Schleichermann's Weblog

CentOS: Installing Git

schleichermann — Thu, 08 Dec 2011 20:02:41 +0000

You might notice that many Virtual Private Servers (VPS) are running the CentOS linux distribution. In its standard source repositories it does not have Git which we Ruby developers tend to use as our source code repositories. Due to this when you run the command ‘yum install git’ you get a message back stating it does not exist.

If you have googled for a solution you will run into a ton of really complicated solutions which require in-depth linux package management knowledge. For those of us who really aren’t interested in becoming linux server administrators its way too complicated and takes too long to figure out. That being said I like to take the easy route and I found this through all my searching and it worked on my CentOS VPS on Hostingrails.

rpm -Uvh http://download.fedora.redhat.com/pub/epel/5/i386/epel-release-5-4.noarch.rpm
yum install git

Rails 3: Polymorphic liking of Entities by User, how?

schleichermann — Fri, 22 Jul 2011 07:10:50 +0000

Just in case you are trying to implement Facebook style ‘Liking’ to your Rails application from scratch here is how I did it as well as how other StackOverflow users would tackle the issues as well using a Polymorphic Data Model in Rails 3

http://stackoverflow.com/questions/6778269/rails-3-polymorphic-liking-of-entities-by-user-how/6786530#6786530

Alarmist? Sales Pitch? Maybe, but it sure makes you think!

schleichermann — Thu, 09 Jun 2011 04:30:35 +0000

Alarmist? Sales Pitch? Maybe, but it sure makes you think!

What are we in for? How will this all play out?

http://www.stansberryresearch.com/pro/1103PSIEOAVD/LPSIM639/PR

Rails: Flash Message Partial (self-hiding)

schleichermann — Thu, 09 Jun 2011 02:09:39 +0000

(Wed. June 8th 2o11, 11:00 pm)

For self -hiding Ruby on Rails 3 flash messages you can use the following in a partial which can be included within application layouts. (requires you are using jQuery)


<% flash.each do |key, msg| %>
<%= content_tag :div, msg, :class => "flash " + key.to_s, :id => key.to_s + "-message" %>
<% content_tag :script, :type => "text/javascript" do %>
$('#<%= key.to_s + "-message" %>').css('display', 'none');
$('#<%= key.to_s + "-message" %>').slideDown().delay(1000).slideUp();
<% end %>
<% end %>

Rails: Killing a Rouge Webrick Server

schleichermann — Mon, 23 May 2011 01:00:35 +0000

If you have ever accidentally closed a terminal window which was running your Rails Webrick server and the server continued to run in the background but you need to kill it so you can restart a new instance you can do the following:

1. run the lsof command identifying port 3000 as the target to get the process ID of the rouge Webrick server

lsof -i:3000

2. then use the kill command plus the process ID you got from step 1 and your rouge will be taken care of.

kill process_id

Of course this is just one way to handle it, if anyone has a better way please comment and let the rest of us know. Thanks in advance!

