diff options
| -rw-r--r-- | changelog.d/12219.misc | 1 | ||||
| -rw-r--r-- | synapse/rest/media/v1/preview_html.py | 39 | ||||
| -rw-r--r-- | synapse/rest/media/v1/preview_url_resource.py | 23 | ||||
| -rw-r--r-- | tests/rest/media/v1/test_html_preview.py | 54 |
4 files changed, 26 insertions, 91 deletions
diff --git a/changelog.d/12219.misc b/changelog.d/12219.misc new file mode 100644 index 0000000000..6079414092 --- /dev/null +++ b/changelog.d/12219.misc @@ -0,0 +1 @@ +Clean-up logic around rebasing URLs for URL image previews. diff --git a/synapse/rest/media/v1/preview_html.py b/synapse/rest/media/v1/preview_html.py index 872a9e72e8..4cc9c66fbe 100644 --- a/synapse/rest/media/v1/preview_html.py +++ b/synapse/rest/media/v1/preview_html.py @@ -16,7 +16,6 @@ import itertools import logging import re from typing import TYPE_CHECKING, Dict, Generator, Iterable, Optional, Set, Union -from urllib import parse as urlparse if TYPE_CHECKING: from lxml import etree @@ -144,9 +143,7 @@ def decode_body( return etree.fromstring(body, parser) -def parse_html_to_open_graph( - tree: "etree.Element", media_uri: str -) -> Dict[str, Optional[str]]: +def parse_html_to_open_graph(tree: "etree.Element") -> Dict[str, Optional[str]]: """ Parse the HTML document into an Open Graph response. @@ -155,7 +152,6 @@ def parse_html_to_open_graph( Args: tree: The parsed HTML document. - media_url: The URI used to download the body. Returns: The Open Graph response as a dictionary. @@ -209,7 +205,7 @@ def parse_html_to_open_graph( "//*/meta[translate(@itemprop, 'IMAGE', 'image')='image']/@content" ) if meta_image: - og["og:image"] = rebase_url(meta_image[0], media_uri) + og["og:image"] = meta_image[0] else: # TODO: consider inlined CSS styles as well as width & height attribs images = tree.xpath("//img[@src][number(@width)>10][number(@height)>10]") @@ -320,37 +316,6 @@ def _iterate_over_text( ) -def rebase_url(url: str, base: str) -> str: - """ - Resolves a potentially relative `url` against an absolute `base` URL. - - For example: - - >>> rebase_url("subpage", "https://example.com/foo/") - 'https://example.com/foo/subpage' - >>> rebase_url("sibling", "https://example.com/foo") - 'https://example.com/sibling' - >>> rebase_url("/bar", "https://example.com/foo/") - 'https://example.com/bar' - >>> rebase_url("https://alice.com/a/", "https://example.com/foo/") - 'https://alice.com/a' - """ - base_parts = urlparse.urlparse(base) - # Convert the parsed URL to a list for (potential) modification. - url_parts = list(urlparse.urlparse(url)) - # Add a scheme, if one does not exist. - if not url_parts[0]: - url_parts[0] = base_parts.scheme or "http" - # Fix up the hostname, if this is not a data URL. - if url_parts[0] != "data" and not url_parts[1]: - url_parts[1] = base_parts.netloc - # If the path does not start with a /, nest it under the base path's last - # directory. - if not url_parts[2].startswith("/"): - url_parts[2] = re.sub(r"/[^/]+$", "/", base_parts.path) + url_parts[2] - return urlparse.urlunparse(url_parts) - - def summarize_paragraphs( text_nodes: Iterable[str], min_size: int = 200, max_size: int = 500 ) -> Optional[str]: diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py index 14ea88b240..d47af8ead6 100644 --- a/synapse/rest/media/v1/preview_url_resource.py +++ b/synapse/rest/media/v1/preview_url_resource.py @@ -22,7 +22,7 @@ import shutil import sys import traceback from typing import TYPE_CHECKING, BinaryIO, Iterable, Optional, Tuple -from urllib import parse as urlparse +from urllib.parse import urljoin, urlparse, urlsplit from urllib.request import urlopen import attr @@ -44,11 +44,7 @@ from synapse.metrics.background_process_metrics import run_as_background_process from synapse.rest.media.v1._base import get_filename_from_headers from synapse.rest.media.v1.media_storage import MediaStorage from synapse.rest.media.v1.oembed import OEmbedProvider -from synapse.rest.media.v1.preview_html import ( - decode_body, - parse_html_to_open_graph, - rebase_url, -) +from synapse.rest.media.v1.preview_html import decode_body, parse_html_to_open_graph from synapse.types import JsonDict, UserID from synapse.util import json_encoder from synapse.util.async_helpers import ObservableDeferred @@ -187,7 +183,7 @@ class PreviewUrlResource(DirectServeJsonResource): ts = self.clock.time_msec() # XXX: we could move this into _do_preview if we wanted. - url_tuple = urlparse.urlsplit(url) + url_tuple = urlsplit(url) for entry in self.url_preview_url_blacklist: match = True for attrib in entry: @@ -322,7 +318,7 @@ class