Bump version to 3.8.0

Update minimum Python version to 3.11
Support ILIAS 9
2025-07-12 14:12:30 +02:00 · 2025-04-15 11:32:22 +02:00 · 2025-04-15 11:31:39 +02:00 · 2025-04-15 11:19:53 +02:00 · 2025-03-09 23:44:25 +01:00 · 2025-02-19 16:23:20 +01:00
38 changed files with 3425 additions and 2402 deletions
--- a/.github/dependabot.yml
+++ b/.github/dependabot.yml
@ -0,0 +1,10 @@
+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: monthly
+    groups:
+      gh-actions:
+        patterns:
+          - "*"
--- a/.github/workflows/build-and-release.yml
+++ b/.github/workflows/build-and-release.yml
@ -1,6 +1,6 @@
 name: build-and-release

-on: push
+on: [push, pull_request]

 defaults:
  run:
@ -13,13 +13,12 @@ jobs:
    strategy:
      fail-fast: false
      matrix:
-        os: [ubuntu-latest, windows-latest, macos-latest]
-        python: ["3.9"]
+        os: [ubuntu-latest, windows-latest, macos-13, macos-latest]
+        python: ["3.11"]
    steps:
+      - uses: actions/checkout@v4

-      - uses: actions/checkout@v3
-
-      - uses: actions/setup-python@v4
+      - uses: actions/setup-python@v5
        with:
          python-version: ${{ matrix.python }}

@ -34,7 +33,12 @@ jobs:
        run: ./scripts/setup --no-pip

      - name: Run checks
-        run: ./scripts/check
+        run: |
+          ./scripts/check
+          ./scripts/format
+
+      - name: Assert no changes
+        run: git diff --exit-code

      - name: Build
        run: ./scripts/build
@ -45,9 +49,9 @@ jobs:
        run: mv dist/pferd* dist/pferd-${{ matrix.os }}

      - name: Upload binary
-        uses: actions/upload-artifact@v3
+        uses: actions/upload-artifact@v4
        with:
-          name: Binaries
+          name: pferd-${{ matrix.os }}
          path: dist/pferd-${{ matrix.os }}

  release:
@ -57,18 +61,20 @@ jobs:
    steps:

      - name: Download binaries
-        uses: actions/download-artifact@v3
+        uses: actions/download-artifact@v4
        with:
-          name: Binaries
+          pattern: pferd-*
+          merge-multiple: true

      - name: Rename binaries
        run: |
          mv pferd-ubuntu-latest pferd-linux
          mv pferd-windows-latest pferd-windows.exe
+          mv pferd-macos-13 pferd-mac-x86_64
          mv pferd-macos-latest pferd-mac

      - name: Create release
-        uses: softprops/action-gh-release@v1
+        uses: softprops/action-gh-release@v2
        env:
          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        with:
@ -76,3 +82,4 @@ jobs:
            pferd-linux
            pferd-windows.exe
            pferd-mac
+            pferd-mac-x86_64
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@ -22,6 +22,54 @@ ambiguous situations.

 ## Unreleased

+## 3.8.0 - 2025-04-15
+
+### Added
+- Support for ILIAS 9
+
+### Changed
+- Added prettier CSS to forum threads
+- Increase minimum supported Python version to 3.11
+
+## Fixed
+- File links in report on Windows
+- TOTP authentication in KIT Shibboleth
+- Forum crawling only considering the first 20 entries
+
+## 3.7.0 - 2024-11-13
+
+### Added
+- Support for MOB videos in page descriptions
+- Clickable links in the report to directly open new/modified/not-deleted files
+- Support for non KIT shibboleth login
+
+### Changed
+- Remove videos from description pages
+- Perform ILIAS cycle detection after processing the transform to allow
+  ignoring duplicated elements
+- Parse headings (h1-h3) as folders in kit-ipd crawler
+
+### Fixed
+- Personal desktop/dashboard/favorites crawling
+- Crawling of nested courses
+- Downloading of links with no target URL
+- Handle row flex on description pages
+- Add `<!DOCTYPE html>` heading to forum threads to fix mime type detection
+- Handle groups in cards
+
+## 3.6.0 - 2024-10-23
+
+### Added
+- Generic `ilias-web` crawler and `ilias-web` CLI command
+- Support for the course overview page. Using this URL as a target might cause
+  duplication warnings, as subgroups are listed separately.
+- Support for named capture groups in regex transforms
+- Crawl custom item groups as folders
+
+### Fixed
+- Normalization of meeting names in cards
+- Sanitization of slashes in exercise container names
+
 ## 3.5.2 - 2024-04-14

 ### Fixed
--- a/CONFIG.md
+++ b/CONFIG.md
@ -4,11 +4,11 @@ A config file consists of sections. A section begins with a `[section]` header,
 which is followed by a list of `key = value` pairs. Comments must be on their
 own line and start with `#`. Multiline values must be indented beyond their key.
 Boolean values can be `yes` or `no`. For more details and some examples on the
-format, see the [configparser documentation][1] ([interpolation][2] is
-disabled).
+format, see the [configparser documentation][cp-file]
+([interpolation][cp-interp] is disabled).

-[1]: <https://docs.python.org/3/library/configparser.html#supported-ini-file-structure> "Supported INI File Structure"
-[2]: <https://docs.python.org/3/library/configparser.html#interpolation-of-values> "Interpolation of values"
+[cp-file]: <https://docs.python.org/3/library/configparser.html#supported-ini-file-structure> "Supported INI File Structure"
+[cp-interp]: <https://docs.python.org/3/library/configparser.html#interpolation-of-values> "Interpolation of values"

 ## The `DEFAULT` section

@ -146,7 +146,7 @@ crawler simulate a slower, network-based crawler.

 This crawler crawls a KIT-IPD page by url. The root page can be crawled from
 outside the KIT network so you will be informed about any new/deleted files,
-but downloading files requires you to be within. Adding a show delay between
+but downloading files requires you to be within. Adding a short delay between
 requests is likely a good idea.

 - `target`: URL to a KIT-IPD page
@ -154,6 +154,63 @@ requests is likely a good idea.
  matches, the given link is downloaded as a file. This is used to extract
  files from KIT-IPD pages. (Default: `^.*?[^/]+\.(pdf|zip|c|cpp|java)$`)

+### The `ilias-web` crawler
+
+This crawler crawls a generic ILIAS instance.
+
+Inspired by [this ILIAS downloader][ilias-dl], the following configurations should work
+out of the box for the corresponding universities:
+
+[ilias-dl]: https://github.com/V3lop5/ilias-downloader/blob/main/configs "ilias-downloader configs"
+
+| University    | `base_url`                              | `login_type` | `client_id`   |
+|---------------|-----------------------------------------|--------------|---------------|
+| FH Aachen     | https://www.ili.fh-aachen.de            | local        | elearning     |
+| Uni Köln      | https://www.ilias.uni-koeln.de/ilias    | local        | uk            |
+| Uni Konstanz  | https://ilias.uni-konstanz.de           | local        | ILIASKONSTANZ |
+| Uni Stuttgart | https://ilias3.uni-stuttgart.de         | local        | Uni_Stuttgart |
+| Uni Tübingen  | https://ovidius.uni-tuebingen.de/ilias3 | shibboleth   |               |
+
+If your university isn't listed, try navigating to your instance's login page.
+Assuming no custom login service is used, the URL will look something like this:
+
+```jinja
+{{ base_url }}/login.php?client_id={{ client_id }}&cmd=force_login&lang=
+```
+
+If the values work, feel free to submit a PR and add them to the table above.
+
+- `base_url`: The URL where the ILIAS instance is located. (Required)
+- `login_type`: How you authenticate. (Required)
+    - `local`: Use `client_id` for authentication.
+    - `shibboleth`: Use shibboleth for authentication.
+- `client_id`: An ID used for authentication if `login_type` is `local`. Is
+  ignored if `login_type` is `shibboleth`.
+- `target`: The ILIAS element to crawl. (Required)
+    - `desktop`: Crawl your personal desktop / dashboard
+    - `<course id>`: Crawl the course with the given id
+    - `<url>`: Crawl a given element by URL (preferably the permanent URL linked
+      at the bottom of its ILIAS page).  
+      This also supports the "My Courses" overview page to download *all*
+      courses. Note that this might produce confusing local directory layouts
+      and duplication warnings if you are a member of an ILIAS group. The
+      `desktop` target is generally preferable.
+- `auth`: Name of auth section to use for login. (Required)
+- `tfa_auth`: Name of auth section to use for two-factor authentication. Only
+  uses the auth section's password. (Default: Anonymous `tfa` authenticator)
+- `links`: How to represent external links. (Default: `fancy`)
+    - `ignore`: Don't download links.
+    - `plaintext`: A text file containing only the URL.
+    - `fancy`: A HTML file looking like the ILIAS link element.
+    - `internet-shortcut`: An internet shortcut file (`.url` file).
+- `link_redirect_delay`: Time (in seconds) until `fancy` link files will
+  redirect to the actual URL. Set to a negative value to disable the automatic
+  redirect. (Default: `-1`)
+- `videos`: Whether to download videos. (Default: `no`)
+- `forums`: Whether to download forum threads. (Default: `no`)
+- `http_timeout`: The timeout (in seconds) for all HTTP requests. (Default:
+  `20.0`)
+
 ### The `kit-ilias-web` crawler

 This crawler crawls the KIT ILIAS instance.
@ -232,10 +289,10 @@ is stored in the keyring.

