make it work

This commit is contained in:
Matthew Hodgson 2016-03-29 03:13:25 +01:00
parent dd4287ca5d
commit 64b4aead15
4 changed files with 80 additions and 57 deletions

View file

@ -56,7 +56,7 @@ As a first cut, let's do #2 and have the receiver hit the API to calculate its o
API
---
GET /_matrix/media/r0/previewUrl?url=http://wherever.com
GET /_matrix/media/r0/preview_url?url=http://wherever.com
200 OK
{
"og:type" : "article"

View file

@ -26,6 +26,7 @@ from twisted.web.client import (
Agent, readBody, FileBodyProducer, PartialDownloadError,
)
from twisted.web.http_headers import Headers
from twisted.web._newclient import ResponseDone
from StringIO import StringIO
@ -266,7 +267,7 @@ class SimpleHttpClient(object):
headers = dict(response.headers.getAllRawHeaders())
if headers['Content-Length'] > max_size:
if 'Content-Length' in headers and headers['Content-Length'] > max_size:
logger.warn("Requested URL is too large > %r bytes" % (self.max_size,))
# XXX: do we want to explicitly drop the connection here somehow? if so, how?
raise # what should we be raising here?

View file

@ -72,6 +72,7 @@ class BaseMediaResource(Resource):
self.store = hs.get_datastore()
self.max_upload_size = hs.config.max_upload_size
self.max_image_pixels = hs.config.max_image_pixels
self.max_spider_size = hs.config.max_spider_size
self.filepaths = filepaths
self.version_string = hs.version_string
self.downloads = {}

