Install Ruby x.y.z

install_ruby_on_cent.sh

#!/bin/sh

# Returns TRUE if $1 doesn't exist. $1 is command name, package name, or the fragment of them.
check_no_cmd()
{
  # Does $PATH include $1?
  which $1
  if [ $? -eq 0 ]; then
    return 1
  fi
  
  # Does $1 exist in installee packages via yum 
  yum list installed | grep $1
  if [ $? -eq 0 ]; then
    return 1
  fi
  
  # Not found
  return 0
}

# for peco, and rbenv
INSTALL_PKG_LIST="wget git gcc gcc-c++ openssl-devel libyaml-devel libffi-devel readline-devel zlib-devel gdbm-devel ncurses-devel"

TO_INSTALL_PKGS=""

for INSTALL_PKG in $INSTALL_PKG_LIST
do
  check_no_cmd ${INSTALL_PKG} && TO_INSTALL_PKGS=${TO_INSTALL_PKGS}"${INSTALL_PKG} "
done

#### SUDO!!
sudo yum install -y ${TO_INSTALL_PKGS}

# peco is very cool interactive grep cli. 
git clone https://github.com/sstephenson/rbenv.git ~/.rbenv

# snippets. plz modify followings if u would like to use /etc/profile
SHELL_NAME=${SHELL##*/}
echo 'export PATH="$HOME/.rbenv/bin:$PATH"' >> ~/.${SHELL_NAME}_profile
echo 'eval "$(rbenv init -)"' >> ~/.${SHELL_NAME}_profile
source ~/.${SHELL_NAME}_profile

rbenv --version

# install ruby-build
git clone https://github.com/sstephenson/ruby-build.git ~/.rbenv/plugins/ruby-build
cd ~/.rbenv/plugins/ruby-build
sudo ./install.sh

cd ~/

# install recent version peco
PECO_URL=`curl -# https://api.github.com/repos/peco/peco/releases|grep browser_download_url|grep linux|grep amd64|grep -vi rc|sed -e 's/"://g' -e 's/"//g'|awk '{print $2}'|head -1`
DL_PECO_FILE=${PECO_URL##*/}
wget PECO_URL
tar xvf DL_PECO_FILE

# peco{hogehoge}.tar.gz => peco{hogehoge}
TEMP_NAME=${DL_PECO_FILE%.*}; PECO_DIR_NAME=${TEMP_NAME%.*}

# interaction
TO_INSTALL_VERSION=`rbenv install --list | ${PECO_DIR_NAME}/peco`

echo "Accept: ${TO_INSTALL_VERSION}"

rbenv install -v ${TO_INSTALL_VERSION}

rbenv rehash
rbenv versions | grep ${TO_INSTALL_VERSION}

if [ $? -eq 0 ]; then
  rbenv global ${TO_INSTALL_VERSION}
  rbenv rehash
fi

ruby -v | grep ${TO_INSTALL_VERSION}

if [ $? -eq 0 ]; then
  echo "Successful: Installed rbenv"
else
  echo "Failure: WTF"
fi