Offer installer.sh for generic installation

README.md

@@ -40,6 +40,7 @@ Use "bns [command] --help" for more information about a command.
 ```
 
 - [Installing](#installing)
+  - [Generic Installer](#generic-installer)
   - [Homebrew](#homebrew)
   - [Downloading a Release from GitHub](#download-github-release)
   - [Docker Hub](#docker-hub)
@@ -49,6 +50,35 @@ Use "bns [command] --help" for more information about a command.
 
 ## Installing
 
+### Generic Installer
+```sh
+installer=$(curl --silent https://raw.githubusercontent.com/bunnyshell/cli/master/installer.sh) \
+    && [ "33cdd268adb1e26511b0cc90c9f4bf017bb145041677ca52d23a0f93cd13bd58 *stdin" = "$(echo -n "${installer}" | openssl dgst -sha256 -r)" ] \
+    && (
+        sh -c "${installer}" || :
+    ) \
+    || echo "Checksum did not match $(echo -n "${installer}" | openssl dgst -sha256 -r)" \
+;
+```
+
+| Env Var         | DEFAULT  | Description               |
+| --------------- | -------- | ------------------------- |
+| DEBUG_INSTALLER | false    | Add set -x for the script |
+| PREFER_BREW     | false    | Allow brew installation   |
+| INSTALL_PATH    | .        | Install path for binary   |
+| SUDO_INSTALL    | false    | Use sudo when moving binary to INSTALL_PATH |
+
+Examples:
+```sh
+installer=$(curl --silent https://raw.githubusercontent.com/bunnyshell/cli/master/installer.sh) \
+    && [ "33cdd268adb1e26511b0cc90c9f4bf017bb145041677ca52d23a0f93cd13bd58 *stdin" = "$(echo -n "${installer}" | openssl dgst -sha256 -r)" ] \
+    && (
+        SUDO_INSTALL=true INSTALL_PATH=/usr/local/bin sh -c "${installer}" || :
+    ) \
+    || echo "Checksum did not match $(echo -n "${installer}" | openssl dgst -sha256 -r)" \
+;
+```
+
 ### Homebrew
 ```sh
 brew install bunnyshell/tap/bunnyshell-cli