View file

@ -12,26 +12,28 @@
# See the License for the specific language governing permissions and
# limitations under the License.
from .base_resource import BaseMediaResource
from synapse.api.errors import Codes
from twisted.web.resource import Resource
from twisted.web.server import NOT_DONE_YET
from twisted.internet import defer
from lxml import html
from synapse.util.stringutils import random_string
from synapse.http.client import SimpleHttpClient
from synapse.http.server import request_handler, respond_with_json_bytes
from synapse.http.server import request_handler, respond_with_json, respond_with_json_bytes
import os
import ujson as json
import logging
logger = logging.getLogger(__name__)
class PreviewUrlResource(Resource):
class PreviewUrlResource(BaseMediaResource):
isLeaf = True
def __init__(self, hs, filepaths):
Resource.__init__(self)
BaseMediaResource.__init__(self, hs, filepaths)
self.client = SimpleHttpClient(hs)
self.filepaths = filepaths
self.max_spider_size = hs.config.max_spider_size
self.server_name = hs.hostname
self.clock = hs.get_clock()
def render_GET(self, request):
self._async_render_GET(request)
@ -40,57 +42,76 @@ class PreviewUrlResource(Resource):
@request_handler
@defer.inlineCallbacks
def _async_render_GET(self, request):
url = request.args.get("url")
try:
# XXX: if get_user_by_req fails, what should we do in an async render?
requester = yield self.auth.get_user_by_req(request)
url = request.args.get("url")[0]
# TODO: keep track of whether there's an ongoing request for this preview
# and block and return their details if there is one.
media_info = self._download_url(url)
media_info = yield self._download_url(url, requester.user)
logger.warn("got media_info of '%s'" % media_info)
if self._is_media(media_info['media_type']):
dims = yield self._generate_local_thumbnails(
media_info.filesystem_id, media_info
)
og = {
"og:description" : media_info.download_name,
"og:image" : "mxc://%s/%s" % (self.server_name, media_info.filesystem_id),
"og:image:type" : media_info['media_type'],
"og:image:width" : dims.width,
"og:image:height" : dims.height,
}
# define our OG response for this media
elif self._is_html(media_info['media_type']):
tree = html.parse(media_info['filename'])
logger.warn(html.tostring(tree))
# suck it up into lxml and define our OG response.
# if we see any URLs in the OG response, then spider them
# (although the client could choose to do this by asking for previews of those URLs to avoid DoSing the server)
# "og:type" : "article"
# "og:url" : "https://twitter.com/matrixdotorg/status/684074366691356672"
# "og:title" : "Matrix on Twitter"
# "og:image" : "https://pbs.twimg.com/profile_images/500400952029888512/yI0qtFi7_400x400.png"
# "og:description" : "Synapse 0.12 is out! Lots of polishing, performance & bugfixes: /sync API, /r0 prefix, fulltext search, 3PID invites https://t.co/5alhXLLEGP"
# "og:site_name" : "Twitter"
og = {}
for tag in tree.xpath("//*/meta[starts-with(@property, 'og:')]"):
og[tag.attrib['property']] = tag.attrib['content']
# TODO: store our OG details in a cache (and expire them when stale)
# TODO: delete the content to stop diskfilling, as we only ever cared about its OG
else:
logger.warn("Failed to find any OG data in %s", url)
og = {}
respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
except:
os.remove(fname)
# XXX: if we don't explicitly respond here, the request never returns.
# isn't this what server.py's wrapper is meant to be doing for us?
respond_with_json(
request,
500,
{
"error": "Internal server error",
"errcode": Codes.UNKNOWN,
},
send_cors=True
)
raise
if self._is_media(media_type):
dims = yield self._generate_local_thumbnails(
media_info.filesystem_id, media_info
)
og = {
"og:description" : media_info.download_name,
"og:image" : "mxc://%s/%s" % (self.server_name, media_info.filesystem_id),
"og:image:type" : media_info.media_type,
"og:image:width" : dims.width,
"og:image:height" : dims.height,
}
# define our OG response for this media
elif self._is_html(media_type):
tree = html.parse(media_info.filename)
# suck it up into lxml and define our OG response.
# if we see any URLs in the OG response, then spider them
# (although the client could choose to do this by asking for previews of those URLs to avoid DoSing the server)
# "og:type" : "article"
# "og:url" : "https://twitter.com/matrixdotorg/status/684074366691356672"
# "og:title" : "Matrix on Twitter"
# "og:image" : "https://pbs.twimg.com/profile_images/500400952029888512/yI0qtFi7_400x400.png"
# "og:description" : "Synapse 0.12 is out! Lots of polishing, performance & bugfixes: /sync API, /r0 prefix, fulltext search, 3PID invites https://t.co/5alhXLLEGP"
# "og:site_name" : "Twitter"
og = {}
for tag in tree.xpath("//*/meta[starts-with(@property, 'og:')]"):
og[tag.attrib['property']] = tag.attrib['content']
# TODO: store our OG details in a cache (and expire them when stale)
# TODO: delete the content to stop diskfilling, as we only ever cared about its OG
respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
def _download_url(url):
requester = yield self.auth.get_user_by_req(request)
@defer.inlineCallbacks
def _download_url(self, url, user):
# XXX: horrible duplication with base_resource's _download_remote_file()
file_id = random_string(24)
@ -99,6 +120,7 @@ class PreviewUrlResource(Resource):
try:
with open(fname, "wb") as f:
logger.warn("Trying to get url '%s'" % url)
length, headers = yield self.client.get_file(
url, output_stream=f, max_size=self.max_spider_size,
)
@ -137,14 +159,14 @@ class PreviewUrlResource(Resource):
time_now_ms=self.clock.time_msec(),
upload_name=download_name,
media_length=length,
user_id=requester.user,
user_id=user,
)
except:
os.remove(fname)
raise
yield ({
defer.returnValue({
"media_type": media_type,
"media_length": length,
"download_name": download_name,
@ -152,14 +174,13 @@ class PreviewUrlResource(Resource):
"filesystem_id": file_id,
"filename": fname,
})
return
def _is_media(content_type):
def _is_media(self, content_type):
if content_type.lower().startswith("image/"):
return True
def _is_html(content_type):
def _is_html(self, content_type):
content_type = content_type.lower()
if (content_type == "text/html" or
if (content_type.startswith("text/html") or
content_type.startswith("application/xhtml")):
return True