Restconf Getting Hands-On

In Lab 8, participants dive into practical hands-on exercises focused on Restconf, a RESTful API used for programmable network management. This lab provides participants with the opportunity to actively interact with Restconf-enabled devices using Python scripts or other automation tools. Through hands-on exercises, participants gain experience in crafting Restconf requests, retrieving device information, and making dynamic configurations on Cisco devices using RESTful API principles. This lab reinforces theoretical knowledge with practical application, allowing participants to see firsthand how Restconf can be leveraged to automate network changes. By actively engaging with Restconf in this lab, participants enhance their skills in programmable network management within the Cisco DevNet ecosystem.

Lab:

This lab exercise will get you started with RESTCONF connections, retrieving data, and sending configurations to the network.

Understanding cURL:

The cURL name is a play on words: “Client for URLs” and “cURL URL Request Library.” It’s a simple command-line tool with lots of options for putting together a REST API request.

When using cURL to make REST API method calls, you typically use the following options and arguments:

• -X followed by a request verb such as GET, PUT, POST, PATCH, or DELETE.
• -H followed by a header such as a token to send with the requests.

For example, a GET request is often used to get a list or to get details about a single resource. So lets walk through an example,

Step 1: Use cURL for RESTCONF configuration

1. The following is a sample RESTCONF request to router to check the allowed methods available for restconf configurations

curl -i -k -X "OPTIONS" "https://10.0.0.1:443/restconf/data/Cisco-IOS-XE-native:native/logging/monitor/severity" -H 'Accept: application/yang-data+json' -u 'cisco:cisco'

2. The router will reply with allowed methods available for RESTCONF.

    < HTTP/1.1 200 OK
    Server: nginx
    Date: Wed, 29 Apr 2020 12:40:50 GMT
    Content-Type: text/html
    Content-Length: 0
    Connection: keep-alive
    Allow: DELETE, GET, HEAD, PATCH, POST, PUT, OPTIONS
    Cache-Control: private, no-cache, must-revalidate, proxy-revalidate
    Accept-Patch: application/yang-data+xml, application/yang-data+json
    Pragma: no-cache

3. The following is a sample RESTCONF request to get primary ip address details of configured GigabitEthernet interfaces.

curl -i -k -X "GET" "https://10.0.0.1:443/restconf/data/Cisco-IOS-XE-native:native/interface?fields=GigabitEthernet/ip/address/primary;name" -H 'Accept: application/yang-data+json' -u 'cisco:cisco'

4. The router will reply with allowed methods available for RESTCONF.

HTTP/1.1 200 OK
Server: nginx
Date: Wed, 29 Apr 2020 14:03:46 GMT
Content-Type: application/yang-data+json
Transfer-Encoding: chunked
Connection: keep-alive
Cache-Control: private, no-cache, must-revalidate, proxy-revalidate
Pragma: no-cache

{
  "Cisco-IOS-XE-native:interface": {
    "GigabitEthernet": [
      {
        "ip": {
          "address": {
            "primary": {
              "address": "10.0.0.1",
              "mask": "255.255.255.0"
            }
          }
        }
      },
      {
        "ip": {
          "address": {
            "primary": {
              "address": "10.255.255.1",
              "mask": "255.255.255.0"
            }
          }
        }
      }
    ]
  }
}

5. The following is a sample RESTCONF request to get ip address details of interface GigabitEthernet 2.

curl -i -k -X "GET" "https://10.0.0.1:443/restconf/data/Cisco-IOS-XE-native:native/interface/GigabitEthernet=2/ip" -H 'Accept: application/yang-data+json' -u 'cisco:cisco'

6. The router will reply with allowed methods available for RESTCONF.

HTTP/1.1 200 OK
Server: nginx
Date: Wed, 29 Apr 2020 14:17:34 GMT
Content-Type: application/yang-data+json
Transfer-Encoding: chunked
Connection: keep-alive
Cache-Control: private, no-cache, must-revalidate, proxy-revalidate
Pragma: no-cache

{
  "Cisco-IOS-XE-native:ip": {
    "address": {
      "secondary": [
        {
          "address": "200.0.0.200",
          "mask": "255.0.0.0",
          "secondary": [null]
        }
      ],
      "primary": {
        "address": "10.255.255.1",
        "mask": "255.255.255.0"
      }
    }
  }
}

7. The following is a sample RESTCONF request to get primary ip address of interface GigabitEthernet 1.

curl -i -k -X "GET" "https://10.0.0.1:443/restconf/data/Cisco-IOS-XE-native:native/interface/GigabitEthernet=1/ip/address/primary" -H 'Accept: application/yang-data+json' -u 'cisco:cisco'

8. The router will reply with allowed methods available for RESTCONF.

HTTP/1.1 200 OK
Server: nginx
Date: Wed, 29 Apr 2020 14:19:28 GMT
Content-Type: application/yang-data+json
Transfer-Encoding: chunked
Connection: keep-alive
Cache-Control: private, no-cache, must-revalidate, proxy-revalidate
Pragma: no-cache