 ### The `pass` authenticator

-This authenticator queries the [`pass` password manager][3] for a username and
-password. It tries to be mostly compatible with [browserpass][4] and
-[passff][5], so see those links for an overview of the format. If PFERD fails
-to load your password, you can use the `--explain` flag to see why.
+This authenticator queries the [`pass` password manager][pass] for a username
+and password. It tries to be mostly compatible with [browserpass][browserpass]
+and [passff][passff], so see those links for an overview of the format. If PFERD
+fails to load your password, you can use the `--explain` flag to see why.

 - `passname`: The name of the password to use (Required)
 - `username_prefixes`: A comma-separated list of username line prefixes
@ -243,9 +300,9 @@ to load your password, you can use the `--explain` flag to see why.
 - `password_prefixes`: A comma-separated list of password line prefixes
  (Default: `password,pass,secret`)

-[3]: <https://www.passwordstore.org/> "Pass: The Standard Unix Password Manager"
-[4]: <https://github.com/browserpass/browserpass-extension#organizing-password-store> "Organizing password store"
-[5]: <https://github.com/passff/passff#multi-line-format> "Multi-line format"
+[pass]: <https://www.passwordstore.org/> "Pass: The Standard Unix Password Manager"
+[browserpass]: <https://github.com/browserpass/browserpass-extension#organizing-password-store> "Organizing password store"
+[passff]: <https://github.com/passff/passff#multi-line-format> "Multi-line format"

 ### The `tfa` authenticator

@ -344,7 +401,8 @@ matches `SOURCE`, the output path is created using `TARGET` as template.
 be referred to as `{g<n>}` (e.g. `{g3}`). `{g0}` refers to the original path.
 If capturing group *n*'s contents are a valid integer, the integer value is
 available as `{i<n>}` (e.g. `{i3}`). If capturing group *n*'s contents are a
-valid float, the float value is available as `{f<n>}` (e.g. `{f3}`). If a
+valid float, the float value is available as `{f<n>}` (e.g. `{f3}`). Named capture
+groups (e.g. `(?P<name>)`) are available by their name (e.g. `{name}`). If a
 capturing group is not present (e.g. when matching the string `cd` with the
 regex `(ab)?cd`), the corresponding variables are not defined.

--- a/4
+++ b/4
@ -1,6 +1,6 @@
-Copyright 2019-2021 Garmelon, I-Al-Istannen, danstooamerican, pavelzw,
+Copyright 2019-2024 Garmelon, I-Al-Istannen, danstooamerican, pavelzw,
                    TheChristophe, Scriptim, thelukasprobst, Toorero,
-                    Mr-Pine
+                    Mr-Pine, p-fruck, PinieP

 Permission is hereby granted, free of charge, to any person obtaining a copy of
 this software and associated documentation files (the "Software"), to deal in
--- a/PFERD/auth/keyring.py
+++ b/PFERD/auth/keyring.py
@ -1,4 +1,4 @@
-from typing import Optional, Tuple
+from typing import Optional, Tuple, cast

 import keyring

@ -13,7 +13,7 @@ class KeyringAuthSection(AuthSection):
        return self.s.get("username")

    def keyring_name(self) -> str:
-        return self.s.get("keyring_name", fallback=NAME)
+        return cast(str, self.s.get("keyring_name", fallback=NAME))


 class KeyringAuthenticator(Authenticator):
--- a/PFERD/cli/init.py
+++ b/PFERD/cli/init.py
@ -8,6 +8,7 @@
 # well.

 from . import command_local  # noqa: F401 imported but unused
+from . import command_ilias_web  # noqa: F401 imported but unused
 from . import command_kit_ilias_web  # noqa: F401 imported but unused
 from . import command_kit_ipd  # noqa: F401 imported but unused
 from .parser import PARSER, ParserLoadError, load_default_section  # noqa: F401 imported but unused
--- a/PFERD/cli/command_ilias_web.py
+++ b/PFERD/cli/command_ilias_web.py
@ -0,0 +1,56 @@
+import argparse
+import configparser
+
+from ..logging import log
+from .common_ilias_args import configure_common_group_args, load_common
+from .parser import CRAWLER_PARSER, SUBPARSERS, load_crawler
+
+COMMAND_NAME = "ilias-web"
+
+SUBPARSER = SUBPARSERS.add_parser(
+    COMMAND_NAME,
+    parents=[CRAWLER_PARSER],
+)
+
+GROUP = SUBPARSER.add_argument_group(
+    title=f"{COMMAND_NAME} crawler arguments",
+    description=f"arguments for the '{COMMAND_NAME}' crawler",
+)
+
+GROUP.add_argument(
+    "--base-url",
+    type=str,
+    metavar="BASE_URL",
+    help="The base url of the ilias instance"
+)
+
+GROUP.add_argument(
+    "--client-id",
+    type=str,
+    metavar="CLIENT_ID",
+    help="The client id of the ilias instance"
+)
+
+configure_common_group_args(GROUP)
+
+
+def load(
+        args: argparse.Namespace,
+        parser: configparser.ConfigParser,
+) -> None:
+    log.explain(f"Creating config for command '{COMMAND_NAME}'")
+
+    parser["crawl:ilias"] = {}
+    section = parser["crawl:ilias"]
+    load_crawler(args, section)
+
+    section["type"] = COMMAND_NAME
+    if args.ilias_url is not None:
+        section["base_url"] = args.ilias_url
+    if args.client_id is not None:
+        section["client_id"] = args.client_id
+
+    load_common(section, args, parser)
+
+
+SUBPARSER.set_defaults(command=load)
--- a/PFERD/cli/command_kit_ilias_web.py
+++ b/PFERD/cli/command_kit_ilias_web.py
@ -1,120 +1,37 @@
 import argparse
 import configparser
-from pathlib import Path

-from ..crawl.ilias.file_templates import Links
 from ..logging import log
-from .parser import (CRAWLER_PARSER, SUBPARSERS, BooleanOptionalAction, ParserLoadError, load_crawler,
-                     show_value_error)
+from .common_ilias_args import configure_common_group_args, load_common
+from .parser import CRAWLER_PARSER, SUBPARSERS, load_crawler
+
+COMMAND_NAME = "kit-ilias-web"

 SUBPARSER = SUBPARSERS.add_parser(
-    "kit-ilias-web",
+    COMMAND_NAME,
    parents=[CRAWLER_PARSER],
 )

 GROUP = SUBPARSER.add_argument_group(
-    title="kit-ilias-web crawler arguments",
-    description="arguments for the 'kit-ilias-web' crawler",
-)
-GROUP.add_argument(
-    "target",
-    type=str,
-    metavar="TARGET",
-    help="course id, 'desktop', or ILIAS URL to crawl"
-)
-GROUP.add_argument(
-    "output",
-    type=Path,
-    metavar="OUTPUT",
-    help="output directory"
-)
-GROUP.add_argument(
-    "--username", "-u",
-    type=str,
-    metavar="USERNAME",
-    help="user name for authentication"
-)
-GROUP.add_argument(
-    "--keyring",
-    action=BooleanOptionalAction,
-    help="use the system keyring to store and retrieve passwords"
-)
-GROUP.add_argument(
-    "--credential-file",
-    type=Path,
-    metavar="PATH",
-    help="read username and password from a credential file"
-)
-GROUP.add_argument(
-    "--links",
-    type=show_value_error(Links.from_string),
-    metavar="OPTION",
-    help="how to represent external links"
-)
-GROUP.add_argument(
-    "--link-redirect-delay",
-    type=int,
-    metavar="SECONDS",
-    help="time before 'fancy' links redirect to to their target (-1 to disable)"
-)
-GROUP.add_argument(
-    "--videos",
-    action=BooleanOptionalAction,
-    help="crawl and download videos"
-)
-GROUP.add_argument(
-    "--forums",
-    action=BooleanOptionalAction,
-    help="crawl and download forum posts"
-)
-GROUP.add_argument(
-    "--http-timeout", "-t",
-    type=float,
-    metavar="SECONDS",
-    help="timeout for all HTTP requests"
+    title=f"{COMMAND_NAME} crawler arguments",
+    description=f"arguments for the '{COMMAND_NAME}' crawler",
 )

+configure_common_group_args(GROUP)
+

 def load(
        args: argparse.Namespace,
        parser: configparser.ConfigParser,
 ) -> None:
-    log.explain("Creating config for command 'kit-ilias-web'")
+    log.explain(f"Creating config for command '{COMMAND_NAME}'")

    parser["crawl:ilias"] = {}
    section = parser["crawl:ilias"]
    load_crawler(args, section)

-    section["type"] = "kit-ilias-web"
-    section["target"] = str(args.target)
-    section["output_dir"] = str(args.output)
-    section["auth"] = "auth:ilias"
-    if args.links is not None:
-        section["links"] = str(args.links.value)
-    if args.link_redirect_delay is not None:
-        section["link_redirect_delay"] = str(args.link_redirect_delay)
-    if args.videos is not None:
-        section["videos"] = "yes" if args.videos else "no"
-    if args.forums is not None:
-        section["forums"] = "yes" if args.forums else "no"
-    if args.http_timeout is not None:
-        section["http_timeout"] = str(args.http_timeout)
-
-    parser["auth:ilias"] = {}
-    auth_section = parser["auth:ilias"]
-    if args.credential_file is not None:
-        if args.username is not None:
-            raise ParserLoadError("--credential-file and --username can't be used together")
-        if args.keyring:
-            raise ParserLoadError("--credential-file and --keyring can't be used together")
-        auth_section["type"] = "credential-file"
-        auth_section["path"] = str(args.credential_file)
-    elif args.keyring:
-        auth_section["type"] = "keyring"
-    else:
-        auth_section["type"] = "simple"
-    if args.username is not None:
-        auth_section["username"] = args.username
+    section["type"] = COMMAND_NAME
+    load_common(section, args, parser)


