用Bottle开发web程序(二)

Develop web with bottle, Part Two

Posted by XuXinkun on April 7, 2016

返回码

在开发web程序时,除了一些服务器错误等,常常需要自定义返回码,以便告诉用户处理请求的结果或者状态。bottle支持自定义的返回码,可以通过以下几种方式进行实现。

abort

在bottle中,如果需要设置返回错误码,可以简单的通过abort函数来设置。返回内容会是一个带有错误信息的页面。

@route('/abort', method='POST')
def do_abort():
    data = request.body
    data = data.read()
    if data != 'abort':
        abort(400, 'Your request is not abort.')
    return 'abort test.'

试一下:

[root@localhost ~]# curl -g -i 127.0.0.1:9001/abort -X POST -d 'abort'
HTTP/1.0 200 OK
Server: PasteWSGIServer/0.5 Python/2.7.5
Date: Thu, 07 Apr 2016 03:25:52 GMT
Content-Length: 11
Content-Type: text/html; charset=UTF-8

abort test.[root@localhost ~]#
[root@localhost ~]# curl -g -i 127.0.0.1:9001/abort -X POST -d 'test'
HTTP/1.0 400 Bad Request
Server: PasteWSGIServer/0.5 Python/2.7.5
Date: Thu, 07 Apr 2016 03:26:11 GMT
Content-Length: 731
Content-Type: text/html; charset=UTF-8


    <!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">
    <html>
        <head>
            <title>Error: 400 Bad Request</title>
            <style type="text/css">
              html {background-color: #eee; font-family: sans;}
              body {background-color: #fff; border: 1px solid #ddd;
                    padding: 15px; margin: 15px;}
              pre {background-color: #eee; border: 1px solid #ddd; padding: 5px;}
            </style>
        </head>
        <body>
            <h1>Error: 400 Bad Request</h1>
            <p>Sorry, the requested URL <tt>&#039;http://127.0.0.1:9001/abort&#039;</tt>
               caused an error:</p>
            <pre>Your request is not abort.</pre>
        </body>
    </html>

abort函数用起来比较方便,弊端是返回的是页面,比较难于获取具体的出错信息。

abort and error

error函数可以自定义某个error code的返回内容。可以使用abort函数触发该函数。

自定义的error函数的参数是一个HttpError的实例。可以通过error.body获取实例的相关信息。

@route('/code', method='POST')
def do_abort():
    data = request.body
    data = data.read()
    if data != 'code':
        abort(499, 'Your request is not code.')
    return 'code test.'

@error(499)
def error499(error):
    return error.body

试一下:

[root@localhost ~]# curl -g -i 127.0.0.1:9001/code -X POST -d 'test'
HTTP/1.0 499 Unknown
Server: PasteWSGIServer/0.5 Python/2.7.5
Date: Fri, 08 Apr 2016 02:36:04 GMT
Content-Length: 25
Content-Type: text/html; charset=UTF-8

Your request is not code.[root@localhost ~]# 

HttpResponse

另外一种方式就是自己设定实例化一个HttpResponse进行返回。

@route('/httpresponse', method='POST')
def do_httpresponse():
    data = request.body
    data = data.read()
    if data != 'httpresponse':
        return HTTPResponse(body='Your request is not httpresponse.', status=400)
    return 'httpresponse test.'

试一下:

[root@localhost ~]# curl -g -i 127.0.0.1:9001/httpresponse -X POST -d 'test'
HTTP/1.0 400 Bad Request
Server: PasteWSGIServer/0.5 Python/2.7.5
Date: Thu, 07 Apr 2016 03:30:17 GMT
Content-Length: 26
Content-Type: text/html; charset=UTF-8

Your request is not httpresponse.

这种方式比较灵活,而且返回的body同样支持字典的类型。bottle会将其自动转换为json。

@route('/httpresponse', method='POST')
def do_httpresponse():
    data = request.body
    data = data.read()
    if data != 'httpresponse':
        return HTTPResponse(body={'info':'Your request is not httpresponse.'}, status=400)
    return 'httpresponse test.'

试一下:

[root@localhost ~]# curl -g -i 127.0.0.1:9001/httpresponse -X POST -d 'test'
HTTP/1.0 400 Bad Request
Server: PasteWSGIServer/0.5 Python/2.7.5
Date: Thu, 07 Apr 2016 03:34:55 GMT
Content-Length: 38
Content-Type: application/json

{"info": "Your request is not httpresponse."}

完整样例

import sys
from bottle import abort, run, route , request, HTTPResponse, error


@route('/abort', method='POST')
def do_abort():
    data = request.body
    data = data.read()
    if data != 'abort':
        abort(400, 'Your request is not abort.')
    return 'abort test.'

@route('/httpresponse', method='POST')
def do_httpresponse():
    data = request.body
    data = data.read()
    if data != 'httpresponse':
        return HTTPResponse(body='Your request is not abort.', status=400)
        # return HTTPResponse(body={'info':'Your request is not abort.'}, status=400)
    return 'httpresponse test.'

@route('/code', method='POST')
def do_abort():
    data = request.body
    data = data.read()
    if data != 'code':
        abort(499, 'Your request is not code.')
    return 'code test.'

@error(499)
def error499(error):
    return error.body

def main():
    run(server='paste', host='0.0.0.0', port=9001)


if __name__ == "__main__":
    sys.exit(main())