HTML Special Characters

schleichermann — Mon, 18 Apr 2011 02:43:07 +0000

Latin-1 Entities
				No-break space = non-breaking space
¡	¡	¡	¡	Inverted exclamation mark
¢	¢	¢	¢	Cent sign
£	£	£	£	Pound sign
¤	¤	¤	¤	Currency sign
¥	¥	¥	¥	Yen sign = yuan sign
¦	¦	¦	¦	Broken bar = broken vertical bar
§	§	§	§	Section sign
¨	¨	¨	¨	Diaeresis = spacing diaeresis
©	©	©	©	Copyright sign
ª	ª	ª	ª	Feminine ordinal indicator
«	«	«	«	Left double angle mark = left guillemet
¬	¬	¬	¬	Not sign = discretionary hyphen
				Soft hyphen = discretionary hyphen
®	®	®	®	Registered sign = registered trade mark sign
¯	¯	¯	¯	Macron = overline = APL overbar
°	°	°	°	Degree sign
±	±	±	±	Plus-minus sign = plus-or-minus sign
²	²	²	²	Superscript two = squared
³	³	³	³	Superscript three = cubed
´	´	´	´	Acute accent = spacing acute
µ	µ	µ	µ	Micro sign
¶	¶	¶	¶	Pilcrow sign = paragraph sign
·	·	·	·	Middle dot = Greek middle dot
¸	¸	¸	¸	Cedilla = spacing cedilla
¹	¹	¹	¹	Superscript one = superscript digit one
º	º	º	º	Masculine ordinal indicator
»	»	»	»	Right double angle mark = right guillemet
¼	¼	¼	¼	fraction one quarter
½	½	½	½	fraction one half
¾	¾	¾	¾	fraction three quarters
¿	¿	¿	¿	inverted (turned) question mark
À	À	À	À	Latin capital letter A with grave
Á	Á	Á	Á	Latin capital letter A with acute
Â	Â	Â	Â	Latin capital letter A with circumflex
Ã	Ã	Ã	Ã	Latin capital letter A with tilde
Ä	Ä	Ä	Ä	Latin capital letter A with diaeresis
Å	Å	Å	Å	Latin capital letter A with ring
Æ	Æ	Æ	Æ	Latin capital ligature letter AE
Ç	Ç	Ç	Ç	Latin capital letter C with cedilla
È	È	È	È	Latin capital letter E with grave
É	É	É	É	Latin capital letter E with acute
Ê	Ê	Ê	Ê	Latin capital letter E with circumflex
Ë	Ë	Ë	Ë	Latin capital letter E with diaeresis
Ì	Ì	Ì	Ì	Latin capital letter I with grave
Í	Í	Í	Í	Latin capital letter I with acute
Î	Î	Î	Î	Latin capital letter I with circumflex
Ï	Ï	Ï	Ï	Latin capital letter I with diaeresis
Ð	Ð	Ð	Ð	Latin capital letter ETH
Ñ	Ñ	Ñ	Ñ	Latin capital letter N with tilde
Ò	Ò	Ò	Ò	Latin capital letter O with grave
Ó	Ó	Ó	Ó	Latin capital letter O with acute
Ô	Ô	Ô	Ô	Latin capital letter O with circumflex
Õ	Õ	Õ	Õ	Latin capital letter O with tilde
Ö	Ö	Ö	Ö	Latin capital letter O with diaeresis
×	×	×	×	multiplication sign
Ø	Ø	Ø	Ø	Latin capital letter O with slash
Ù	Ù	Ù	Ù	Latin capital letter U with grave
Ú	Ú	Ú	Ú	Latin capital letter U with acute
Û	Û	Û	Û	Latin capital letter U with circumflex
Ü	Ü	Ü	Ü	Latin capital letter U with diaeresis
Ý	Ý	Ý	Ý	Latin capital letter Y with acute
Þ	Þ	Þ	Þ	Latin capital letter THORN
ß	ß	ß	ß	Latin small letter sharp s = ess-zed
à	à	à	à	Latin small letter a with grave
á	á	á	á	Latin small letter a with acute
â	â	â	â	Latin small letter a with circumflex
ã	ã	ã	ã	Latin small letter a with tilde
ä	ä	ä	ä	Latin small letter a with diaeresis
å	å	å	å	Latin small letter a with ring
æ	æ	æ	æ	Latin small ligature letter ae
ç	ç	ç	ç	Latin small letter c with cedilla
è	è	è	è	Latin small letter e with grave
