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Apr
03
2018
How to run Ansible2.5 on CentOS 5

[notes based on a docker centos5]

# cat /etc/redhat-release

CentOS release 5.11 (Final)

Setup Enviroment

Install compiler:

# yum -y install gcc make

Install zlib headers:

# yum -y install zlib-devel

Install tools:

# yum -y install curl unzip

SSL/TLS Errors

If you are on a CentOS 5x machine, when trying to download files from the internet, you will get this error msg:

This is a brown out of TLSv1 support. TLSv1 support is going away soon, upgrade to a TLSv1.2+ capable client.

or

SSL routines:SSL23_GET_SERVER_HELLO:tlsv1 alert protocol version

that is because CentOS 5x has an old cipher suite that doesnt work with today’s standards.

OpenSSL

To bypass these SSL/TLS errors, we need to install a recent version of openssl.

# cd /root/

# curl -LO https://www.openssl.org/source/openssl-1.0.2o.tar.gz
# tar xf openssl*.tar.gz
# cd openssl*

# ./Configure shared linux-x86_64
# make
# make install

The output has a useful info:

OpenSSL shared libraries have been installed in:
  /usr/local/ssl

So, we have to update the system’s library paths, to include this one:

# echo "/usr/local/ssl/lib/" >> /etc/ld.so.conf
# /sbin/ldconfig

Python 2.7

Download the latest Python2.7

# cd /root/
# curl -LO https://www.python.org/ftp/python/2.7.14/Python-2.7.14.tgz
# tar xf Python*.tgz
# cd Python*

Install Python:

# ./configure --prefix=/opt/Python27 --enable-shared
# make
# make install

PATH

# export PATH=/opt/Python27/bin/:$PATH

# python -c "import ssl; print(ssl.OPENSSL_VERSION)"
OpenSSL 1.0.2o  27 Mar 2018

SetupTools

Download the latest setuptools

# cd /root/

# export PYTHONHTTPSVERIFY=0
# python -c 'import urllib; urllib.urlretrieve ("https://pypi.python.org/packages/72/c2/c09362ab29338413ab687b47dab03bab4a792e2bbb727a1eb5e0a88e3b86/setuptools-39.0.1.zip", "setuptools-39.0.1.zip")'

Install setuptools

# unzip setuptools*.zip
# cd setuptools*

# python2.7 setup.py build
# python2.7 setup.py install

PIP

Install PIP

# cd /root/

# easy_install pip

Searching for pip
Reading https://pypi.python.org/simple/pip/
Downloading https://pypi.python.org/packages/4b/5a/8544ae02a5bd28464e03af045e8aabde20a7b02db1911a9159328e1eb25a/pip-10.0.0b1-py2.py3-none-any.whl#md5=34dd54590477e79bc681d9ff96b9fd39
Best match: pip 10.0.0b1
Processing pip-10.0.0b1-py2.py3-none-any.whl
Installing pip-10.0.0b1-py2.py3-none-any.whl to /opt/Python27/lib/python2.7/site-packages
writing requirements to /opt/Python27/lib/python2.7/site-packages/pip-10.0.0b1-py2.7.egg/EGG-INFO/requires.txt
Adding pip 10.0.0b1 to easy-install.pth file
Installing pip script to /opt/Python27/bin
Installing pip3.6 script to /opt/Python27/bin
Installing pip3 script to /opt/Python27/bin

Installed /opt/Python27/lib/python2.7/site-packages/pip-10.0.0b1-py2.7.egg
Processing dependencies for pip
Finished processing dependencies for pip

