Quickstart
Make sure that you have:
- catalystcentersdk installed if needed:
pip install catalystcentersdk
- catalystcentersdk upgraded if needed:
pip install catalystcentersdk --upgrade
Get your Catalyst Center Access Token
To interact with the Catalyst Center APIs, you must have a Catalyst Center Access Token. A Catalyst Center Access Token is how the Catalyst Center APIs validate access and identify the requesting user.
As a best practice, you can store your Catalyst Center credentials as environment variables in your development or production environment.
By default, catalystcentersdk will look for the following environment variables to create new connection objects:
- CATALYST_CENTER_DEBUG - Tells the SDK whether to log request and response information. Useful for debugging and seeing what is going on under the hood. Defaults to False.
- CATALYST_CENTER_VERSION - Catalyst Center API version to use. Defaults to '3.1.3.0'.
- CATALYST_CENTER_ENCODED_AUTH - It takes priority. It is the
username:password
encoded in base 64. For exampleZGV2bmV0dXNlcjpDaXNjbzEyMyE
which decoded isdevnetuser:Cisco123!
- CATALYST_CENTER_USERNAME - HTTP Basic Auth username.
- CATALYST_CENTER_PASSWORD - HTTP Basic Auth password.
- CATALYST_CENTER_BASE_URL - Prefix the base URL to the individual API endpoint suffixes. Defaults to
https://sandboxdnac2.cisco.com:443
. - CATALYST_CENTER_SINGLE_REQUEST_TIMEOUT - Timeout (in seconds) for RESTful HTTP requests. Defaults to 60.
- CATALYST_CENTER_WAIT_ON_RATE_LIMIT - Enables or disables automatic rate-limit handling. Defaults to True.
- CATALYST_CENTER_VERIFY - Controls whether to verify the server's TLS certificate or not. Defaults to True.
- CATALYST_CENTER_USER_AGENT -The User-Agent identifies the client using the SDK, providing useful data such as the SDK version and operating system. This information helps with debugging and monitoring requests.
However you choose to set it, if you have CATALYST_CENTER_VERSION, CATALYST_CENTER_USERNAME and CATALYST_CENTER_PASSWORD, or CATALYST_CENTER_VERSION and CATALYST_CENTER_ENCODED_AUTH environment variables, you are good to go. catalystcentersdk will use them to create your access token when creating new CatalystCenterAPI objects.
If you don't want to set your credentials as environment variables, you can manually provide them as parameters when creating a CatalystCenterAPI object.
Set credentials as environment variables
There are many places and diverse ways that you can set an environment variable, which can include:
- A setting within your development IDE
- A setting in your container / PaaS service
- A statement in a shell script that configures and launches your app
It can be as simple as setting it in your CLI before running your script.
$ CATALYST_CENTER_USERNAME=your_username_here
$ CATALYST_CENTER_PASSWORD=your_password_here
$ python myscript.py
or putting your credentials in a shell script that you source
when your shell starts up or before your run a script:
$ cat mycredentials.sh
export CATALYST_CENTER_ENCODED_AUTH=your_encoded_auth_here
$ source mycredentials.sh
$ python myscript.py
Create a CatalystCenterAPI "Connection Object"
To make interacting with the Catalyst Center APIs as simple and intuitive as possible, all of the APIs have 'wrapped' underneath a single interface. To get started, import the CatalystCenterAPI class and create an API "connection object".
>>> from catalystcentersdk import CatalystCenterAPI
>>> api = CatalystCenterAPI()
As discussed above, catalystcentersdk defaults to pulling from environment variables to generate your access token. If you do not set those environment variables and try to create a new CatalystCenterAPI object without providing them, the system raises an AccessTokenError (a catalystcentersdkException subclass).
>>> from catalystcentersdk import CatalystCenterAPI
>>> api = CatalystCenterAPI()
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "catalystcentersdk/__init__.py", line 237, in __init__
raise AccessTokenError(error_message)
AccessTokenError: You need an access token to interact with the CatalystCenter
APIs. CatalystCenter uses HTTP Basic Auth to create an access
token. You must provide the username and password or just
the encoded_auth, either by setting each parameter or its
environment variable counterpart (CATALYST_CENTER_USERNAME,
CATALYST_CENTER_PASSWORD, CATALYST_CENTER_ENCODED_AUTH).
If you don't provide a known version and try to create a new CatalystCenterAPI, the system raises a VersionError.
