Until a connection is established, all outgoing requests will return `ErrDisconnected`.

# Usage

## Single Payload Requests

Single payload requests are requests and responses that are sent in a single message.
In essence, they are `[]byte` -> `[]byte, error` functions.

It is not possible to return *both* an error and a response.

![ReDoc](https://fastapi.tiangolo.com/img/index/index-02-redoc-simple.png)

## Build a Docker Image with a Single-File FastAPI { #build-a-docker-image-with-a-single-file-fastapi }

If your FastAPI is a single file, for example, `main.py` without an `./app` directory, your file structure could look like this:

```
.
├── Dockerfile
├── main.py
└── requirements.txt

<div class="termy">

```console
$ pip install sqlmodel
---> 100%
```

</div>

## Create the App with a Single Model { #create-the-app-with-a-single-model }

We'll create the simplest first version of the app with a single **SQLModel** model first.

Later we'll improve it increasing security and versatility with **multiple models** below. 🤓

### Create Models { #create-models }

/// info

`Body` also has all the same extra validation and metadata parameters as `Query`, `Path` and others you will see later.

///

## Embed a single body parameter { #embed-a-single-body-parameter }

Let's say you only have a single `item` body parameter from a Pydantic model `Item`.

By default, **FastAPI** will then expect its body directly.

	AMOMIND		X5, (X6), X7			// af335386
	AMOMINUW	X5, (X6), X7			// af2353c6
	AMOMINUD	X5, (X6), X7			// af3353c6

	// 20.5: Single-Precision Load and Store Instructions
	FLW	(X5), F0				// 07a00200
	FLW	4(X5), F0				// 07a04200
	FSW	F0, (X5)				// 27a00200
	FSW	F0, 4(X5)				// 27a20200

	// 20.6: Single-Precision Floating-Point Computational Instructions
	FADDS	F1, F0, F2				// 53011000
	FSUBS	F1, F0, F2				// 53011008

* **Harder for non-native speakers**: Contributors and users for whom English is a second language benefit from a single, consistent convention

While both American and British English are valid, establishing a single standard improves consistency, readability, and maintainability of the codebase.

## Decision

Docker Compose allows defining and running single host, multi-container Docker applications.

// The lines yielded by the iterator include their terminating newlines.
// If s is empty, the iterator yields no lines at all.
// If s does not end in a newline, the final yielded line will not end in a newline.
// It returns a single-use iterator.
func Lines(s []byte) iter.Seq[[]byte] {
	return func(yield func([]byte) bool) {
		for len(s) > 0 {
			var line []byte
			if i := IndexByte(s, '\n'); i >= 0 {
				line, s = s[:i+1], s[i+1:]
			} else {

But in most cases, you will want to perform these steps only **once**.

So, you will want to have a **single process** to perform those **previous steps**, before starting the application.

* Memory
* Previous steps before starting

Up to this point, with all the tutorials in the docs, you have probably been running a **server program**, for example, using the `fastapi` command, that runs Uvicorn, running a **single process**.

When deploying applications you will probably want to have some **replication of processes** to take advantage of **multiple cores** and to be able to handle more requests.