Ansible

Now, we are ready to install ansible

# pip install ansible

Collecting ansible

/opt/Python27/lib/python2.7/site-packages/pip-10.0.0b1-py2.7.egg/pip/_vendor/urllib3/util/ssl_.py:339: SNIMissingWarning: An HTTPS request has been made, but the SNI (Subject Name Indication) extension to TLS is not available on this platform. This may cause the server to present an incorrect TLS certificate, which can cause validation failures. You can upgrade to a newer version of Python to solve this. For more information, see https://urllib3.readthedocs.io/en/latest/advanced-usage.html#ssl-warnings
  SNIMissingWarning
  Using cached ansible-2.5.0-py2.py3-none-any.whl
Collecting paramiko (from ansible)
  Using cached paramiko-2.4.1-py2.py3-none-any.whl
Collecting cryptography (from ansible)
  Using cached cryptography-2.2.2-cp27-cp27m-manylinux1_x86_64.whl
Requirement already satisfied: setuptools in /opt/Python27/lib/python2.7/site-packages/setuptools-39.0.1-py2.7.egg (from ansible) (39.0.1)
Collecting PyYAML (from ansible)
  Using cached PyYAML-3.12.tar.gz
Collecting jinja2 (from ansible)
  Using cached Jinja2-2.10-py2.py3-none-any.whl
Collecting pyasn1>=0.1.7 (from paramiko->ansible)
  Using cached pyasn1-0.4.2-py2.py3-none-any.whl
Collecting bcrypt>=3.1.3 (from paramiko->ansible)
  Using cached bcrypt-3.1.4-cp27-cp27m-manylinux1_x86_64.whl
Collecting pynacl>=1.0.1 (from paramiko->ansible)
  Using cached PyNaCl-1.2.1-cp27-cp27m-manylinux1_x86_64.whl
Collecting six>=1.4.1 (from cryptography->ansible)
  Using cached six-1.11.0-py2.py3-none-any.whl
Collecting cffi>=1.7; platform_python_implementation != "PyPy" (from cryptography->ansible)
  Using cached cffi-1.11.5-cp27-cp27m-manylinux1_x86_64.whl
Collecting enum34; python_version < "3" (from cryptography->ansible)
  Using cached enum34-1.1.6-py2-none-any.whl
Collecting asn1crypto>=0.21.0 (from cryptography->ansible)
  Using cached asn1crypto-0.24.0-py2.py3-none-any.whl
Collecting idna>=2.1 (from cryptography->ansible)
  Using cached idna-2.6-py2.py3-none-any.whl
Collecting ipaddress; python_version < "3" (from cryptography->ansible)
  Using cached ipaddress-1.0.19.tar.gz
Collecting MarkupSafe>=0.23 (from jinja2->ansible)
  Using cached MarkupSafe-1.0.tar.gz
Collecting pycparser (from cffi>=1.7; platform_python_implementation != "PyPy"->cryptography->ansible)
  Using cached pycparser-2.18.tar.gz
Installing collected packages: pyasn1, six, pycparser, cffi, bcrypt, enum34, asn1crypto, idna, ipaddress, cryptography, pynacl, paramiko, PyYAML, MarkupSafe, jinja2, ansible
  Running setup.py install for pycparser ... done
  Running setup.py install for ipaddress ... done
  Running setup.py install for PyYAML ... done
  Running setup.py install for MarkupSafe ... done

Successfully installed MarkupSafe-1.0 PyYAML-3.12 ansible-2.5.0 asn1crypto-0.24.0 bcrypt-3.1.4 cffi-1.11.5 cryptography-2.2.2 enum34-1.1.6 idna-2.6 ipaddress-1.0.19 jinja2-2.10 paramiko-2.4.1 pyasn1-0.4.2 pycparser-2.18 pynacl-1.2.1 six-1.11.0

Version

# ansible --version

ansible 2.5.0
  config file = None
  configured module search path = [u'/root/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /opt/Python27/lib/python2.7/site-packages/ansible
  executable location = /opt/Python27/bin/ansible
  python version = 2.7.14 (default, Mar 31 2018, 20:00:21) [GCC 4.1.2 20080704 (Red Hat 4.1.2-55)]

Ansible v2

# ansible -m ping localhost


localhost | SUCCESS => {
    "changed": false,
    "ping": "pong"
}

Ansible v1

or a previous version for testing

eg. 1.9.6

# pip install 'ansible==1.9.6'

# ansible --version

ansible 1.9.6
  configured module search path = None

# yum -y install python-simplejson

# ansible localhost -c local -m ping -i "localhost,"

localhost | success >> {
    "changed": false,
    "ping": "pong"
}

Possible Building Error

When building python from source, setup.py will try to look for /usr/local/ssl/ directory to find the libraries and included headers of openssl. Althouth it works from _ssl.c , it doesnt for _hashlib.c.

