProps> = ({ url }) => {
+  const [componentProps, setComponentProps] = useState<FastProps | null>(null)
+
+  const { error, setError } = useContext(ErrorContext)
+  const reloadValue = useContext(ReloadContext)
+  const { rootUrl, pathSendMode, Loading } = useContext(ConfigContext)
+
+  useEffect(() => {
+    // setViewData(null)
+    let fetchUrl = rootUrl
+    if (pathSendMode === 'query') {
+      fetchUrl += `?path=${encodeURIComponent(url)}`
+    } else {
+      fetchUrl += url
+    }
+
+    const promise = request({ url: fetchUrl })
+
+    promise
+      .then(([, data]) => setComponentProps(data as FastProps))
+      .catch((e) => {
+        setError({ title: 'Request Error', description: e.message })
+      })
+    return () => {
+      promise.then(() => null)
+    }
+  }, [rootUrl, pathSendMode, url, setError, reloadValue])
+
+  if (componentProps === null) {
+    if (error) {
+      return <></>
+    } else if (Loading) {
+      return <Loading />
+    } else {
+      return <DefaultLoading />
+    }
+  } else {
+    return <AnyComp {...componentProps} />
+  }
+}

packages/fastui/src/components/display.tsx

@@ -1,6 +1,6 @@
 import { FC } from 'react'
 
-import { useCustomRender } from '../hooks/customRender'
+import { useCustomRender } from '../hooks/config'
 import { DisplayChoices, asTitle } from '../display'
 import { unreachable } from '../tools'
 

packages/fastui/src/components/index.tsx

@@ -1,7 +1,7 @@
 import { useContext, FC } from 'react'
 
 import { ErrorContext } from '../hooks/error'
-import { useCustomRender } from '../hooks/customRender'
+import { useCustomRender } from '../hooks/config'
 import { unreachable } from '../tools'
 
 import { AllDivProps, DivComp } from './div'
@@ -21,6 +21,7 @@ import { ModalComp, ModalProps } from './modal'
 import { TableComp, TableProps } from './table'
 import { AllDisplayProps, DisplayArray, DisplayComp, DisplayObject, DisplayPrimitive } from './display'
 import { JsonComp, JsonProps } from './Json'
+import { ServerLoadComp, ServerLoadProps } from './ServerLoad'
 
 export type FastProps =
   | TextProps
@@ -35,6 +36,7 @@ export type FastProps =
   | LinkProps
   | AllDisplayProps
   | JsonProps
+  | ServerLoadProps
 
 export const AnyComp: FC<FastProps> = (props) => {
   const { DisplayError } = useContext(ErrorContext)
@@ -85,6 +87,8 @@ export const AnyComp: FC<FastProps> = (props) => {
         return <DisplayPrimitive {...props} />
       case 'JSON':
         return <JsonComp {...props} />
+      case 'ServerLoad':
+        return <ServerLoadComp {...props} />
       default:
         unreachable('Unexpected component type', type, props)
         return <DisplayError title="Invalid Server Response" description={`Unknown component type: "${type}"`} />

packages/fastui/src/controller.tsx

@@ -1,51 +1,10 @@
-import { useContext, useEffect, useState } from 'react'
+import { useContext } from 'react'
 
-import type { FastUIProps } from './index'
-
-import { FastProps, AnyComp } from './components'
-import { DefaultLoading } from './DefaultLoading'
 import { LocationContext } from './hooks/locationContext'
-import { ErrorContext } from './hooks/error'
-import { request } from './tools'
-import { ReloadContext } from './hooks/dev'
-
-type Props = Omit<FastUIProps, 'defaultClassName' | 'OnError' | 'customRender'>
+import { ServerLoadComp } from './components/ServerLoad'
 
-export function FastUIController({ rootUrl, pathSendMode, loading }: Props) {
-  const [componentProps, setComponentProps] = useState<FastProps | null>(null)
+export function FastUIController() {
   const { fullPath } = useContext(LocationContext)
 
-  const { error, setError } = useContext(ErrorContext)
-  const reloadValue = useContext(ReloadContext)
-
-  useEffect(() => {
-    // setViewData(null)
-    let url = rootUrl
-    if (pathSendMode === 'query') {
-      url += `?path=${encodeURIComponent(fullPath)}`
-    } else {
-      url += fullPath
-    }
-
-    const promise = request({ url })
-
-    promise
-      .then(([, data]) => setComponentProps(data as FastProps))
-      .catch((e) => {
-        setError({ title: 'Request Error', description: e.message })
-      })
-    return () => {
-      promise.then(() => null).catch(() => null)
-    }
-  }, [rootUrl, pathSendMode, fullPath, setError, reloadValue])
-
-  if (componentProps === null) {
-    if (error) {
-      return <></>
-    } else {
-      return <>{loading ? loading() : <DefaultLoading />}</>
-    }
-  } else {
-    return <AnyComp {...componentProps} />
-  }
+  return <ServerLoadComp type="ServerLoad" url={fullPath} />
 }