é	é	é	é	Latin small letter e with acute
ê	ê	ê	ê	Latin small letter e with circumflex
ë	ë	ë	ë	Latin small letter e with diaeresis
ì	ì	ì	ì	Latin small letter i with grave
í	í	í	í	Latin small letter i with acute
î	î	î	î	Latin small letter i with circumflex
ï	ï	ï	ï	Latin small letter i with diaeresis
ð	ð	ð	ð	Latin small letter eth
ñ	ñ	ñ	ñ	Latin small letter n with tilde
ò	ò	ò	ò	Latin small letter o with grave
ó	ó	ó	ó	Latin small letter o with acute
ô	ô	ô	ô	Latin small letter o with circumflex
õ	õ	õ	õ	Latin small letter o with tilde
ö	ö	ö	ö	Latin small letter o with diaeresis
÷	÷	÷	÷	division sign
ø	ø	ø	ø	Latin small letter o with slash
ù	ù	ù	ù	Latin small letter u with grave
ú	ú	ú	ú	Latin small letter u with acute
û	û	û	û	Latin small letter u with circumflex
ü	ü	ü	ü	Latin small letter u with diaeresis
ý	ý	ý	ý	Latin small letter y with acute
þ	þ	þ	þ	Latin small letter thorn
ÿ	ÿ	ÿ	ÿ	Latin small letter y with diaeresis
Symbols and Greek Letters
ƒ	ƒ	ƒ	ƒ	Latin small f with hook = florin
Α	Α	Α	Α	Greek capital letter alpha
Β	Β	Β	Β	Greek capital letter beta
Γ	Γ	Γ	Γ	Greek capital letter gamma
Δ	Δ	Δ	Δ	Greek capital letter delta
Ε	Ε	Ε	Ε	Greek capital letter epsilon
Ζ	Ζ	Ζ	Ζ	Greek capital letter zeta
Η	Η	Η	Η	Greek capital letter eta
Θ	Θ	Θ	Θ	Greek capital letter theta
Ι	Ι	Ι	Ι	Greek capital letter iota
Κ	Κ	Κ	Κ	Greek capital letter kappa
Λ	Λ	Λ	Λ	Greek capital letter lambda
Μ	Μ	Μ	Μ	Greek capital letter mu
Ν	Ν	Ν	Ν	Greek capital letter nu
Ξ	Ξ	Ξ	Ξ	Greek capital letter xi
Ο	Ο	Ο	Ο	Greek capital letter omicron
Π	Π	Π	Π	Greek capital letter pi
Ρ	Ρ	Ρ	Ρ	Greek capital letter rho
Σ	Σ	Σ	Σ	Greek capital letter sigma
Τ	Τ	Τ	Τ	Greek capital letter tau
Υ	Υ	Υ	Υ	Greek capital letter upsilon
Φ	Φ	Φ	Φ	Greek capital letter phi
Χ	Χ	Χ	Χ	Greek capital letter chi
Ψ	Ψ	Ψ	Ψ	Greek capital letter psi
Ω	Ω	Ω	Ω	Greek capital letter omega
α	α	α	α	Greek small letter alpha
β	β	β	β	Greek small letter beta
γ	γ	γ	γ	Greek small letter gamma
δ	δ	δ	δ	Greek small letter delta
ε	ε	ε	ε	Greek small letter epsilon
ζ	ζ	ζ	ζ	Greek small letter zeta
η	η	η	η	Greek small letter eta
θ	θ	θ	θ	Greek small letter theta
ι	ι	ι	ι	Greek small letter iota
κ	κ	κ	κ	Greek small letter kappa
λ	λ	λ	λ	Greek small letter lambda
μ	μ	μ	μ	Greek small letter mu
ν	ν	ν	ν	Greek small letter nu
ξ	ξ	ξ	ξ	Greek small letter xi
ο	ο	ο	ο	Greek small letter omicron
π	π	π	π	Greek small letter pi
ρ	ρ	ρ	ρ	Greek small letter rho
ς	ς	ς	ς	Greek small letter final sigma
σ	σ	σ	σ	Greek small letter sigma
τ	τ	τ	τ	Greek small letter tau
υ	υ	υ	υ	Greek small letter upsilon
φ	φ	φ	φ	Greek small letter phi
χ	χ	χ	χ	Greek small letter chi
ψ	ψ	ψ	ψ	Greek small letter psi
ω	ω	ω	ω	Greek small letter omega
ϑ	ϑ	ϑ	ϑ	Greek small letter theta symbol
ϒ	ϒ	ϒ	ϒ	Greek upsilon with hook symbol
ϖ	ϖ	ϖ	ϖ	Greek pi symbol
•	•	•	•	bullet = black small circle
…	…	…	…	horizontal ellipsis = three dot leader
′	′	′	′	prime = minutes = feet
″	″	″	″	double prime = seconds = inches
‾	‾	‾	‾	overline = spacing overscore