 SUBPARSER.set_defaults(command=load)
--- a/PFERD/cli/common_ilias_args.py
+++ b/PFERD/cli/common_ilias_args.py
@ -0,0 +1,104 @@
+import argparse
+import configparser
+from pathlib import Path
+
+from ..crawl.ilias.file_templates import Links
+from .parser import BooleanOptionalAction, ParserLoadError, show_value_error
+
+
+def configure_common_group_args(group: argparse._ArgumentGroup) -> None:
+    """These arguments are shared between the KIT and generic Ilias web command."""
+    group.add_argument(
+        "target",
+        type=str,
+        metavar="TARGET",
+        help="course id, 'desktop', or ILIAS URL to crawl"
+    )
+    group.add_argument(
+        "output",
+        type=Path,
+        metavar="OUTPUT",
+        help="output directory"
+    )
+    group.add_argument(
+        "--username", "-u",
+        type=str,
+        metavar="USERNAME",
+        help="user name for authentication"
+    )
+    group.add_argument(
+        "--keyring",
+        action=BooleanOptionalAction,
+        help="use the system keyring to store and retrieve passwords"
+    )
+    group.add_argument(
+        "--credential-file",
+        type=Path,
+        metavar="PATH",
+        help="read username and password from a credential file"
+    )
+    group.add_argument(
+        "--links",
+        type=show_value_error(Links.from_string),
+        metavar="OPTION",
+        help="how to represent external links"
+    )
+    group.add_argument(
+        "--link-redirect-delay",
+        type=int,
+        metavar="SECONDS",
+        help="time before 'fancy' links redirect to to their target (-1 to disable)"
+    )
+    group.add_argument(
+        "--videos",
+        action=BooleanOptionalAction,
+        help="crawl and download videos"
+    )
+    group.add_argument(
+        "--forums",
+        action=BooleanOptionalAction,
+        help="crawl and download forum posts"
+    )
+    group.add_argument(
+        "--http-timeout", "-t",
+        type=float,
+        metavar="SECONDS",
+        help="timeout for all HTTP requests"
+    )
+
+
+def load_common(
+    section: configparser.SectionProxy,
+    args: argparse.Namespace,
+    parser: configparser.ConfigParser,
+) -> None:
+    """Load common config between generic and KIT ilias web command"""
+    section["target"] = str(args.target)
+    section["output_dir"] = str(args.output)
+    section["auth"] = "auth:ilias"
+    if args.links is not None:
+        section["links"] = str(args.links.value)
+    if args.link_redirect_delay is not None:
+        section["link_redirect_delay"] = str(args.link_redirect_delay)
+    if args.videos is not None:
+        section["videos"] = "yes" if args.videos else "no"
+    if args.forums is not None:
+        section["forums"] = "yes" if args.forums else "no"
+    if args.http_timeout is not None:
+        section["http_timeout"] = str(args.http_timeout)
+
+    parser["auth:ilias"] = {}
+    auth_section = parser["auth:ilias"]
+    if args.credential_file is not None:
+        if args.username is not None:
+            raise ParserLoadError("--credential-file and --username can't be used together")
+        if args.keyring:
+            raise ParserLoadError("--credential-file and --keyring can't be used together")
+        auth_section["type"] = "credential-file"
+        auth_section["path"] = str(args.credential_file)
+    elif args.keyring:
+        auth_section["type"] = "keyring"
+    else:
+        auth_section["type"] = "simple"
+    if args.username is not None:
+        auth_section["username"] = args.username
--- a/PFERD/crawl/init.py
+++ b/PFERD/crawl/init.py
@ -4,7 +4,7 @@ from typing import Callable, Dict
 from ..auth import Authenticator
 from ..config import Config
 from .crawler import Crawler, CrawlError, CrawlerSection  # noqa: F401
-from .ilias import KitIliasWebCrawler, KitIliasWebCrawlerSection
+from .ilias import IliasWebCrawler, IliasWebCrawlerSection, KitIliasWebCrawler, KitIliasWebCrawlerSection
 from .kit_ipd_crawler import KitIpdCrawler, KitIpdCrawlerSection
 from .local_crawler import LocalCrawler, LocalCrawlerSection

@ -18,6 +18,8 @@ CrawlerConstructor = Callable[[
 CRAWLERS: Dict[str, CrawlerConstructor] = {
    "local": lambda n, s, c, a:
        LocalCrawler(n, LocalCrawlerSection(s), c),
+    "ilias-web": lambda n, s, c, a:
+        IliasWebCrawler(n, IliasWebCrawlerSection(s), c, a),
    "kit-ilias-web": lambda n, s, c, a:
        KitIliasWebCrawler(n, KitIliasWebCrawlerSection(s), c, a),
    "kit-ipd": lambda n, s, c, a:
--- a/PFERD/crawl/crawler.py
+++ b/PFERD/crawl/crawler.py
@ -149,9 +149,7 @@ class CrawlerSection(Section):
        return self.s.getboolean("skip", fallback=False)

    def output_dir(self, name: str) -> Path:
-        # TODO Use removeprefix() after switching to 3.9
-        if name.startswith("crawl:"):
-            name = name[len("crawl:"):]
+        name = name.removeprefix("crawl:")
        return Path(self.s.get("output_dir", name)).expanduser()

    def redownload(self) -> Redownload:
@ -258,6 +256,10 @@ class Crawler(ABC):
    def prev_report(self) -> Optional[Report]:
        return self._output_dir.prev_report

+    @property
+    def output_dir(self) -> OutputDirectory:
+        return self._output_dir
+
    @staticmethod
    async def gather(awaitables: Sequence[Awaitable[Any]]) -> List[Any]:
        """
@ -290,9 +292,40 @@ class Crawler(ABC):
        log.explain("Answer: Yes")
        return CrawlToken(self._limiter, path)

+    def should_try_download(
+            self,
+            path: PurePath,
+            *,
+            etag_differs: Optional[bool] = None,
+            mtime: Optional[datetime] = None,
+            redownload: Optional[Redownload] = None,
+            on_conflict: Optional[OnConflict] = None,
+    ) -> bool:
+        log.explain_topic(f"Decision: Should Download {fmt_path(path)}")
+
+        if self._transformer.transform(path) is None:
+            log.explain("Answer: No (ignored)")
+            return False
+
+        should_download = self._output_dir.should_try_download(
+            path,
+            etag_differs=etag_differs,
+            mtime=mtime,
+            redownload=redownload,
+            on_conflict=on_conflict
+        )
+        if should_download:
+            log.explain("Answer: Yes")
+            return True
+        else:
+            log.explain("Answer: No")
+            return False
+
    async def download(
            self,
            path: PurePath,
+            *,
+            etag_differs: Optional[bool] = None,
            mtime: Optional[datetime] = None,
            redownload: Optional[Redownload] = None,
            on_conflict: Optional[OnConflict] = None,
@ -307,7 +340,14 @@ class Crawler(ABC):
            log.status("[bold bright_black]", "Ignored", fmt_path(path))
            return None

-        fs_token = await self._output_dir.download(path, transformed_path, mtime, redownload, on_conflict)
+        fs_token = await self._output_dir.download(
+            path,
+            transformed_path,
+            etag_differs=etag_differs,
+            mtime=mtime,
+            redownload=redownload,
+            on_conflict=on_conflict
+        )
        if fs_token is None:
            log.explain("Answer: No")
            return None
--- a/PFERD/crawl/http_crawler.py
+++ b/PFERD/crawl/http_crawler.py
@ -1,12 +1,14 @@
 import asyncio
 import http.cookies
 import ssl
+from datetime import datetime
 from pathlib import Path, PurePath
-from typing import Any, Dict, List, Optional
+from typing import Any, Dict, List, Optional, Tuple, cast

 import aiohttp
 import certifi
 from aiohttp.client import ClientTimeout
+from bs4 import Tag

 from ..auth import Authenticator
 from ..config import Config
@ -15,10 +17,12 @@ from ..utils import fmt_real_path
 from ..version import NAME, VERSION
 from .crawler import Crawler, CrawlerSection

+ETAGS_CUSTOM_REPORT_VALUE_KEY = "etags"
+

 class HttpCrawlerSection(CrawlerSection):
    def http_timeout(self) -> float:
-        return self.s.getfloat("http_timeout", fallback=20)
+        return self.s.getfloat("http_timeout", fallback=30)


 class HttpCrawler(Crawler):
@ -169,6 +173,79 @@ class HttpCrawler(Crawler):
            log.warn(f"Failed to save cookies to {fmt_real_path(self._cookie_jar_path)}")
            log.warn(str(e))

