rss-motor v0.0.4 ~ a rubygem to ease up your RSS interactions

started a new rubygem project 'rss-motor' (http://rubygems.org/gems/rss-motor) to aid all RSS consuming code by providing the entire (or filtered as per choice) of feeds as Array of Hash values per Feed Item.

===============================================
 ||}}  //\  //\ _ ||\/|| ||@|| ~++~ ||@|| ||))
 ||\\ _\\  _\\    ||  || ||_||  ||  ||_|| ||\\
===============================================

I tried it in a new project 'rss-fanatic' (https://github.com/abhishekkr/rss-fanatic) making to help out RSS Feed fanatics collecting required content without pain of browsing/saving/downloading. Though RSS-Fanatic project is just started and shall be usable in some time soon.

Here is just a mini HowTo easily power you code with rss-motor:

First, obviously you'll need to install the gem

$  gem install rss-motor

or if luckily you already have a Gemfile usage, add following lines to it

source "http://rubygems.org"
gem 'rss-motor'


Now, currently available engines from the rss-motor

• simple way of getting all the items as array of key=value
  puts Rss::Motor.rss_items 'http://news.ycombinator.com/rss'

• get an array of items filtered by one or more keywords
  puts "#{Rss::Motor.rss_grep 'http://news.ycombinator.com/rss', ['ruby', 'android']}"

• to filter even the data of content available at >link/< field present in item plus normal filter
  puts "#{Rss::Motor.rss_grep_link 'http://news.ycombinator.com/rss', ['ruby', 'android']}"

now go on, ride your own rss-bikes.....

Get Set Go Lang ~ part#1

Get Set GO Lang

part# 1
_________________________

What Is Go Lang?
(in case you just came here while curious web surfing)


Go is an OpenSource programming platform developed by Google (and contributors) to be expressive and efficient at the same point.
It's distributed under BSD-style License
It's a concurrency favoring, statically typed, compiler-based language. Though it declares to be giving ease like dynamically typed interpreted code.
_________________________

On your mark, Get Set GO
(getting started with the quick boost usage)

To directly start playing with Go Lang, visit http://play.golang.org/,
where you can directly type/paste in your go-lang code in an online editor and run to get output.

Just a small ++HelluvaWorld code-piece

package main 

import ("fmt"
        "time"
        "os"
        "math" )

func main() {
  fmt.Println("Today is ", time.Now().Weekday())
  fmt.Println("env as ", os.Environ())

  fmt.Println("A Pi on Ceil looks like ",
               math.Ceil(math.Pi), 
      " and a Pie on Floor looks like", 
      math.Floor(math.Pi))
}

[] Installing it for local & full-flown development practice http://golang.org/doc/install would guide you getting 'go' working on your Linux, FreeBSD, OSX & Win platforms.
_________________________

Rewind before the Start Line and take your First Leap
(first useful step to starting use of Go Lang)

[] quickie at variables and constants, a look at GO's declaration style

// var used to declare variable with type at end
var a, b, c int
// direct initialization doesn't require providing type
var x, y, z = 1, true, "yes"
// constants just require a 'const' keyword
const newconst = 10
func tellvar() {
a, b, c = newconst + 1, newconst + 2, newconst + 3
// inside a function, even := construct
// could be used to assign and not use 'var'
clang, java, ruby := "dRitchie", "jGosling", "Matz"
fmt.Println(a, b, c, x, y, z, clang, ruby, java)
}

now, you also know '//' is to comment as in C/C++ and more.