⁄	⁄	⁄	⁄	fraction slash
℘	℘	℘	℘	script capital P = power set = Weierstrass p
ℑ	ℑ	ℑ	ℑ	blackletter capital I = imaginary part
ℜ	ℜ	ℜ	ℜ	blackletter capital R = real part symbol
™	™	™	™	trade mark sign
ℵ	ℵ	ℵ	ℵ	alef symbol = first transfinite cardinal
←	←	←	←	leftwards arrow
↑	↑	↑	↑	upwards arrow
→	→	→	→	rightwards arrow
↓	↓	↓	↓	downwards arrow
↔	↔	↔	↔	left right arrow
↵	↵	↵	↵	down arrow with leftwards corner = CR
⇐	⇐	⇐	⇐	leftwards double arrow
⇑	⇑	⇑	⇑	upwards double arrow
⇒	⇒	⇒	⇒	rightwards double arrow
⇓	⇓	⇓	⇓	downwards double arrow
⇔	⇔	⇔	⇔	left right double arrow
∀	∀	∀	∀	for all
∂	∂	∂	∂	partial differential
∃	∃	∃	∃	there exists
∅	∅	∅	∅	empty set = null set = diameter
∇	∇	∇	∇	nabla = backward difference
∈	∈	∈	∈	element of
∉	∉	∉	∉	not an element of
∋	∋	∋	∋	contains as member
∏	∏	∏	∏	n-ary product = product sign
∑	∑	∑	∑	n-ary sumation
−	−	−	−	minus sign
∗	∗	∗	∗	asterisk operator
√	√	√	√	square root = radical sign
∝	∝	∝	∝	proportional to
∞	∞	∞	∞	infinity
∠	∠	∠	∠	angle
∧	∧	∧	∧	logical and = wedge
∨	∨	∨	∨	logical or = vee
∩	∩	∩	∩	intersection = cap
∪	∪	∪	∪	union = cup
∫	∫	∫	∫	integral
∴	∴	∴	∴	therefore
∼	∼	∼	∼	tilde operator = varies with = similar to
≅	≅	≅	≅	approximately equal to
≈	≈	≈	≈	almost equal to = asymptotic to
≠	≠	≠	≠	not equal to
≡	≡	≡	≡	identical to
≤	≤	≤	≤	less-than or equal to
≥	≥	≥	≥	greater-than or equal to
⊂	⊂	⊂	⊂	subset of
⊃	⊃	⊃	⊃	superset of
⊄	⊄	⊄	⊄	not a subset of
⊆	⊆	⊆	⊆	subset of or equal to
⊇	⊇	⊇	⊇	superset of or equal to
⊕	⊕	⊕	⊕	circled plus = direct sum
⊗	⊗	⊗	⊗	circled times = vector product
⊥	⊥	⊥	⊥	up tack = orthogonal to = perpendicular
⋅	⋅	⋅	⋅	dot operator
⌈	⌈	⌈	⌈	left ceiling = APL upstile
⌉	⌉	⌉	⌉	right ceiling
⌊	⌊	⌊	⌊	left floor = APL downstile
⌋	⌋	⌋	⌋	right floor
⟨	⟨	〈	〈	left-pointing angle bracket = bra
⟩	⟩	〉	〉	right-pointing angle bracket = ket
◊	◊	◊	◊	lozenge
♠	♠	♠	♠	black spade suit
♣	♣	♣	♣	black club suit = shamrock
♥	♥	♥	♥	black heart suit = valentine
♦	♦	♦	♦	black diamond suit
Other special characters
“	"	"	"	quotation mark = APL quote
&	&	&	&	ampersand
<	<	<	<	less-than sign
>	>	>	>	greater-than sign
Œ	Œ	Œ	Œ	Latin capital ligature OE
œ	œ	œ	œ	Latin small ligature oe
Š	Š	Š	Š	Latin capital letter S with caron
š	š	š	š	Latin small letter s with caron
Ÿ	Ÿ	Ÿ	Ÿ	Latin capital letter Y with diaeresis
ˆ	ˆ	ˆ	ˆ	modifier letter circumflex accent
˜	˜	˜	˜	small tilde
				en space
				em space
				thin space
‌	‌	‌	‌	zero width non-joiner
‍	‍	‍	‍	zero width joiner
‎	‎	‎	‎	left-to-right mark
‏	‏	‏	‏	right-to-left mark
–	–	–	–	en dash
—	—	—	—	em dash
‘	‘	‘	‘	left single quotation mark
’	’	’	’	right single quotation mark
‚	‚	‚	‚	single low-9 quotation mark
“	“	“	“	left double quotation mark
”	”	”	”	right double quotation mark
„	„	„	„	double low-9 quotation mark
†	†	†	†	dagger
‡	‡	‡	‡	double dagger
‰	‰	‰	‰	per mille sign
‹	‹	‹	‹	single left-pointing angle quotation mark
›	›	›	›	single right-pointing angle quotation mark
€	€	€	€	euro sign