>>> from catalystcentersdk import CatalystCenterAPI
>>> api = CatalystCenterAPI(username='devnetuser', password='Cisco123!', base_url='https://sandboxdnac.cisco.com:443', version='3.1.3.0')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "catalystcentersdk/__init__.py", line 209, in __init__
raise VersionError(error_message)
VersionError: Unknown API version, known versions are 2.3.7.6, 2.3.7.9 and 3.1.3.0.
Use the arguments to manually provide enough information for the HTTP Basic Auth process, when creating a new CatalystCenterAPI connection object.
>>> from catalystcentersdk import CatalystCenterAPI
>>> # Create a CatalystCenterAPI connection object; it uses CatalystCenter sandbox URL and encoded_auth, with CatalystCenter API version 3.1.3.0
>>> api = CatalystCenterAPI(encoded_auth='ZGV2bmV0dXNlcjpDaXNjbzEyMyEK', base_url="https://sandboxdnac.cisco.com:443", version='3.1.3.0')
>>> from catalystcentersdk import CatalystCenterAPI
>>> # Create a CatalystCenterAPI connection object; it uses CatalystCenter username and password, with CatalystCenter API version 3.1.3.0
>>> # The base_url used by default is `from catalystcentersdk.config import DEFAULT_BASE_URL`
>>> api = CatalystCenterAPI(username='devnetuser', password='Cisco123!', base_url="https://sandboxdnac.cisco.com:443", version='3.1.3.0')
This is useful if you are reading authentication credentials from a file or database and/or when you want to create more than one connection object.
>>> from catalystcentersdk import CatalystCenterAPI
>>> kingston_auth = 'ZG5hY2VudGVydXNlcjpDaXNjbzEyMyEK'
>>> london_auth = ('london', 'rcx0cf43!')
>>> kingston_api = CatalystCenterAPI(encoded_auth=kingston_auth, base_url="https://sandboxdnac.cisco.com:443", version='3.1.3.0')
>>> london_api = CatalystCenterAPI(*london_auth, base_url="https://128.107.71.199:443", version='3.1.3.0') # * Unpacks tuple
Certificates
Besides username, password, encoded_auth, base_url, and version, there are other parameters when creating the CatalystCenterAPI, many of them have a default value.
When dealing with certificates, the most important one is the verify
parameter.
To avoid getting errors like the following:
>>> from catalystcentersdk import CatalystCenterAPI
>>> own_api = CatalystCenterAPI(encoded_auth='dXNlcm5hbWU6cGFzc3dvcmQK',
... base_url="https://128.107.71.199:443", version='3.1.3.0')
requests.exceptions.SLError: HTTPSConnectionPool(host='128.107.71.199', port=443):
Max retries exceeded with url: /dna/system/api/v1/auth/token (Caused by
SSLError (SSLCertVerificationError(1, '[SSL: CERTIFICATE_VERIFY_FAILED] certificate
verify failed: self signed certificate in certificate chain (_ssl.c:1076)')))
>>>
Include the verify
parameter and set it to False:
>>> from catalystcentersdk import CatalystCenterAPI
>>> own_api = CatalystCenterAPI(encoded_auth='dXNlcm5hbWU6cGFzc3dvcmQK',
... base_url="https://128.107.71.199:443", version='1.3.0',
... verify=False)
InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate
verification is strongly advised. See: https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings
InsecureRequestWarning)
>>>
You see urllib3
warnings instead. If you want to disable them, the easiest way is with:
>>> import urllib3
>>> urllib3.disable_warnings()
Package Constants
The following are the default values pulled from catalystcentersdk.config and used when creating the connection object.
.. automodule:: catalystcentersdk.config
:members:
:no-undoc-members:
:exclude-members: DEBUG_ENVIRONMENT_VARIABLE, VERSION_ENVIRONMENT_VARIABLE, USERNAME_ENVIRONMENT_VARIABLE, PASSWORD_ENVIRONMENT_VARIABLE, ENCODED_AUTH_ENVIRONMENT_VARIABLE, BASE_URL_ENVIRONMENT_VARIABLE, SINGLE_REQUEST_TIMEOUT_ENVIRONMENT_VARIABLE, WAIT_ON_RATE_LIMIT_ENVIRONMENT_VARIABLE, VERIFY_ENVIRONMENT_VARIABLE, VERIFY_STRING_ENVIRONMENT_VARIABLE
Making API Calls
Now that you have created a CatalystCenterAPI connection object, you are ready to start making API calls.
