View source for Redfish:Accessing Redfish enabled systems using Python

== Introduction ==
* This documents contains preparation on the OS to make redfish runs from the OS command line console.
* One sample python script is provided, with sample output.
* As of this writing, only Red Hat 6.x is supported (tested)
* This document only covers additional steps needed to make redfish run on the OS. It does not cover OS installation instructions.
* This was done on a vanilla CentOS 6.7 installation

== Installation of Chrome Browser ==
* Not actually vital (or even necessary for the following) but is useful for when you have to do individual manual test, launching RESTful API commands, etc
* '''Installation must be done as root'''
<syntaxhighlight>
[root@localhost ~]# cd Downloads/
[root@localhost Downloads]# wget http://chrome.richardlloyd.org.uk/install_chrome.sh
--2016-01-11 03:50:00--  http://chrome.richardlloyd.org.uk/install_chrome.sh
Resolving chrome.richardlloyd.org.uk... 193.110.246.53
Connecting to chrome.richardlloyd.org.uk|193.110.246.53|:80... connected.
HTTP request sent, awaiting response... 200 OK
Length: 79768 (78K) [application/x-sh]
Saving to: “install_chrome.sh”

100%[================================================================================>] 79,768      --.-K/s   in 0.1s    

2016-01-11 03:50:01 (541 KB/s) - “install_chrome.sh” saved [79768/79768]

[root@localhost Downloads]# chmod +x install_chrome.sh 
[root@localhost Downloads]# ./install_chrome.sh 
</syntaxhighlight>

== Installation of Python 2.7 ==
* Next, you will need to install Python 2.7, since Red Hat default Python version is 2.6
* '''Warning:''' Red Hat OS depends on Python version 2.6, therefore, Python version 2.7 must coexist, and you are not allowed to replace version 2.6
* '''This should be done as root'''
<syntaxhighlight>
[root@localhost Downloads]# yum -y groupinstall "development tools"
[root@localhost Downloads]# yum -y install zlib-devel openssl openssl-devel
[root@localhost Downloads]# mkdir tmp
[root@localhost Downloads]# cd tmp
[root@localhost tmp]# wget http://python.org/ftp/python/2.7.3/Python-2.7.3.tgz
[root@localhost tmp]# tar zxvf Python-2.7.3.tgz
[root@localhost tmp]# cd Python-2.7.3
[root@localhost Python-2.7.3]# ./configure --prefix=/opt/python2.7 --enable-shared
[root@localhost Python-2.7.3]# make
[root@localhost Python-2.7.3]# make altinstall
[root@localhost Python-2.7.3]# echo "/opt/python2.7/lib" >> /etc/ld.so.conf.d/opt-python2.7.conf
[root@localhost Python-2.7.3]# ldconfig
</syntaxhighlight>

== Setup Path ==
* Go to your home directory, then edit your .bashrc file
* '''Note:''' You don’t have to be root to edit .bashrc, since this is your own account’s file
* Add this line to your .bashrc file:
<code>export PATH=${PATH}:/opt/python2.7/bin</code>
* For example:
<syntaxhighlight>
# .bashrc

# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi

# User specific aliases and functions
export PATH=${PATH}:/opt/python2.7/bin
</syntaxhighlight>
* Then source <code>.bashrc</code>
<syntaxhighlight>
[jon@localhost ~]$ source ./.bashrc
</syntaxhighlight>
* Confirm the Python 2.7 binary directory is now in your path:
<syntaxhighlight>
[jon@localhost ~]$ echo $PATH
/usr/lib64/qt-3.3/bin:/usr/local/bin:/bin:/usr/bin:/usr/local/sbin:/usr/sbin:/sbin:/home/jon/bin:/opt/python2.7/bin
</syntaxhighlight>

== Install PIP 2.7 ==
* '''Installation must be done as root'''
<syntaxhighlight>
[root@localhost ~]# cd /opt/python2.7/bin/
[root@localhost bin]# wget https://bootstrap.pypa.io/get-pip.py
[root@localhost bin]# ./python2.7 get-pip.py
Collecting pip
/tmp/tmpWViYfj/pip.zip/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  Downloading pip-7.1.2-py2.py3-none-any.whl (1.1MB)
    100% |████████████████████████████████| 1.1MB 306kB/s 
Collecting setuptools
  Downloading setuptools-19.2-py2.py3-none-any.whl (463kB)
    100% |████████████████████████████████| 466kB 719kB/s 
Collecting wheel
  Downloading wheel-0.26.0-py2.py3-none-any.whl (63kB)
    100% |████████████████████████████████| 65kB 4.5MB/s 
Installing collected packages: pip, setuptools, wheel
Successfully installed pip-7.1.2 setuptools-19.2 wheel-0.26.0
/tmp/tmpWViYfj/pip.zip/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
</syntaxhighlight>
* '''NB:''' If <code>wget</code> command does not work, use <code>wget --no-check-certificate</code> command

== Python 'requests' package ==
<syntaxhighlight>
[root@localhost bin]# ./pip2.7 install requests
Collecting requests
/opt/python2.7/lib/python2.7/site-packages/pip/_vendor/requests/packages/urllib3/util/ssl_.py:90: InsecurePlatformWarning: A true SSLContext object is not available. This prevents urllib3 from configuring SSL appropriately and may cause certain SSL connections to fail. For more information, see https://urllib3.readthedocs.org/en/latest/security.html#insecureplatformwarning.
  InsecurePlatformWarning
  Downloading requests-2.9.1-py2.py3-none-any.whl (501kB)
    100% |████████████████████████████████| 503kB 585kB/s 
Installing collected packages: requests
Successfully installed requests-2.9.1
</syntaxhighlight>

