var errSignatureMismatch = errors.New("Signature does not match")

// When upload object size is greater than 5G in a single PUT/POST operation.
var errDataTooLarge = errors.New("Object size larger than allowed limit")

// When upload object size is less than what was expected.
var errDataTooSmall = errors.New("Object size smaller than expected")

// errServerNotInitialized - server not initialized.

```Python hl_lines="6"
{!../../docs_src/path_operation_advanced_configuration/tutorial003.py!}
```

## Advanced description from docstring

You can limit the lines used from the docstring of a *path operation function* for OpenAPI.

Adding an `\f` (an escaped "form feed" character) causes **FastAPI** to truncate the output used for OpenAPI at this point.

	return target.initOnce.Do(target.initMQTT)
}

func (target *MQTTTarget) initMQTT() error {
	args := target.args

	// Using hex here, to make sure we avoid 23
	// character limit on client_id according to
	// MQTT spec.
	clientID := fmt.Sprintf("%x", time.Now().UnixNano())

	options := mqtt.NewClientOptions().
		SetClientID(clientID).
		SetCleanSession(true).
		SetUsername(args.User).

{!> ../../docs_src/dependencies/tutorial001.py!}
```

////

这些参数就是 **FastAPI** 用来 "处理" 依赖项的。

在两个例子下，都有：

* 一个可选的 `q` 查询参数，是 `str` 类型。
* 一个 `skip` 查询参数，是 `int` 类型，默认值为 `0`。
* 一个 `limit` 查询参数，是 `int` 类型，默认值为 `100`。

在两个例子下，数据都将被转换、验证、在 OpenAPI schema 上文档化，等等。

## 使用它

现在，您可以使用这个类来声明你的依赖项了。

//// tab | Python 3.10+

```Python hl_lines="17"

    from typing import Annotated

    from fastapi import Depends, FastAPI

    app = FastAPI()


    async def common_parameters(q: str | None = None, skip: int = 0, limit: int = 100):
        return {"q": q, "skip": skip, "limit": limit}


    @app.get("/items/")
    async def read_items(commons: Annotated[dict, Depends(common_parameters)]):
        return commons
    ```
    """

	// Total number of completed operations
	ReplicatedCount int64 `json:"replicationCount"`
	// Replication latency information
	Latency ReplicationLatency `json:"replicationLatency"`
	// bandwidth limit for target
	BandWidthLimitInBytesPerSecond int64 `json:"limitInBits"`
	// current bandwidth reported
	CurrentBandwidthInBytesPerSecond float64 `json:"currentBandwidth"`
	// transfer rate for large uploads

			for k := range timeOccurrenceMap {
				if k == nano {
					// We add to ourself later
					continue
				}
				diff := k - nano
				if diff < 0 {
					diff = -diff
				}
				// We are within the limit
				if diff < groupNano {
					timeOccurrenceMap[k]++
				}
			}
		}
		// Add ourself...
		timeOccurrenceMap[nano]++
	}

	maxima = 0 // Counter for remembering max occurrence of elements.

	args := target.args

	db, err := sql.Open("postgres", target.connString)
	if err != nil {
		return err
	}
	target.db = db

	if args.MaxOpenConnections > 0 {
		// Set the maximum connections limit
		target.db.SetMaxOpenConns(args.MaxOpenConnections)
	}

	err = target.db.Ping()
	if err != nil {
		if !(xnet.IsConnRefusedErr(err) || xnet.IsConnResetErr(err)) {

        if (andx != null) {
            this.andx = andx;
            andxCommand = andx.command;
        }
    }

    int getBatchLimit( byte command ) {
        /* the default limit is 0 batched messages before this
         * one, meaning this message cannot be batched.
         */
        return 0;
    }

    /* 
     * We overload this method from ServerMessageBlock because

  // warnings is a list of warning messages to return to the requesting API client.
  // Warning messages describe a problem the client making the API request should correct or be aware of.
  // Limit warnings to 120 characters if possible.
  // Warnings over 256 characters and large numbers of warnings may be truncated.
  // +optional
  repeated string warnings = 7;
}