>>> api.device_onboarding_pnp.get_workflows()[0] # api.pnp.get_workflows()[0] till version 1.3.0
{
'version': 1,
'name': 'test',
'description': '',
'useState': 'Available',
'type': 'Standard',
'addedOn': 1559538796969,
'lastupdateOn': 1560455244769,
'startTime': 0,
'endTime': 0,
'execTime': 0,
'currTaskIdx': 0,
'tasks': [{'taskSeqNo': 0,
'name': 'Config Download',
'type': 'Config',
'startTime': 0,
'endTime': 0,
'timeTaken': 0,
'currWorkItemIdx': 0,
'workItemList': [],
'configInfo': {'configId': '62066037-55cd-4c05-8e09-45674994a274',
'configFileUrl': None,
'fileServiceId': None,
'saveToStartUp': True,
'connLossRollBack': True,
'configParameters': None}}],
'addToInventory': True,
'tenantId': '5bd3634ab2bea0004c3ebb58',
'id': '5cf4ac6c568ecc000779da5c'
}
It really is that easy.
All calls are wrapped as native Python methods like :meth:CatalystCenterAPI.device_onboarding_pnp.get_workflows() <catalystcentersdk.api.v2_1_2.device_onboarding_pnp.DeviceOnboardingPnp.get_workflows>
which gets the workflows details for the pnp - see the Get Workflows API endpoint documentation.
As you can see, we represent the API endpoints using simple terms aligned with the API docs; for example, we represent the /onboarding/pnp-workflow
API endpoint as a device_onboarding_pnp.get_workflows()
method available under the CatalystCenterAPI connection object.
A full list of the available API methods, with their descriptions and parameters, is available in the User API Doc
. A summary of the structure is available for each supported version.
You can easily access and call any of these methods directly from your CatalystCenterAPI connection object:
>>> api.device_onboarding_pnp.get_device_list(limit=1) # api.pnp.get_device_list(limit=1) till version 1.3.0
[{'version': 1,
'deviceInfo': {'serialNumber': '1234567890s',
'name': 'Postname-add',
'pid': 'ws-c9300',
'lastSyncTime': 0,
'addedOn': 1559870763581,
'lastUpdateOn': 1559870763581,
'firstContact': 0,
'lastContact': 0,
'state': 'Unclaimed',
'onbState': 'Not Contacted',
'cmState': 'Not Contacted',
'source': 'User',
'reloadRequested': False,
'aaaCredentials': {'username': '', 'password': ''},
'populateInventory': False,
'stack': False,
'sudiRequired': False,
'validActions': {'editSUDI': True,
'editWfParams': True,
'delete': True,
'claim': True,
'unclaim': True,
'reset': False}},
'workflowParameters': {},
'runSummaryList': [{'timestamp': 1559870763581,
'details': 'User Added Device',
'errorFlag': False}],
'tenantId': '5bd3634ab2bea0004c3ebb58',
'id': '5cf9bd2b568ecc000779da65'}]
Catching Exceptions
If something goes wrong with the API call, the system raises an exception. It raises ApiError exceptions when the Catalyst Center cloud returns an error condition. The error message provides the details.
>>> from catalystcentersdk import CatalystCenterAPI, ApiError
>>> api = CatalystCenterAPI(username='devnetuser', password='Cisco123!')
>>> # The base_url used by default is `from catalystcentersdk.config import DEFAULT_BASE_URL`
>>> task = api.task.get_task_by_operationid(
limit=2,
offset=1,
operation_id='xyz')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "catalystcentersdk/api/task.py", line 584, in get_task_by_operationid
json=payload)
File "catalystcentersdk/restsession.py", line 280, in get
response = self.request('GET', url, erc, params=params, **kwargs)
File "catalystcentersdk/restsession.py", line 236, in request
check_response_code(response, erc)
File "catalystcentersdk/utils.py", line 217, in check_response_code
raise ApiError(response)
catalystcentersdk.exceptions.ApiError: [500] Server Error - errorId=20,
componentName=CRUD executeQuery Failed! errorId=20,componentName=CRUD
executeQuery Failed! Named query not known: task.findTaskByOperationId
>>>
You can catch any errors that are returned by the Catalyst Center cloud by catching ApiError exceptions in a try-except block.