To fix this problem, you must manual edit the Python-2.7.14/setup.py

 869                 ssl_incs += ['/usr/local/ssl/include']
 870                 ssl_libs += ['/usr/local/ssl/lib']

the full code is:

 865         if have_any_openssl:
 866             if have_usable_openssl:
 867                 # The _hashlib module wraps optimized implementations
 868                 # of hash functions from the OpenSSL library.
 869                 ssl_incs += ['/usr/local/ssl/include']
 870                 ssl_libs += ['/usr/local/ssl/lib']
 871                 exts.append( Extension('_hashlib', ['_hashopenssl.c'],
 872                                        include_dirs = ssl_incs,
 873                                        library_dirs = ssl_libs,
 874                                        libraries = ['ssl', 'crypto']) )
 875             else:
 876                 print ("warning: openssl 0x%08x is too old for _hashlib" %
 877                        openssl_ver)
 878                 missing.append('_hashlib')

hope that helps!

Mar
31
2018
Working with Yaml and Jinja2 in Python3

YAML

YAML is a human friendly data serialization standard, especially for configuration files. Its simple to read and use.

Here is an example:

---
# A list of tasty fruits
fruits:
    - Apple
    - Orange
    - Strawberry
    - Mango

btw the latest version of yaml is: v1.2.

PyYAML

Working with yaml files in python is really easy. The python module: PyYAML must be installed in the system.

In an archlinux box, the system-wide installation of this python package, can be done by typing:

$ sudo pacman -S --noconfirm python-yaml

Python3 - Yaml Example

Save the above yaml example to a file, eg. fruits.yml
Open the Python3 Interpreter and write:

$ python3.6
Python 3.6.4 (default, Jan  5 2018, 02:35:40)
[GCC 7.2.1 20171224] on linux
Type "help", "copyright", "credits" or "license" for more information.
>>> from yaml import load 

>>> print(load(open("fruits.yml")))
{'fruits': ['Apple', 'Orange', 'Strawberry', 'Mango']}
>>>

an alternative way is to write the above commands to a python file:

from yaml import load
print(load(open("fruits.yml")))

and run it from the console:

$ python3 test.py
{'fruits': ['Apple', 'Orange', 'Strawberry', 'Mango']}

Instead of print we can use yaml dump:

eg.

import yaml

yaml.dump(yaml.load(open("fruits.yml")))
'fruits: [Apple, Orange, Strawberry, Mango]n'

The return type of yaml.load is a python dictionary:

type(load(open("fruits.yml")))
<class 'dict'>

Have that in mind.

Jinja2

Jinja2 is a modern and designer-friendly templating language for Python.

As a template engine, we can use jinja2 to build complex markup (or even text) output, really fast and efficient.

Here is an jinja2 template example:

I like these tasty fruits:
* {{ fruit }}

where {{ fruit }} is a variable.
Declaring the fruit variable with some value and the jinja2 template can generate the prefarable output.

python-jinja

In an archlinux box, the system-wide installation of this python package, can be done by typing:

$ sudo pacman -S --noconfirm python-jinja

Python3 - Jinja2 Example

Below is a python3 - jinja2 example:

import jinja2

template = jinja2.Template("""
I like these tasty fruits:
* {{ fruit }}
""")

data = "Apple"
print(template.render(fruit=data))

The output of this example is:

I like these tasty fruits:
* Apple

File Template

Reading the jinja2 template from a template file, is a little more complicated than before. Building the jinja2 enviroment is step one:

env = jinja2.Environment(loader=jinja2.FileSystemLoader("./"))

and Jinja2 is ready to read the template file:

template = env.get_template("t.j2")

The template file: t.j2 is a litle diferrent than before:

I like these tasty fruits:
{% for fruit in fruits -%}
* {{ fruit }}
{% endfor %}

Yaml, Jinja2 and Python3

To render the template a dict of global variables must be passed. And parsing the yaml file the yaml.load returns a dictionary! So everything are in place.