PreviewUrlResource(DirectServeJsonResource): # Parse Open Graph information from the HTML in case the oEmbed # response failed or is incomplete. - og_from_html = parse_html_to_open_graph(tree, media_info.uri) + og_from_html = parse_html_to_open_graph(tree) # Compile the Open Graph response by using the scraped # information from the HTML and overlaying any information @@ -588,12 +584,17 @@ class PreviewUrlResource(DirectServeJsonResource): if "og:image" not in og or not og["og:image"]: return + # The image URL from the HTML might be relative to the previewed page, + # convert it to an URL which can be requested directly. + image_url = og["og:image"] + url_parts = urlparse(image_url) + if url_parts.scheme != "data": + image_url = urljoin(media_info.uri, image_url) + # FIXME: it might be cleaner to use the same flow as the main /preview_url # request itself and benefit from the same caching etc. But for now we # just rely on the caching on the master request to speed things up. - image_info = await self._handle_url( - rebase_url(og["og:image"], media_info.uri), user, allow_data_urls=True - ) + image_info = await self._handle_url(image_url, user, allow_data_urls=True) if _is_media(image_info.media_type): # TODO: make sure we don't choke on white-on-transparent images diff --git a/tests/rest/media/v1/test_html_preview.py b/tests/rest/media/v1/test_html_preview.py index 3fb37a2a59..62e308814d 100644 --- a/tests/rest/media/v1/test_html_preview.py +++ b/tests/rest/media/v1/test_html_preview.py @@ -16,7 +16,6 @@ from synapse.rest.media.v1.preview_html import ( _get_html_media_encodings, decode_body, parse_html_to_open_graph, - rebase_url, summarize_paragraphs, ) @@ -161,7 +160,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Foo", "og:description": "Some text."}) @@ -177,7 +176,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Foo", "og:description": "Some text."}) @@ -196,7 +195,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual( og, @@ -218,7 +217,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Foo", "og:description": "Some text."}) @@ -232,7 +231,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": None, "og:description": "Some text."}) @@ -247,7 +246,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Title", "og:description": "Some text."}) @@ -262,7 +261,7 @@ class CalcOgTestCase(unittest.TestCase): """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": None, "og:description": "Some text."}) @@ -290,7 +289,7 @@ class CalcOgTestCase(unittest.TestCase): <head><title>Foo</title></head><body>Some text.</body></html> """.strip() tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Foo", "og:description": "Some text."}) def test_invalid_encoding(self) -> None: @@ -304,7 +303,7 @@ class CalcOgTestCase(unittest.TestCase): </html> """ tree = decode_body(html, "http://example.com/test.html", "invalid-encoding") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "Foo", "og:description": "Some text."}) def test_invalid_encoding2(self) -> None: @@ -319,7 +318,7 @@ class CalcOgTestCase(unittest.TestCase): </html> """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "ÿÿ Foo", "og:description": "Some text."}) def test_windows_1252(self) -> None: @@ -333,7 +332,7 @@ class CalcOgTestCase(unittest.TestCase): </html> """ tree = decode_body(html, "http://example.com/test.html") - og = parse_html_to_open_graph(tree, "http://example.com/test.html") + og = parse_html_to_open_graph(tree) self.assertEqual(og, {"og:title": "ó", "og:description": "Some text."}) @@ -448,34 +447,3 @@ class MediaEncodingTestCase(unittest.TestCase): 'text/html; charset="invalid"', ) self.assertEqual(list(encodings), ["utf-8", "cp1252"]) - - -class RebaseUrlTestCase(unittest.TestCase): - def test_relative(self) -> None: - """Relative URLs should be resolved based on the context of the base URL.""" - self.assertEqual( - rebase_url("subpage", "https://example.com/foo/"), - "https://example.com/foo/subpage", - ) - self.assertEqual( - rebase_url("sibling", "https://example.com/foo"), - "https://example.com/sibling", - ) - self.assertEqual( - rebase_url("/bar", "https://example.com/foo/"), - "https://example.com/bar", - ) - - def test_absolute(self) -> None: - """Absolute URLs should not be modified.""" - self.assertEqual( - rebase_url("https://alice.com/a/", "https://example.com/foo/"), - "https://alice.com/a/", - ) - - def test_data(self) -> None: - """Data URLs should not be modified.""" - self.assertEqual( - rebase_url("data:,Hello%2C%20World%21", "https://example.com/foo/"), - "data:,Hello%2C%20World%21", - ) |