install.sh

#!/usr/bin/env bash
# LiteLLM Installer
# Usage: curl -fsSL https://raw.githubusercontent.com/BerriAI/litellm/main/scripts/install.sh | sh
#
# NOTE: set -e without pipefail for POSIX sh compatibility (dash on Ubuntu/Debian
# ignores the shebang when invoked as `sh` and does not support `pipefail`).
set -eu

MIN_PYTHON_MAJOR=3
MIN_PYTHON_MINOR=9

# NOTE: before merging, this must stay as "litellm[proxy]" to install from PyPI.
LITELLM_PACKAGE="litellm[proxy]"

# ── colours ────────────────────────────────────────────────────────────────
if [ -t 1 ]; then
  BOLD='\033[1m'
  GREEN='\033[38;2;78;186;101m'
  GREY='\033[38;2;153;153;153m'
  YELLOW='\033[33m'
  RESET='\033[0m'
else
  BOLD='' GREEN='' GREY='' YELLOW='' RESET=''
fi

info()    { printf "${GREY}  %s${RESET}\n" "$*"; }
warn()    { printf "${YELLOW}  Warning: %s${RESET}\n" "$*" >&2; }
success() { printf "${GREEN}  ✔ %s${RESET}\n" "$*"; }
header()  { printf "${BOLD}  %s${RESET}\n" "$*"; }
die()     { printf "\n  Error: %s\n\n" "$*" >&2; exit 1; }

# ── banner ─────────────────────────────────────────────────────────────────
echo ""
cat << 'EOF'
  ██╗     ██╗████████╗███████╗██╗     ██╗     ███╗   ███╗
  ██║     ██║╚══██╔══╝██╔════╝██║     ██║     ████╗ ████║
  ██║     ██║   ██║   █████╗  ██║     ██║     ██╔████╔██║
  ██║     ██║   ██║   ██╔══╝  ██║     ██║     ██║╚██╔╝██║
  ███████╗██║   ██║   ███████╗███████╗███████╗██║ ╚═╝ ██║
  ╚══════╝╚═╝   ╚═╝   ╚══════╝╚══════╝╚══════╝╚═╝     ╚═╝
EOF
printf "  ${BOLD}LiteLLM Installer${RESET}  ${GREY}— unified gateway for 100+ LLM providers${RESET}\n\n"

# ── OS detection ───────────────────────────────────────────────────────────
OS="$(uname -s)"
ARCH="$(uname -m)"

case "$OS" in
  Darwin)  PLATFORM="macOS ($ARCH)" ;;
  Linux)   PLATFORM="Linux ($ARCH)" ;;
  *)       die "Unsupported OS: $OS. LiteLLM supports macOS and Linux." ;;
esac

info "Platform: $PLATFORM"

# ── Python detection ───────────────────────────────────────────────────────
PYTHON_BIN=""
for candidate in python3 python; do
  if command -v "$candidate" >/dev/null 2>&1; then
    major="$("$candidate" -c 'import sys; print(sys.version_info.major)' 2>/dev/null || true)"
    minor="$("$candidate" -c 'import sys; print(sys.version_info.minor)' 2>/dev/null || true)"
    if [ "${major:-0}" -ge "$MIN_PYTHON_MAJOR" ] && [ "${minor:-0}" -ge "$MIN_PYTHON_MINOR" ]; then
      PYTHON_BIN="$(command -v "$candidate")"
      info "Python: $("$candidate" --version 2>&1)"
      break
    fi
  fi
done

if [ -z "$PYTHON_BIN" ]; then
  die "Python ${MIN_PYTHON_MAJOR}.${MIN_PYTHON_MINOR}+ is required but not found.
  Install it from https://python.org/downloads or via your package manager:
    macOS:  brew install python@3
    Ubuntu: sudo apt install python3 python3-pip"
fi

# ── install ────────────────────────────────────────────────────────────────
# Prefer pipx or venv to avoid PEP 668 "externally-managed-environment" on
# Homebrew/ system Python.  Neither strategy requires system pip — pipx
# manages its own venvs and the venv strategy uses Python's built-in
# ensurepip, so there is no unconditional pip gate here.
echo ""
header "Installing litellm[proxy]…"
echo ""

LITELLM_BIN=""

