# Copyright (C) 2017-2024 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU Affero General Public License version 3, or any later version
# See top-level LICENSE file for more information
import base64
import stat
import textwrap
from typing import Any, Dict, Iterator, List, Optional, Tuple, Union, cast
import chardet
import charset_normalizer
import magic
from django.utils.html import escape, format_html
from django.utils.safestring import mark_safe
from swh.web.config import get_config
from swh.web.utils import (
archive,
browsers_supported_image_mimes,
django_cache,
format_utc_iso_date,
highlightjs,
reverse,
rst_to_html,
)
from swh.web.utils.exc import NotFoundExc, sentry_capture_exception
from swh.web.utils.typing import SnapshotContext
[docs]
@django_cache()
def get_directory_entries(
sha1_git: str,
) -> Tuple[List[Dict[str, Any]], List[Dict[str, Any]]]:
"""Function that retrieves the content of a directory
from the archive.
The directories entries are first sorted in lexicographical order.
Sub-directories and regular files are then extracted.
Args:
sha1_git: sha1_git identifier of the directory
Returns:
A tuple whose first member corresponds to the sub-directories list
and second member the regular files list
Raises:
NotFoundExc if the directory is not found
"""
entries: List[Dict[str, Any]] = list(archive.lookup_directory(sha1_git))
for e in entries:
e["perms"] = stat.filemode(e["perms"])
if e["type"] == "rev":
# modify dir entry name to explicitly show it points to a revision
e["name"] = "%s @ %s" % (e["name"], e["target"][:7])
elif e["type"] == "file":
# remove unused checksums dict to reduce cache size
e.pop("checksums", None)
dirs = [e for e in entries if e["type"] in ("dir", "rev")]
files = [e for e in entries if e["type"] == "file"]
dirs = sorted(dirs, key=lambda d: d["name"])
files = sorted(files, key=lambda f: f["name"])
return dirs, files
[docs]
def get_mimetype_and_encoding_for_content(content: bytes) -> Tuple[str, str]:
"""Function that returns the mime type and the encoding associated to
a content buffer using the magic module under the hood.
Args:
content: a content buffer
Returns:
A tuple (mimetype, encoding), for instance ('text/plain', 'us-ascii'),
associated to the provided content.
"""
m = magic.Magic(mime=True, mime_encoding=True)
mime_encoding = m.from_buffer(content)
mime_type, encoding = mime_encoding.split(";")
encoding = encoding.replace(" charset=", "")
return mime_type, encoding
# maximum authorized content size in bytes for HTML display
# with code highlighting
content_display_max_size = get_config()["content_display_max_size"]
[docs]
def re_encode_content(
mimetype: str, encoding: str, content_data: bytes
) -> Tuple[str, str, bytes]:
"""Try to re-encode textual content if it is not encoded to UTF-8
for proper display in the browse Web UI.
Args:
mimetype: content mimetype as detected by python-magic
encoding: content encoding as detected by python-magic
content_data: raw content bytes
Returns:
A tuple with 3 members: content mimetype, content encoding (possibly updated
after processing), content raw bytes (possibly reencoded to UTF-8)
"""
if mimetype.startswith("text/") and encoding not in ("us-ascii", "utf-8"):
# first check if charset_normalizer detects an encoding with confidence
result = charset_normalizer.detect(content_data)
if result.get("confidence") and cast(float, result["confidence"]) >= 0.9:
encoding = cast(str, result["encoding"])
content_data = content_data.decode(encoding, "replace").encode("utf-8")
# then try to detect encoding with chardet if the above failed
elif (cresult := chardet.detect(content_data)).get("confidence", 0) >= 0.9:
encoding = cast(str, cresult["encoding"])
content_data = content_data.decode(encoding, "replace").encode("utf-8")
elif encoding == "unknown-8bit":
# probably a malformed UTF-8 content, re-encode it
# by replacing invalid chars with a substitution one
content_data = content_data.decode("utf-8", "replace").encode("utf-8")
elif encoding not in ["utf-8", "binary"]:
content_data = content_data.decode(encoding, "replace").encode("utf-8")
elif mimetype.startswith("application/octet-stream"):
# file may detect a text content as binary
# so try to decode it for display
encodings = ["us-ascii", "utf-8"]
encodings += ["iso-8859-%s" % i for i in range(1, 17)]
for enc in encodings:
try:
content_data = content_data.decode(enc).encode("utf-8")
except Exception:
pass
else:
# ensure display in content view
encoding = enc
mimetype = "text/plain"
break
return mimetype, encoding, content_data
[docs]
def request_content(
query_string: str,
max_size: Optional[int] = content_display_max_size,
re_encode: bool = True,
) -> Dict[str, Any]:
"""Function that retrieves a content from the archive.
