实验7：基于REST API的SDN北向应用实践.

（一）基本要求

1. 编写Python程序，调用OpenDaylight的北向接口实现以下功能
   （1） 利用Mininet平台搭建下图所示网络拓扑，并连接OpenDaylight；

   

   

   （2） 下发指令删除s1上的流表数据。

2. #!/usr/bin/python
   import requests
   from requests.auth import HTTPBasicAuth

   def http_delete(url):
   url= url
   headers = {'Content-Type':'application/json'}
   resp = requests.delete(url, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
   return resp

   if __name__ == "__main__":
   url = 'http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/'
   resp = http_delete(url)
   print(resp.content)

3. （3） 下发硬超时流表，实现拓扑内主机h1和h3网络中断20s。

    

4. # timeout.py
   import requests
   from requests.auth import HTTPBasicAuth
   if __name__ == "__main__":
   url = 'http://127.0.0.1:8181/restconf/config/opendaylight-inventory:nodes/node/openflow:1/flow-node-inventory:table/0/flow/1'
   with open("./timeOut.json") as file:
   str = file.read()
   headers = {'Content-Type': 'application/json'}
   res = requests.put(url, str, headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
   print (res.content)

5. # timeout.json
   {
   "flow": [
   {
   "id": "1",
   "match": {
   "in-port": "1",
   "ethernet-match": {
   "ethernet-type": {
   "type": "0x0800"
   }
   },
   "ipv4-destination": "10.0.0.3/32"
   },
   "instructions": {
   "instruction": [
   {
   "order": "0",
   "apply-actions": {
   "action": [
   {
   "order": "0",
   "drop-action": {}
   }
   ]
   }
   }
   ]
   },
   "flow-name": "flow",
   "priority": "65535",
   "hard-timeout": "20",
   "cookie": "2",
   "table_id": "0"
   }
   ]
   }

6. （4） 获取s1上活动的流表数。
   

   # getflow.py
   import requests
   from requests.auth import HTTPBasicAuth
   if __name__ == "__main__":
   url = 'http://127.0.0.1:8181/restconf/operational/opendaylight-inventory:nodes/node/openflow:1/flow-node-inventory:table/0/opendaylight-flow-table-statistics:flow-table-statistics'
   headers = {'Content-Type': 'application/json'}
   res = requests.get(url,headers=headers, auth=HTTPBasicAuth('admin', 'admin'))
   print (res.content)

7. 编写Python程序，调用Ryu的北向接口实现以下功能
   （1） 实现上述OpenDaylight实验拓扑上相同的硬超时流表下发。

   （2） 参考Ryu REST API的文档，基于VLAN实验的网络拓扑，编程实现相同的VLAN配置。

   

    

    

   提示：拓扑生成后需连接Ryu，且Ryu应能够提供REST API服务