Category: Ruby On Rails

Rails mysql2 gem getting error checking for mysql_query() in -lmysqlclient… no

Make sure that you have installed mysql server and mysql client. Else install by

$ sudo apt-get install mysql-server
$ sudo apt-get install mysql-client

After that install the dependency library for mysql

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

Use Ruby Metrical Gem for reviewing your rails code and find the rails best practises with rails_best_practices gem

Install the metrical gem first to run metrical.

$ gem install metrical

If the output showing an error like: Gem::DependencyError, then install the gem metric_fu first, which installs all the dependencies required.

$ gem install metric_fu

Then try to install the metrical gem

I got the following error:

vnet6@ubuntu:~/projects/grouptable$ gem install metrical
ERROR:  While executing gem ... (Gem::DependencyError)
    Unable to resolve dependencies: metric_fu requires sexp_processor (~> 3.0.3); churn requires sexp_processor (~> 3.0); reek requires sexp_processor (~> 3.0); ruby2ruby requires sexp_processor (~> 3.0); ripper_ruby_parser requires sexp_processor (~> 3.0); flog requires sexp_processor (~> 3.0); ruby_parser requires sexp_processor (~> 3.0)

In my system sexp_processor version was (4.2.1)

I uninstalled the version,

$ gem uninstall sexp_processor

and installed the version 3.0.3

$ gem list sexp_processor -v '3.0.3'

and installed the metrical gem by

$ gem install metrical

run metrical gem by

$ metrical

But this is also giving me error! It has a lot of dependencies. It is asking again the sexp_processor version (4.2.1). So Installed two versions so the error gone and got another error!

So I tried the rails_best_practices to see the warnings.

$ gem install rails_best_practices
$ rails_best_practices
$ rails_best_practices -f html # to see the warnings in html

Its working fine!

mongodb connection issue: `connect’: Failed to connect to a master node at localhost:27017 (Mongo::ConnectionFailure)

You just try to start the mongodb by

service mongod start

or

start mongod

And check mongodb process is running by checking

ps aux | grep mongo

You can see the status by

service mongod status

If it is not starting then try to remove the mongod lock file by,

rm /var/lib/mongodb/mongod.lock

Then start the mongodb server again.

Install RVM, Ruby on CentOS

First download the Ruby Version Manager (RVM) installer as follows

$ sudo bash -s stable < <(curl -s https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer )

RVM requires to add relevant users to it’s group. Open the file like so:

$ sudo vim /etc/group

Edit the ‘rvm’ group (likely the last entry) to look like:

rvm:x:503:your_username
Run the install:

$ cd /usr/local/rvm/bin
$ sudo ./rvm-installer
...

“Upgrade of RVM in /usr/local/rvm/ is complete.”

I needed to reload the RVM to continue, this might not be required:

$ rvm reload

If it shows -bash: rvm: command not found

please close the terminal and start it again to load the RVM.

Now we can install the Ruby version. This will also install rubygems which is always useful…

$ rvm install 1.9.3 --with-openssl-dir=/usr
$ ruby -v
$ rvm use ruby-1.9.3-p327 --default

If you are getting nokogiri error like:

Gem::Installer::ExtensionBuildError: ERROR: Failed to build gem native extension.

checking for libxslt/xslt.h… no

libxslt is missing.

then install

$ sudo yum install -y gcc ruby-devel libxml2 libxml2-devel libxslt libxslt-devel

Reference:
http://jamesmcfadden.co.uk/installing-ruby-on-rails-on-centos-5-8/

Rails gem therubyracer installation error: extconf.rb:10:in `’: Error compiling V8 (RuntimeError)

It is because of you have already the old version of therubyracer is in your project. And that version depends on a libv8 gem, thats why it is getting error so, uninstall the libv8 gem and install the therubyracer again

$ gem uninstall libv8
$ gem install therubyracer

A Simple example of Using iframe in Rails

Write the code for iframe and in the src option give the path that defined in routes. It will render the file which corresponding action of the controller renders.

An Haml example is given below:

%iframe{:align => "center", :name => "window", :src => "#{list_make_shipments_path(:ids => "#{@shipment_success_responses.collect(&:id).join(",")}")}", :height => "1000px;", :width => "1100px;", :style => "float:left;margin-top:30px;"}

Importing contacts from your email using Rails ‘contacts’ gem

Using ‘contacts’ gem you can import all your contact emails.

Step 1:

In Your Gemfile add,

## For Importing Email Contacts
gem "contacts", :git => "git://github.com/abhilashak/contacts.git"
gem "gdata", :git => "git://github.com/abhilashak/gdata-1.git"

For importing from gmail, we need the gem ‘gdata’.

Do bundle install

you are done.

Step 2:

In your views/import_profile_contact/new.html.erb file,

<%=  text_field_tag "profile_contact[email]", "" %>

<%=  password_field_tag "profile_contact[password]", "" %>

Put one more hidden field tag to know that from which email the user need to import

<%= hidden_field_tag :contact_from, @contact_from %>

the values of @contact_from may be gmail, yahoo mail, hot mail. According to which option user clicks pass the corresponding string.

Step 3:

In your controller get the email and password params

@contact_from = params[:contact_from]

email = params[:profile_contact][:email]
password = params[:profile_contact][:password]

if @contact_from && email && password
  if @contact_from == "gmail"
    @imported_contacts = Contacts.new(:gmail, email, password).contacts
  elsif @contact_from == "yahoo_mail"
    @imported_contacts = Contacts.new(:yahoo, email, password).contacts
  elsif @contact_from == "hotmail"
    @imported_contacts = Contacts.new(:hotmail, email, password).contacts
  end
end

You will get all contacts in an array….