[] mobilizing functions
just an emulation of 'math' libraries 'pow' method (also a look at using for loop)

package main 

import "fmt" 

func pow(x int, y int) int {
  a := 1
  for i := 0; i < y; i++ {
    a = a * x
  }
  return a
} 

func main() {
  fmt.Println( "2 to the power of 5 is ", pow(2, 5) )
}

[] some function parameters style, the pow above is same as

func pow(x, y int) int { ... }

[] function returning multiple values
dream come true of how a function can return any number of values (also use of if condition)

func plusminus(a, b int) (int, int) { 

     if a > b {return a+b, a-b} 

     return a+b, b-a

}

  or could be like

func plusminus(a, b int) (plus, minus int) { 

     plus = a + b 

    if a > b {   

                   minus = a - b  
     } else {    
       minus = b - a  
     }   
     return
   }

usage:

plus, minus := plusminus(1, 2)
fmt.Println("Plus: ", plus,
            "\nMinus: ", minus)

[] more to go..... in more to come


_________________________

Shops to Go
(other fine links to Go, until next part of this tutorial comes)

• Home Portal: http://golang.org/
• A Tour of Go: http://tour.golang.org/#1
• Google I/O 2010 Go Lang: @youtube
• Google I/O 2011 Writing WebApps in Go: @youtube
• Go Hangout with Brad & Andrew: @youtube
• Mailing List: http://groups.google.com/group/golang-nuts
• IRC Channel: irc://irc.freenode.net/#go-nuts
• Twitter: http://twitter.com/go_nuts
• Blog: http://blog.golang.org/
• Dashboard for Go Language: http://godashboard.appspot.com/project

_________________________

Puppet ~ a beginners concept guide (Part 1)

Someone asked me where to start with Puppet learning. I pointed them at PuppetLabs online doc for Puppet, which is actually nice for a proper understanding. 
But for someone trying to start with Puppet, that documentation is a bit long to read similar to any book. 
I searched for few blogs, but didn't found any content (short but enough, fundamentals but usable) that I was looking for.
____________________________________________________


Puppet
beginners concept guide (Part 1)

[] What  it  is?  When  is  it  required?  (for all new guys, who came here while just browsing internet)
Puppet is an OpenSource automated configuration management framework (which means a tool that knows how to configure all machines to a deterministic state once you provide it the required set of manifests pulling the correct strings).
It's managed at enterprise level by an organization called PuppetLabs (http://puppetlabs.com/).

It is required#1 when you have a hell-lot of machines required to be configured in a similar form.
It is required#2 when you have a infrastructure requirement of dynamic scale-up and scale-down of machines with a pre-determined (or at least metadata-calculated) configuration.
It is required#3 to have a control over all set of configured machines, so a centralized (master-server or repo-based) change gets propagated to all automatically.
And more scenarios come up as you require it.

_____________________________________


[] Quickie.
Install Ruby, Rubygems on your machine where you aim to test it.

$ gem install puppet --no-ri --no-rdoc

Download installers @Windows  @MacOSX ::&:: Docs to installing.

Checking, if it's installed properly and acting good

Now, 'puppet --version' shall give you the version of installed puppet once succeed.
Executing 'facter' and you shall get a list of System Environment related major information.

Have a quick puppet run, this shall create a directory '/tmp/pup' if absent. Creates a file '/tmp/pup/et' with 'look at me' as its content.
{In case of trying out on platforms without '/tmp' location. Like for Windows, change '/tmp' with 'C:/' or so}

$ puppet apply -e "file{'/tmp/pup':
                               ensure => 'directory'}
                             file{ '/tmp/pup/et':
                               ensure => 'present',
                               content => 'look at me',
                               require => File['/tmp/pup']}
                           "
_____________________________________


[] Dumb  usage  structure.
Create huge manifest for your node with all resources & data mentioned in it. Then directly apply that manifest file instead of '-e "abc{.....xyz}"'.

Say if the example above is your entire huge configuration commandment for the node. Copy all that to a file say 'mynode.pp'.
Then apply it similarly like
$ puppet apply mynode.pp

_____________________________________


[] How  it  evolves?

Now, as any application had pluggable library components to be loaded and shared as and when required. Puppet too have a concept of modules. These modules can have manifests, files-serving and more.

Modules can be created in any design preference. Normally it works by having different modules per system component. To entertain different logical configuration states for any given system component (and also keeping it clean) further re-factoring can be done in the modules' manifest dividing it into different scopes.