Raw bytes content is first retrieved, then the content mime type.
If the mime type is not stored in the archive, it will be computed
using Python magic module.
Args:
query_string: a string of the form "[ALGO_HASH:]HASH" where
optional ALGO_HASH can be either ``sha1``, ``sha1_git``,
``sha256``, or ``blake2s256`` (default to ``sha1``) and HASH
the hexadecimal representation of the hash value
max_size: the maximum size for a content to retrieve (default to 1MB,
no size limit if None)
Returns:
A dict filled with content info.
Raises:
NotFoundExc if the content is not found
"""
content_data = archive.lookup_content(query_string)
filetype = None
language = None
# requests to the indexer db may fail so properly handle
# those cases in order to avoid content display errors
try:
filetype = archive.lookup_content_filetype(query_string)
language = archive.lookup_content_language(query_string)
except Exception as exc:
sentry_capture_exception(exc)
mimetype = "unknown"
encoding = "unknown"
if filetype:
mimetype = filetype["mimetype"]
encoding = filetype["encoding"]
if not max_size or content_data["length"] < max_size:
try:
content_raw = archive.lookup_content_raw(query_string)
except Exception as exc:
sentry_capture_exception(exc)
raise NotFoundExc(
"The bytes of the content are currently not available "
"in the archive."
)
else:
content_data["raw_data"] = content_raw["data"]
if not filetype:
mimetype, encoding = get_mimetype_and_encoding_for_content(
content_data["raw_data"]
)
if re_encode:
mimetype, encoding, raw_data = re_encode_content(
mimetype, encoding, content_data["raw_data"]
)
content_data["raw_data"] = raw_data
else:
content_data["raw_data"] = None
content_data["mimetype"] = mimetype
content_data["encoding"] = encoding
if language:
content_data["language"] = language["lang"]
else:
content_data["language"] = "not detected"
return content_data
[docs]
def prepare_content_for_display(
content_data: bytes, mime_type: str, path: Optional[str]
) -> Dict[str, Any]:
"""Function that prepares a content for HTML display.
The function tries to associate a programming language to a
content in order to perform syntax highlighting client-side
using highlightjs. The language is determined using either
the content filename or its mime type.
If the mime type corresponds to an image format supported
by web browsers, the content will be encoded in base64
for displaying the image.
Args:
content_data: raw bytes of the content
mime_type: mime type of the content
path: path of the content including filename
Returns:
A dict containing the content bytes (possibly different from the one
provided as parameter if it is an image) under the key 'content_data
and the corresponding highlightjs language class under the
key 'language'.
"""
language = None
if path:
language = highlightjs.get_hljs_language_from_filename(path.split("/")[-1])
if language is None:
language = highlightjs.get_hljs_language_from_mime_type(mime_type)
if language is None:
language = "plaintext"
processed_content: Union[bytes, str] = content_data
if mime_type.startswith("image/"):
if mime_type in browsers_supported_image_mimes:
processed_content = base64.b64encode(content_data).decode("ascii")
if mime_type.startswith("image/svg"):
mime_type = "image/svg+xml"
if mime_type.startswith("text/") or mime_type.startswith("application/"):
processed_content = content_data.decode("utf-8", errors="replace")
return {
"content_data": processed_content,
"language": language,
"mimetype": mime_type,
}
[docs]
def gen_link(
url: str,
link_text: Optional[str] = None,
link_attrs: Optional[Dict[str, str]] = None,
) -> str:
"""
Utility function for generating an HTML link to insert
in Django templates.
Args:
url: an url
link_text: optional text for the produced link,
if not provided the url will be used
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form '<a href="url">link_text</a>'
"""
attrs = " "
if link_attrs:
for k, v in link_attrs.items():
if k != escape(k):
raise ValueError("weird attribute passed to gen_link")
attrs += '%s="%s" ' % (k, escape(v))
if not link_text:
link_text = url
return format_html(
'<a{attrs}href="{url}">{link_text}</a>',
attrs=mark_safe(attrs),
url=url,
link_text=link_text,
)
def _snapshot_context_query_params(
snapshot_context: Optional[SnapshotContext],
) -> Dict[str, str]:
query_params: Dict[str, str] = {}
if not snapshot_context:
return query_params
if snapshot_context and snapshot_context["origin_info"]:
origin_info = snapshot_context["origin_info"]
snp_query_params = snapshot_context["query_params"]
query_params = {"origin_url": origin_info["url"]}
if "timestamp" in snp_query_params:
query_params["timestamp"] = str(snp_query_params["timestamp"])
if "visit_id" in snp_query_params:
query_params["visit_id"] = str(snp_query_params["visit_id"])
if "snapshot" in snp_query_params and "visit_id" not in query_params:
query_params["snapshot"] = str(snp_query_params["snapshot"])
elif snapshot_context:
query_params = {"snapshot": snapshot_context["snapshot_id"]}
if snapshot_context["release"]:
query_params["release"] = snapshot_context["release"]
elif snapshot_context["branch"] and snapshot_context["branch"] not in (
"HEAD",
snapshot_context["revision_id"],
):
query_params["branch"] = snapshot_context["branch"]
elif snapshot_context["revision_id"]:
query_params["revision"] = snapshot_context["revision_id"]
return query_params
[docs]
def gen_revision_url(
revision_id: str, snapshot_context: Optional[SnapshotContext] = None
) -> str:
"""
Utility function for generating an url to a revision.
