add installer script

Author: dwgnr

install.sh

@@ -0,0 +1,125 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+REPO="th-nuernberg/usermgmt"
+DEFAULT_INSTALL_DIR="/usr/local/bin"
+
+usage(){
+  cat <<EOF
+Usage: $0 [TAG] [INSTALL_DIR]
+TAG: optional GitHub release tag (e.g. v0.6.3). If omitted, it uses latest.
+INSTALL_DIR: optional install directory (default: ${DEFAULT_INSTALL_DIR})
+EOF
+}
+
+
+if [[ "${1:-}" == "-h" || "${1:-}" == "--help" ]]; then
+  usage
+  exit 0
+fi
+
+if [ "$#" -gt 2 ]; then
+  usage
+  exit 1
+fi
+
+TAG="${1:-latest}"
+INSTALL_DIR="${2:-$DEFAULT_INSTALL_DIR}"
+
+OS="$(uname -s)"
+case "$OS" in
+  Darwin) PLATFORM="mac" ;;
+  Linux)  PLATFORM="linux" ;;
+  *)
+    echo "Unsupported OS: $OS" >&2
+    exit 2
+    ;;
+esac
+
+if [ "$PLATFORM" = "mac" ]; then
+  ASSET="usermgmt-aarch64-apple-darwin.tar.gz"
+elif [ "$PLATFORM" = "linux" ]; then
+  ASSET="usermgmt-x86_64-unknown-linux-gnu.tar.gz"
+fi
+
+# Resolve tag (if latest, follow GitHub redirect to get actual tag)
+if [ "$TAG" = "latest" ]; then
+  echo "Resolving latest release tag..."
+  final_url=$(curl -fsSL -o /dev/null -w '%{url_effective}' "https://github.com/${REPO}/releases/latest")
+  TAG="$(basename "$final_url")"
+  if [ -z "$TAG" ]; then
+    echo "Failed to resolve latest release tag." >&2
+    exit 3
+  fi
+  echo "Latest tag is: $TAG"
+fi
+
+DOWNLOAD_URL="https://github.com/${REPO}/releases/download/${TAG}/${ASSET}"
+echo "Will download: $DOWNLOAD_URL"
+
+for cmd in curl tar; do
+  if ! command -v "$cmd" >/dev/null 2>&1; then
+    echo "Required tool '$cmd' not found. Install it and re-run." >&2
+    exit 4
+  fi
+done
+
+tmpdir="$(mktemp -d)"
+cleanup(){ rm -rf "$tmpdir"; }
+trap cleanup EXIT
+
+outfile="$tmpdir/$ASSET"
+
+echo "Downloading asset..."
+if ! curl -fL --progress-bar -o "$outfile" "$DOWNLOAD_URL"; then
+  echo "Download failed. Check tag ($TAG) and that asset exists: $ASSET" >&2
+  exit 5
+fi
+
+echo "Extracting..."
+tar -xzf "$outfile" -C "$tmpdir"
+
+# locate executable: prefer file named 'usermgmt', otherwise first executable file found
+found="$(find "$tmpdir" -type f -name 'usermgmt' -perm -111 -print -quit 2>/dev/null || true)"
+if [ -z "$found" ]; then
+  found="$(find "$tmpdir" -type f -perm -111 -print -quit 2>/dev/null || true)"
+fi
+
+if [ -z "$found" ]; then
+  echo "Could not find an executable inside the archive." >&2
+  echo "Archive contents:" >&2
+  find "$tmpdir" -ls >&2 || true
+  exit 6
+fi
+
+echo "Found executable: $found"
+
+if [ ! -d "$INSTALL_DIR" ]; then
+  echo "Creating install dir: $INSTALL_DIR"
+  mkdir -p "$INSTALL_DIR"
+fi
+
+dst="$INSTALL_DIR/usermgmt"
+echo "Installing to $dst"
+
+if [ -w "$INSTALL_DIR" ]; then
+  cp -f "$found" "$dst"
+  chmod +x "$dst"
+else
+  echo "Need sudo to write to $INSTALL_DIR"
+  sudo cp -f "$found" "$dst"
+  sudo chmod +x "$dst"
+fi
+
+if ! echo "$PATH" | tr ':' '\n' | grep -qx "$INSTALL_DIR"; then
+  echo "Warning: $INSTALL_DIR is not in PATH. You may need to add it to run 'usermgmt' directly."
+fi
+
+echo "Verifying installation..."
+if ! "$dst" --version; then
+  echo "Verification failed: installed binary did not run successfully." >&2
+  exit 7
+fi
+
+echo "usermgmt installed successfully from release ${TAG} -> ${dst}"
+