Question

我为我的REST API编写了以下POST方法，该方法是使用Flask构建的。该方法接收一个参数，即一个无线电台网址。

@app.route('/todo/api/v1.0/predvajaj', methods=['POST'])
def create_task():
    print "Expression value: " + str(not request.json or not 'title' in request.json)
    if not request.json or not 'title' in request.json:
        abort(400)

    link=request.json['title']
    print "Link value: " + link
    cmd = "pkill sox"
    os.system(cmd)
    time.sleep(2)   
    #link = "http://www.radiostationurl.m3u"
    cmd = "sox -t mp3 " + link + " -t wav -r 22050 -c 1 - | sudo ../pifm - 90.5 &"
    os.system(cmd)
    return jsonify({'status': "ok"}), 201

API在Raspberry Pi上运行，IP地址为：192.168.0.200。我尝试使用curl工具在本地（在Pi上）测试方法。这很好用：

curl -i -H "Content-Type: application/json" -X POST -d '{"title":"http://www.radiostationurl.m3u"}' http://192.168.0.200:5000/todo/api/v1.0/predvajaj

然后我尝试使用相同的LAN 使用相同的命令和工具在计算机（运行Windows）上测试它，但是我收到以下错误：

HTTP/1.0 400 BAD REQUEST
Content-Type: text/html
Content-Length: 192
Server: Werkzeug/0.10.4 Python/2.7.3
Date: Wed, 05 Aug 2015 11:06:05 GMT

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>400 Bad Request</title>
<h1>Bad Request</h1>
<p>The browser (or proxy) sent a request that this server could not understand.</p>

Webserver输出（两个请求 - 一个来自pi和另一个来自PC）：

Expression value: False
192.168.0.200 - - [05/Aug/2015 11:05:56] "POST /todo/api/v1.0/predvajaj           HTTP/1.1" 201 -
sox WARN wav: Length in output .wav header will be wrong since can't seek to fix it

192.168.0.103 - - [05/Aug/2015 11:06:05] "POST /todo/api/v1.0/predvajaj HTTP/1.1" 400

所以问题在于if表达式的评估。任何人都可以告诉我为什么没有评估？

编辑：尝试使用-v开关运行curl @meuh建议。内容长度不同。

裨：

* About to connect() to 192.168.0.200 port 5000 (#0)
*   Trying 192.168.0.200...
* connected
* Connected to 192.168.0.200 (192.168.0.200) port 5000 (#0)
> POST /todo/api/v1.0/predvajaj HTTP/1.1
> User-Agent: curl/7.26.0
> Host: 192.168.0.200:5000
> Accept: */*
> Content-Type: application/json
> Content-Length: 51
>
* upload completely sent off: 51 out of 51 bytes
* additional stuff not fine transfer.c:1037: 0 0
* additional stuff not fine transfer.c:1037: 0 0
* additional stuff not fine transfer.c:1037: 0 0
* HTTP 1.0, assume close after body
< HTTP/1.0 201 CREATED
< Content-Type: application/json
< Content-Length: 27
< Server: Werkzeug/0.10.4 Python/2.7.3
< Date: Wed, 05 Aug 2015 13:49:01 GMT
<
{
  "status": "predvajam"
* Closing connection #0
}

视窗：

* About to connect() to 192.168.0.200 port 5000 (#0)
*   Trying 192.168.0.200...
* Connected to 192.168.0.200 (192.168.0.200) port 5000 (#0)
> POST /todo/api/v1.0/predvajaj HTTP/1.1
> Host: 192.168.0.200:5000
> User-Agent: curl/7.43.0
> Accept: */*
> Content-Type: application/json
> Content-Length: 49
>
* upload completely sent off: 49 out of 49 bytes
* HTTP 1.0, assume close after body
< HTTP/1.0 400 BAD REQUEST
< Content-Type: text/html
< Content-Length: 192
< Server: Werkzeug/0.10.4 Python/2.7.3
< Date: Wed, 05 Aug 2015 13:50:51 GMT
<
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
<title>400 Bad Request</title>
<h1>Bad Request</h1>
<p>The browser (or proxy) sent a request that this server could not understand.</p>
* Closing connection 0

Answer 1

我在site with the tutorial上忽略了有关此问题的说明，其中说：

注意：如果你在Windows上并使用bash的Cygwin版curl，那么上面的命令就可以了。但是，如果您在常规命令提示符下使用curl的本机版本，则需要执行一些小动作以在请求正文中发送双引号。基本上在Windows上，您必须使用双引号括起请求的主体，然后在其中通过按顺序编写其中三个来转义双引号。

在我的情况下，正确的命令是：

curl -i -H "Content-Type: application/json" -X POST -d "{"""title""":"""http://www.radiostationurl.m3u"""}" http://192.168.0.200:5000/todo/api/v1.0/predvajaj

使用curl在不同的操作系统中调用Flask REST服务方法

1 个答案: