之前分享的《如何用postman控制ODL查看和下发流表》毕竟是要操作postman，不方便集成到代码中。借助Python的Requests库，可以方便的完成调用ODL Restful API的PUT操作。

目标

• 通过ODL，在OVS上添加如下的一个group

# ovs-ofctl dump-groups br0 -O openflow13
OFPST_GROUP_DESC reply (OF1.3) (xid=0x2):
 group_id=1,type=all,bucket=weight:0,set_field:00:00:00:00:00:05->eth_dst,set_field:192.168.100.105->ip_dst,output:5,bucket=weight:0,set_field:00:00:00:00:00:06->eth_dst,set_field:192.168.100.106->ip_dst,output:6,bucket=weight:0,set_field:00:00:00:00:00:07->eth_dst,set_field:192.168.100.107->ip_dst,output:7

准备工作

• 运行ODL的Beryllium-SR3版本
• Python 2.7
• Requests :requests==2.2.1
• 通过YangUI填写group所需信息，做PUT操作，抓取PUT的报文

• 获取对应的Json字段

• 将JSON字段存入文件，供后面调用

$ cat odl.json
{
    "group": [
        {
            "group-type": "group-all",
            "group-id": "1",
            "buckets": {
                "bucket": [
                    {
                        "bucket-id": "0",
                        "action": [
                            {
                                "order": "0",
                                "set-field": {
                                    "ethernet-match": {
                                        "ethernet-destination": {
                                            "address": "00:00:00:00:00:05"
                                        }
                                    }
                                }
                            },
                            {
                                "order": "1",
                                "set-field": {
                                    "ipv4-destination": "192.168.100.105/32"
                                }
                            },
                            {
                                "order": "2",
                                "output-action": {
                                    "output-node-connector": "5"
                                }
                            }
                        ]
                    },
                    {
                        "bucket-id": "1",
                        "action": [
                            {
                                "order": "0",
                                "set-field": {
                                    "ethernet-match": {
                                        "ethernet-destination": {
                                            "address": "00:00:00:00:00:06"
                                        }
                                    }
                                }
                            },
                            {
                                "order": "1",
                                "set-field": {
                                    "ipv4-destination": "192.168.100.106/32"
                                }
                            },
                            {
                                "order": "2",
                                "output-action": {
                                    "output-node-connector": "6"
                                }
                            }
                        ]
                    },
                    {
                        "bucket-id": "2",
                        "action": [
                            {
                                "order": "0",
                                "set-field": {
                                    "ethernet-match": {
                                        "ethernet-destination": {
                                            "address": "00:00:00:00:00:07"
                                        }
                                    }
                                }
                            },
                            {
                                "order": "1",
                                "set-field": {
                                    "ipv4-destination": "192.168.100.107/32"
                                }
                            },
                            {
                                "order": "2",
                                "output-action": {
                                    "output-node-connector": "7"
                                }
                            }
                        ]
                    }
                ]
            }
        }
    ]
}

代码实现

• 关键点有两个
  • 'Content-Type':'application/json'
  • Basic Authentication: admin/admin
• 下面是参考代码

$ cat odl_http.py      
#!/usr/bin/env python

import requests
from requests.auth import HTTPBasicAuth

def http_post(url,jstr):
    url= url
    headers = {'Content-Type':'application/json'}
    resp = requests.put(url,jstr,headers=headers,auth=HTTPBasicAuth('admin', 'admin'))
    return resp     
    
if __name__ == "__main__":
    url = 'http://10.10.11.80:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:128983912192/flow-node-inventory:group/1'
    with open('odl.json') as f:
        jstr = f.read()
    resp = http_post(url,jstr)
    print resp.content

• 抓取报文如下

• 在OVS查看，期望的group添加成功

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