epicyon/content.py

806 lines
28 KiB
Python

__filename__ = "content.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.1.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@freedombone.net"
__status__ = "Production"
import os
import email.parser
from shutil import copyfile
from utils import loadJson
from utils import fileLastModified
from utils import getLinkPrefixes
def htmlReplaceQuoteMarks(content: str) -> str:
"""Replaces quotes with html formatting
"hello" becomes <q>hello</q>
"""
if '"' not in content:
return content
sections = content.split('"')
if len(sections) <= 2:
return content
newContent = ''
openQuote = True
markup = False
for ch in content:
currChar = ch
if ch == '<':
markup = True
elif ch == '>':
markup = False
elif ch == '"' and not markup:
if openQuote:
currChar = '<q>'
else:
currChar = '</q>'
openQuote = not openQuote
newContent += currChar
return newContent
def dangerousMarkup(content: str) -> bool:
"""Returns true if the given content contains dangerous html markup
"""
if '<' not in content:
return False
if '>' not in content:
return False
contentSections = content.split('<')
invalidStrings = ('script', 'canvas', 'style', 'abbr',
'frame', 'iframe', 'html', 'body',
'hr')
for markup in contentSections:
if '>' not in markup:
continue
markup = markup.split('>')[0].strip()
if ' ' not in markup:
for badStr in invalidStrings:
if badStr in markup:
return True
else:
for badStr in invalidStrings:
if badStr + ' ' in markup:
return True
return False
def switchWords(baseDir: str, nickname: str, domain: str, content: str) -> str:
"""Performs word replacements. eg. Trump -> The Orange Menace
"""
switchWordsFilename = baseDir + '/accounts/' + \
nickname + '@' + domain + '/replacewords.txt'
if not os.path.isfile(switchWordsFilename):
return content
with open(switchWordsFilename, 'r') as fp:
for line in fp:
replaceStr = line.replace('\n', '').replace('\r', '')
wordTransform = None
if '->' in replaceStr:
wordTransform = replaceStr.split('->')
elif ':' in replaceStr:
wordTransform = replaceStr.split(':')
elif ',' in replaceStr:
wordTransform = replaceStr.split(',')
elif ';' in replaceStr:
wordTransform = replaceStr.split(';')
elif '-' in replaceStr:
wordTransform = replaceStr.split('-')
if not wordTransform:
continue
if len(wordTransform) == 2:
replaceStr1 = wordTransform[0].strip().replace('"', '')
replaceStr2 = wordTransform[1].strip().replace('"', '')
content = content.replace(replaceStr1, replaceStr2)
return content
def replaceEmojiFromTags(content: str, tag: [], messageType: str) -> str:
"""Uses the tags to replace :emoji: with html image markup
"""
for tagItem in tag:
if not tagItem.get('type'):
continue
if tagItem['type'] != 'Emoji':
continue
if not tagItem.get('name'):
continue
if not tagItem.get('icon'):
continue
if not tagItem['icon'].get('url'):
continue
if '/' not in tagItem['icon']['url']:
continue
if tagItem['name'] not in content:
continue
iconName = tagItem['icon']['url'].split('/')[-1]
if iconName:
if len(iconName) > 1:
if iconName[0].isdigit():
if '.' in iconName:
iconName = iconName.split('.')[0]
# see https://unicode.org/
# emoji/charts/full-emoji-list.html
if '-' not in iconName:
# a single code
try:
replaceChar = chr(int("0x" + iconName, 16))
content = content.replace(tagItem['name'],
replaceChar)
except BaseException:
pass
else:
# sequence of codes
iconCodes = iconName.split('-')
iconCodeSequence = ''
for icode in iconCodes:
try:
iconCodeSequence += chr(int("0x" +
icode, 16))
except BaseException:
iconCodeSequence = ''
break
if iconCodeSequence:
content = content.replace(tagItem['name'],
iconCodeSequence)
htmlClass = 'emoji'
if messageType == 'post header':
htmlClass = 'emojiheader'
if messageType == 'profile':
htmlClass = 'emojiprofile'
emojiHtml = "<img src=\"" + tagItem['icon']['url'] + "\" alt=\"" + \
tagItem['name'].replace(':', '') + \
"\" align=\"middle\" class=\"" + htmlClass + "\"/>"
content = content.replace(tagItem['name'], emojiHtml)
return content
def addMusicTag(content: str, tag: str) -> str:
"""If a music link is found then ensure that the post is
tagged appropriately
"""
if '#' not in tag:
tag = '#'+tag
if tag in content:
return content
musicSites = ('soundcloud.com', 'bandcamp.com')
musicSiteFound = False
for site in musicSites:
if site+'/' in content:
musicSiteFound = True
break
if not musicSiteFound:
return content
return ':music: ' + content + ' ' + tag + ' '
def addWebLinks(content: str) -> str:
"""Adds markup for web links
"""
if ':' not in content:
return content
prefixes = getLinkPrefixes()
# do any of these prefixes exist within the content?
prefixFound = False
for prefix in prefixes:
if prefix in content:
prefixFound = True
break
# if there are no prefixes then just keep the content we have
if not prefixFound:
return content
maxLinkLength = 40
content = content.replace('\r', '')
words = content.replace('\n', ' --linebreak-- ').split(' ')
replaceDict = {}
for w in words:
if ':' not in w:
