# 服务器发送事件（SSE） { #server-sent-events-sse }

你可以使用**服务器发送事件**（SSE）向客户端流式发送数据。

这类似于[流式传输 JSON Lines](stream-json-lines.md)，但使用 `text/event-stream` 格式，浏览器原生通过 [`EventSource` API](https://developer.mozilla.org/en-US/docs/Web/API/EventSource) 支持。

/// info | 信息

新增于 FastAPI 0.135.0。

///

## 什么是服务器发送事件？ { #what-are-server-sent-events }

SSE 是一种通过 HTTP 从服务器向客户端流式传输数据的标准。

每个事件是一个带有 `data`、`event`、`id` 和 `retry` 等“字段”的小文本块，以空行分隔。

	ErrSyntax        = DecoderError{msg: "invalid character"}
	ErrUnexpectedEOF = DecoderError{msg: "unexpected end of JSON input"}
	ErrMaxDepth      = DecoderError{msg: "maximum recursion depth exceeded"}
)

type errPos [2]int // line number, byte offset where error occurred

// DecoderError contains a detailed decoding error.
type DecoderError struct {
	msg       string // description of error
	context   string // additional error context

Some text

```python
# This is a sample Python code block
def hello_world():
    # Comment with indentation
    print("Hello, world!")  # Print greeting
```

Some more text

```toml
# Extra line
# This is a sample TOML code block
title = "TOML Example"  # Title of the document
```

And more text

```console
// Use the command "live" and pass the language code as a CLI argument

        try {
            return CommonsCliEncryptOptions.parse(context.parserRequest.args().toArray(new String[0]));
        } catch (ParseException e) {
            throw new IllegalArgumentException("Failed to parse command line options: " + e.getMessage(), e);
        }
    }

MinIO now supports starting the server arguments and configuration via a YAML configuration file. This YAML configuration describes everything that can be configured in a MinIO setup, such as '--address', '--console-address' and command line arguments for the MinIO server.

# 流式数据 { #stream-data }

如果你要流式传输可以结构化为 JSON 的数据，你应该[流式传输 JSON Lines](../tutorial/stream-json-lines.md)。

但如果你想流式传输纯二进制数据或字符串，可以按下面的方法操作。

/// info | 信息

自 FastAPI 0.134.0 起新增。

///

## 使用场景 { #use-cases }

如果你想流式传输纯字符串，例如直接来自某个 AI LLM 服务的输出，可以使用它。

你也可以用它来流式传输大型二进制文件，在读取的同时按块发送，无需一次性把所有内容读入内存。

你还可以用这种方式流式传输视频或音频，甚至可以在处理的同时生成并发送。

## 使用 `yield` 的 `StreamingResponse` { #a-streamingresponse-with-yield }

$ echo "no" | avdmanager --verbose create avd --force --name "pixel5" --device "pixel" --package "system-images;android-29;google_apis;x86" --tag "google_apis" --abi "x86"
```

2. Run an Emulator using Android Studio or from command line.

```
$ emulator -no-window -no-snapshot-load @pixel5
```

2. Turn on logs with logcat

```

#
# 1. RUN, TEST, OR BUILD BAZEL TARGET(S) WITHIN A TFCI ENVIRONMENT
#    To use:
#       export TFCI=ci/official/envs/env_goes_here
#       export TF_ANY_TARGETS="quoted list of targets, like on the command line"
#       export TF_ANY_MODE="test" or "build" or "run" (default: "test")
#       ./any.sh
#
# 2. RUN ANY OTHER SCRIPT AND ENV WITH NO SIDE EFFECTS (NO UPLOADS)
#    To use:

///

---

Imagine you are the computer / program 🤖 in that story.

While you are at the line, you are just idle 😴, waiting for your turn, not doing anything very "productive". But the line is fast because the cashier is only taking the orders (not preparing them), so that's fine.

#             ; where=[condition for select]; orderBy=[column-name for ordering]
#             ; exceptCodeList=[the list of except code]
#         }
#     }
# }
#
# *The line that starts with '#' means comment-out.
#
map:{
    # example for implicit classification
    #; Flg = list:{
    #    ; map:{topComment=general boolean classification for every flg-column; codeType=Number}