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rgba(0,0,0,.075)}input[type=file].error{color:#b94a48;background:0 0;-webkit-box-shadow:none;box-shadow:none}input[type=file].valid{color:#468847;background:0 0;-webkit-box-shadow:none;box-shadow:none}.form-error{display:block;color:#b94a48;margin-top:5px;margin-bottom:10px;line-height:140%}span.help{color:#999;font-size:90%}input.async-validation,input.validating-server-side,select.async-validation,select.validating-server-side{opacity:.5;background-image:url(data:image/gif;base64,R0lGODlhEAAQA...

///

## Create a middleware { #create-a-middleware }

To create a middleware you use the decorator `@app.middleware("http")` on top of a function.

The middleware function receives:

* The `request`.
* A function `call_next` that will receive the `request` as a parameter.
    * This function will pass the `request` to the corresponding *path operation*.

## 掛載一個 **FastAPI** 應用程式 { #mounting-a-fastapi-application }

「掛載」是指在某個特定路徑下加入一個完全「獨立」的應用程式，之後該應用程式會負責處理該路徑底下的一切，使用該子應用程式中宣告的*路徑操作（path operation）*。

### 頂層應用程式 { #top-level-application }

先建立主（頂層）**FastAPI** 應用程式以及它的*路徑操作*：

{* ../../docs_src/sub_applications/tutorial001_py310.py hl[3, 6:8] *}

### 子應用程式 { #sub-application }

接著，建立你的子應用程式及其*路徑操作*。

g"),Pt=["sanitize","whiteList","sanitizeFn"],Lt="fade",Rt="show",xt="show",qt="out",Ft="hover",Qt="focus",Bt={AUTO:"auto",TOP:"top",RIGHT:"right",BOTTOM:"bottom",LEFT:"left"},Ht={animation:!0,template:'<div class="tooltip" role="tooltip"><div class="arrow"></div><div class="tooltip-inner"></div></div>',trigger:"hover focus",title:"",delay:0,html:!1,selector:!1,placement:"top",offset:0,container:!1,fallbackPlacement:"flip",boundary:"scrollParent",customClass:"",sanitize:!0,sanitizeFn:null,whiteLi...

 * }, executor);
 * }
 *
 * <h3>How to get an instance</h3>
 *
 * <p>We encourage you to return {@code ListenableFuture} from your methods so that your users can
 * take advantage of the {@linkplain Futures utilities built atop the class}. The way that you will
 * create {@code ListenableFuture} instances depends on how you currently create {@code Future}
 * instances:
 *
 * <ul>

 * }, executor);
 * }
 *
 * <h3>How to get an instance</h3>
 *
 * <p>We encourage you to return {@code ListenableFuture} from your methods so that your users can
 * take advantage of the {@linkplain Futures utilities built atop the class}. The way that you will
 * create {@code ListenableFuture} instances depends on how you currently create {@code Future}
 * instances:
 *
 * <ul>

	// Now check machine code layout.

	top := pList.Firstpc
	var text *obj.LSym
	ok = true
	ctxt.DiagFunc = func(format string, args ...any) {
		t.Errorf(format, args...)
		ok = false
	}
	obj.Flushplist(ctxt, pList, nil)

	if !ok {
		// If we've encountered errors, the output is unlikely to be sane.
		t.FailNow()
	}

	for p := top; p != nil; p = p.Link {
		if p.As == obj.ATEXT {

type Sub[T Maskable] struct {
	ch     chan T
	types  Mask
	filter func(entry T) bool
}

// PubSub holds publishers and subscribers
type PubSub[T Maskable, M Maskable] struct {
	// atomics, keep at top:
	types          uint64
	numSubscribers int32
	maxSubscribers int32

	// not atomics:
	subs []*Sub[T]
	sync.RWMutex
}

// Publish message to the subscribers.

<la:form action="/search" method="get" styleId="searchForm"
	role="search">
	${fe:facetForm()}${fe:geoForm()}
	<header>
		<nav class="navbar navbar-expand-md navbar-dark fixed-top bg-dark d-print-none">
			<div id="content" class="container">
				<la:link styleClass="navbar-brand d-inline-flex" href="/">
					<img src="${fe:url('/images/logo-head.png')}"
						alt="<la:message key="labels.header_brand_name" />"