Compine everything together:

from yaml import load
from jinja2 import Environment, FileSystemLoader

mydata = (load(open("fruits.yml")))

env = Environment(loader=FileSystemLoader("./"))
template = env.get_template("t.j2")

print(template.render(mydata))

and the result is:

$ python3 test.py

I like these tasty fruits:
* Apple
* Orange
* Strawberry
* Mango
Jan
21
2018
Fabric MiniTutorial

Fabric

Fabric is a Python (2.5-2.7) library and command-line tool for streamlining the use of SSH for application deployment or systems administration tasks.

You can find the documentation here

Installation

# yum -y install epel-release

# yum -y install fabric

Hello World

# cat > fabfile.py <<EOF
> def hello():
>     print("Hello world!")
>
> EOF

and run it

# fab hello -f ./fabfile.py

Hello world!

Done.

A more complicated example

def HelloWorld():
        print("Hello world!")

def hello(name="world"):
        print("Hello %s!" % name )
# fab HelloWorld -f ./fabfile.py
Hello world!

Done.

# fab hello -f ./fabfile.py
Hello world!

Done.

# fab hello:name=ebal -f ./fabfile.py
Hello ebal!

Done.

A remote example


from fabric.api import run , env

env.use_ssh_config = True

def HelloWorld():
    print("Hello world!")

def hello(name="world"):
    print("Hello %s!" % name )

def uptime():
    run('uptime')

ssh configuration file

with the below variable declaration
(just remember to import env)
fabric can use the ssh configuration file of your system

  env.use_ssh_config = True

and run it against server test

$ fab -H test uptime -f ./fabfile.py

[test] Executing task 'uptime'
[test] run: uptime
[test] out:  20:21:30 up 10 days, 11 min,  1 user,  load average: 0.00, 0.00, 0.00
[test] out: 

Done.
Disconnecting from 192.168.122.1:22... done.
Tag(s): python, fabric
Aug
04
2016
Open compressed file with gzip zcat perl php lua python

I have a compressed file of:


250.000.000 lines
Compressed the file size is: 671M
Uncompressed, it's: 6,5G

Need to extract a plethora of things and verify some others.

I dont want to use bash but something more elegant, like python or lua.

Looking through “The-Internet”, I’ve created some examples for the single purpose of educating my self.

So here are my results.
BE AWARE they are far-far-far away from perfect in code or execution.

Sorted by (less) time of execution:

pigz

pigz - Parallel gzip - Zlib



# time pigz  -p4 -cd  2016-08-04-06.ldif.gz &> /dev/null 

real    0m9.980s
user    0m16.570s
sys 0m0.980s

gzip

gzip 1.8



# time /bin/gzip -cd 2016-08-04-06.ldif.gz &> /dev/null

real    0m23.951s
user    0m23.790s
sys 0m0.150s

zcat

zcat (gzip) 1.8



# time zcat 2016-08-04-06.ldif.gz &> /dev/null

real    0m24.202s
user    0m24.100s
sys 0m0.090s

Perl

Perl v5.24.0

code:



#!/usr/bin/perl

open (FILE, '/bin/gzip -cd 2016-08-04-06.ldif.gz |');

while (my $line = ) {
  print $line;
}

close FILE;

time:


# time ./dump.pl &> /dev/null

real    0m49.942s
user    1m14.260s
sys 0m2.350s

PHP

PHP 7.0.9 (cli)

code:


#!/usr/bin/php

< ? php

  $fp = gzopen("2016-08-04-06.ldif.gz", "r");

  while (($buffer = fgets($fp, 4096)) !== false) {
        echo $buffer;
  }

  gzclose($fp);

 ? >

time:


# time php -f dump.php &> /dev/null

real    1m19.407s
user    1m4.840s
sys 0m14.340s

PHP - Iteration #2

PHP 7.0.9 (cli)

Impressed with php results, I took the perl-approach on code:



< ? php

  $fp = popen("/bin/gzip -cd 2016-08-04-06.ldif.gz", "r");

  while (($buffer = fgets($fp, 4096)) !== false) {
        echo $buffer;
  }

  pclose($fp);

 ? >

time:


# time php -f dump2.php &> /dev/null 

real    1m6.845s
user    1m15.590s
sys 0m19.940s

not bad !