== Sample Script ==
=== Script code ===
* This is our example script
<syntaxhighlight>

import requests
import pprint
import time
import json
import sys

requests.packages.urllib3.disable_warnings()

if (len(sys.argv) != 2):
    print "\n **** ERROR **** Must pass IP address"
    print "     python2.7 redfish_sample_cmd.py ip_address"
    sys.exit(-1)

ip_address = sys.argv[1]

# Get authentication token.
# Note: 
#     user and password are default values: ADMIN, ADMIN
# Please modify them to match yours.
url = "https://%s/redfish/v1/SessionService/Sessions/" % (ip_address)
payload = {"UserName":"ADMIN","Password":"ADMIN"}
my_headers = {'content-type': 'application/json'}

response = requests.post(url, data=json.dumps(payload), headers=my_headers, verify=False)

# Get the response code, should be 201 
print "\n Response:\n %s" % response

# Next, get authorization token
Token = response.headers['x-auth-token ']
print "\n Authorization token: %s" % (Token)

# Use authorization token for the next command
# We use Chassis command as an example here
url = "https://%s/redfish/v1/Chassis/1" % (ip_address)
token_headers = {'X-Auth-Token': Token}

response1 = requests.get(url, headers=token_headers, verify=False).json()
print "\n Response:\n"
print (json.dumps(response1, indent=2))
</syntaxhighlight>

=== Run sample script ===
<syntaxhighlight>
[jon@localhost Desktop]$ python2.7 redfish_sample_cmd.py 10.0.0.181
</syntaxhighlight>
Sample output:
<syntaxhighlight>
 Response:
 <Response [201]>

 Authorization token: zzsh0qbs624u6pk4tj08ynh1glrmrl5t

 Response:

{
  "@odata.type": "#Chassis.1.0.0.Chassis", 
  "SKU": "", 
  "Name": "Computer System Chassis", 
  "PartNumber": "CSE-219UTS-R1K02P-T", 
  "AssetTag": "NONE", 
  "Links": {
    "ManagedBy": [
      {
        "@odata.id": "/redfish/v1/Managers/1"
      }
    ], 
    "ContainedBy": {
      "@odata.id": "/redfish/v1/Chassis/Rack1"
    }, 
    "ComputerSystems": [
      {
        "@odata.id": "/redfish/v1/Systems/1"
      }
    ]
  }, 
  "SerialNumber": "C219UAD50A20330", 
  "@odata.id": "/redfish/v1/Chassis/1", 
  "@odata.context": "/redfish/v1/$metadata#Chassis/Members/$entity", 
  "Status": {
    "State": "Enabled", 
    "Health": "OK"
  }, 
  "Thermal": {
    "@odata.id": "/redfish/v1/Chassis/1/Thermal"
  }, 
  "Power": {
    "@odata.id": "/redfish/v1/Chassis/1/Power"
  }, 
  "@Redfish.Copyright": "Copyright \u00a9 2014-2015 Distributed Management Task Force, Inc. (DMTF). All rights reserved.", 
  "IndicatorLED": "Off", 
  "Oem": {
    "OemFan": {
      "@odata.type": "#OemFan.Chassis", 
      "FanMode": "Optimal", 
      "FanMode@Redfish.AllowableValues": [
        "FullSpeed", 
        "Optimal", 
        "PUE2", 
        "HeavyIO"
      ]
    }
  }, 
  "ChassisType": "RackMount", 
  "Model": "NONE", 
  "Id": "1", 
  "Manufacturer": "Supermicro"
}
</syntaxhighlight>

== Fixing Python / SSL Warnings ==
* Certain Python platforms (specifically, versions of Python earlier than 2.7.9) have restrictions in their ssl module that limit the configuration that <code>urllib3</code> can apply. In particular, this can cause HTTPS requests that would succeed on more featureful platforms to fail, and can cause certain security features to be unavailable.
* Additionally, our example script performs unverified HTTPS requests, so you may see errors like the following:
<syntaxhighlight>
/opt/python2.7/lib/python2.7/site-packages/requests/packages/urllib3/connectionpool.py:791: InsecureRequestWarning: Unverified HTTPS request is being made. Adding certificate verification is strongly advised. See: https://urllib3.readthedocs.org/en/latest/security.html
  InsecureRequestWarning)
</syntaxhighlight>
* The general advice seems to be "upgrade to a more modern version of Python" which isn't always possible.
* If upgrading to a more modern version of Python is not an option, the warnings can be disabled.

=== Disabling Python / SSL Warnings ===
* According to [[https://urllib3.readthedocs.org/en/latest/security.html | https://urllib3.readthedocs.org/en/latest/security.html]], such warnings can be disabled by having the following in your Python code:
<syntaxhighlight>
import urllib3
urllib3.disable_warnings()
</syntaxhighlight>
* However, this won't work in our example script as it uses a separate instance of ''urllib3'', vendored inside of ''requests''. In which case, you'll want to try including the following in your main script (or from wherever ''requests'' is imported):
<syntaxhighlight>
import requests
requests.packages.urllib3.disable_warnings()
</syntaxhighlight>