>>> from catalystcentersdk.exceptions import ApiError
>>> try:
... task = api.task.get_task_by_operationid(
... limit=2,
... offset=1,
... operation_id='xyz')
... except ApiError as e:
... print(e)
ApiError: [500] Server Error - errorId=20,componentName=CRUD executeQuery Failed! errorId=20,
componentName=CRUD executeQuery Failed! Named query not known: task.findTaskByOperationId
>>>
catalystcentersdk will also raise various other standard errors (TypeError, ValueError, and so on); however, these errors are usually caused by incorrect use of the package or methods and should be sorted while debugging your app.
Working with Returned Objects
The Catalyst Center cloud returns data objects in JSON format, like so:
[{ "version": 1,
"deviceInfo": { "serialNumber": "1234567890s",
"name": "Postname-add ",
"pid": "ws-c9300 ",
"lastSyncTime": 0,
"addedOn": 1559870763581,
"lastUpdateOn": 1559870763581,
"firstContact": 0,
"lastContact": 0,
"state": "Unclaimed ",
"onbState": "Not Contacted ",
"cmState": "Not Contacted ",
"source": "User ",
"reloadRequested": false,
"aaaCredentials": { "username": "", "password": ""},
"populateInventory": false,
"stack": false,
"sudiRequired": false,
"validActions": { "editSUDI": true,
"editWfParams": true,
"delete": true,
"claim": true,
"unclaim": true,
"reset": false}},
"workflowParameters": {},
"runSummaryList": [{ "timestamp": 1559870763581,
"details": "User Added Device ",
"errorFlag": false}],
"tenantId": "5bd3634ab2bea0004c3ebb58 ",
"id": "5cf9bd2b568ecc000779da65 "}]
Sure, JSON data objects can easily be parsed and represented in Python using dictionaries, but when working with an 'object' wouldn't it be nice to be able to work with it like an object - using native object syntax (like accessing attributes using '.' notation)? dnacentersdk enables you to do just that:
>>> pnp_devices = api.pnp.get_device_list()
>>> pnp_devices[0].id
'5cf9bd2b568ecc000779da65'
>>> pnp_devices[0].deviceInfo.state
'Unclaimed'
>>> pnp_devices[0].deviceInfo.serialNumber
'1234567890s'
Representing and treating Catalyst Center data objects as Python data objects, can really help clean up your code and make coding easier:
You don't need to create variables to hold the data attributes, just use the attributes available underneath the data object.
>>> # Do this >>> api.pnp.get_device_history(serial_number=pnp_devices[0].deviceInfo.serialNumber) {'response': [{'timestamp': 1559870763581, 'details': 'User Added Device', 'errorFlag': False}], 'statusCode': 200} >>> # Instead of this >>> device_serialNumber = pnp_devices[0].deviceInfo.serialNumber >>> api.pnp.get_device_history(serial_number=device_serialNumber) {'response': [{'timestamp': 1559870763581, 'details': 'User Added Device', 'errorFlag': False}], 'statusCode': 200}
When accessing 'optional' attributes, like
pnp_devices[0].workflowParameters.configList
attribute of Catalyst Center PnP object, the response object will returnNone
when the attribute is not present and will return the attribute's value when it is present. This avoids some boiler plate code and/or needless exception handling, when working with optional attributes.>>> # Instead of doing this >>> for d in devices: ... if hasattr(d, 'workflowParameters') and hasattr(d.workflowParameters, 'configList'): ... # Do something with the configList attribute ... pass >>> # Or this >>> try: ... for d in devices: ... # Do something with the configList attribute ... d.workflowParameters.configList ... except AttributeError as e: ... pass >>> # You can do this, which is cleaner >>> for d in devices: ... if d.workflowParameters and d.workflowParameters.configList: ... # Do something with the configList attribute ... pass
It just feels more natural. :-) When iterating through sequences, and working with objects in those sequences (see the next section), working with objects as objects is definitely more Pythonic.
The Zen of Python (
PEP 20
_): "Beautiful is better than ugly." "Simple is better than complex."
The currently modeled CatalystCenter Data Object
with its functions, is available in the User API Doc
.
What if CatalystCenter adds new data attributes? Attribute access will work for the newly added attributes without a package update. catalystcentersdk is written to automatically take advantage of new attributes and data as they are returned.
Configuring Logging for catalystcentersdk
The main catalystcentersdk logger is catalystcentersdk.
