Thursday, May 14, 2015

Listing Puppet Enterprise Groups in PE 3.7 with Python

some useful stackoverflow links:
#!/usr/bin/env python
import requests
import json
# curl https://${PEFQDN}:4433/classifier-api/v1/groups \
# -H "Content-Type: application/json" \
# --cert /etc/puppetlabs/puppet/ssl/certs/${PEFQDN}.pem \
# --key /etc/puppetlabs/puppet/ssl/private_keys/${PEFQDN}.pem \
# --cacert /etc/puppetlabs/puppet/ssl/certs/ca.pem | python -m json.tool
# if you get this error message:
#requests.exceptions.SSLError: [Errno 1] _ssl.c:504: error:14090086:SSL routines:SSL3_GET_SERVER_CERTIFICATE:certificate verify failed
# try executing: # pip install requests[security]
# to install pip execute:
# yum install python-pip
headers = {"Content-Type": "application/json"}data={}
result = requests.get(url,
        data=data, #no data needed for this request
        headers=headers, #dict {"Content-Type":"application/json"}
        cert=(cert,key), #key/cert pair         verify=cacert
print json.dumps( result.json(), sort_keys=True, indent=4, separators=(',', ': '))
for i in result.json():
        print i['name']
        print i['id']

Monday, May 04, 2015

good explanation of perl map


Using the Perl map() function


The map function is used for transforming lists element-wise: given a list and a code block, map builds a new list (or hash) with elements derived from the corresponding elements of the original.
The basic syntax is
    @out = map { CODE } @in;
where CODE is some perl code that is given an element of the list as $_ and returns the replacement value for the new list.

Example 1

Say you have a list of names, and you want to capitalise them all. We can use map along with the built-in function ucfirst to do them all at once:
    use strict;
    use warnings;

    my @names = qw(bob anne frank jill);
    my @capitalised_names = map { ucfirst $_ } @names;

    foreach my $name (@capitalised_names) {
        print "$name\n";
This produces the output:

Example 2: Multiple outputs per input

If your code block returns a list for each element, all the lists are concatenated into the result:
    use strict;
    use warnings;

 my @names = qw(bob anne frank jill);

    my @everyone = map {
        $_, $_ . "'s dog", $_ . "'s cat"
    } @names;

    foreach my $name (@everyone) {
        print "$name\n";
This produces the output:
    bob's dog
    bob's cat
    anne's dog
    anne's cat
    frank's dog
    frank's cat
    jill's dog
    jill's cat

Example 3: Producing a hash as output

Generating a hash is almost identical to earlier examples:
    use strict;
    use warnings;

    my @names = qw(bob anne frank jill);

    my %lengths = map { $_ => length $_ } @names;

    while (my ($name, $length) = each %lengths) {
        print "'$name' has $length characters\n";
This produces the output:
    'bob' has 3 characters
    'anne' has 4 characters
    'frank' has 5 characters
    'jill' has 4 characters

Example 4: Restructuring data

Say you have some data stored as a list of hashrefs and you want to convert it to a hash based on some key field id.
    use strict;
    use warnings;

    my @array = ({
        id      => 1,
        name    => 'Bob',
        id      => 2,
        name    => 'Anne',
        id      => 3,
        name    => 'Frank'

    my %hash = map { 
        $_->{id} => { name => $_->{name} } 
    } @array;

    for my $id (1..3) {
        my $name = $hash{$id}->{name};
        print "User $id: $name\n";
This produces the output:
    User 1: Bob
    User 2: Anne
    User 3: Frank

See also

    perldoc -f map

Friday, April 24, 2015

Generating files based on puppet array

First off a big thank you to alexharv074 and for giving me this solution.

I need to generate the files:

# more /tmp/rabbit-* /tmp/mongo-el7-001.cfg 
define host {
         use                     linux-server
         host_name               rabbit-1
         alias                   rabbit-1
         hostgroups              rabbit_hosts 
define host {
         use                     linux-server
         host_name               rabbit-2
         alias                   rabbit-2
         hostgroups              rabbit_hosts 
define host {
         use                     linux-server
         host_name               mongo-el7-001
         alias                   mongo-el7-001
         hostgroups              mongo_hosts 


... so I wrote this puppet class:

class make_files (
     $rabbit_servers = ['rabbit-1:','rabbit-2:'],
     $mongo_servers = ['mongo-el7-001:'],
) {
    define my_file ($content, $hostgroup) {
          $tuple = split($name, ':')
          $host_name = $tuple[0]
          $file_name = "/tmp/$host_name.cfg"
          $ipaddress = $tuple[1]
          $config = "define host {
              use                     linux-server
              host_name               $host_name
              alias                   $host_name
              hostgroups              $hostgroup 
              address                 $ipaddress

        file { $file_name:
          ensure  => file,
          content => $config,
    $rabbit_content = join($rabbit_servers, ',')
    my_file { $rabbit_servers: content => $rabbit_content, hostgroup => 'rabbit_hosts' }
    $mongo_content = join($mongo_servers, ',')
    my_file { $mongo_servers: content => $mongo_content, hostgroup => 'mongo_hosts' }

Tuesday, March 03, 2015

strace command

# strace -f -e trace=connect,read -s2048 glance --debug image-list > /tmp/st 2>&1

Wednesday, February 25, 2015

how to unblock hung unresponsive screen session

^a q

Thursday, January 22, 2015

disable selinux centos7


[root@localhost ~]# sestatus
SELinux status:                 enabled
SELinuxfs mount:                /sys/fs/selinux
SELinux root directory:         /etc/selinux
Loaded policy name:             targeted
Current mode:                   enforcing
Mode from config file:          enforcing
Policy MLS status:              enabled
Policy deny_unknown status:     allowed
Max kernel policy version:      28
now execute:

[root@localhost ~]# sed -i 's/enforcing/disabled/g' /etc/selinux/config 

then reboot