From: Christian Heller Date: Sun, 24 Sep 2023 03:15:31 +0000 (+0200) Subject: Bookmaker: add some basic input validation. X-Git-Url: https://plomlompom.com/repos/%7B%7B%20web_path%20%7D%7D/decks/%7B%7Bdb.prefix%7D%7D/static/blog?a=commitdiff_plain;h=877731d064ed31edb8e343b98b6fd91fab12dee9;p=misc Bookmaker: add some basic input validation. --- diff --git a/bookmaker.py b/bookmaker.py index a82f986..48d4af2 100755 --- a/bookmaker.py +++ b/bookmaker.py @@ -2,6 +2,7 @@ import pypdf import argparse import io +import os from reportlab.lib.pagesizes import A4 a4_width, a4_height = A4 points_per_cm = 10 * 72 / 25.4 @@ -78,9 +79,70 @@ parser.add_argument("-s", "--symmetry", action="store_true", help="alternate hor parser.add_argument("-n", "--nup4", action='store_true', help="puts 4 input pages onto 1 output page, adds binding cut stencil") parser.add_argument("-a", "--analyze", action="store_true", help="in --nup4, print lines identifying spine, page borders") parser.add_argument("-m", "--print_margin", type=float, default=0.43, help="print margin for --nup4 in cm (default 0.43)") -parser.add_argument("-H", "--long_help", action="store_true", help="show examples, explanations, additional usage notes") args = parser.parse_args() +# some basic input validation +for filename in args.input_file: + if not os.path.isfile(filename): + raise ValueError("-i: %s is not a file" % filename) + try: + with open(filename, 'rb') as file: + pypdf.PdfReader(file) + except pypdf.errors.PdfStreamError: + raise ValueError("-i: cannot interpret %s as PDF file" % filename) +def validate_page_range(p_string, err_msg_prefix): + err_msg = "%s: invalid page range string: %s" % (err_msg_prefix, p_string) + if '-' not in p_string: + raise ValueError(err_msg) + tokens = p_string.split("-") + if len(tokens) > 2: + raise ValueError(err_msg) + for i, token in enumerate(tokens): + if token == "": + continue + if i == 0 and token == "start": + continue + if i == 1 and token == "end": + continue + try: + int(token) + except: + raise ValueError(err_msg) +if args.page_range: + for p_string in args.page_range: + validate_page_range(p_string, "-p") + if len(args.page_range) > len(args.input_file): + raise ValueError("more -p arguments than -i arguments") +if args.crops: + for c_string in args.crops: + initial_split = c_string.split(':') + if len(initial_split) > 2: + raise ValueError("-c: cropping string has multiple ':': %s" % c_string) + if len(initial_split) > 1: + validate_page_range(initial_split[0], "-c") + crops = initial_split[1].split(",") + + else: + crops = initial_split[0].split(",") + if len(crops) != 4: + raise ValueError("-c: cropping should contain three ',': %s" % c_string) + for crop in crops: + try: + float(crop) + except: + raise ValueError("-c: non-number crop in %s" % c_string) +if args.rotate_page: + for r in arg.rotate_page: + try: + int(r) + except: + raise ValueError("-r: non-integer value: %s" % r) +try: + float(args.print_margin) +except: + raise ValueError("-m: non-float value: %s" % arg.print_margin) + + # select pages from input files def parse_page_range(range_string, pages): start_page = 0 @@ -141,41 +203,41 @@ for page in pages_to_add: crops_at_page = [(0,0,0,0)]*len(pages_to_add) zoom_at_page = [1]*len(pages_to_add) if args.crops: - for crops in args.crops: - initial_split = crops.split(':') - if len(initial_split) > 1: - page_range = initial_split[0] - crops = initial_split[1] - else: - page_range = None - crops = initial_split[0] - start_page, end_page = parse_page_range(page_range, pages_to_add) - crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm = [float(x) for x in crops.split(',')] - crop_left = crop_left_cm * points_per_cm - crop_bottom = crop_bottom_cm * points_per_cm - crop_right = crop_right_cm * points_per_cm - crop_top = crop_top_cm * points_per_cm - if args.symmetry: - print("-c, -t: to pages %d to %d applying crops: left %.2fcm, bottom %.2fcm, right %.2fcm, top %.2fcm (but alternating left and right crop between even and odd pages)" % (start_page + 1, end_page, crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm)) - else: - print("-c: to pages %d to %d applying crops: left %.2fcm, bottom %.2fcm, right %.2fcm, top %.2fcm" % (start_page + 1, end_page, crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm)) - cropped_width = a4_width - crop_left - crop_right - cropped_height = a4_height - crop_bottom - crop_top - zoom = 1 - zoom_horizontal = a4_width / (a4_width - crop_left - crop_right) - zoom_vertical = a4_height / (a4_height - crop_bottom - crop_top) - if (zoom_horizontal > 1 and zoom_vertical < 1) or (zoom_horizontal < 1 and zoom_vertical > 1): - raise ValueError("crops would create opposing zoom directions") - elif zoom_horizontal + zoom_vertical > 2: - zoom = min(zoom_horizontal, zoom_vertical) - else: - zoom = max(zoom_horizontal, zoom_vertical) - for page_num in range(start_page, end_page): - if args.symmetry and page_num % 2: - crops_at_page[page_num] = (crop_right, crop_bottom, crop_left, crop_top) - else: - crops_at_page[page_num] = (crop_left, crop_bottom, crop_right, crop_top) - zoom_at_page[page_num] = zoom + for crops in args.crops: + initial_split = crops.split(':') + if len(initial_split) > 1: + page_range = initial_split[0] + crops = initial_split[1] + else: + page_range = None + crops = initial_split[0] + start_page, end_page = parse_page_range(page_range, pages_to_add) + crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm = [float(x) for x in crops.split(',')] + crop_left = crop_left_cm * points_per_cm + crop_bottom = crop_bottom_cm * points_per_cm + crop_right = crop_right_cm * points_per_cm + crop_top = crop_top_cm * points_per_cm + if args.symmetry: + print("-c, -t: to pages %d to %d applying crops: left %.2fcm, bottom %.2fcm, right %.2fcm, top %.2fcm (but alternating left and right crop between even and odd pages)" % (start_page + 1, end_page, crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm)) + else: + print("-c: to pages %d to %d applying crops: left %.2fcm, bottom %.2fcm, right %.2fcm, top %.2fcm" % (start_page + 1, end_page, crop_left_cm, crop_bottom_cm, crop_right_cm, crop_top_cm)) + cropped_width = a4_width - crop_left - crop_right + cropped_height = a4_height - crop_bottom - crop_top + zoom = 1 + zoom_horizontal = a4_width / (a4_width - crop_left - crop_right) + zoom_vertical = a4_height / (a4_height - crop_bottom - crop_top) + if (zoom_horizontal > 1 and zoom_vertical < 1) or (zoom_horizontal < 1 and zoom_vertical > 1): + raise ValueError("crops would create opposing zoom directions") + elif zoom_horizontal + zoom_vertical > 2: + zoom = min(zoom_horizontal, zoom_vertical) + else: + zoom = max(zoom_horizontal, zoom_vertical) + for page_num in range(start_page, end_page): + if args.symmetry and page_num % 2: + crops_at_page[page_num] = (crop_right, crop_bottom, crop_left, crop_top) + else: + crops_at_page[page_num] = (crop_left, crop_bottom, crop_right, crop_top) + zoom_at_page[page_num] = zoom writer = pypdf.PdfWriter() if not args.nup4: