# Bigger Applications - Multiple Files

If you are building an application or a web API, it's rarely the case that you can put everything on a single file.

**FastAPI** provides a convenience tool to structure your application while keeping all the flexibility.

!!! info
    If you come from Flask, this would be the equivalent of Flask's Blueprints.

## An example file structure

Let's say you have a file structure like this:

```
.
├── app

* 📤 📁 `app/internal/` ⏮️ ➕1️⃣ 📁 `__init__.py`, ⚫️ ➕1️⃣ "🐍 📦": `app.internal`.
*  & 📁 `app/internal/admin.py` ➕1️⃣ 🔁: `app.internal.admin`.

<img src="/img/tutorial/bigger-applications/package.svg">

🎏 📁 📊 ⏮️ 🏤:

```
.
├── app                  # "app" is a Python package
│   ├── __init__.py      # this file makes "app" a "Python package"

* 还有一个子目录 `app/internal/` 包含另一个 `__init__.py` 文件，因此它是又一个「Python 子包」：`app.internal`。
* `app/internal/admin.py` 是另一个子模块：`app.internal.admin`。

<img src="https://fastapi.tiangolo.com/img/tutorial/bigger-applications/package.svg">

带有注释的同一文件结构：

```
.
├── app                  # 「app」是一个 Python 包
│   ├── __init__.py      # 这个文件使「app」成为一个 Python 包
│   ├── main.py          # 「main」模块，例如 import app.main

flatbuffer_cc_library(
    name = "schema_fbs_with_mutable",
    srcs = ["schema.fbs"],
    compatible_with = get_compatible_with_portable(),
    flatc_args = [
        "--gen-mutable",
        "--gen-object-api",
    ],
    out_prefix = "mutable/",
)

# Generic schema for inference on device (but with reflections makes bigger).
flatbuffer_cc_library(

    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

## Dependencies for a group of *path operations*

Later, when reading about how to structure bigger applications ([Bigger Applications - Multiple Files](../../tutorial/bigger-applications.md){.internal-link target=_blank}), possibly with multiple files, you will learn how to declare a single `dependencies` parameter for a group of *path operations*.

    {!> ../../../docs_src/dependencies/tutorial006.py!}
    ```

## Dependencies для группы *операций путей*

Позже, читая о том как структурировать большие приложения ([Bigger Applications - Multiple Files](../../tutorial/bigger-applications.md){.internal-link target=_blank}), возможно, многофайловые, вы узнаете как объявить единый параметр `dependencies` для всей группы *операций путей*.

## Глобальный Dependencies

	if err != nil {
		t.Fatal(err)
	}
	defer f.Close()
	defer Remove(f.Name())

	msg := "Programming today is a race between software engineers striving to " +
		"build bigger and better idiot-proof programs, and the Universe trying " +
		"to produce bigger and better idiots. So far, the Universe is winning."

	if err := WriteFile(f.Name(), []byte(msg), 0644); err != nil {
		t.Fatalf("WriteFile %s: %v", f.Name(), err)
	}

	MapBucketCount     = 1 << MapBucketCountBits

	// Maximum key or elem size to keep inline (instead of mallocing per element).
	// Must fit in a uint8.
	// Note: fast map functions cannot handle big elems (bigger than MapMaxElemBytes).
	MapMaxKeyBytes  = 128
	MapMaxElemBytes = 128 // Must fit in a uint8.

		bz2.c[b]++
		bufIndex++
	}

	if origPtr >= uint(bufIndex) {
		return StructuralError("origPtr out of bounds")
	}

	// We have completed the entropy decoding. Now we can perform the
	// inverse BWT and setup the RLE buffer.
	bz2.preRLE = bz2.tt[:bufIndex]
	bz2.preRLEUsed = 0
	bz2.tPos = inverseBWT(bz2.preRLE, origPtr, bz2.c[:])
	bz2.lastByte = -1
	bz2.byteRepeats = 0
	bz2.repeats = 0

Regular Reads will block until data is available, but not wait for a full buffer. 
Writes will block until there is space available and writes bigger than the buffer will wait for reads to make space.

`TryRead` and `TryWrite` are still available for non-blocking reads and writes.