Dummy/Fake SMTP/Mail Trap for Development Purposes

schleichermann — Wed, 06 Apr 2011 11:55:44 +0000

This post started out as a question on StackOverflow.com (found here). I have moved over to Linux Mint 10 for all of my Ruby and Ruby on Rails application development. I have found this flavour of Linux to be the most pleasant for my purposes. But I ran into a bit of a problem when I first moved over form Windows.

Issue: On windows I had more than one option when it came to a dummy/fake SMTP/Mail trap which I could use to catch and examine the emails generated and sent out by the applications on which I was working. Extremely useful when testing account registration and email activation But on Linux all I found were posts about setting up a full blown SMTP server and then connecting a mail client to it and pulling the emails locally. PUKE, GAG,VOMIT way too much work for me and I am really not interested in becoming a professional mail server administrator.

Solution: After millions of hours searching for a decent solution I ram across a Ruby Gem called MailTrap, oh my saviour, I can’t even begin to tell you how much I love this GEM, it makes my life so much easier.

[sudo] gem install mailtrap

Then don’t forget to setup your development environment file with the following entries

config.action_mailer.raise_delivery_errors = true
config.action_mailer.perform_deliveries = true
config.action_mailer.delivery_method = :smtp
config.action_mailer.smtp_settings = {
:domain => “mydomain.net”,
:address => “localhost”,
:port => 2525,
}
config.action_mailer.default_url_options = { :host => ‘localhost:2525′ }

Then simply run the gem application in a terminal window and you will see each of the mail messages as they come in or you can view them in the log file that is created.

mailtrap run

RVM, Ruby, Rails on Linux Mint

schleichermann — Sat, 26 Mar 2011 07:25:09 +0000

Step 1: First we need to install all the required libraries

$ sudo apt-get install curl git-core build-essential zlib1g-dev libssl-dev libreadline5-dev

Step 2: Install RVM

$ bash < <( curl http://rvm.beginrescueend.com/releases/rvm-install-head )

Step 3: mint 10 does not have a .bashrc file so one needs to be added and then RVM specific lines added

$ sudo touch .bashrc $ sudo gedit .bashrc (Add line to .bashrc file) if [[ -s "$HOME/.rvm/scripts/rvm" ]] ; then source "$HOME/.rvm/scripts/rvm" ; fi

Step 4: close the current terminal and open a new one in order to load the new commands

Step 5: verify RVM has been installed by running you should get back a description of the application written by the author

$ rvm notes

Step 6: now you can install the ruby version of your choice, I am using 1.9.2 so it is compatible with Rails 3

$ rvm install 1.9.2

Step 7: once installed you will need to set the default ruby version to be used by RVM

$ rvm --default ruby-1.9.2

Step 8: verify that the version you selected is now accessible via the standard ruby command

$ ruby -v

Step 9: then use the gem command to install the rails version of your choice

$ gem install rails

Step 10: install MySQL

$ sudo apt-get install libmysql-ruby libmysqlclient-dev
$ gem install mysql2

Fedora 14 64bit Install – Section does not end with %%end.

schleichermann — Mon, 31 Jan 2011 06:19:34 +0000

If you run into the following error while trying to install Fedora 14 on VMware Workstation.

——–

The following error was found while parsing the kickstart configuration file:
The following problem occurred on line 55 of the kickstart file:
Section does not end with %%end.
Install exited abnormally.

——–

It is because VMware is trying to use its automated installation media which is in the first virtual CD/DVD drive and the Fedora ISO is in the second virtual CD/DVD drive.

The issue was resolved when I removed the second virtual CD/DVD drive and then set the first drive to the Fedora ISO.

Rails3: CheatSheet–CommandLine

schleichermann — Mon, 24 Jan 2011 14:46:52 +0000

See the CheatSheet on Google Docs at the following URL:

https://docs.google.com/document/d/1ixObvDQHq9vBD9TTVDmNtigK7LFKu7IyZDy68_k9Z9Q/edit?hl=en&authkey=COzZlYMC