{
  "Cisco-IOS-XE-native:primary": {
    "address": "10.0.0.1",
    "mask": "255.255.255.0"
  }
}

9. The following is a sample RESTCONF request to change hostname.

curl -i -k -X  PUT https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/hostname -H 'Accept: application/yang-data+json' -H 'Content-Type: application/yang-data+json' -H 'cache-control: no-cache' -u 'cisco:cisco' -d '{"hostname": "HelloRST"}'

10. The following is a sample RESTCONF request to change Loopback ip address

curl -i -k -X PATCH https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/interface/Loopback=1/ip/address/primary -H 'Accept: application/yang-data+json' -H 'Content-Type: application/yang-data+json' -H 'cache-control: no-cache' -u 'cisco:cisco' -d '{"primary": {"address": "1.1.1.1", "mask": "255.255.255.0"}}' 

Step 2: Python for RESTCONF configuration

1. The following is a sample RESTCONF request in python to get IP address of loopback 1 interface.

import requests
import urllib3

USER = 'cisco'
PASS = 'cisco'

# disable warnings from SSL/TLS certificates
requests.packages.urllib3.disable_warnings()

url = "https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/interface/Loopback=1/ip/address/primary"

headers = {
    'Accept': "application/yang-data+json",
    'Content-Type': "application/yang-data+json",
    'cache-control': "no-cache",
    }

response = requests.get(url, auth=(USER, PASS),
                            headers=headers, verify=False)
print(response.text)

2. The router will reply as below.

From cffi callback <function _verify_callback at 0x7f4be07c61d0>:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 315, in wrapper
    _lib.X509_up_ref(x509)
AttributeError: 'module' object has no attribute 'X509_up_ref'
{
  "Cisco-IOS-XE-native:primary": {
    "address": "100.200.200.200",
    "mask": "255.255.255.0"
  }
}

3. The following is a sample RESTCONF request in python to get hostname of router.

import requests
import urllib3

USER = 'cisco'
PASS = 'cisco'

# disable warnings from SSL/TLS certificates
requests.packages.urllib3.disable_warnings()

url = "https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/hostname"

payload = ""
headers = {
    'Accept': "application/yang-data+json",
    'Content-Type': "application/yang-data+json",
    'cache-control': "no-cache",
    }

print("----------------------")
print("RSTForum- Configuration Parameters:")
print("----------------------")
response = requests.request("GET",url, auth=(USER, PASS), data=payload,
                            headers=headers, verify=False)

print(response.text)
print("----------------------")
print("RSTForum- Thanks you:")
print("----------------------")

4. The router will reply as below.

{From cffi callback <function _verify_callback at 0x7f87a2192050>:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 315, in wrapper
    _lib.X509_up_ref(x509)
AttributeError: 'module' object has no attribute 'X509_up_ref'
{
  "Cisco-IOS-XE-native:hostname": "RSTForum"
}

5. The following is a sample RESTCONF request in python to post Loopback Ip address.

import requests
import urllib3

USER = 'cisco'
PASS = 'cisco'

# disable warnings from SSL/TLS certificates
requests.packages.urllib3.disable_warnings()

url = "https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/interface/Loopback=1/ip/address/primary"

payload = "{\"primary\": {\"address\": \"88.88.88.88\", \"mask\": \"255.255.255.0\"}}"
headers = {
    'Accept': "application/yang-data+json",
    'Content-Type': "application/yang-data+json",
    'cache-control': "no-cache",
    }

print("----------------------")
print("RSTForum- Configuration Parameters:")
print("----------------------")
response = requests.request("PATCH",url, auth=(USER, PASS), data=payload,
                            headers=headers, verify=False)

print(response.text)
print("----------------------")
print("RSTForum- Thanks you:")
print("----------------------")

6. The router will reply as below.

From cffi callback <function _verify_callback at 0x7fa0034951d0>:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 315, in wrapper
    _lib.X509_up_ref(x509)
AttributeError: 'module' object has no attribute 'X509_up_ref'

7. The following is a sample RESTCONF request in python to put hostname.

import requests
import urllib3

USER = 'cisco'
PASS = 'cisco'

# disable warnings from SSL/TLS certificates
requests.packages.urllib3.disable_warnings()

url = "https://10.0.0.1/restconf/data/Cisco-IOS-XE-native:native/hostname"

payload = "{\"hostname\": \"RSTForum\"}"
headers = {
    'Accept': "application/yang-data+json",
    'Content-Type': "application/yang-data+json",
    'cache-control': "no-cache",
    }

8. The router will reply as below.

From cffi callback <function _verify_callback at 0x7fe88bf8d050>:
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/OpenSSL/SSL.py", line 315, in wrapper
    _lib.X509_up_ref(x509)
AttributeError: 'module' object has no attribute 'X509_up_ref'}