app.py

import os, validators, logging
from flask import Flask, request, send_file
from flask_compress import Compress
from flask_cors import CORS
from dotenv import load_dotenv
from download import download_image
from main import main
from lib import create_dirs, is_debug
from recaptcha import verify_recaptcha_v3

load_dotenv()

logging.basicConfig(level=logging.INFO)

app = Flask(__name__)

allow_origins = [
  'https://playground.daiiz.dev',
  'https://pointillism.daiiz.dev'
]
if os.environ.get('DEV_MODE', '0') == '1':
  allow_origins.append('http://localhost:3000')
  app.logger.info('allow_origins: ' + ','.join(allow_origins))

CORS(app, resources={
  r"/api/generate": {"origins": allow_origins, "methods": ['POST', 'OPTIONS']}
})
app.config["COMPRESS_MIMETYPES"] = ["image/png"]
app.config["COMPRESS_ALGORITHM"] = ["gzip", "deflate"]
compress = Compress()
compress.init_app(app)

def parse_thumbnail_size(request):
  size_range = [100, 2000]
  size = 1000 # default size
  try:
    size = min(int(request.args.get("size", "1000")), size_range[1])
    if size < size_range[0]:
      size = size_range[0]
  except Exception as e:
    print(e)
  return size

def parse_histogram_equalization(request):
  auto = request.args.get("auto", "")
  if auto == '' or auto == 'no' or auto == '0':
    return False
  return True

def parse_output_format(request):
  png = request.args.get("png", "")
  if png == '' or png == 'no' or png == '0':
    return 'webp'
  return 'png'

def parse_binarization_threshold(request):
  threshold = request.args.get("bin", "")
  parsed_threshold = None
  try:
    parsed_threshold = int(threshold)
    parsed_threshold = max(0, min(parsed_threshold, 255))
  except:
    pass
  return parsed_threshold

def parse_base_image_mode(request):
  base_image = request.args.get('base', '')
  if base_image == 't':
    return 'Transparent'
  elif base_image == 'c1' or base_image == 'c':
    return 'Color1' # 白色(透明)箇所を塗りつぶす
  elif base_image == 'c0':
    return 'Color0'
  return 'White'

@app.route("/", methods=["GET"])
@app.route("/api/generate", methods=["POST"])
@compress.compressed()
def convert():
  # POSTリクエストの場合はreCAPTCHAの検証を行う
  # https://developers.google.com/recaptcha/docs/verify
  if request.method == 'POST':
    client_name = request.get_json().get('client', '')
    if client_name != 'playground':
      recaptchaToken = request.get_json().get('recaptchaToken', None)
      if not verify_recaptcha_v3(recaptchaToken):
        return 'Invalid request.\n', 400
    print("client_name:", client_name)

  is_data_uri = False
  image_url = request.args.get("url", "")
  if request.method == 'POST':
    image_data_uri = request.get_json().get('dataUri', None)
    if image_data_uri and image_data_uri.startswith('data:image/'):
      is_data_uri = True
      image_url = image_data_uri

  if not is_data_uri and not validators.url(image_url):
    return 'Invalid URL: %s\n' % image_url, 400
  size = parse_thumbnail_size(request)
  auto = parse_histogram_equalization(request)
  save_format = parse_output_format(request)
  threshold = parse_binarization_threshold(request)
  base_image_mode = parse_base_image_mode(request)

  # 画像をダウンロード
  input_file_name = ''
  try:
    input_file_name = download_image(image_url, is_data_uri)
  except Exception as e:
    return 'Invalid request: %s\n' % e, 400

  if not input_file_name:
    return 'Error: input_file_name is empty.\n', 500

  # 画像を点描画に変換
  output_file_path = ''
  try:
    print(size, auto)
    output_file_path = main(
      input_file_name,
      thumbnail_size=size,
      histogram_equalization=auto,
      save_format=save_format,
      binarization_threshold=threshold,
      base_image_mode=base_image_mode
    )
  except Exception as e:
    print(e)
    return 'Error: %s' % e, 500

  if output_file_path == '':
    return 'Error: output_file_path is empty.\n', 500

  return send_file(output_file_path, as_attachment=False, mimetype='image/' + save_format)

@app.route("/robots.txt")
def robots():
  return send_file('./public/robots.txt', as_attachment=False, mimetype='text/plain')

if __name__ == '__main__':
  create_dirs()
  app.run(host="0.0.0.0", port=8080, threaded=False, debug=is_debug())