+    @staticmethod
+    def get_folder_structure_from_heading_hierarchy(file_link: Tag, drop_h1: bool = False) -> PurePath:
+        """
+        Retrieves the hierarchy of headings associated with the give file link and constructs a folder
+        structure from them.
+
+        <h1> level headings usually only appear once and serve as the page title, so they would introduce
+        redundant nesting. To avoid this, <h1> headings are ignored via the drop_h1 parameter.
+        """
+
+        def find_associated_headings(tag: Tag, level: int) -> PurePath:
+            if level == 0 or (level == 1 and drop_h1):
+                return PurePath()
+
+            level_heading = cast(Optional[Tag], tag.find_previous(name=f"h{level}"))
+
+            if level_heading is None:
+                return find_associated_headings(tag, level - 1)
+
+            folder_name = level_heading.get_text().strip()
+            return find_associated_headings(level_heading, level - 1) / folder_name
+
+        # start at level <h3> because paragraph-level headings are usually too granular for folder names
+        return find_associated_headings(file_link, 3)
+
+    def _get_previous_etag_from_report(self, path: PurePath) -> Optional[str]:
+        """
+        If available, retrieves the entity tag for a given path which was stored in the previous report.
+        """
+        if not self._output_dir.prev_report:
+            return None
+
+        etags = self._output_dir.prev_report.get_custom_value(ETAGS_CUSTOM_REPORT_VALUE_KEY) or {}
+        return etags.get(str(path))
+
+    def _add_etag_to_report(self, path: PurePath, etag: Optional[str]) -> None:
+        """
+        Adds an entity tag for a given path to the report's custom values.
+        """
+        if not etag:
+            return
+
+        etags = self._output_dir.report.get_custom_value(ETAGS_CUSTOM_REPORT_VALUE_KEY) or {}
+        etags[str(path)] = etag
+        self._output_dir.report.add_custom_value(ETAGS_CUSTOM_REPORT_VALUE_KEY, etags)
+
+    async def _request_resource_version(self, resource_url: str) -> Tuple[Optional[str], Optional[datetime]]:
+        """
+        Requests the ETag and Last-Modified headers of a resource via a HEAD request.
+        If no entity tag / modification date can be obtained, the according value will be None.
+        """
+        try:
+            async with self.session.head(resource_url) as resp:
+                if resp.status != 200:
+                    return None, None
+
+                etag_header = resp.headers.get("ETag")
+                last_modified_header = resp.headers.get("Last-Modified")
+                last_modified = None
+
+                if last_modified_header:
+                    try:
+                        # https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Last-Modified#directives
+                        datetime_format = "%a, %d %b %Y %H:%M:%S GMT"
+                        last_modified = datetime.strptime(last_modified_header, datetime_format)
+                    except ValueError:
+                        # last_modified remains None
+                        pass
+
+                return etag_header, last_modified
+        except aiohttp.ClientError:
+            return None, None
+
    async def run(self) -> None:
        self._request_count = 0
        self._cookie_jar = aiohttp.CookieJar()
@ -186,7 +263,12 @@ class HttpCrawler(Crawler):
                    connect=self._http_timeout,
                    sock_connect=self._http_timeout,
                    sock_read=self._http_timeout,
-                )
+                ),
+                # See https://github.com/aio-libs/aiohttp/issues/6626
+                # Without this aiohttp will mangle the redirect header from Shibboleth, invalidating the
+                # passed signature. Shibboleth will not accept the broken signature and authentication will
+                # fail.
+                requote_redirect_url=False
        ) as session:
            self.session = session
            try:
--- a/PFERD/crawl/ilias/init.py
+++ b/PFERD/crawl/ilias/init.py
@ -1,3 +1,9 @@
-from .kit_ilias_web_crawler import KitIliasWebCrawler, KitIliasWebCrawlerSection
+from .kit_ilias_web_crawler import (IliasWebCrawler, IliasWebCrawlerSection, KitIliasWebCrawler,
+                                    KitIliasWebCrawlerSection)

-__all__ = ["KitIliasWebCrawler", "KitIliasWebCrawlerSection"]
+__all__ = [
+    "IliasWebCrawler",
+    "IliasWebCrawlerSection",
+    "KitIliasWebCrawler",
+    "KitIliasWebCrawlerSection",
+]
--- a/PFERD/crawl/ilias/async_helper.py
+++ b/PFERD/crawl/ilias/async_helper.py
@ -0,0 +1,40 @@
+import asyncio
+from typing import Any, Callable, Optional
+
+import aiohttp
+
+from ...logging import log
+from ..crawler import AWrapped, CrawlError, CrawlWarning
+
+
+def _iorepeat(attempts: int, name: str, failure_is_error: bool = False) -> Callable[[AWrapped], AWrapped]:
+    def decorator(f: AWrapped) -> AWrapped:
+        async def wrapper(*args: Any, **kwargs: Any) -> Optional[Any]:
+            last_exception: Optional[BaseException] = None
+            for round in range(attempts):
+                try:
+                    return await f(*args, **kwargs)
+                except aiohttp.ContentTypeError:  # invalid content type
+                    raise CrawlWarning("ILIAS returned an invalid content type")
+                except aiohttp.TooManyRedirects:
+                    raise CrawlWarning("Got stuck in a redirect loop")
+                except aiohttp.ClientPayloadError as e:  # encoding or not enough bytes
+                    last_exception = e
+                except aiohttp.ClientConnectionError as e:  # e.g. timeout, disconnect, resolve failed, etc.
+                    last_exception = e
+                except asyncio.exceptions.TimeoutError as e:  # explicit http timeouts in HttpCrawler
+                    last_exception = e
+                log.explain_topic(f"Retrying operation {name}. Retries left: {attempts - 1 - round}")
+                log.explain(f"Last exception: {last_exception!r}")
+
+            if last_exception:
+                message = f"Error in I/O Operation: {last_exception!r}"
+                if failure_is_error:
+                    raise CrawlError(message) from last_exception
+                else:
+                    raise CrawlWarning(message) from last_exception
+            raise CrawlError("Impossible return in ilias _iorepeat")
+
+        return wrapper  # type: ignore
+
+    return decorator
--- a/PFERD/crawl/ilias/file_templates.py
+++ b/PFERD/crawl/ilias/file_templates.py
@ -1,5 +1,5 @@
 from enum import Enum
-from typing import Optional
+from typing import Optional, cast

 import bs4

@ -126,6 +126,88 @@ _learning_module_template = """
 </html>
 """

+_forum_thread_template = """
+<!DOCTYPE html>
+<html lang="en">
+    <head>
+        <meta charset="UTF-8">
+        <title>ILIAS - Forum: {{name}}</title>
+        <style>
+            * {
+                box-sizing: border-box;
+            }
+            body {
+                font-family: 'Open Sans', Verdana, Arial, Helvetica, sans-serif;
+                padding: 8px;
+            }
+            ul, ol, p {
+                margin: 1.2em 0;
+            }
+            p {
+                margin-top: 8px;
+                margin-bottom: 8px;
+            }
+            a {
+                color: #00876c;
+                text-decoration: none;
+                cursor: pointer;
+            }
+            a:hover {
+                text-decoration: underline;
+            }
+            body > p:first-child > span:first-child {
+                font-size: 1.6em;
+            }
+            body > p:first-child > span:first-child ~ span.default {
+                display: inline-block;
+                font-size: 1.2em;
+                padding-bottom: 8px;
+            }
+            .ilFrmPostContent {
+                margin-top: 8px;
+                max-width: 64em;
+            }
+            .ilFrmPostContent > *:first-child {
+                margin-top: 0px;
+            }
+            .ilFrmPostTitle {
+                margin-top: 24px;
+                color: #00876c;
+                font-weight: bold;
+            }
+            #ilFrmPostList {
+                list-style: none;
+                padding-left: 0;
+            }
+            li.ilFrmPostRow {
+                padding: 3px 0 3px 3px;
+                margin-bottom: 24px;
+                border-left: 6px solid #dddddd;
+            }
+            .ilFrmPostRow > div {
+                display: flex;
+            }
+            .ilFrmPostImage img {
+                margin: 0 !important;
+                padding: 6px 9px 9px 6px;
+            }
+            .ilUserIcon {
+                width: 115px;
+            }
+            .small {
+                text-decoration: none;
+                font-size: 0.75rem;
+                color: #6f6f6f;
+            }
+        </style>
+    </head>
+    <body>
+    {{heading}}
+    {{content}}
+    </body>
+</html>
+""".strip()  # noqa: E501 line too long
+

 def learning_module_template(body: bs4.Tag, name: str, prev: Optional[str], next: Optional[str]) -> str:
    # Seems to be comments, ignore those.
@ -139,13 +221,13 @@ def learning_module_template(body: bs4.Tag, name: str, prev: Optional[str], next
        </div>
    """
    if prev and body.select_one(".ilc_page_lnav_LeftNavigation"):
-        text = body.select_one(".ilc_page_lnav_LeftNavigation").getText().strip()
+        text = cast(bs4.Tag, body.select_one(".ilc_page_lnav_LeftNavigation")).get_text().strip()
        left = f'<a href="{prev}">{text}</a>'
    else:
        left = "<span></span>"

    if next and body.select_one(".ilc_page_rnav_RightNavigation"):
-        text = body.select_one(".ilc_page_rnav_RightNavigation").getText().strip()
+        text = cast(bs4.Tag, body.select_one(".ilc_page_rnav_RightNavigation")).get_text().strip()
        right = f'<a href="{next}">{text}</a>'
    else:
        right = "<span></span>"
@ -160,8 +242,17 @@ def learning_module_template(body: bs4.Tag, name: str, prev: Optional[str], next
            "{{left}}", left).replace("{{right}}", right).encode())
        )