packages/fastui/src/hooks/config.ts

@@ -0,0 +1,23 @@
+import { createContext, FC, useContext } from 'react'
+
+import type { CustomRender } from '../index'
+
+import { FastProps } from '../components'
+
+interface Config {
+  rootUrl: string
+  // defaults to 'append'
+  pathSendMode?: 'append' | 'query'
+  customRender?: CustomRender
+  Loading?: FC
+}
+
+export const ConfigContext = createContext<Config>({ rootUrl: '' })
+
+export const useCustomRender = (props: FastProps): FC | void => {
+  const { customRender } = useContext(ConfigContext)
+
+  if (customRender) {
+    return customRender(props)
+  }
+}

packages/fastui/src/index.tsx

@@ -1,21 +1,23 @@
-import { ReactNode } from 'react'
+import { FC } from 'react'
 
 import { LocationProvider } from './hooks/locationContext'
 import { FastUIController } from './controller'
 import { ClassNameContext, ClassNameGenerator } from './hooks/className'
 import { ErrorContextProvider, ErrorDisplayType } from './hooks/error'
-import { CustomRender, CustomRenderContext } from './hooks/customRender'
+import { ConfigContext } from './hooks/config'
 import { FastProps } from './components'
 import { DisplayChoices } from './display'
 import { DevReloadProvider } from './hooks/dev'
 
-export type { ClassNameGenerator, CustomRender, ErrorDisplayType, FastProps, DisplayChoices }
+export type { ClassNameGenerator, ErrorDisplayType, FastProps, DisplayChoices }
+
+export type CustomRender = (props: FastProps) => FC | void
 
 export interface FastUIProps {
   rootUrl: string
   // defaults to 'append'
   pathSendMode?: 'append' | 'query'
-  loading?: () => ReactNode
+  Loading?: FC
   DisplayError?: ErrorDisplayType
   classNameGenerator?: ClassNameGenerator
   customRender?: CustomRender
@@ -24,16 +26,16 @@ export interface FastUIProps {
 }
 
 export function FastUI(props: FastUIProps) {
-  const { classNameGenerator, DisplayError, customRender, devMode, ...rest } = props
+  const { classNameGenerator, DisplayError, devMode, ...rest } = props
   return (
     <div className="fastui">
       <ErrorContextProvider DisplayError={DisplayError}>
         <DevReloadProvider enabled={devMode}>
           <LocationProvider>
             <ClassNameContext.Provider value={classNameGenerator ?? null}>
-              <CustomRenderContext.Provider value={customRender ?? null}>
-                <FastUIController {...rest} />
-              </CustomRenderContext.Provider>
+              <ConfigContext.Provider value={rest}>
+                <FastUIController />
+              </ConfigContext.Provider>
             </ClassNameContext.Provider>
           </LocationProvider>
         </DevReloadProvider>

python/demo/main.py

@@ -1,5 +1,6 @@
 from __future__ import annotations as _annotations
 
+import asyncio
 from datetime import date
 from enum import StrEnum
 from typing import Annotated, Literal
@@ -31,7 +32,7 @@ def read_root() -> AnyComponent:
             ),
             c.Modal(
                 title='Modal Title',
-                body=[c.Text(text='Modal Content')],
+                body=[c.ServerLoad(url='/modal')],
                 footer=[c.Button(text='Close', on_click=PageEvent(name='modal'))],
                 open_trigger=PageEvent(name='modal'),
             ),
@@ -47,6 +48,12 @@ class MyTableRow(BaseModel):
     enabled: bool | None = None
 
 
+@app.get('/api/modal', response_model=FastUI, response_model_exclude_none=True)
+async def modal_view() -> AnyComponent:
+    await asyncio.sleep(2)
+    return c.Text(text='Modal Content Dynamic')
+
+
 @app.get('/api/table', response_model=FastUI, response_model_exclude_none=True)
 def table_view() -> AnyComponent:
     return c.Page(
@@ -98,7 +105,7 @@ class MyFormModel(BaseModel):
 
 @app.get('/api/form', response_model=FastUI, response_model_exclude_none=True)
 def form_view() -> AnyComponent:
-    f = c.Page(
+    return c.Page(
         children=[
             c.Heading(text='Form'),
             c.ModelForm[MyFormModel](
@@ -111,8 +118,6 @@ def form_view() -> AnyComponent:
             ),
         ]
     )
-    debug(f)
-    return f
 
 
 @app.post('/api/form')

python/fastui/components/__init__.py

@@ -96,7 +96,17 @@ class Modal(pydantic.BaseModel):
     type: typing.Literal['Modal'] = 'Modal'
 
 
+class ServerLoad(pydantic.BaseModel):
+    """
+    A component that will be replaced by the server with the component returned by the given URL.
+    """
+
+    url: str
+    class_name: extra.ClassName | None = None
+    type: typing.Literal['ServerLoad'] = 'ServerLoad'
+
+
 AnyComponent = typing.Annotated[
-    Text | Div | Page | Heading | Row | Col | Button | Modal | Table | Form | ModelForm | FormField,
+    Text | Div | Page | Heading | Row | Col | Button | Modal | ServerLoad | Table | Form | ModelForm | FormField,
     pydantic.Field(discriminator='type'),
 ]