Args:
revision_id: a revision id
snapshot_context: if provided, generate snapshot-dependent
browsing url
Returns:
str: The url to browse the revision
"""
query_params = _snapshot_context_query_params(snapshot_context)
# remove query parameters not needed for a revision view
query_params.pop("revision", None)
query_params.pop("release", None)
return reverse(
"browse-revision", url_args={"sha1_git": revision_id}, query_params=query_params
)
[docs]
def gen_revision_link(
revision_id: str,
shorten_id: bool = False,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> Optional[str]:
"""
Utility function for generating a link to a revision HTML view
to insert in Django templates.
Args:
revision_id: a revision id
shorten_id: whether to shorten the revision id to 7
characters for the link text
snapshot_context: if provided, generate snapshot-dependent
browsing link
link_text: optional text for the generated link
(the revision id will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
str: An HTML link in the form '<a href="revision_url">revision_id</a>'
"""
if not revision_id:
return None
revision_url = gen_revision_url(revision_id, snapshot_context)
if shorten_id:
return gen_link(revision_url, revision_id[:7], link_attrs)
else:
if not link_text:
link_text = revision_id
return gen_link(revision_url, link_text, link_attrs)
[docs]
def gen_directory_link(
sha1_git: str,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> Optional[str]:
"""
Utility function for generating a link to a directory HTML view
to insert in Django templates.
Args:
sha1_git: directory identifier
link_text: optional text for the generated link
(the directory id will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form '<a href="directory_view_url">link_text</a>'
"""
if not sha1_git:
return None
query_params = _snapshot_context_query_params(snapshot_context)
directory_url = reverse(
"browse-directory", url_args={"sha1_git": sha1_git}, query_params=query_params
)
if not link_text:
link_text = sha1_git
return gen_link(directory_url, link_text, link_attrs)
[docs]
def gen_snapshot_link(
snapshot_id: str,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> str:
"""
Utility function for generating a link to a snapshot HTML view
to insert in Django templates.
Args:
snapshot_id: snapshot identifier
link_text: optional text for the generated link
(the snapshot id will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form '<a href="snapshot_view_url">link_text</a>'
"""
query_params = _snapshot_context_query_params(snapshot_context)
snapshot_url = reverse(
"browse-snapshot",
url_args={"snapshot_id": snapshot_id},
query_params=query_params,
)
if not link_text:
link_text = snapshot_id
return gen_link(snapshot_url, link_text, link_attrs)
[docs]
def gen_content_link(
sha1_git: str,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> Optional[str]:
"""
Utility function for generating a link to a content HTML view
to insert in Django templates.
Args:
sha1_git: content identifier
link_text: optional text for the generated link
(the content sha1_git will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form '<a href="content_view_url">link_text</a>'
"""
if not sha1_git:
return None
query_params = _snapshot_context_query_params(snapshot_context)
content_url = reverse(
"browse-content",
url_args={"query_string": "sha1_git:" + sha1_git},
query_params=query_params,
)
if not link_text:
link_text = sha1_git
return gen_link(content_url, link_text, link_attrs)
[docs]
def get_revision_log_url(
revision_id: str, snapshot_context: Optional[SnapshotContext] = None
) -> str:
"""
Utility function for getting the URL for a revision log HTML view
(possibly in the context of an origin).
Args:
revision_id: revision identifier the history heads to
snapshot_context: if provided, generate snapshot-dependent
browsing link
Returns:
The revision log view URL
"""
query_params = {}
if snapshot_context:
query_params = _snapshot_context_query_params(snapshot_context)
query_params["revision"] = revision_id
if snapshot_context and snapshot_context["origin_info"]:
revision_log_url = reverse("browse-origin-log", query_params=query_params)
elif snapshot_context:
url_args = {"snapshot_id": snapshot_context["snapshot_id"]}
del query_params["snapshot"]
revision_log_url = reverse(
"browse-snapshot-log", url_args=url_args, query_params=query_params
)
else:
revision_log_url = reverse(
"browse-revision-log", url_args={"sha1_git": revision_id}
)
return revision_log_url
[docs]
def gen_revision_log_link(
revision_id: str,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> Optional[str]:
"""
Utility function for generating a link to a revision log HTML view
(possibly in the context of an origin) to insert in Django templates.