-    body = body.prettify()
-    return _learning_module_template.replace("{{body}}", body).replace("{{name}}", name)
+    body_str = cast(str, body.prettify())
+    return _learning_module_template.replace("{{body}}", body_str).replace("{{name}}", name)
+
+
+def forum_thread_template(name: str, url: str, heading: bs4.Tag, content: bs4.Tag) -> str:
+    if title := cast(Optional[bs4.Tag], heading.find(name="b")):
+        title.wrap(bs4.Tag(name="a", attrs={"href": url}))
+    return _forum_thread_template \
+        .replace("{{name}}", name) \
+        .replace("{{heading}}", cast(str, heading.prettify())) \
+        .replace("{{content}}", cast(str, content.prettify()))


 class Links(Enum):
--- a/PFERD/crawl/ilias/ilias_html_cleaner.py
+++ b/PFERD/crawl/ilias/ilias_html_cleaner.py
@ -1,3 +1,5 @@
+from typing import cast
+
 from bs4 import BeautifulSoup, Comment, Tag

 _STYLE_TAG_CONTENT = """
@ -12,6 +14,13 @@ _STYLE_TAG_CONTENT = """
      font-weight: bold;
    }

+    .row-flex {
+      display: flex;
+    }
+    .row-flex-wrap {
+      flex-wrap: wrap;
+    }
+
    .accordion-head {
      background-color: #f5f7fa;
      padding: 0.5rem 0;
@ -63,18 +72,18 @@ def insert_base_markup(soup: BeautifulSoup) -> BeautifulSoup:


 def clean(soup: BeautifulSoup) -> BeautifulSoup:
-    for block in soup.find_all(class_=lambda x: x in _ARTICLE_WORTHY_CLASSES):
+    for block in cast(list[Tag], soup.find_all(class_=lambda x: x in _ARTICLE_WORTHY_CLASSES)):
        block.name = "article"

-    for block in soup.find_all("h3"):
+    for block in cast(list[Tag], soup.find_all("h3")):
        block.name = "div"

-    for block in soup.find_all("h1"):
+    for block in cast(list[Tag], soup.find_all("h1")):
        block.name = "h3"

-    for block in soup.find_all(class_="ilc_va_ihcap_VAccordIHeadCap"):
+    for block in cast(list[Tag], soup.find_all(class_="ilc_va_ihcap_VAccordIHeadCap")):
        block.name = "h3"
-        block["class"] += ["accordion-head"]
+        block["class"] += ["accordion-head"]  # type: ignore

    for dummy in soup.select(".ilc_text_block_Standard.ilc_Paragraph"):
        children = list(dummy.children)
@ -85,7 +94,12 @@ def clean(soup: BeautifulSoup) -> BeautifulSoup:
        if isinstance(type(children[0]), Comment):
            dummy.decompose()

-    for hrule_imposter in soup.find_all(class_="ilc_section_Separator"):
+    # Delete video figures, as they can not be internalized anyway
+    for video in soup.select(".ilc_media_cont_MediaContainerHighlighted .ilPageVideo"):
+        if figure := video.find_parent("figure"):
+            figure.decompose()
+
+    for hrule_imposter in cast(list[Tag], soup.find_all(class_="ilc_section_Separator")):
        hrule_imposter.insert(0, soup.new_tag("hr"))

    return soup
--- a/PFERD/crawl/ilias/ilias_web_crawler.py
+++ b/PFERD/crawl/ilias/ilias_web_crawler.py
--- a/PFERD/crawl/ilias/kit_ilias_html.py
+++ b/PFERD/crawl/ilias/kit_ilias_html.py
--- a/PFERD/crawl/ilias/kit_ilias_web_crawler.py
+++ b/PFERD/crawl/ilias/kit_ilias_web_crawler.py
--- a/PFERD/crawl/ilias/shibboleth_login.py
+++ b/PFERD/crawl/ilias/shibboleth_login.py
@ -0,0 +1,129 @@
+from typing import Any, Optional, cast
+
+import aiohttp
+import yarl
+from bs4 import BeautifulSoup, Tag
+
+from ...auth import Authenticator, TfaAuthenticator
+from ...logging import log
+from ...utils import soupify
+from ..crawler import CrawlError
+
+
+class ShibbolethLogin:
+    """
+    Login via shibboleth system.
+    """
+
+    def __init__(
+        self, ilias_url: str, authenticator: Authenticator, tfa_authenticator: Optional[Authenticator]
+    ) -> None:
+        self._ilias_url = ilias_url
+        self._auth = authenticator
+        self._tfa_auth = tfa_authenticator
+
+    async def login(self, sess: aiohttp.ClientSession) -> None:
+        """
+        Performs the ILIAS Shibboleth authentication dance and saves the login
+        cookies it receieves.
+
+        This function should only be called whenever it is detected that you're
+        not logged in. The cookies obtained should be good for a few minutes,
+        maybe even an hour or two.
+        """
+
+        # Equivalent: Click on "Mit KIT-Account anmelden" button in
+        # https://ilias.studium.kit.edu/login.php
+        url = f"{self._ilias_url}/shib_login.php"
+        async with sess.get(url) as response:
+            shib_url = response.url
+            if str(shib_url).startswith(self._ilias_url):
+                log.explain(
+                    "ILIAS recognized our shib token and logged us in in the background, returning"
+                )
+                return
+            soup: BeautifulSoup = soupify(await response.read())
+
+        # Attempt to login using credentials, if necessary
+        while not self._login_successful(soup):
+            # Searching the form here so that this fails before asking for
+            # credentials rather than after asking.
+            form = cast(Tag, soup.find("form", {"method": "post"}))
+            action = cast(str, form["action"])
+
+            # Equivalent: Enter credentials in
+            # https://idp.scc.kit.edu/idp/profile/SAML2/Redirect/SSO
+            url = str(shib_url.origin()) + action
+            username, password = await self._auth.credentials()
+            data = {
+                "_eventId_proceed": "",
+                "j_username": username,
+                "j_password": password,
+                "fudis_web_authn_assertion_input": "",
+            }
+            if csrf_token_input := form.find("input", {"name": "csrf_token"}):
+                data["csrf_token"] = csrf_token_input["value"]  # type: ignore
+            soup = await _post(sess, url, data)
+
+            if soup.find(id="attributeRelease"):
+                raise CrawlError(
+                    "ILIAS Shibboleth entitlements changed! "
+                    "Please log in once in your browser and review them"
+                )
+
+            if self._tfa_required(soup):
+                soup = await self._authenticate_tfa(sess, soup, shib_url)
+
+            if not self._login_successful(soup):
+                self._auth.invalidate_credentials()
+
+        # Equivalent: Being redirected via JS automatically
+        # (or clicking "Continue" if you have JS disabled)
+        relay_state = cast(Tag, soup.find("input", {"name": "RelayState"}))
+        saml_response = cast(Tag, soup.find("input", {"name": "SAMLResponse"}))
+        url = form = soup.find("form", {"method": "post"})["action"]  # type: ignore
+        data = {  # using the info obtained in the while loop above
+            "RelayState": cast(str, relay_state["value"]),
+            "SAMLResponse": cast(str, saml_response["value"]),
+        }
+        await sess.post(cast(str, url), data=data)
+
+    async def _authenticate_tfa(
+        self, session: aiohttp.ClientSession, soup: BeautifulSoup, shib_url: yarl.URL
+    ) -> BeautifulSoup:
+        if not self._tfa_auth:
+            self._tfa_auth = TfaAuthenticator("ilias-anon-tfa")
+
+        tfa_token = await self._tfa_auth.password()
+
+        # Searching the form here so that this fails before asking for
+        # credentials rather than after asking.
+        form = cast(Tag, soup.find("form", {"method": "post"}))
+        action = cast(str, form["action"])
+
+        # Equivalent: Enter token in
+        # https://idp.scc.kit.edu/idp/profile/SAML2/Redirect/SSO
+        url = str(shib_url.origin()) + action
+        username, password = await self._auth.credentials()
+        data = {
+            "_eventId_proceed": "",
+            "fudis_otp_input": tfa_token,
+        }
+        if csrf_token_input := form.find("input", {"name": "csrf_token"}):
+            data["csrf_token"] = csrf_token_input["value"]  # type: ignore
+        return await _post(session, url, data)
+
+    @staticmethod
+    def _login_successful(soup: BeautifulSoup) -> bool:
+        relay_state = soup.find("input", {"name": "RelayState"})
+        saml_response = soup.find("input", {"name": "SAMLResponse"})
+        return relay_state is not None and saml_response is not None
+
+    @staticmethod
+    def _tfa_required(soup: BeautifulSoup) -> bool:
+        return soup.find(id="fudiscr-form") is not None
+
+
+async def _post(session: aiohttp.ClientSession, url: str, data: Any) -> BeautifulSoup:
+    async with session.post(url, data=data) as response:
+        return soupify(await response.read())
--- a/PFERD/crawl/kit_ipd_crawler.py
+++ b/PFERD/crawl/kit_ipd_crawler.py
@ -1,8 +1,9 @@
 import os
 import re
 from dataclasses import dataclass
+from datetime import datetime
 from pathlib import PurePath
-from typing import Awaitable, List, Optional, Pattern, Set, Tuple, Union
+from typing import Any, Awaitable, Generator, Iterable, List, Optional, Pattern, Tuple, Union, cast
 from urllib.parse import urljoin

 from bs4 import BeautifulSoup, Tag
@ -31,24 +32,24 @@ class KitIpdCrawlerSection(HttpCrawlerSection):
        return re.compile(regex)