Other loggers are catalystcentersdk.exceptions, catalystcentersdk.restsession and catalystcentersdk.api.custom_caller.
The catalystcentersdk adds only the logging.NullHandler following the logging recommendations for libraries.
So you can add your logging handlers according to your needs.
import logging
import warnings
from catalystcentersdk import CatalystCenterAPI
# Another way to disable warnings caused by (verify=False)
warnings.filterwarnings('ignore', message='Unverified HTTPS request')
logger = logging.getLogger('simple_example')
logger.setLevel(logging.DEBUG)
# create console handler and set level to debug
ch = logging.StreamHandler()
# create formatter
formatter = logging.Formatter('%(asctime)s - %(name)s - %(levelname)s - %(message)s')
# add formatter to ch
ch.setFormatter(formatter)
# add ch to logger
logger.addHandler(ch)
ch_ = logging.StreamHandler()
api = CatalystCenterAPI(verify=False, debug=True)
logging.getLogger('catalystcentersdk').addHandler(ch_)
logger.debug('simple message')
api.devices.get_device_list()
Adding API call definitions
Custom caller functions help you:
- Add support for custom API calls.
- Add support for API calls that are/were not documented when the SDK was released.
from catalystcentersdk import api
# Create a CatalystCenterAPI connection object;
# it uses CatalystCenter sandbox URL, username and password, with CatalystCenter API version 3.1.3.0.,
# and requests to verify the server's TLS certificate with verify=True.
api_ = api.CatalystCenterAPI(username="devnetuser",
password="Cisco123!",
base_url="https://sandboxdnac.cisco.com:443",
version='3.1.3.0',
verify=True)
# Add your custom API call to the connection object.
# Define the get_global_credentials function.
# Call it with:
# get_global_credentials('NETCONF')
def get_global_credentials(subtype):
return api_.custom_caller.call_api('GET',
'/dna/intent/api/v1/global-credential',
params={
'credentialSubType': subtype
})
# Add your custom API call to the connection object.
# Define the delete_global_credentials_by_id function
# under the custom_caller wrapper.
# Call it with:
# api_.custom_caller.delete_global_credentials_by_id('be456g16-14fd-4cac-94b7-ac3b8f9f')
api_.custom_caller.add_api('delete_global_credentials_by_id',
lambda global_credential_id:
api_.custom_caller.call_api(
'DELETE',
'/dna/intent/api/v1/global-credential/${credentialId}',
path_params={
'credentialId': global_credential_id,
})
)
# Advance usage example using Custom Caller functions.
def setup_custom():
"""
Defines the get_global_credentials and create_netconf_credentials functions
under the custom_caller wrapper, and with help documentation
in two different ways.
Check that they have been added with
'get_global_credentials' in dir(api_.custom_caller)
'create_netconf_credentials' in dir(api_.custom_caller)
Quickly check that you indeed have them as functions with
type(getattr(api_.custom_caller, 'create_netconf_credentials'))
type(getattr(api_.custom_caller, 'create_netconf_credentials'))
Check the documentation with
help(api_.custom_caller.get_global_credentials)
help(api_.custom_caller.create_netconf_credentials)
"""
# Alternative 1: Definition with helper function.
def _get_global_credentials(credential_type):
"""Custom global credential API call, returns response attribute
Args:
credential_type(str): Credential type as CLI
/ SNMPV2_READ_COMMUNITY /
SNMPV2_WRITE_COMMUNITY / SNMPV3 /
HTTP_WRITE / HTTP_READ / NETCONF.
Returns:
MyDict: JSON response. Access the object's properties by using
the dot notation or the bracket notation.
"""
return api_.custom_caller.call_api(
'GET',
'/dna/intent/api/v1/global-credential',
params={
'credentialSubType': credential_type
}).response
# Finally add the function as an attribute.
api_.custom_caller.add_api('get_global_credentials', _get_global_credentials)
# Alternative 2: Definition with lambda function.
api_.custom_caller.add_api('create_netconf_credentials',
lambda port:
api_.custom_caller.call_api(
'POST',
'/dna/intent/api/v1/global-credential/netconf',
json=[{
"netconfPort": port
}])
)
# Finally add the documentation
api_.custom_caller.create_netconf_credentials.__doc__ = """
Custom global credential API call to add NETCONF credentials
Receives:
port(string): Netconf port number
Returns: JSON response.
"""
Check out the Custom Caller documentation to begin using it.