Lua

Lua 5.3.3

code:


#!/usr/bin/lua

local gzip = require 'gzip'

local filename = "2016-08-04-06.ldif.gz"

for l in gzip.lines(filename) do
  print(l)
end

time:


# time ./dump.lua &> /dev/null

real    3m50.899s
user    3m35.080s
sys 0m15.780s

Lua - Iteration #2

Lua 5.3.3

I was depressed to see that php is faster than lua!!
Depressed I say !

So here is my next iteration on lua:

code:


#!/usr/bin/lua

local file = assert(io.popen('/bin/gzip -cd 2016-08-04-06.ldif.gz', 'r'))

while true do
        line = file:read()
        if line == nil then break end
        print (line)
end
file:close()

time:


# time ./dump2.lua &> /dev/null 

real    2m45.908s
user    2m54.470s
sys 0m21.360s

One minute faster than before, but still too slow !!

Lua - Zlib

Lua 5.3.3

My next iteration with lua is using zlib :

code:



#!/usr/bin/lua

local zlib = require 'zlib'
local filename = "2016-08-04-06.ldif.gz"

local block = 64
local d = zlib.inflate()

local file = assert(io.open(filename, "rb"))
while true do
  bytes = file:read(block)
  if not bytes then break end
  print (d(bytes))
end

file:close()

time:



# time ./dump.lua  &> /dev/null 

real    0m41.546s
user    0m40.460s
sys 0m1.080s

Now, that's what I am talking about !!!

Playing with window_size (block) can make your code faster or slower.

Python v3

Python 3.5.2

code:


#!/usr/bin/python

import gzip

filename='2016-08-04-06.ldif.gz'
with gzip.open(filename, 'r') as f:
    for line in f:
        print(line,)

time:


# time ./dump.py &> /dev/null

real    13m14.460s
user    13m13.440s
sys 0m0.670s

Not enough tissues on the whole damn world!

Python v3 - Iteration #2

Python 3.5.2

but wait ... a moment ... The default mode for gzip.open is 'rb'.
(read binary)

let's try this once more with rt(read-text) mode:

code:


#!/usr/bin/python

import gzip

filename='2016-08-04-06.ldif.gz'
with gzip.open(filename, 'rt') as f:
    for line in f:
        print(line, end="")

time:


# time ./dump.py &> /dev/null 

real    5m33.098s
user    5m32.610s
sys 0m0.410s

With only one super tiny change and run time in half!!!
But still tooo slow.

Python v3 - Iteration #3

Python 3.5.2

Let's try a third iteration with popen this time.

code:


#!/usr/bin/python

import os

cmd = "/bin/gzip -cd 2016-08-04-06.ldif.gz"
f = os.popen(cmd)
for line in f:
  print(line, end="")
f.close()

time:


# time ./dump2.py &> /dev/null 

real    6m45.646s
user    7m13.280s
sys 0m6.470s

Python v3 - zlib Iteration #1

Python 3.5.2

Let's try a zlib iteration this time.

code:



#!/usr/bin/python

import zlib

d = zlib.decompressobj(zlib.MAX_WBITS | 16)
filename='2016-08-04-06.ldif.gz'

with open(filename, 'rb') as f:
    for line in f:
        print(d.decompress(line))

time:


# time ./dump.zlib.py &> /dev/null 

real    1m4.389s
user    1m3.440s
sys 0m0.410s

finally some proper values with python !!!

Specs

All the running tests occurred to this machine:


4 x Intel(R) Core(TM) i3-3220 CPU @ 3.30GHz
8G RAM

Conclusions

Ok, I Know !

The shell-pipe approach of using gzip for opening the compressed file, is not fair to all the above code snippets.
But ... who cares ?

I need something that run fast as hell and does smart things on those data.

Get in touch

As I am not a developer, I know that you people know how to do these things even better!

So I would love to hear any suggestions or even criticism on the above examples.

I will update/report everything that will pass the "I think I know what this code do" rule and ... be gently with me ;)

PLZ use my email address: evaggelos [ _at_ ] balaskas [ _dot_ ] gr

to send me any suggestions

Thanks !

Tag(s): php, perl, python, lua, pigz
Aug
23
2013
python argentina’s magazines

Do yourself a favor and read the below three docs (doesnt matter if you are not a python developer)

Plz read them

Tag(s): python