install_nginx.sh

 

      		
    

    

      
        

          
        

        
Convenience Functions

      		
      
        

      		
    

    

      
        

          
        

        
Set up a simple function to print logging info so that the user
can follow the script output

      		
      
        
log() { printf "===> $*\n" ; return $? ; }

      		
    

    

      
        

          
        

        
A quick function to handle error-and-quit situtations.

      		
      
        
fail()  { printf "\n>> ERROR: $*\n\n" ; exit 1 ; }

      		
    

    

      
        

          
        

        
Ensure that the calling user is root and fail otherwise. This
way we don’t need to worry about which commands require sudo.

      		
      
        
[[ $UID -ne 0 ]] && fail "You must be root to run this installer"

      		
    

    

      
        

          
        

        
Variables

      		
      
        

      		
    

    

      
        

          
        

        
The directory that tarballs will be downloaded to.

      		
      
        
cache_dir="/var/cache/downloads"

      		
    

    

      
        

          
        

        
The full URL to download the nginx tarball.

      		
      
        
tar_url="http://nginx.org/download/nginx-0.9.7.tar.gz"

      		
    

    

      
        

          
        

        
The name of the tarball without the URL at the beggining. There
is some Bash variable manging going on here with
string operators.

      		
      
        
tar_file="${tar_url##http*/}"

      		
    

    

      
        

          
        

        
The directory that will get created when extracting the tarball.
Same variable mangling tricks here too (strip .tar.gz off the
end of $tar_file).

      		
      
        
tar_dir="${tar_file%.tar.gz}"

      		
    

    

      
        

          
        

        
The configure flags used when configuring nginx. We’re targetting
a custom directory in /opt so that multiple built versions of
nginx can co-exist together. We’re also enabling the SSL module
which is bound to be used sooner or later.

      		
      
        
configure_flags="
  --prefix=/opt/${tar_dir}
  --conf-path=/etc/nginx/nginx.conf
  --with-http_ssl_module
"

      		
    

    

      
        

          
        

        
A list of Ubuntu packages that must be installed prior to
compiling nginx. We also want the wget package to fetch
the tarball. It’s installed by default in Ubuntu base, but
no harm in being explicit.

      		
      
        
pkgs=( wget build-essential binutils-doc autoconf flex bison
       libpcre3 libpcre3-dev libssl-dev )

      		
    

    

      
        

          
        

        
Install Pre-requisite Packages

      		
      
        

      		
    

    

      
        

          
        

        
Loop through the $pkgs array and install each package
on its own. We could have done this as one command but
installing individually might help us catch any errors
and zero in on the bad package.

      		
      
        
log "Installing packages"
for pkg in "${pkgs[@]}" ; do
  log "Installing ${pkg}..."
  apt-get install -y $pkg
done ; unset pkg

      		
    

    

      
        

          
        

        
Fetching and Extraction

      		
      
        

      		
    

    

      
        

          
        

        
Ensure that the $cache_dir directory exists and has
sane permissions and ownership. The -p flag in mkdir
will create any missing parent directories.

      		
      
        
log "Creating a download cache directory in $cache_dir"
mkdir -p $cache_dir
chown root:root $cache_dir
chmod 755 $cache_dir

      		
    

    

      
        

          
        

        
Download the the nginx tarball into the $cache_dir
directory. First, we’ll remove any pre-existing tarballs
so that wget won’t download the tarball to a different
file (appending .1 to the end which is lamesauce for
our use case).

      		
      
        
log "Downloading nginx tarball from $tar_url"
rm -f $cache_dir/$tar_file
(cd $cache_dir && wget $tar_url)

      		
    

    

      
        

          
        

        
Next, extract the downloaded tarball into $cache_dir
so we have a place to build it. We’ll also kill any
old extracted directories.

      		
      
        
log "Extracting nginx tarball into $cache_dir"
rm -rf $cache_dir/$tar_dir
(cd $cache_dir && tar zxf $tar_file)

      		
    

    

      
        

          
        

        
Compilation and Installation

      		
      
        

      		
    

    

      
        

          
        

        
The most likely place for something to go wrong :) nginx
follows a very standard (and sane) build process of running
./configure ..., then make and make install.

      		
      
        
log "Building nginx"
(cd $cache_dir/$tar_dir && ./configure $configure_flags)
(cd $cache_dir/$tar_dir && make && make install)

      		
    

    

      
        

          
        

        
Now we’ll loop through a few directories that need to exist
for nginx to start.

      		
      
        
for dir in /var/log/nginx /etc/nginx/{conf.d,sites-enabled} ; do
  log "Creating $dir directory..."
  mkdir -p $dir
  chown root:root $dir
  chmod 755 $dir
done ; unset dir

      		
    

    

      
        

          
        

        
Download an nginx config file off GitHub to make this script
a little more portable.

      		
      
        
log "Installing /etc/nginx/nginx.conf..."
wget --no-check-certificate \
  'https://gist.github.com/raw/924883/nginx.conf' \
  -O /etc/nginx/nginx.conf
chown root:root /etc/nginx/nginx.conf
chmod 644 /etc/nginx/nginx.conf

      		
    

    

      
        

          
        

        
Download a default nginx site definition so we can display
a pretty web page.

      		
      
        
log "Installing /etc/nginx/sites-enabled/_default.conf..."
wget --no-check-certificate \
  'https://gist.github.com/raw/924883/default-site.conf' \
  -O /etc/nginx/sites-enabled/_default.conf
chown root:root /etc/nginx/sites-enabled/_default.conf
chmod 644 /etc/nginx/sites-enabled/_default.conf

      		
    

    

      
        

          
        

        
Download an init.d rc script so nginx is like any other
service and comes back on reboot.

      		
      
        
log "Installing /etc/init.d/nginx..."
wget --no-check-certificate \
  'https://gist.github.com/raw/924883/nginx.init.sh' \
  -O /etc/init.d/nginx
chown root:root /etc/init.d/nginx
chmod 755 /etc/init.d/nginx

      		
    

    

      
        

          
        

        
Finally, register the nginx service and start it up.

      		
      
        
log "Starting the nginx daemon..."
/usr/sbin/update-rc.d -f nginx defaults
service nginx start

      		
    

    

      
        

          
        

        
And that’s it, thanks for playing along.


      		
      
        
log "Installation of nginx is complete, w00t\!"