Args:
revision_id: revision identifier the history heads to
snapshot_context: if provided, generate snapshot-dependent
browsing link
link_text: optional text to use for the generated link
(the revision id will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form
'<a href="revision_log_view_url">link_text</a>'
"""
if not revision_id:
return None
revision_log_url = get_revision_log_url(revision_id, snapshot_context)
if not link_text:
link_text = revision_id
return gen_link(revision_log_url, link_text, link_attrs)
[docs]
def gen_person_mail_link(
person: Dict[str, Any], link_text: Optional[str] = None
) -> str:
"""
Utility function for generating a mail link to a person to insert
in Django templates.
Args:
person: dictionary containing person data
(*name*, *email*, *fullname*)
link_text: optional text to use for the generated mail link
(the person name will be used by default)
Returns:
str: A mail link to the person or the person name if no email is
present in person data
"""
person_name = person["name"] or person["fullname"] or "None"
if link_text is None:
link_text = person_name
person_email = person["email"] if person["email"] else None
if person_email is None and "@" in person_name and " " not in person_name:
person_email = person_name
if person_email:
return gen_link(url="mailto:%s" % person_email, link_text=link_text)
else:
return person_name
[docs]
def gen_release_link(
sha1_git: str,
snapshot_context: Optional[SnapshotContext] = None,
link_text: Optional[str] = "Browse",
link_attrs: Optional[Dict[str, str]] = {
"class": "btn btn-secondary btn-sm",
"role": "button",
},
) -> str:
"""
Utility function for generating a link to a release HTML view
to insert in Django templates.
Args:
sha1_git: release identifier
link_text: optional text for the generated link
(the release id will be used by default)
link_attrs: optional attributes (e.g. class)
to add to the link
Returns:
An HTML link in the form '<a href="release_view_url">link_text</a>'
"""
query_params = _snapshot_context_query_params(snapshot_context)
release_url = reverse(
"browse-release", url_args={"sha1_git": sha1_git}, query_params=query_params
)
if not link_text:
link_text = sha1_git
return gen_link(release_url, link_text, link_attrs)
# list of common readme names ordered by preference
# (lower indices have higher priority)
_common_readme_names = [
"readme.markdown",
"readme.md",
"readme.rst",
"readme.txt",
"readme",
]
[docs]
def get_readme_to_display(
readmes: Dict[str, str]
) -> Tuple[Optional[str], Optional[str], Optional[str]]:
"""
Process a list of readme files found in a directory
in order to find the adequate one to display.
Args:
readmes: a dict where keys are readme file names and values
are readme sha1_gits
Returns:
A tuple (readme_name, readme_url, readme_html)
"""
readme_name = None
readme_url = None
readme_sha1_git = None
readme_html = None
lc_readmes = {
k.lower(): {"orig_name": k, "sha1_git": v} for k, v in readmes.items()
}
# look for readme names according to the preference order
# defined by the _common_readme_names list
for common_readme_name in _common_readme_names:
if common_readme_name in lc_readmes:
readme_name = lc_readmes[common_readme_name]["orig_name"]
readme_sha1_git = lc_readmes[common_readme_name]["sha1_git"]
readme_url = (
reverse(
"browse-content-raw",
url_args={"query_string": f"sha1_git:{readme_sha1_git}"},
query_params={"re_encode": "true"},
)
if readme_sha1_git is not None
else None
)
break
# otherwise pick the first readme like file if any
if not readme_name and len(readmes.items()) > 0:
readme_name = next(iter(readmes))
readme_sha1_git = readmes[readme_name]
readme_url = (
reverse(
"browse-content-raw",
url_args={"query_string": f"sha1_git:{readme_sha1_git}"},
query_params={"re_encode": "true"},
)
if readme_sha1_git is not None
else None
)
# convert rst README to html server side as there is
# no viable solution to perform that task client side
if readme_name and readme_name.endswith(".rst"):
@django_cache(
catch_exception=True,
exception_return_value="Readme bytes are not available",
)
def _rst_readme_to_html(readme_sha1_git):
rst_doc = request_content(f"sha1_git:{readme_sha1_git}")
return rst_to_html(rst_doc["raw_data"].decode("utf-8", errors="replace"))
readme_html = _rst_readme_to_html(readme_sha1_git)
elif readme_sha1_git:
# check content exists in the archive
if not archive.lookup_hash(f"sha1_git:{readme_sha1_git}")["found"]:
readme_url = None
return readme_name, readme_url, readme_html