-@dataclass(unsafe_hash=True)
+@dataclass
 class KitIpdFile:
    name: str
    url: str

+    def explain(self) -> None:
+        log.explain(f"File {self.name!r} (href={self.url!r})")
+

@dataclass
 class KitIpdFolder:
    name: str
-    files: List[KitIpdFile]
+    entries: List[Union[KitIpdFile, "KitIpdFolder"]]

    def explain(self) -> None:
        log.explain_topic(f"Folder {self.name!r}")
-        for file in self.files:
-            log.explain(f"File {file.name!r} (href={file.url!r})")
-
-    def __hash__(self) -> int:
-        return self.name.__hash__()
+        for entry in self.entries:
+            entry.explain()


 class KitIpdCrawler(HttpCrawler):
@ -72,81 +73,96 @@ class KitIpdCrawler(HttpCrawler):

        async with maybe_cl:
            for item in await self._fetch_items():
+                item.explain()
                if isinstance(item, KitIpdFolder):
-                    tasks.append(self._crawl_folder(item))
+                    tasks.append(self._crawl_folder(PurePath("."), item))
                else:
-                    # Orphan files are placed in the root folder
-                    tasks.append(self._download_file(PurePath("."), item))
+                    log.explain_topic(f"Orphan file {item.name!r} (href={item.url!r})")
+                    log.explain("Attributing it to root folder")
+                    # do this here to at least be sequential and not parallel (rate limiting is hard, as the
+                    # crawl abstraction does not hold for these requests)
+                    etag, mtime = await self._request_resource_version(item.url)
+                    tasks.append(self._download_file(PurePath("."), item, etag, mtime))

        await self.gather(tasks)

-    async def _crawl_folder(self, folder: KitIpdFolder) -> None:
-        path = PurePath(folder.name)
+    async def _crawl_folder(self, parent: PurePath, folder: KitIpdFolder) -> None:
+        path = parent / folder.name
        if not await self.crawl(path):
            return

-        tasks = [self._download_file(path, file) for file in folder.files]
+        tasks = []
+        for entry in folder.entries:
+            if isinstance(entry, KitIpdFolder):
+                tasks.append(self._crawl_folder(path, entry))
+            else:
+                # do this here to at least be sequential and not parallel (rate limiting is hard, as the crawl
+                # abstraction does not hold for these requests)
+                etag, mtime = await self._request_resource_version(entry.url)
+                tasks.append(self._download_file(path, entry, etag, mtime))

        await self.gather(tasks)

-    async def _download_file(self, parent: PurePath, file: KitIpdFile) -> None:
+    async def _download_file(
+        self,
+        parent: PurePath,
+        file: KitIpdFile,
+        etag: Optional[str],
+        mtime: Optional[datetime]
+    ) -> None:
        element_path = parent / file.name
-        maybe_dl = await self.download(element_path)
+
+        prev_etag = self._get_previous_etag_from_report(element_path)
+        etag_differs = None if prev_etag is None else prev_etag != etag
+
+        maybe_dl = await self.download(element_path, etag_differs=etag_differs, mtime=mtime)
        if not maybe_dl:
+            # keep storing the known file's etag
+            if prev_etag:
+                self._add_etag_to_report(element_path, prev_etag)
            return

        async with maybe_dl as (bar, sink):
-            await self._stream_from_url(file.url, sink, bar)
+            await self._stream_from_url(file.url, element_path, sink, bar)

-    async def _fetch_items(self) -> Set[Union[KitIpdFile, KitIpdFolder]]:
+    async def _fetch_items(self) -> Iterable[Union[KitIpdFile, KitIpdFolder]]:
        page, url = await self.get_page()
        elements: List[Tag] = self._find_file_links(page)
-        items: Set[Union[KitIpdFile, KitIpdFolder]] = set()

+        # do not add unnecessary nesting for a single <h1> heading
+        drop_h1: bool = len(page.find_all(name="h1")) <= 1
+
+        folder_tree: KitIpdFolder = KitIpdFolder(".", [])
        for element in elements:
-            folder_label = self._find_folder_label(element)
-            if folder_label:
-                folder = self._extract_folder(folder_label, url)
-                if folder not in items:
-                    items.add(folder)
-                    folder.explain()
-            else:
+            parent = HttpCrawler.get_folder_structure_from_heading_hierarchy(element, drop_h1)
            file = self._extract_file(element, url)
-                items.add(file)
-                log.explain_topic(f"Orphan file {file.name!r} (href={file.url!r})")
-                log.explain("Attributing it to root folder")

-        return items
+            current_folder: KitIpdFolder = folder_tree
+            for folder_name in parent.parts:
+                # helps the type checker to verify that current_folder is indeed a folder
+                def subfolders() -> Generator[KitIpdFolder, Any, None]:
+                    return (entry for entry in current_folder.entries if isinstance(entry, KitIpdFolder))

-    def _extract_folder(self, folder_tag: Tag, url: str) -> KitIpdFolder:
-        files: List[KitIpdFile] = []
-        name = folder_tag.getText().strip()
+                if not any(entry.name == folder_name for entry in subfolders()):
+                    current_folder.entries.append(KitIpdFolder(folder_name, []))
+                current_folder = next(entry for entry in subfolders() if entry.name == folder_name)

-        container: Tag = folder_tag.findNextSibling(name="table")
-        for link in self._find_file_links(container):
-            files.append(self._extract_file(link, url))
+            current_folder.entries.append(file)

-        return KitIpdFolder(name, files)
-
-    @staticmethod
-    def _find_folder_label(file_link: Tag) -> Optional[Tag]:
-        enclosing_table: Tag = file_link.findParent(name="table")
-        if enclosing_table is None:
-            return None
-        return enclosing_table.findPreviousSibling(name=re.compile("^h[1-6]$"))
+        return folder_tree.entries

    def _extract_file(self, link: Tag, url: str) -> KitIpdFile:
        url = self._abs_url_from_link(url, link)
        name = os.path.basename(url)
        return KitIpdFile(name, url)

-    def _find_file_links(self, tag: Union[Tag, BeautifulSoup]) -> List[Tag]:
-        return tag.findAll(name="a", attrs={"href": self._file_regex})
+    def _find_file_links(self, tag: Union[Tag, BeautifulSoup]) -> list[Tag]:
+        return cast(list[Tag], tag.find_all(name="a", attrs={"href": self._file_regex}))

    def _abs_url_from_link(self, url: str, link_tag: Tag) -> str:
-        return urljoin(url, link_tag.get("href"))
+        return urljoin(url, cast(str, link_tag.get("href")))

-    async def _stream_from_url(self, url: str, sink: FileSink, bar: ProgressBar) -> None:
+    async def _stream_from_url(self, url: str, path: PurePath, sink: FileSink, bar: ProgressBar) -> None:
        async with self.session.get(url, allow_redirects=False) as resp:
            if resp.status == 403:
                raise CrawlError("Received a 403. Are you within the KIT network/VPN?")
@ -159,6 +175,8 @@ class KitIpdCrawler(HttpCrawler):

            sink.done()

+            self._add_etag_to_report(path, resp.headers.get("ETag"))
+
    async def get_page(self) -> Tuple[BeautifulSoup, str]:
        async with self.session.get(self._url) as request:
            # The web page for Algorithmen für Routenplanung contains some
--- a/PFERD/logging.py
+++ b/PFERD/logging.py
@ -1,9 +1,8 @@
 import asyncio
 import sys
 import traceback
-from contextlib import asynccontextmanager, contextmanager
-# TODO In Python 3.9 and above, ContextManager is deprecated
-from typing import AsyncIterator, ContextManager, Iterator, List, Optional
+from contextlib import AbstractContextManager, asynccontextmanager, contextmanager
+from typing import AsyncIterator, Iterator, List, Optional

 from rich.console import Console, Group
 from rich.live import Live
@ -261,7 +260,7 @@ directly or as a GitHub issue: https://github.com/Garmelon/PFERD/issues/new
            action: str,
            text: str,
            total: Optional[float] = None,
-    ) -> ContextManager[ProgressBar]:
+    ) -> AbstractContextManager[ProgressBar]:
        """
        Allows markup in the "style" argument which will be applied to the
        "action" string.
@ -277,7 +276,7 @@ directly or as a GitHub issue: https://github.com/Garmelon/PFERD/issues/new
            action: str,
            text: str,
            total: Optional[float] = None,
-    ) -> ContextManager[ProgressBar]:
+    ) -> AbstractContextManager[ProgressBar]:
        """
        Allows markup in the "style" argument which will be applied to the
        "action" string.
--- a/PFERD/output_dir.py
+++ b/PFERD/output_dir.py
@ -57,6 +57,7 @@ class OnConflict(Enum):

@dataclass
 class Heuristics:
+    etag_differs: Optional[bool]
    mtime: Optional[datetime]