Taking example of a module for 'apache httpd'. For a very basic library, you might wanna structure your module like

• a directory base for your module:  <MODULE_PATH>httpd/
• a directory in module to serve static files:   <MODULE_PATH>/httpd/files
• static configuration file for httpd:   <MODULE_PATH>/httpd/files/myhttpd.conf
  AccessFileName .acl
• directory to hold your manifests in module:   <MODULE_PATH>/httpd/manifests/
• a complete solution manifest:   <MODULE_PATH>/httpd/manifests/init.pp
  class httpd{
    include httpd::install
    include httpd::config
    include httpd::service
  }
• a manifest just installing httpd:    <MODULE_PATH>/httpd/manifests/install.pp
  class httpd::install {  package {'httpd': ensure => 'installed'}
  }
• a manifest just configuring httpd:    <MODULE_PATH>/httpd/manifests/config.pp
  class httpd::config{  file {'/etc/httpd/conf.d/httpd.conf':
      ensure => 'present',
      source => 'puppet:///modules/httpd/myhttpd.conf'
    }
  }
• a manifest just handling httpd service:  <MODULE_PATH>/httpd/manifests/service.pp
  class httpd::service{
    service{'httpd': ensure => 'running' }
  }

Now, using it

  $ puppet apply --modulepath=<MODULE_PATH>  -e "include httpd"
would install, custom-configure and start the httpd service.


  $ puppet apply --modulepath=<MODULE_PATH>  -e "include httpd::install"
would just install the httpd service.



________________________________________________________________

Part2: Road to Modules

xml-motor ~ what it is; how & why should you use it

xml-motor ~ what it is; why & how you should use it

Download this article as pdf on what,why,how
http://speakerdeck.com/u/abhishekkr/p/xml-motor-whatwhyhow-this-xml-parsing-rubygem#


or read it all here.....

Late 2011, I started with a new rubygem project for parsing xml, html content.
  @Rubygems: http://rubygems.org/gems/xml-motor
  @GitHub     : https://github.com/abhishekkr/rubygem_xml_motor

Just created it to test out my work at compact, quick & easy xml-parsing algorithm... can see that
  @Slideshare: http://www.slideshare.net/AbhishekKr/xmlmotor

So, currently this is a non-native, completely independent less-than-250 ruby-LOC available as a simple rubygem to be require-d and use in an easy freehand notation and match with any node attributes.

Current Features:

• Has a single method access to parse require xml nodes from content or file. Use it only if you are gonna parse that xml-content once. For using same xml-content more than once, follow the 3-way step mentioned in examples.
• It doesn't depend on presence of any other system library, purely non-native.
• It parses broken or corrupted xml/html content correctly, just for the content it have.
• Can parse results on looking for node-names, attributes of node or both.
• Uses free-freehand notation to retrieve desired xml nodes
  if your xml looks like,
  '<library>...
    <book> <title>ABC</title> <author>CBA</author> </book>...
    <book>
      <title>XYZ</title>
       <authors> <author>XY</author><author>YZ</author> </authors></book>...
  </library>'
  and you look for 'book.author',
  then, you'll get back ['CBA', 'XY', 'YZ'];
  what that means is the child-node could be at any depth in the parent-node.
• Default return mode is without the tags, there is a switch to get the nodes.
  as you'd have seen in above example:
  'CBA' gets sent by default, not 'CBA'
• To filter your nodes on the basis of attributes, single or multiple attributes can be provided.
• These attribute searches can be combined up with freehand node name searches.
• Readme (a bit weird): https://raw.github.com/abhishekkr/rubygem_xml_motor/master/README

Features To Come:

• Work on making it more performance efficient.
• Limit over result-nodes retrieved from start/end of matching nodes.
• Multi-node attribute-based filter for a hierarchical node search.
• Add dev-knows CSS Selector, it's already present using attribute based search... just need to add a mapping method.