# Strategy 1: pipx (best for CLI apps, per PEP 668)
# Try upgrade first to preserve existing flags (e.g. --include-deps); fall
# back to a fresh install if the package is not yet managed by pipx.
if command -v pipx >/dev/null 2>&1; then
  info "Using pipx (isolated install)"
  if pipx upgrade litellm 2>/dev/null; then
    # Ensure proxy extras are present (may be absent if originally installed
    # as bare "litellm" without [proxy]).  `pipx inject` has been available
    # since pipx 0.12.3 (~2019) and records injected deps in pipx metadata so
    # upgrades stay consistent; the `runpip` subcommand is newer (0.15.x) and would fail
    # on older pipx.
    if ! _inject_err="$(pipx inject litellm "${LITELLM_PACKAGE}" 2>&1)"; then
      warn "could not inject proxy extras (proxy features may fail until manually fixed)."
      printf '%s\n' "$_inject_err" >&2
    fi
    unset _inject_err 2>/dev/null || true
    _pipx_upgraded=1
  elif pipx install "${LITELLM_PACKAGE}"; then
    _pipx_upgraded=1
  fi
  if [ "${_pipx_upgraded:-0}" = "1" ]; then
    _pipx_bin_dir="${PIPX_BIN_DIR:-${HOME}/.local/bin}"
    _pipx_home="${PIPX_HOME:-${HOME}/.local/share/pipx}"
    for try in \
      "${_pipx_bin_dir}/litellm" \
      "${_pipx_home}/venvs/litellm/bin/litellm"; do
      if [ -n "$try" ] && [ -x "$try" ]; then
        LITELLM_BIN="$try"
        break
      fi
    done
    if [ -z "$LITELLM_BIN" ] && command -v litellm >/dev/null 2>&1; then
      LITELLM_BIN="$(command -v litellm)"
    fi
    if [ -z "$LITELLM_BIN" ]; then
      warn "pipx install/upgrade succeeded but the litellm binary was not found at expected locations (PIPX_BIN_DIR=${_pipx_bin_dir}, PIPX_HOME=${_pipx_home}) and not on PATH."
      warn "Falling back to a dedicated venv — you may still have a pipx-managed copy elsewhere; check: pipx list"
    fi
  else
    warn "pipx install failed (see above), falling back to venv"
  fi
fi

# Strategy 2: venv in ~/.litellm (avoids PEP 668 externally-managed-environment)
if [ -z "$LITELLM_BIN" ]; then
  LITELLM_VENV="${LITELLM_VENV:-${HOME}/.litellm/venv}"
  info "Using isolated venv: $LITELLM_VENV"
  mkdir -p "$(dirname "$LITELLM_VENV")"
  # Preserve an existing venv on repeat runs; use LITELLM_FORCE_VENV_RECREATE=1 to wipe it.
  if [ "${LITELLM_FORCE_VENV_RECREATE:-0}" = "1" ]; then
    "$PYTHON_BIN" -m venv --clear "$LITELLM_VENV" \
      || die "Failed to recreate venv. Try: $PYTHON_BIN -m venv --clear $LITELLM_VENV
On Ubuntu/Debian you may first need: sudo apt install python3-venv"
  elif [ ! -d "$LITELLM_VENV" ]; then
    "$PYTHON_BIN" -m venv "$LITELLM_VENV" \
      || die "Failed to create venv. Try: $PYTHON_BIN -m venv $LITELLM_VENV
On Ubuntu/Debian you may first need: sudo apt install python3-venv"
  elif [ ! -x "${LITELLM_VENV}/bin/python" ]; then
    info "Existing venv at ${LITELLM_VENV} is incomplete; recreating"
    "$PYTHON_BIN" -m venv --clear "$LITELLM_VENV" \
      || die "Failed to recreate venv. Try: $PYTHON_BIN -m venv --clear $LITELLM_VENV
On Ubuntu/Debian you may first need: sudo apt install python3-venv"
  fi
  "${LITELLM_VENV}/bin/pip" install -q --upgrade pip \
    || die "Failed to upgrade pip in venv. Try: ${LITELLM_VENV}/bin/pip install --upgrade pip"
  "${LITELLM_VENV}/bin/pip" install --upgrade "${LITELLM_PACKAGE}" \
    || die "pip install failed. Try manually: ${LITELLM_VENV}/bin/pip install '${LITELLM_PACKAGE}'"
  LITELLM_BIN="${LITELLM_VENV}/bin/litellm"
fi

if [ ! -x "$LITELLM_BIN" ]; then
  die "litellm binary not found. Try: pipx install '${LITELLM_PACKAGE}' or use a venv."
fi

# ── success banner ─────────────────────────────────────────────────────────
echo ""
success "LiteLLM installed"

installed_ver="$("$LITELLM_BIN" --version 2>&1 | grep -oE '[0-9]+\.[0-9]+\.[0-9]+' | head -1 || true)"
[ -n "$installed_ver" ] && info "Version: $installed_ver"

# ── PATH hint ──────────────────────────────────────────────────────────────
if ! command -v litellm >/dev/null 2>&1; then
  LITELLM_DIR="$(dirname "$LITELLM_BIN")"
  info "Note: add litellm to your PATH:  export PATH=\"\$PATH:${LITELLM_DIR}\""
fi

# ── launch setup wizard ────────────────────────────────────────────────────
echo ""
printf "  ${BOLD}Run the interactive setup wizard?${RESET} ${GREY}(Y/n)${RESET}: "
# /dev/tty may be unavailable in Docker/CI — default to yes if it can't be read
answer=""
if [ -r /dev/tty ]; then
  read -r answer </dev/tty || answer=""
fi

if [ -z "$answer" ] || [ "$answer" = "y" ] || [ "$answer" = "Y" ]; then
  echo ""
  # Use /dev/tty for interactive input when available (stdin is a pipe from curl)
  if [ -r /dev/tty ]; then
    exec "$LITELLM_BIN" --setup </dev/tty
  else
    exec "$LITELLM_BIN" --setup
  fi
else
  echo ""
  header "Quick start:"
  echo ""
  info "  litellm --setup          # interactive wizard"
  info "  litellm --model gpt-4o   # single-model quickstart"
  echo ""
  info "Docs: https://docs.litellm.ai"
  echo ""
fi