Bash utilities for setup scripts.

_utils.bash

# _utils.bash --- Utilities used across all the scripts.

ERROR_FILE="/tmp/setup_script_error.msg"

# Checks if user has cowsay installed, and if it does
# then uses it to display the message.
cowsay_or_echo()
{
    cowsay=`which cowsay`
    cowsay_eyes=$1; shift

    if [ "$cowsay" != "" ]; then
        echo $@ | $cowsay -e $cowsay_eyes -W 60
    else
        echo $@
    fi
}

# A wrapper for commands. If command fail, then clear
# error message will be displayed and execution stopped.
#
# Usage:
#
#   setup assert_command ruby git
#   setup assert_ruby_version 1.9.3
#
setup()
{
    $@ 2>&1 | sed -e "s/^/       /"

    if [ -f $ERROR_FILE ]; then
        echo -e "-----> Aborting...\n"
        echo -e "\033[31m$(cowsay_or_echo xX $(cat $ERROR_FILE))\033[0m\n"

        rm -f $ERROR_FILE
        exit 1
    fi
}

# Stores information about the current error.
set_error()
{
    cat $@ > $ERROR_FILE
}

# Displays final success message.
success()
{
    msg=`cat $@`
    echo -e "\033[32m$(cowsay_or_echo ^^ $msg)\033[0m\n"
}

# Checks if command in the first agument is available
# in the host system.
#
# Usage:
#
#   assert_command git
#
assert_command()
{
    cmd="$1"
    err=""

    command -v $cmd >/dev/null 2>&1 || err=1

    if [ $err ]; then
        echo "$cmd: Command required but not found. Aborting."
        set_error <<EOF
In order to continue you have to install a package which provides
the $cmd command.
EOF
        return 1
    fi

    echo "$cmd: $(command -v $cmd)";
}

# Checks if all specified commands are available in the
# host system.
#
# Usage:
#
#   assert_command git ruby mysql
#
assert_commands()
{
    commands="$@"

    for cmd in $commands; do
        assert_command $cmd || break
    done
}

# Checks if ruby version is correct.
#
# Usage:
#
#   assert_ruby_version 1.9.3
#
assert_ruby_version()
{
    version=$1
    ruby -e 'RUBY_VERSION >= "$1" or exit 1' 2>&1; err=$?
    ruby -v

    if [ $err -ne 0 ]; then
        set_error <<EOF
In order to continue you must install ruby in version $version or higher.
EOF
        return 1
    fi
}

# Works the same as assert_ruby_version but checks the version
# of installed python interpreter.
assert_python_version() {
    version=$1
    ruby -e '`python --version 2>&1`.split.last >= "$1" or exit 1' 2>&1; err=$?
    python --version

    if [ $err -ne 0 ]; then
        set_error <<EOF
In order to continue you must install python in version $version or higher.
EOF
    fi
}

# Installs ruby dependencies via bundler.
install_dependencies_via_bundler()
{
    bundle install

    if [ $? -ne 0 ]; then
        set_error <<EOF
Bundler failed to install gem dependencies.
EOF
    fi
}

# Checks if there's an .env file in the root directory, and if
# not, it makes a copy of .env.sample and lets user edit its
# content.
edit_env_configs()
{
    if [ "$EDITOR" == "" ]; then
        echo "Editor is not set."
        set_error <<-EOF
You don't have editor set. Set it like this:

    $ export EDITOR=emacs

You may want to add this line to your ~/.bashrc file. You can also
run this script with inline EDITOR variable.
EOF
        return
    fi

    if [ ! -f .env ]; then
        cp .env.sample .env
        echo "File doesn't exist: .env, copying from .env.sample"
        echo "Opening editor..."
        $EDITOR .env || true
    else
        echo "File exists: .env"
    fi
}