installer.sh

@@ -0,0 +1,326 @@
+#!/bin/sh
+# Github release installer
+#
+# Heavily inspired by:
+# - https://github.com/goreleaser/godownloader
+#
+# Shoutout to:
+# - https://www.codetinkerer.com/is-shell-portable/
+# - https://google.github.io/styleguide/shellguide.html although the guide is for BASH not SH
+
+# run in subshell
+(
+    # config
+    BINARY=bns
+    BREW_TAP=bunnyshell/tap/bunnyshell-cli
+    REPOSITORY=bunnyshell/cli
+
+    # install options
+    RELEASE_VERSION=${RELEASE_VERSION:-'latest'}
+    PREFER_BREW=${PREFER_BREW:-false}
+    INSTALL_PATH=${INSTALL_PATH:-.}
+    SUDO_INSTALL=${SUDO_INSTALL:-false}
+
+    if [ "${DEBUG_INSTALLER}" = true ]; then
+        set -x
+    fi
+
+    # main functions
+    main() {
+        if has_brew; then
+            install_with_brew
+        elif is_command "${BINARY}"; then
+            if has_correct_binary; then
+                upgrade;
+            else
+                throw "There is another binary called '${BINARY}' in your PATH"
+            fi
+        else
+            install
+        fi
+    }
+    has_brew() {
+        if [ "${PREFER_BREW}" != true ]; then
+            return 1
+        fi
+
+        is_command brew;
+    }
+    install_with_brew() {
+        log_info 'Using detected brew installation'
+
+        set -x
+
+        brew install "${BREW_TAP}"
+    }
+    upgrade() {
+        INSTALLED_VERSION=$(show_binary_version "${BINARY}")
+
+        log_info "Already installed. ${INSTALLED_VERSION}"
+        tmp_install=$(fetch_binary);EXIT_CODE=$?
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            issue 'Something went wrong with the installation'
+        fi
+
+        UPGRADED_VERSION=$(
+            show_binary_version "${tmp_install}"
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            log_error 'Something went wrong with the installation'
+            issue "Consider manually checking ${tmp_install}"
+        fi
+
+        if [ "${INSTALLED_VERSION}" = "${UPGRADED_VERSION}" ]; then
+            log_info 'You are using the latest version'
+            rm -r "${tmp_install}"
+            exit 0
+        fi
+
+        release "${tmp_install}"
+    }
+
+    install() {
+        log_info 'Fresh install required...'
+
+        tmp_install=$(fetch_binary);EXIT_CODE=$?
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            issue 'Something went wrong with the installation'
+        fi
+
+        release "${tmp_install}"
+    }
+
+    fetch_binary() {
+        if ! is_command tar; then
+            throw 'You need tar binary to unpack github archive'
+        fi
+
+        version=$(github_release_version);EXIT_CODE=$?
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            throw "Installer could not determine version for ${RELEASE_VERSION}."
+        fi
+
+        os=$(goreleaser_os);EXIT_CODE=$?
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            issue "Installer cannot handle OS ${os}"
+        fi
+
+        arch=$(goreleaser_arch);EXIT_CODE=$?
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            issue "Installer cannot handle OS ${os} and ARCH ${arch}"
+        fi
+
+        source="https://github.com/${REPOSITORY}/releases/download/v${version}/${BINARY}_${version}_${os}_${arch}.tar.gz"
+
+        github_download "$source"
+    }
+
+    release() {
+        tmp_install=$1
+        maybe_sudo=''
+        if [ "${SUDO_INSTALL}" = true ]; then
+            maybe_sudo='sudo'
+            log_info 'Detected SUDO_INSTALL. Password might be required...'
+        fi
+
+        install_file="${INSTALL_PATH}/${BINARY}"
+
+        RESULT=$(
+            ${maybe_sudo} mv "${tmp_install}" "${install_file}" \
+                \
+                2>&1 \
+            ;
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            throw "${RESULT}"
+        fi
+
+        log_info "Installed '${BINARY}' in ${INSTALL_PATH}"
+        log_info "$(show_binary_version "${install_file}")"
+
+        if ! is_command "${BINARY}"; then
+            absolute_install_path=$(realpath "${INSTALL_PATH}")
+            update_path=$(
+                printf 'You will need to update your %sPATH variable or run "mv %s %s"' '$' "${absolute_install_path}/${BINARY}" '/usr/local/bin'
+            )
+            log_info "${update_path}"
+        fi
+    }
+
+    # binary functions
+    has_correct_binary() {
+        HEADER=$(
+            ${BINARY} --help | head -1
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            return 1
+        fi
+
+        case $HEADER in
+            ("Bunnyshell CLI"*) return 0 ;;
+            *) return 1 ;;
+        esac
+    }
+    show_binary_version() {
+        $1 version --client=true
+    }
+
+    # goreleaser binary naming from .goreleaser.yaml
+    goreleaser_os() {
+        os=$(uname -s | tr '[:upper:]' '[:lower:]')
+        case $os in
+            darwin) echo "Darwin" ;;
+            linux) echo "Linux" ;;
+            *) echo "${os}"; return 1;
+        esac
+    }
+    goreleaser_arch() {
+        arch=$(uname -m)
+        case $arch in
+            x86_64) echo 'x86_64' ;;
+            i386) echo 'i386' ;;
+            aarch64) echo 'arm64' ;;
+            arm64) echo 'arm64' ;;
+            *) echo "${arch}"; return 1;
+        esac
+    }
+
+    # fetcher logic
+    fetch() {
+        source_url=$1
+        tmp=$(tmp_file)
+        echo "${tmp}"
+
+        download "$source_url" "${tmp}"
+    }
+    fetch_response() {
+        tmp=$(fetch "$1");
+        cat "${tmp}"
+        rm -rf "${tmp}"
+    }
+    download() {
+        if is_command curl; then
+            download_with_curl "$1" "$2"
+        elif is_command wget; then
+            download_with_wget "$1" "$2"
+        else
+            throw 'You need either curl or wget to download remote files'
+        fi
+    }
+    download_with_curl() {
+        source_url=$1
+        local_file=$2
+
+        RESPONSE=$(
+            curl "$source_url" --silent --location --fail \
+                --output "$local_file"\
+                --header 'Accept: application/json' \
+            ;
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            throw "Could not download ${source_url} to ${local_file}: ${RESPONSE}"
+        fi
+
+        return 0
+    }
+    download_with_wget() {
+        source_url=$1
+        local_file=$2
+
+        RESPONSE=$(
+            wget "$source_url" --quiet \
+                --output "$local_file" \
+                --header 'Accept: application/json' \
+            ;
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            throw "Could not download ${source_url} to ${local_file}: ${RESPONSE}"
+        fi
+
+        return 0
+    }
+
+    # github operations
+    github_extract_binary() {
+        archive=$1
+
+        extract_dir=$(tmp_dir)
+
+        result=$(
+            tar --extract --gzip \
+                --directory "${extract_dir}" \
+                --file "${archive}" \
+                ${BINARY} \
+                \
+                2>&1 \
+            ;
+        );EXIT_CODE=$?
+
+        if [ "${EXIT_CODE}" -ne 0 ]; then
+            issue "Could not extract ${BINARY}: ${result}"
+        fi
+
+        tmp_binary=$(tmp_file)
+        mv "${extract_dir}/${BINARY}" "${tmp_binary}"
+        rm -r "${extract_dir}"
+        echo "${tmp_binary}"
+    }
+    github_download() {
+        tmp_archive=$(fetch "$1") || throw 'Could not download archive'
+        tmp_binary=$(github_extract_binary "${tmp_archive}")
+        rm -rf "${tmp_archive}"
+
+        echo "${tmp_binary}"
+    }
+    github_release_version() {
+        json=$(fetch_response "https://github.com/${REPOSITORY}/releases/${RELEASE_VERSION}")
+
+        test -z "${json}" && return 1
+        version=$(
+            echo "${json}" \
+                | tr -s '\n' ' ' \
+                | sed 's/.*"tag_name":"v//' \
+                | sed 's/".*//' \
+            ;
+        )
+
+        test -z "${version}" && return 1
+        echo "${version}"
+    }
+
+    # helpers
+    tmp_dir() {
+        mktemp --quiet --directory
+    }
+    tmp_file() {
+        mktemp --quiet
+    }
+    issue() {
+        log_error "$@"
+        log_error "Let us know: https://github.com/${REPOSITORY}/issues"
+
+        exit 2
+    }
+    throw() {
+        log_error "$@"
+
+        exit 1
+    }
+    log_error() {
+        echo '[ERROR]' "$@" >&2
+    }
+    log_info() {
+        echo '[INFO]' "$@"
+    }
+
+    is_command() {
+        command -v "$1" > /dev/null
+    }
+
+    main "$@"
+)