dotnet-installer/scripts/install.sh

#!/usr/bin/env sh

#setup some colors to use. These need to work in fairly limited shells, like the Ubuntu Docker container where there are only 8 colors.
#See if stdout is a terminal
if [ -t 1 ]; then
    # see if it supports colors
    ncolors=$(tput colors)
    if [ -n "$ncolors" ] && [ $ncolors -ge 8 ]; then
        bold="$(tput bold)"
        normal="$(tput sgr0)"
        black="$(tput setaf 0)"
        red="$(tput setaf 1)"
        green="$(tput setaf 2)"
        yellow="$(tput setaf 3)"
        blue="$(tput setaf 4)"
        magenta="$(tput setaf 5)"
        cyan="$(tput setaf 6)"
        white="$(tput setaf 7)"
    fi
fi

#Standardise OS name to what is put into filenames of the tarballs.
__current_os()
{
    local uname=$(uname)
    if [ "$uname" = "Darwin" ]; then
        echo "osx"
    else
        echo "linux"
    fi
}

__machine_has() {
    type "$1" > /dev/null 2>&1
    return $?
}

#Not 100% sure at the moment that these checks are enough. We might need to take version into account or do something
#more complicated. This seemed like a good beginning though as it should catch the default "clean" machine case and give
#people an appropriate hint.
__check_pre_reqs() {
    local os=$(__current_os)
    local _failing=false;
    if [ "$os" = "linux" ]; then
        [ -z "$(ldconfig -p | grep libunwind)" ] && say_err "Unable to locate libunwind. Install libunwind to continue" && _failing=true
        [ -z "$(ldconfig -p | grep libssl)" ] && say_err "Unable to locate libssl. Install libssl to continue" && _failing=true
        [ -z "$(ldconfig -p | grep libcurl)" ] && say_err "Unable to locate libcurl. Install libcurl to continue" && _failing=true
        [ -z "$(ldconfig -p | grep libicu)" ] && say_err "Unable to locate libicu. Install libicu to continue" && _failing=true
        [ -z "$(ldconfig -p | grep gettext)" ] && say_err "Unable to locate gettext. Install libicu to gettext" && _failing=true
    fi
    
    if [ "$_failing" = true ]; then
       return 1
    fi
}

say_err() {
    printf "%b\n" "${red}dotnet_install: Error: $1${normal}" >&2
}

say() {
    printf "%b\n" "dotnet_install: $1"
}

_install_dotnet()
{
    if ! __machine_has "curl"; then
        printf "%b\n" "${red}curl is required to download dotnet. Install curl to proceed. ${normal}" >&2;
        return 1
    fi
    
    if [ -e "/usr/local/share/dotnet/cli/dotnet" ] && [ ! -w "/usr/local/share/dotnet/cli/dotnet" ]; then
        say_err "It looks like you already have the dotnet cli and it isn't writeable. If you are sure that you want to install the cli over the top of the currently installed version then run this command again with sudo."
        say_err "If you have previously installed the cli using a pkg then that is why it is write protected, and you need to run sudo to install the new version."
        say_err "Alternatively, removing the '/usr/local/share/dotnet' directory completely before running the script will also resolve the issue."
        return 1
    fi

    __check_pre_reqs
    if [ $? != 0 ]; then
        say_err "Ending install due to missing pre-reqs"
        return 1;
    fi

    local installLocation="/usr/local/share/dotnet"
    local dotnet_url="https://dotnetcli.blob.core.windows.net/dotnet/dev/Binaries/Latest"
    local dotnet_filename="dotnet-$(__current_os)-x64.latest.tar.gz"

    #This should noop if the directory already exists.
    mkdir -p $installLocation

    say "Downloading $dotnet_filename from $dotnet_url"

    #Download file and check status code, error and return if we cannot download a cli tar.
    local httpResult=$(curl -L -D - "$dotnet_url/$dotnet_filename" -o "$installLocation/$dotnet_filename" -# | grep "^HTTP/1.1" | head -n 1 | sed "s/HTTP.1.1 \([0-9]*\).*/\1/")
    [ $httpResult -ne "302" ] && [ $httpResult -ne "200" ] && echo "${Red}HTTP Error $httpResult fetching the dotnet cli from $dotnet_url ${RCol}" && return 1

    say "Extracting tarball"
    #Any of these could fail for various reasons so we will check each one and end the script there if it fails.
    rm -rf "$installLocation/cli_new"
    mkdir "$installLocation/cli_new"
    [ $? != 0 ] && say_err "failed to clean and create temporary cli directory to extract into" && return 1
    
    tar -xzf "$installLocation/$dotnet_filename" -C "$installLocation/cli_new"
    [ $? != 0 ] && say_err "failed to extract tar" && return 1
    
    say "Moving new CLI into install location and symlinking"

    rm -rf "$installLocation/cli"
    [ $? != 0 ] && say_err "Failed to clean current dotnet install" && return 1

    mv "$installLocation/cli_new" "$installLocation/cli"

    for f in $(find "$installLocation/cli" -regex ".*/dotnet[a-z\-]*$")
    do
        local baseFile=$(basename $f)
        if [ -e "/usr/local/bin/$baseFile" ]; then
            say "${yellow}$baseFile already exists in /usr/local/bin. Skipping symlink...${normal}"
        else
            say "linking $baseFile"
            ln -s $f /usr/local/bin/
        fi
    done
    
    say "Cleaning $dotnet_filename"
    rm "$installLocation/$dotnet_filename"
    [ $? != 0 ] && say_err "Failed to delete tar after extracting." && return 1
}

_install_dotnet