Right before deciding to build **FastAPI** I found **APIStar** server. It had almost everything I was looking for and had a great design.

It was one of the first implementations of a framework using Python type hints to declare parameters and requests that I ever saw (before NestJS and Molten). I found it more or less at the same time as Hug. But APIStar used the OpenAPI standard.

                    .build());
            options.addOption(Option.builder(CACHE_ARTIFACT_NOT_FOUND)
                    .longOpt("cache-artifact-not-found")
                    .hasArg()
                    .desc(
                            "Defines caching behaviour for 'not found' artifacts. Supported values are 'true' (default), 'false'.")
                    .build());

- 客户端没有执行操作的权限
- 客户端没有访问资源的权限
- 客户端要访问的项目不存在
- 等等 ...

遇到这些情况时，通常要返回 **4XX**（400 至 499）**HTTP 状态码**。

**4XX** 状态码与表示请求成功的 **2XX**（200 至 299） HTTP 状态码类似。

只不过，**4XX** 状态码表示客户端发生的错误。

大家都知道**「404 Not Found」**错误，还有调侃这个错误的笑话吧？

## 使用 `HTTPException`

向客户端返回 HTTP 错误响应，可以使用 `HTTPException`。

### 导入 `HTTPException`

```Python hl_lines="1"
{!../../docs_src/handling_errors/tutorial001.py!}

```

				if err != nil {
					logger.FatalIf(err, "Unable to initialize MinIO server with [%s] invalid entry found in MINIO_PUBLIC_IPS", endpoint)
				}
				for _, addr := range addrs {
					domainIPs.Add(addr)
				}
			}
			domainIPs.Add(endpoint)
		}
		updateDomainIPs(domainIPs)
	} else {
		// Add found interfaces IP address to global domain IPS,
		// loopback addresses will be naturally dropped.

			update, err := testCase.meta.validate(testCase.pools)
			if testCase.expectedErr {
				t.Log(err)
			}
			if err != nil && !testCase.expectedErr {
				t.Errorf("Expected success, but found %s", err)
			}
			if err == nil && testCase.expectedErr {
				t.Error("Expected error, but got `nil`")
			}
			if update != testCase.expectedUpdate {

				return
			}
		default:
			bts, err = msgp.Skip(bts)
			if err != nil {
				err = msgp.WrapError(err)
				return
			}
		}
	}
	o = bts
	return
}

// Msgsize returns an upper bound estimate of the number of bytes occupied by the serialized message
func (z RStat) Msgsize() (s int) {
	s = 1 + 6 + msgp.Int64Size + 6 + msgp.Int64Size
	return
}

// DecodeMsg implements msgp.Decodable

						duration = time.Duration(val) * time.Millisecond
					case ts.Unit.IsSetMICROS():
						duration = time.Duration(val) * time.Microsecond
					default:
						return nil, errors.New("Invalid LogicalType annotation found")
					}
					value = sql.FormatSQLTimestamp(time.Unix(0, 0).Add(duration))
				}
			} else if se.GetConvertedType() == parquettypes.ConvertedType_TIMESTAMP_MILLIS {
				duration := time.Duration(val) * time.Millisecond

// Copyright 2017 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "../../../../../runtime/textflag.h"

TEXT	foo(SB), DUPOK|NOSPLIT, $0

	ADDF	F0, F1, F2    // 002a31ee
	ADDD.EQ	F3, F4, F5    // 035b340e
	ADDF.NE	F0, F2        // 002a321e
	ADDD	F3, F5        // 035b35ee
	SUBF	F0, F1, F2    // 402a31ee
	SUBD.EQ	F3, F4, F5    // 435b340e

// Copyright 2013 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

// The linkcheck command finds missing links in the godoc website.
// It crawls a URL recursively and notes URLs and URL fragments
// that it's seen and prints a report of missing links at the end.
package main

import (
	"errors"
	"flag"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"

                    }
                    break;
                default:
                    if ( log.isDebugEnabled() ) {
                        log.debug("Found unhandled PAC buffer " + bufferType);
                    }
                }
            }
        }
        catch ( IOException e ) {
            throw new PACDecodingException("Malformed PAC", e);
        }