@ -233,8 +234,16 @@ class OutputDirectory:

        remote_newer = None

+        # ETag should be a more reliable indicator than mtime, so we check it first
+        if heuristics.etag_differs is not None:
+            remote_newer = heuristics.etag_differs
+            if remote_newer:
+                log.explain("Remote file's entity tag differs")
+            else:
+                log.explain("Remote file's entity tag is the same")
+
        # Python on Windows crashes when faced with timestamps around the unix epoch
-        if heuristics.mtime and (os.name != "nt" or heuristics.mtime.year > 1970):
+        if remote_newer is None and heuristics.mtime and (os.name != "nt" or heuristics.mtime.year > 1970):
            mtime = heuristics.mtime
            remote_newer = mtime.timestamp() > stat.st_mtime
            if remote_newer:
@ -362,10 +371,28 @@ class OutputDirectory:

        raise OutputDirError("Failed to create temporary file")

+    def should_try_download(
+        self,
+        path: PurePath,
+        *,
+        etag_differs: Optional[bool] = None,
+        mtime: Optional[datetime] = None,
+        redownload: Optional[Redownload] = None,
+        on_conflict: Optional[OnConflict] = None,
+    ) -> bool:
+        heuristics = Heuristics(etag_differs, mtime)
+        redownload = self._redownload if redownload is None else redownload
+        on_conflict = self._on_conflict if on_conflict is None else on_conflict
+        local_path = self.resolve(path)
+
+        return self._should_download(local_path, heuristics, redownload, on_conflict)
+
    async def download(
            self,
            remote_path: PurePath,
            path: PurePath,
+            *,
+            etag_differs: Optional[bool] = None,
            mtime: Optional[datetime] = None,
            redownload: Optional[Redownload] = None,
            on_conflict: Optional[OnConflict] = None,
@ -375,7 +402,7 @@ class OutputDirectory:
        MarkConflictError.
        """

-        heuristics = Heuristics(mtime)
+        heuristics = Heuristics(etag_differs, mtime)
        redownload = self._redownload if redownload is None else redownload
        on_conflict = self._on_conflict if on_conflict is None else on_conflict
        local_path = self.resolve(path)
--- a/PFERD/pferd.py
+++ b/PFERD/pferd.py
@ -1,4 +1,4 @@
-from pathlib import Path
+from pathlib import Path, PurePath
 from typing import Dict, List, Optional

 from rich.markup import escape
@ -168,19 +168,24 @@ class Pferd:
            log.report("")
            log.report(f"[bold bright_cyan]Report[/] for {escape(name)}")

+            def fmt_path_link(relative_path: PurePath) -> str:
+                # We need to URL-encode the path because it might contain spaces or special characters
+                link = crawler.output_dir.resolve(relative_path).absolute().as_uri()
+                return f"[link={link}]{fmt_path(relative_path)}[/link]"
+
            something_changed = False
            for path in sorted(crawler.report.added_files):
                something_changed = True
-                log.report(f"  [bold bright_green]Added[/] {fmt_path(path)}")
+                log.report(f"  [bold bright_green]Added[/] {fmt_path_link(path)}")
            for path in sorted(crawler.report.changed_files):
                something_changed = True
-                log.report(f"  [bold bright_yellow]Changed[/] {fmt_path(path)}")
+                log.report(f"  [bold bright_yellow]Changed[/] {fmt_path_link(path)}")
            for path in sorted(crawler.report.deleted_files):
                something_changed = True
                log.report(f"  [bold bright_magenta]Deleted[/] {fmt_path(path)}")
            for path in sorted(crawler.report.not_deleted_files):
                something_changed = True
-                log.report_not_deleted(f"  [bold bright_magenta]Not deleted[/] {fmt_path(path)}")
+                log.report_not_deleted(f"  [bold bright_magenta]Not deleted[/] {fmt_path_link(path)}")

            for warning in crawler.report.encountered_warnings:
                something_changed = True
--- a/PFERD/report.py
+++ b/PFERD/report.py
@ -34,15 +34,6 @@ class MarkConflictError(Exception):
        self.collides_with = collides_with


-# TODO Use PurePath.is_relative_to when updating to 3.9
-def is_relative_to(a: PurePath, b: PurePath) -> bool:
-    try:
-        a.relative_to(b)
-        return True
-    except ValueError:
-        return False
-
-
 class Report:
    """
    A report of a synchronization. Includes all files found by the crawler, as
@ -173,7 +164,7 @@ class Report:
            if path == other:
                raise MarkDuplicateError(path)

-            if is_relative_to(path, other) or is_relative_to(other, path):
+            if path.is_relative_to(other) or other.is_relative_to(path):
                raise MarkConflictError(path, other)

        self.known_files.add(path)
--- a/PFERD/transformer.py
+++ b/PFERD/transformer.py
@ -110,6 +110,10 @@ class ExactReTf(Transformation):
            except ValueError:
                pass

+        named_groups: Dict[str, str] = match.groupdict()
+        for name, capture in named_groups.items():
+            locals_dir[name] = capture
+
        result = eval(f"f{right!r}", {}, locals_dir)
        return Transformed(PurePath(result))

--- a/PFERD/version.py
+++ b/PFERD/version.py
@ -1,2 +1,2 @@
 NAME = "PFERD"
-VERSION = "3.5.2"
+VERSION = "3.8.0"
--- a/README.md
+++ b/README.md
@ -17,7 +17,7 @@ Binaries for Linux, Windows and Mac can be downloaded directly from the

 ### With pip

-Ensure you have at least Python 3.9 installed. Run the following command to
+Ensure you have at least Python 3.11 installed. Run the following command to
 install PFERD or upgrade it to the latest version:

 ```
@ -56,6 +56,17 @@ Also, you can download most ILIAS pages directly like this:
 $ pferd kit-ilias-web <url> <output_directory>
 ```

+PFERD supports other ILIAS instances as well, using the `ilias-web` crawler (see
+the [config section on `ilias-web`](CONFIG.md#the-ilias-web-crawler) for more
+detail on the `base-url` and `client-id` parameters):
+
+```
+$ pferd ilias-web \
+    --base-url https://ilias.my-university.example \
+    --client-id My_University desktop \
+    <output_directory>
+```
+
 However, the CLI only lets you download a single thing at a time, and the
 resulting command can grow long quite quickly. Because of this, PFERD can also
 be used with a config file.
--- a/flake.lock
+++ b/flake.lock
@ -2,16 +2,16 @@
  "nodes": {
    "nixpkgs": {
      "locked": {
-        "lastModified": 1708979614,
-        "narHash": "sha256-FWLWmYojIg6TeqxSnHkKpHu5SGnFP5um1uUjH+wRV6g=",
+        "lastModified": 1744440957,
+        "narHash": "sha256-FHlSkNqFmPxPJvy+6fNLaNeWnF1lZSgqVCl/eWaJRc4=",
        "owner": "NixOS",
        "repo": "nixpkgs",
-        "rev": "b7ee09cf5614b02d289cd86fcfa6f24d4e078c2a",
+        "rev": "26d499fc9f1d567283d5d56fcf367edd815dba1d",
        "type": "github"
      },
      "original": {
        "owner": "NixOS",
-        "ref": "nixos-23.11",
+        "ref": "nixos-24.11",
        "repo": "nixpkgs",
        "type": "github"
      }
--- a/flake.nix
+++ b/flake.nix
@ -2,7 +2,7 @@
  description = "Tool for downloading course-related files from ILIAS";

  inputs = {
-    nixpkgs.url = "github:NixOS/nixpkgs/nixos-23.11";
+    nixpkgs.url = "github:NixOS/nixpkgs/nixos-24.11";
  };

  outputs = { self, nixpkgs }:
--- a/mypy.ini
+++ b/mypy.ini
@ -1,11 +0,0 @@
-[mypy]
-disallow_any_generics = True
-disallow_untyped_defs = True
-disallow_incomplete_defs = True
-no_implicit_optional = True
-warn_unused_ignores = True
-warn_unreachable = True
-show_error_context = True
-
-[mypy-rich.*,bs4,keyring]
-ignore_missing_imports = True
--- a/pyproject.toml
+++ b/pyproject.toml
@ -1,3 +1,42 @@
 [build-system]
 requires = ["setuptools", "wheel"]
 build-backend = "setuptools.build_meta"
+
+[project]
+name = "PFERD"
+dependencies = [
+  "aiohttp>=3.8.1",
+  "beautifulsoup4>=4.10.0",
+  "rich>=11.0.0",
+  "keyring>=23.5.0",
+  "certifi>=2021.10.8"
+]
+dynamic = ["version"]
+requires-python = ">=3.11"
+
+[project.scripts]
+pferd = "PFERD.__main__:main"
+
+[tool.setuptools.dynamic]
+version = {attr = "PFERD.version.VERSION"}
+
+[tool.flake8]
+max-line-length = 110
+
+[tool.isort]
+line_length = 110
+
+[tool.autopep8]
+max_line_length = 110
+in-place = true
+recursive = true
+
+[tool.mypy]
+disallow_any_generics = true
+disallow_untyped_defs = true
+disallow_incomplete_defs = true
+no_implicit_optional = true
+warn_unused_ignores = true
+warn_unreachable = true
+show_error_context = true
+ignore_missing_imports = true
--- a/scripts/bump-version
+++ b/scripts/bump-version
@ -1,8 +1,8 @@
 #!/usr/bin/env python3

 import argparse
-import time
 import re
+import time
 from subprocess import run


--- a/scripts/check
+++ b/scripts/check
@ -2,5 +2,5 @@

 set -e

-mypy PFERD
+mypy .
 flake8 PFERD
--- a/scripts/format
+++ b/scripts/format
@ -2,5 +2,5 @@

 set -e

-autopep8 --recursive --in-place PFERD
-isort PFERD
+autopep8 .
+isort .
--- a/scripts/setup
+++ b/scripts/setup
@ -13,5 +13,5 @@ pip install --upgrade setuptools
 pip install --editable .

