Reimplementation (#1)

* refactor into separate modules

* update README

udib.py

@@ -0,0 +1,162 @@
+#!/usr/bin/env python3
+"""Main entry point for the interactive udib CLI tool."""
+
+from pathlib import Path
+from sys import exit
+from tempfile import TemporaryDirectory
+
+from cli.clibella import Printer
+from cli.parser import get_argument_parser
+from core.utils import download_and_verify_debian_iso
+from iso.injection import inject_preseed_file_into_iso
+from net.download import download_file
+from net.scrape import get_debian_preseed_file_urls, get_debian_iso_urls
+
+
+def main():
+
+    # create a CLI printer
+    p = Printer()
+
+    # create an argument parser and read arguments
+    parser = get_argument_parser()
+    args = parser.parse_args()
+
+    # parse and verify output file if sepcified
+    if args.path_to_output_file:
+        path_to_output_file = Path(args.path_to_output_file)
+        if "~" in str(path_to_output_file):
+            path_to_output_file = path_to_output_file.expanduser()
+        path_to_output_file = path_to_output_file.resolve()
+
+        if path_to_output_file.exists():
+            p.error(f"Output file already exists: '{path_to_output_file}'.")
+            exit(1)
+    else:
+        path_to_output_file = None
+
+    # parse and verify output dir if sepcified
+    if args.path_to_output_dir:
+        path_to_output_dir = Path(args.path_to_output_dir)
+        if "~" in str(path_to_output_dir):
+            path_to_output_dir = path_to_output_dir.expanduser()
+        path_to_output_dir = path_to_output_dir.resolve()
+
+        if not path_to_output_dir.is_dir():
+            p.error(f"No such directory: '{path_to_output_dir}'.")
+            exit(1)
+    else:
+        path_to_output_dir = None
+
+    if args.subparser_name == "get":
+        if args.WHAT == "preseed-file-basic":
+            # download the basic example preseedfile
+
+            if not path_to_output_file:
+                output_file_name = get_debian_preseed_file_urls()["basic"]["name"]
+                if path_to_output_dir:
+                    path_to_output_file = path_to_output_dir / output_file_name
+                else:
+                    path_to_output_file = Path.cwd() / output_file_name
+
+            p.info("Retrieving basic preseed example file...")
+            download_file(
+                path_to_output_file,
+                get_debian_preseed_file_urls()["basic"]["url"],
+                show_progress=False,
+                printer=p,
+            )
+            p.success(
+                f"Basic preseed example file was saved to '{path_to_output_file}'."
+            )
+            exit(0)
+
+        elif args.WHAT == "preseed-file-full":
+            # download the full example preseedfile
+
+            if not path_to_output_file:
+                output_file_name = get_debian_preseed_file_urls()["full"]["name"]
+                if path_to_output_dir:
+                    path_to_output_file = path_to_output_dir / output_file_name
+                else:
+                    path_to_output_file = Path.cwd() / output_file_name
+
+            p.info("Retrieving full preseed example file...")
+            download_file(
+                path_to_output_file,
+                get_debian_preseed_file_urls()["full"]["url"],
+                show_progress=False,
+                printer=p,
+            )
+            p.success(
+                f"Full preseed example file was saved to '{path_to_output_file}'."
+            )
+            exit(0)
+
+        elif args.WHAT == "iso":
+            # download and verify installation image
+            p.info("Downloading latest Debian stable x86-64 netinst ISO...")
+
+            if not path_to_output_file:
+                output_file_name = get_debian_iso_urls()["image_file"]["name"]
+                if path_to_output_dir:
+                    path_to_output_file = path_to_output_dir / output_file_name
+                else:
+                    path_to_output_file = Path.cwd() / output_file_name
+
+            download_and_verify_debian_iso(path_to_output_file, printer=p)
+            p.success(f"Debian ISO saved to '{path_to_output_file}'.")
+            exit(0)
+
+    elif args.subparser_name == "inject":
+        image_file_name = Path(get_debian_iso_urls()["image_file"]["name"])
+        if not path_to_output_file:
+            output_file_name = image_file_name.stem + "-preseeded" + image_file_name.suffix
+            if path_to_output_dir:
+                path_to_output_file = path_to_output_dir / output_file_name
+            else:
+                path_to_output_file = Path.cwd() / output_file_name
+
+        # verify preseed file path
+        path_to_preseed_file = Path(args.PRESEEDFILE)
+        if "~" in str(path_to_preseed_file):
+            path_to_preseed_file = Path(path_to_preseed_file).expanduser()
+        path_to_preseed_file = Path(path_to_preseed_file).resolve()
+        if not path_to_preseed_file.is_file():
+            p.error(f"No such file: '{path_to_preseed_file}'.")
+            exit(1)
+
+        # verify image file path if set by user or download fresh iso if unset
+        temp_iso_dir = None
+        if args.path_to_image_file:
+            path_to_image_file = Path(args.path_to_image_file)
+            if "~" in str(path_to_image_file):
+                path_to_image_file = Path(path_to_image_file).expanduser()
+            path_to_image_file = Path(path_to_image_file).resolve()
+            if not path_to_image_file.is_file():
+                p.error(f"No such file: '{path_to_image_file}'.")
+                exit(1)
+        else:
+            # download a Debian ISO to a temporary directory
+            p.info("Downloading the latest Debian x86-64 netinst image...")
+            temp_iso_dir = TemporaryDirectory()
+            path_to_iso_dir = Path(temp_iso_dir.name)
+            path_to_image_file = path_to_iso_dir/image_file_name
+            download_and_verify_debian_iso(path_to_image_file, printer=p)
+
+        # inject the preseed file
+        inject_preseed_file_into_iso(
+            path_to_output_file,
+            path_to_image_file,
+            path_to_preseed_file,
+            printer=p,
+        )
+
+        # clear out temporary directory if one was created earlier
+        if temp_iso_dir:
+            temp_iso_dir.cleanup()
+
+        exit(0)
+
+if __name__ == '__main__':
+    main()