EXAMPLES of usage:
example code to try: https://github.com/abhishekkr/axml-motor/tree/master/ruby/examples

• say, you have an xml file 'dummy.xml', with data as
  <dummy>
    <ummy>    <mmy class="sys">non-native</mmy>  </ummy>
    <ummy>
      <mmy class="sys">      <my class="sys" id="mem">compact</my>    </mmy>
    </ummy>
    <mmy type="user">    <my class="usage">easy</my>  </mmy></dummy>
• its available at rubygems.org, install it as
    $ gem install xml-motor
• include it in your ruby code,
    #!/usr/bin/env ruby
    require 'xml-motor'
• get the XML Filename and/or XML data available
    fyl = File.join(File.expand_path(File.dirname __FILE__),'dummy.xml')
    xml = File.open(fyl,'r'){|fr| fr.read }
• One-time XML-Parsing directly from file
    XMLMotor.get_node_from_file(fyl, 'ummy.mmy', 'class="sys"')
       Result: ["non-native", "\n      compact\n    "]
• One-time XML-Parsing directly from content
    XMLMotor.get_node_from_content xml, 'dummy.my', 'class="usage"'
       Result: ["easy"]
    
• Way to go for XML-Parsing for xml node searches
    xsplit = XMLMotor.splitter xml
    xtags  = XMLMotor.indexify xsplit
  
    [] just normal node name based freehand notation to search:
      XMLMotor.xmldata xsplit, xtags, 'dummy.my'
      Result: ["compact", "easy"]
    [] searching for values of required nodes filtered by attribute:
      XMLMotor.xmldata xsplit, xtags, nil, 'class="usage"'
      Result: ["easy"]
  
    [] searching for values of required nodes filtered by freehand tag-name notation & attribute:
      XMLMotor.xmldata xsplit, xtags, 'dummy.my', 'class="usage"'
      Result: ["easy"]
  
    [] searching for values of required nodes filtered by freehand tag-name notation & multiple attributes:
      XMLMotor.xmldata xsplit, xtags, 'dummy.my', ['class="sys"', 'id="mem"']
      Result: ["compact"]

messQ ~ just a fun little project providing socket-based Queue service

messQ is a small project started to implement and improve in the areas of message queue mechanisms.

What it does currently? Just a Network Service to be connect and enqueue/dequeue messages.

What it requires? Ruby, terminal and your fingers :)

Git it:           $ git clone git://github.com/abhishekkr/messQ.git
Download:   https://github.com/abhishekkr/messQ/tarball/master

Start messQ server:       $ ruby messQ.rb
  This starts a message queue server at  port 8888.

Enque new message:
  Open a connection at port 8888, then say "enq MESSAGE_TO_BE_QUEUED".

Deque oldest message:
  Open a connection at port 8888, then say "deq". It returns the dequed message.

+++++++++++++++++++++++++++++++++++++++++++++++++++++++
+++++++++++++++++++++++++++++++++++++++++++++++++++++++
 _  _   __   ___  ___     _____
||\/|| //_  //_  //_  _  //  //  messQ v0.0.1beta
||  || \\_  __// __//   //__//\\_  simplistic socket message Q

+++++++++++++++++++++++++++++++++++++++++++++++++++++++

Basics of Powershell ~ empowering Windows Config/Admin Automation

Basics  of  MS Windows Powershell

Introduction
A dotNet framework based scripting language to automate the configuration/administration of Microsoft Windows machine.
Powershell is loaded with several cmdlets (special command-lets) acting as a built-in shell utilities to perform different tasks on Windows machine for performing administrative tasks.


Getting Started
Powershell's cmdlets act upon and return objects as a result of any action taken.
These can be used in combination with traditional Windows services like Registry, Net and more.

To try your hands over powershell, access it at 'Start Menu' > 'Accessories' > 'Windows Powershell';
there you'll get mainly a shell from 'Powershell', and an interactive IDE-like shell 'Powershell ISE'.

Using powershell, cmdlets are the main power-source of this Powershell which are discussed briefly below.....

to get a quick /Hello World/ feel of Powershell, you could try on few next steps
* emulating a dos command 'echo' used to print message at console, 
   command: 
      Write-Host "[get-help write-host] would tell about cmdlet write-host"
* emulating a dos command 'cd' used to change current directory, 
   command: Set-Location C:\Temp
* emulating a dos command 'mkdir' used to create directory, 
   command: New-Item -name "ztemp" -type directory -Force

* emulating a dos command 'dir' used to list items in current directory, 
   command: Get-ChildItem -path C:\Temp

* even the windows 'dir' command can be executed and played with inside powershell.
.....could get a list of cmdlets available in Powershell2.0 ~ http://ss64.com/ps/

[] cmdlets

Command-lets have a specific name format of /'verb'-'noun'/ such as 'Get-ChildItem', 'Get-Help', etc.
To know more about any 'cmdlet' (like using man in linux shell), use
command: Get-Help <_cmdlet_> -detailed

[] A Glimpse of system level SuperUser stuff, as possible on a linux shell
  [+] to get a listing of all System Services,
          command:  Get-Service
  [+] to just get a listing of 'Spooler' named system service, telling its 'name','status' and 'display name'
          command:  Get-Service | Where {$_.name -eq 'Spooler'}
  [+] to get current state of 'Spooler' named system service, whether its running/stopped/paused
          command:  Get-Service | Where {$_.name -eq 'Spooler'} | %{ $_.status }
  [+] to have a Powershell script, check for a system service..... start it if stopped

  $svc_name = "aspnet_state"
  $svc_status = Get-Service | Where {$_.name -eq $svc_name} | %{ $_.status }
  if (-not $svc_status) {
     Write-Host "Error: $svc_name not found"
  }
  elseif ($svc_status -eq "running"){
     Write-Host "status ok $svc_name"
  } else {
     Start-Service $svc_name
  }

  [+] Now you can save the script above as any file say 'start_aspnet.ps1', but to execute it as an external script you would need the local system's Execution Policies to be unrestricted for the script.
       It's not advisable to have it un-restricted all the times, so you could pass on the specific modes along-with the script you desire to be run in un-restricted mode. As below.....
          cmd_prompt:> powershell -executionpolicy unrestricted -file ".\start_aspnet.ps1"
     


helpful links:
http://msdn.microsoft.com/en-us/library/windows/desktop/aa973757(v=vs.85).aspx
http://blogs.msdn.com/b/powershell/
http://thepowershellguy.com/blogs/posh/default.aspx
http://powershell.com/cs/
http://stackoverflow.com/questions/496234/what-tutorial-do-you-recommend-for-learning-powershell

XML-Motor v0.0.3 ~ mine XML once..... multiple search

released v0.0.3 of xml-motor with following update: http://rubygems.org/gems/xml-motor

Earlier:
  * it just supported one search per every XML data processing
Now:
  * could retrieve processed XML 'Information' once, and search again & again with minimized cost

Now, along-with.....
  * a single method-call search for Tag (w/ or w/o Attribute) in provided XML String or File
You also have the capability to.....
  * fetch the two (or one, depends how you wanna roll) required set of Information mined by providing it XML String
  * then provide that information everytime to search anything, and hence making it way quicker for multiple searches

So, the improved way for multiple searches:

  First, update your 'xml-motor' gem using
    $ gem install xml-motor

  Now, the way to use it

#!/usr/bin/env ruby
require 'xml-motor'

fyl = File.open "myXMLfile.xml"
str = fyl.read
xNodes = XMLMotorEngine._splitter_ str
xTags = XMLMotorEngine._indexify_ xNodes
result1 = XMLMotorEngine.pre_processed_content(
            xNodes, xTags, "h1")
result2 = XMLMotorEngine.pre_processed_content(
            xNodes, xTags, "div", "class='wanted'")