Ambari and Resource Manager REST API with Python

[#1]

Pre-requisites

Hortonworks Data Platform 2.5 on CentOS 7.2

Python distribution that comes with HDP 2.5 - Python 2.7.5

Download and install pip

#wget https://bootstrap.pypa.io/get-pip.py

Install add-on package

#pip install requests

Start Python CLI (default version)

#python

Import pre-reqs

>>>import requests

>>>import json

>>>import sys

Environment Variables

Set Ambari domain variable to the IP address or FQDN of your Ambari node.

>>>AMBARI_DOMAIN = '127.0.0.1'

Set Ambari port, Ambari user and password variables to match your specifics.

>>>AMBARI_PORT = '8080'

>>>AMBARI_USER_ID = 'admin'

>>>AMBARI_USER_PW = 'admin'

Set the following variable to the IP address or FQDN of your ResourceManager node.

>>>RM_DOMAIN = '127.0.0.1'

Set Resource Manager port variable

>>>RM_PORT = '8088'

Ambari REST API Call Examples

Let's find Cluster Name, Cluster Version, Stack and Stack Version:

>>>restAPI='/api/v1/clusters'

>>>url="http://"+AMBARI_DOMAIN+":"+AMBARI_PORT+restAPI

>>>r=requests.get(url, auth=(AMBARI_USER_ID, AMBARI_USER_PW))

>>>json_data=json.loads(r.text)

>>>CLUSTER_NAME = json_data["items"][0]["Clusters"]["cluster_name"]

>>>print(CLUSTER_NAME)

>>>CLUSTER_VERSION =json_data["items"][0]["Clusters"]["version"]

>>>print(CLUSTER_VERSION)

>>>STACK = CLUSTER_VERSION.split('-')[0]

>>>print(STACK)

>>>STACK_VERSION = CLUSTER_VERSION.split('-')[1]

>>>print(STACK_VERSION)

>>>CLUSTER_INFO=json_data

>>>print(CLUSTER_INFO)

Let's find HDP stack repository:

>>>restAPI = "/api/v1/stacks/"+STACK+"/versions/"+STACK_VERSION+"/operating_systems/redhat7/repositories/"+CLUSTER_VERSION

>>>url = "http://"+AMBARI_DOMAIN+":"+AMBARI_PORT+restAPI

>>>r= requests.get(url, auth=(AMBARI_USER_ID, AMBARI_USER_PW))

>>>json_data=json.loads(r.text)

>>>print(json_data)

>>>REPOSITORY_NAME=json_data["Repositories"]["latest_base_url"]

>>>print(REPOSITORY_NAME)

A more elegant approach is to create utility functions. See my repo: https://github.com/cstanca1/HDP-restAPI/

restAPIFunctions.py script in the repo defines a number of useful functions that I have collected over time.

Run restAPIFunctions.py

The same example presented above can now be implemented with a single line call to get CLUSTER_NAME, CLUSTER_VERSION and CLUSTER_INFO using getClusterVersionAndName() function:

>>>CLUSTER_NAME,CLUSTER_VERSION,CLUSTER_INFO = getClusterVersionAndName()
>>>print(CLUSTER_NAME)
>>>print(CLUSTER_VERSION)
>>>print(CLUSTER_INFO)

Resource Manager REST API Call Examples

>>>RM_INFO=getResourceManagerInfo()
>>>RM_SCHEDULER_INFO=getRMschedulerInfo()
>>>print(RM_INFO)
>>>print(RM_SCHEDULER_INFO)

Other Functions

These are other functions included in restAPIFunctions.py script

getServiceActualConfigurations()
getClusterRepository()
getAmbariHosts()
getResourceManagerInfo()
getRMschedulerInfo()
getAppsSummary()
getNodesSummary()
getServiceConfigTypes()
getResourceManagerMetrics()
getCheckClusterForRollingUpgrades()