aria2 downloader (CivitAI)

downloader.sh

#!/usr/bin/env bash
set -euo pipefail

URL="${1:-}"
API_KEY="${2:-}"
OUT_DIR="${3:-.}"

if [ -z "$URL" ]; then
  echo "Usage: civitai-aria <download_url> [api_key] [output_dir]"
  exit 1
fi

# -----------------------------
# auto install aria2 if missing
# -----------------------------
need_bin() { command -v "$1" >/dev/null 2>&1; }

if ! need_bin aria2c; then
  echo "aria2c not found → installing..."
  if need_bin apt-get; then
    apt-get update -y
    apt-get install -y aria2 curl python3 ca-certificates
  elif need_bin apk; then
    apk add --no-cache aria2 curl python3 ca-certificates
  elif need_bin yum; then
    yum install -y aria2 curl python3 ca-certificates
  else
    echo "No supported package manager found. Install aria2 manually."
    exit 1
  fi
fi

mkdir -p "$OUT_DIR"

echo "Resolving filename..."

# Build curl args safely (no eval)
CURL_ARGS=(-sS -I -L)
if [ -n "$API_KEY" ]; then
  CURL_ARGS+=(-H "Authorization: Bearer $API_KEY")
fi
CURL_ARGS+=("$URL")

# Extract last Location header (redirect target)
LOCATION="$(
  curl "${CURL_ARGS[@]}" \
    | tr -d '\r' \
    | awk '/^location:/ {print $2}' \
    | tail -n 1
)"

# Extract filename from response-content-disposition inside redirect URL
FILENAME="$(
  printf "%s" "$LOCATION" \
  | sed -n 's/.*filename%3D%22\([^%]*\).*/\1/p' \
  | python3 -c 'import sys,urllib.parse; print(urllib.parse.unquote(sys.stdin.read().strip()))'
)"

if [ -z "$FILENAME" ]; then
  MODEL_ID="$(basename "${URL%/}")"
  FILENAME="civitai-${MODEL_ID}.bin"
fi

echo "Filename: $FILENAME"
echo "Downloading to: $OUT_DIR/$FILENAME"

DOWNLOAD_URL="$URL"
if [ -n "$API_KEY" ]; then
  # match your earlier working approach
  DOWNLOAD_URL="${URL}?token=${API_KEY}"
fi

aria2c \
  --allow-overwrite=true \
  --auto-file-renaming=false \
  --continue=true \
  --max-connection-per-server=16 \
  --split=16 \
  --min-split-size=1M \
  --file-allocation=none \
  --summary-interval=1 \
  "$DOWNLOAD_URL" \
  -d "$OUT_DIR" \
  -o "$FILENAME"

echo "Done."