 # Installing tools and type hints
-pip install --upgrade mypy flake8 autopep8 isort pyinstaller
+pip install --upgrade mypy flake8 flake8-pyproject autopep8 isort pyinstaller
 pip install --upgrade types-chardet types-certifi
--- a/setup.cfg
+++ b/setup.cfg
@ -1,23 +0,0 @@
-[metadata]
-name = PFERD
-version = attr: PFERD.version.VERSION
-
-[options]
-packages = find:
-python_requires = >=3.9
-install_requires =
-  aiohttp>=3.8.1
-  beautifulsoup4>=4.10.0
-  rich>=11.0.0
-  keyring>=23.5.0
-  certifi>=2021.10.8
-
-[options.entry_points]
-console_scripts =
-  pferd = PFERD.__main__:main
-
-[flake8]
-max_line_length = 110
-
-[isort]
-line_length = 110
Author	SHA1	Message	Date
I-Al-Istannen	7291382430	Bump version to 3.8.0	2025-04-15 11:32:22 +02:00
I-Al-Istannen	1a430ad5d1	Update minimum Python version to 3.11	2025-04-15 11:31:39 +02:00
I-Al-Istannen	f6bdeb6b9d	Support ILIAS 9	2025-04-15 11:19:53 +02:00
I-Al-Istannen	63f25277b0	Fix crawling of empty forum threads	2025-03-09 23:44:25 +01:00
I-Al-Istannen	c8eff04ae0	Make thread titles link to original ILIAS thread	2025-02-19 16:23:20 +01:00
I-Al-Istannen	edc482cdf4	Internalize images in forum threads	2025-02-19 16:23:20 +01:00
I-Al-Istannen	72cd0f77e2	Prettify forum thread exports Co-authored-by: Tim <me@scriptim.dev>	2025-02-19 16:23:20 +01:00
I-Al-Istannen	be175f9347	Download only new/updated forum threads	2025-02-19 16:16:37 +01:00
I-Al-Istannen	ba2833dba5	Crawl all threads in a forum Before this patch the row count was unconditionally changed to 800. This patch tries to detect how many rows the forum has and then fetches this amount, if it is larger than 800.	2025-02-19 12:19:33 +01:00
I-Al-Istannen	2f0e792670	Increase default http timeout to 30 Otherwise larger forums will fail to download in time	2025-02-19 12:19:13 +01:00
I-Al-Istannen	5f88539f7e	Fix page size increase for forum threads	2025-02-19 12:19:11 +01:00
I-Al-Istannen	bd9d7efe64	"Fix" mypy errors Thank you mypy, very cool. These types make things so much better. They don't just complicate everything and don't really help because they can not detect that an element queried by a tag is no navigable string...	2025-02-19 12:15:41 +01:00
Aurelia	16a2dd5b15	fix: totp	2025-02-19 12:15:41 +01:00
I-Al-Istannen	678283d341	Use Python facilities to convert paths to file:// urls	2024-11-15 00:09:11 +01:00
I-Al-Istannen	287173b0b1	Bump version to 3.7.0	2024-11-13 20:38:27 +01:00
I-Al-Istannen	712217e959	Handle groups in cards	2024-11-11 12:53:08 +01:00
I-Al-Istannen	6dda4c55a8	Add doctype header to forum threads This should fix mimetype detection on most systems and is more relevant now that the report is clickable	2024-11-05 18:36:21 +01:00
PinieP	596b6a7688	Add support for non-KIT shibboleth login (#98 ) Co-authored-by: Mr-Pine <git@mr-pine.de> Co-authored-by: I-Al-Istannen <I-Al-Istannen@users.noreply.github.com>	2024-11-05 18:30:34 +01:00
Tim	5983200247	Treat headings as folders in kit-ipd crawler (#99 )	2024-11-04 23:53:48 +01:00
Tim	26e802d88b	Add clickable links to file names in the printed report (#100 ) Co-authored-by: I-Al-Istannen <i-al-istannen@users.noreply.github.com>	2024-11-04 00:32:32 +01:00
I-Al-Istannen	f5c4e82816	Delay ilias loop detection after transform This allows users to filter out duplicated elements and suppress the warning.	2024-11-02 22:46:51 +01:00
I-Al-Istannen	f5273f7ca0	Collapse ilias url crawling into normal page crawling	2024-11-02 22:46:51 +01:00
I-Al-Istannen	fa71a9f44f	Add support for mob videos in page descriptions	2024-10-28 20:35:30 +01:00
I-Al-Istannen	81d6ff53c4	Respect row flex in descriptions	2024-10-28 19:41:03 +01:00
I-Al-Istannen	d7a2b6e019	Delete videos from course descriptions	2024-10-28 19:41:03 +01:00
I-Al-Istannen	71c65e89d1	Internalize images in course descriptions	2024-10-28 19:41:03 +01:00
I-Al-Istannen	c1046498e7	Fix download of links without a target URL They are now downloaded as links to the empty url.	2024-10-28 19:41:03 +01:00
I-Al-Istannen	8fbd1978af	Fix crawling of nested courses	2024-10-28 18:52:27 +01:00
Tim	739dd95850	Use Last-Modified and ETag headers to determine KIT-IPD file versions (#95 ) Co-authored-by: I-Al-Istannen <i-al-istannen@users.noreply.github.com>	2024-10-27 19:03:47 +01:00
I-Al-Istannen	c54c3bcfa1	Fix crawling of favorites	2024-10-27 10:50:59 +01:00
I-Al-Istannen	d7f2229978	Bump version to 3.6.0	2024-10-23 20:17:47 +02:00
I-Al-Istannen	52fdeae752	Crawl custom item groups as folders	2024-10-21 23:43:48 +02:00
I-Al-Istannen	f9bb2e41cf	Sanitize slashes in exercise container names	2024-10-21 22:30:16 +02:00
Mr. Pine	4f9e2ab48d	Support named capture groups in regex transformers (#94 )	2024-10-21 15:21:33 +02:00
I-Al-Istannen	19beb8f07b	Document course overview downloading in config.md	2024-07-31 22:02:43 +02:00
I-Al-Istannen	c897d9e2f5	Support finding entries for course overview page Related to issue #93	2024-06-26 16:54:07 +02:00
Joscha	21a266e302	Update upload-artifact action to v4 https://github.com/actions/upload-artifact/blob/main/docs/MIGRATION.md#multiple-uploads-to-the-same-named-artifact	2024-05-11 16:33:14 +02:00
Pavel Zwerschke	b29b6f93f8	run ci twice Co-authored-by: Garmelon <joscha@plugh.de>	2024-05-11 16:09:46 +02:00
Pavel Zwerschke	318226d7cb	fix bump-version script	2024-05-11 10:27:54 +02:00
Pavel Zwerschke	422cf05f15	Move all configuration into pyproject.toml, add x86 mac to CI	2024-05-11 10:26:19 +02:00
Joscha	819c6673c7	Update changelog	2024-05-10 14:40:25 +02:00
Joscha	89b44c69a7	Update docs All config file options must be documented in CONFIG.md. The README.md is just a starting point. To avoid duplicated info, I've moved most of the docs to CONFIG.md.	2024-05-10 14:36:01 +02:00
Joscha	4b4f72b2ca	Fix command name	2024-05-10 14:34:20 +02:00
Joscha	778517d8c6	Fix KIT crawler requiring base_url and client_id options	2024-05-10 14:12:45 +02:00
Joscha	428b0179fc	Remove IliasConfig Also uses urljoin() in a few places that previously used string concatenation or fstrings. At this point, there isn't yet a need for IliasConfig, so I'd rather keep the code base simpler and more consistent. Should we need a structure like IliasConfig in the future (maybe because we have a few more ilias parsers), it's easy to add back.	2024-05-10 14:09:14 +02:00
Philipp Fruck	ade6309dd9	Update copyright information	2024-05-05 02:34:26 +02:00
Philipp Fruck	fd6cb7b966	docs: Remove some filler words	2024-05-05 02:34:00 +02:00
Philipp Fruck	5c87517ceb	docs: Explain usage with generic ilias	2024-05-04 17:52:12 +02:00
Philipp Fruck	b01f093474	fix: Element detection for other universities Other universities might use other URL schemes for different element types	2024-05-04 17:52:06 +02:00
Philipp Fruck	3a05b90525	fix circular import for _io_repeat	2024-05-04 17:51:59 +02:00
Philipp Fruck	7a00f73e0e	feat: Add authentication to generic ilias dl	2024-05-04 17:51:38 +02:00
Philipp Fruck	5d0621420e	feat: Generic ilias_web command	2024-05-04 17:44:37 +02:00
Philipp Fruck	df98153169	refactor: Extract generic settings from ilias command Preparation for generic ilias_web command	2024-05-04 17:44:30 +02:00
Philipp Fruck	fc1f68ccd9	refactor: Separate generic and KIT ilias functions	2024-05-04 17:44:18 +02:00
I-Al-Istannen	3e831c7e23	Fix normalization of meeting names in cards	2024-04-24 22:32:26 +02:00
Florian Raith	bbcfe9c8dd	Fix typo in CONFIG.md (#89 )	2024-04-19 16:52:18 +02:00