Add install script (#558)

docs/README.md

@@ -24,7 +24,13 @@ brew tap tufin/homebrew-tufin
 brew install oasdiff
 ```
 
-### Install on macOS, Windows and Linux
+### Install on macOS and Linux using curl
+
+```bash
+curl -fsSL https://raw.githubusercontent.com/tufin/oasdiff/main/install.sh | sh
+```
+
+### Manually install on macOS, Windows and Linux
 Copy binaries from [latest release](https://github.com/Tufin/oasdiff/releases/)
 
 

install.sh

@@ -0,0 +1,148 @@
+#!/bin/sh
+set -e
+
+# Adapted from https://raw.githubusercontent.com/railwayapp/cli/master/install.sh
+#
+# oasdiff
+# https://github.com/Tufin/oasdiff
+
+
+INSTALL_DIR=${INSTALL_DIR:-"/usr/local/bin"}
+BINARY_NAME=${BINARY_NAME:-"oasdiff"}
+
+REPO_NAME="Tufin/oasdiff"
+ISSUE_URL="https://github.com/Tufin/oasdiff/issues/new"
+
+get_latest_release() {
+  curl --silent "https://api.github.com/repos/$1/releases/latest" | # Get latest release from GitHub api
+    grep '"tag_name":' |                                            # Get tag line
+    sed -E 's/.*"([^"]+)".*/\1/'                                    # Pluck JSON value
+}
+
+get_asset_name() {
+  echo "oasdiff_$1_$2_$3.tar.gz"
+}
+
+get_download_url() {
+  local asset_name=$(get_asset_name $1 $2 $3)
+  echo "https://github.com/Tufin/oasdiff/releases/download/v$1/${asset_name}"
+}
+
+get_checksum_url() {
+  echo "https://github.com/Tufin/oasdiff/releases/download/v$1/checksums.txt"
+}
+
+command_exists() {
+  command -v "$@" >/dev/null 2>&1
+}
+
+get_os() {
+  case "$(uname -s)" in
+    *linux* ) echo "linux" ;;
+    *Linux* ) echo "linux" ;;
+    *darwin* ) echo "darwin" ;;
+    *Darwin* ) echo "darwin" ;;
+  esac
+}
+
+get_machine() {
+  case "$(uname -m)" in
+    "x86_64"|"amd64"|"x64")
+      echo "x86_64" ;;
+    "i386"|"i86pc"|"x86"|"i686")
+      echo "i386" ;;
+    "arm64"|"armv6l"|"aarch64")
+      echo "arm64"
+  esac
+}
+
+get_tmp_dir() {
+  echo $(mktemp -d)
+}
+
+do_checksum() {
+  echo "Validating checksum"
+  checksum_url=$(get_checksum_url $version)
+  get_checksum_url $version
+  expected_checksum=$(curl -sL $checksum_url | grep $asset_name | awk '{print $1}')
+
+  if command_exists sha256sum; then
+    checksum=$(sha256sum $asset_name | awk '{print $1}')
+  elif command_exists shasum; then
+    checksum=$(shasum -a 256 $asset_name | awk '{print $1}')
+  else
+    echo "Could not find a checksum program. Install shasum or sha256sum to validate checksum."
+    return 0
+  fi
+
+  if [ "$checksum" != "$expected_checksum" ]; then
+    echo "Checksums do not match"
+    exit 1
+  fi
+}
+
+do_install() {
+  asset_name=$(get_asset_name $version $os $machine)
+  download_url=$(get_download_url $version $os $machine)
+
+  command_exists curl || {
+    echo "curl is not installed"
+    exit 1
+  }
+
+  command_exists tar || {
+    echo "tar is not installed"
+    exit 1
+  }
+
+  local tmp_dir=$(get_tmp_dir)
+  echo "Temporary directory is $tmp_dir"
+
+  echo "Downloading $download_url"
+  (cd $tmp_dir && curl -sL -O "$download_url")
+
+  (cd $tmp_dir && do_checksum)
+
+  echo "Extracting tar file"
+  (cd $tmp_dir && tar -xzf "$asset_name")
+
+  echo "Installing $BINARY_NAME into $tmp_dir"
+  mv "$tmp_dir/$BINARY_NAME" $INSTALL_DIR
+
+  chmod +x $INSTALL_DIR/$BINARY_NAME
+  echo "Installed oasdiff to $INSTALL_DIR"
+
+  echo "Removing temporary directory"
+  rm -rf $tmp_dir
+}
+
+main() {
+  latest_tag=$(get_latest_release $REPO_NAME)
+  version=$(echo $latest_tag | sed 's/v//')
+
+  os=$(get_os)
+  if test -z "$os"; then
+    echo "$(uname -s) os type is not supported"
+    echo "Please create an issue so we can add support. $ISSUE_URL"
+    exit 1
+  fi
+
+  if [ "$os" == "darwin" ]; then
+    machine="all"
+  else
+    machine=$(get_machine)
+  fi
+
+  if test -z "$machine"; then
+    echo "$(uname -m) machine type is not supported"
+    echo "Please create an issue so we can add support. $ISSUE_URL"
+    exit 1
+  fi
+
+  do_install
+
+  echo "oasdiff is now installed! type 'oasdiff -h' to see a list of commands"
+
+}
+
+main