continue
# does the word begin with a prefix?
prefixFound = False
for prefix in prefixes:
if w.startswith(prefix):
prefixFound = True
break
if not prefixFound:
continue
# the word contains a prefix
if w.endswith('.') or w.endswith(';'):
w = w[:-1]
markup = '<a href="' + w + \
'" rel="nofollow noopener" target="_blank">'
for prefix in prefixes:
if w.startswith(prefix):
markup += '<span class="invisible">' + prefix + '</span>'
break
linkText = w
for prefix in prefixes:
linkText = linkText.replace(prefix, '')
# prevent links from becoming too long
if len(linkText) > maxLinkLength:
markup += '<span class="ellipsis">' + \
linkText[:maxLinkLength] + '</span>'
markup += '<span class="invisible">' + \
linkText[maxLinkLength:] + '</span></a>'
else:
markup += '<span class="ellipsis">' + linkText + '</span></a>'
replaceDict[w] = markup
# do the replacements
for url, markup in replaceDict.items():
content = content.replace(url, markup)
# replace any line breaks
content = content.replace(' --linebreak-- ', '<br>')
return content
def validHashTag(hashtag: str) -> bool:
"""Returns true if the give hashtag contains valid characters
"""
validChars = set('0123456789' +
'abcdefghijklmnopqrstuvwxyz' +
'ABCDEFGHIJKLMNOPQRSTUVWXYZ')
if set(hashtag).issubset(validChars):
return True
return False
def addHashTags(wordStr: str, httpPrefix: str, domain: str,
replaceHashTags: {}, postHashtags: {}) -> bool:
"""Detects hashtags and adds them to the replacements dict
Also updates the hashtags list to be added to the post
"""
if replaceHashTags.get(wordStr):
return True
hashtag = wordStr[1:]
if not validHashTag(hashtag):
return False
hashtagUrl = httpPrefix + "://" + domain + "/tags/" + hashtag
postHashtags[hashtag] = {
'href': hashtagUrl,
'name': '#'+hashtag,
'type': 'Hashtag'
}
replaceHashTags[wordStr] = "<a href=\"" + hashtagUrl + \
"\" class=\"mention hashtag\" rel=\"tag\">#<span>" + \
hashtag + "</span></a>"
return True
def loadEmojiDict(emojiDataFilename: str, emojiDict: {}) -> None:
"""Creates an emoji dictionary based on emoji/emoji-data.txt
"""
if not os.path.isfile(emojiDataFilename):
return
with open(emojiDataFilename, "r") as fileHandler:
for line in fileHandler:
if len(line) < 5:
continue
if line.startswith('#'):
continue
if '; Emoji' not in line:
continue
if ')' not in line:
continue
emojiUnicode = line.split(' ')[0]
if len(emojiUnicode) < 4:
continue
if '..' in emojiUnicode:
emojiUnicode = emojiUnicode.split('..')[0]
emojiName = line.split(')', 1)[1].strip()
emojiName = emojiName.replace('\n', '').replace('\r', '')
emojiName = emojiName.replace(' ', '').replace('-', '')
if '..' in emojiName:
emojiName = emojiName.split('..')[0]
emojiDict[emojiName.lower()] = emojiUnicode
def addEmoji(baseDir: str, wordStr: str,
httpPrefix: str, domain: str,
replaceEmoji: {}, postTags: {},
emojiDict: {}) -> bool:
"""Detects Emoji and adds them to the replacements dict
Also updates the tags list to be added to the post
"""
if not wordStr.startswith(':'):
return False
if not wordStr.endswith(':'):
return False
if len(wordStr) < 3:
return False
if replaceEmoji.get(wordStr):
return True
# remove leading and trailing : characters
emoji = wordStr[1:]
emoji = emoji[:-1]
# is the text of the emoji valid?
if not validHashTag(emoji):
return False
if not emojiDict.get(emoji):
return False
emojiFilename = baseDir + '/emoji/' + emojiDict[emoji] + '.png'
if not os.path.isfile(emojiFilename):
return False
emojiUrl = httpPrefix + "://" + domain + \
"/emoji/" + emojiDict[emoji] + '.png'
postTags[emoji] = {
'icon': {
'mediaType': 'image/png',
'type': 'Image',
'url': emojiUrl
},
'name': ':'+emoji+':',
"updated": fileLastModified(emojiFilename),
"id": emojiUrl.replace('.png', ''),
'type': 'Emoji'
}
return True
def addMention(wordStr: str, httpPrefix: str, following: str,
replaceMentions: {}, recipients: [], tags: {}) -> bool:
"""Detects mentions and adds them to the replacements dict and
recipients list
"""
possibleHandle = wordStr[1:]
# @nick
if following and '@' not in possibleHandle:
# fall back to a best effort match against the following list
# if no domain was specified. eg. @nick
possibleNickname = possibleHandle
for follow in following:
if follow.startswith(possibleNickname + '@'):
replaceDomain = \
follow.replace('\n', '').replace('\r', '').split('@')[1]
recipientActor = httpPrefix + "://" + \
replaceDomain + "/users/" + possibleNickname
if recipientActor not in recipients:
recipients.append(recipientActor)
tags[wordStr] = {
'href': recipientActor,
'name': wordStr,
'type': 'Mention'
}
replaceMentions[wordStr] = \
"<span class=\"h-card\"><a href=\"" + httpPrefix + \
"://" + replaceDomain + "/@" + possibleNickname + \
"\" class=\"u-url mention\">@<span>" + possibleNickname + \
"</span></a></span>"
return True
return False
possibleNickname = None
possibleDomain = None
if '@' not in possibleHandle:
return False
possibleNickname = possibleHandle.split('@')[0]
if not possibleNickname:
return False
possibleDomain = \
possibleHandle.split('@')[1].strip('\n').strip('\r')
if not possibleDomain:
return False
if following:
for follow in following:
if follow.replace('\n', '').replace('\r', '') != possibleHandle:
continue
recipientActor = httpPrefix + "://" + \
possibleDomain + "/users/" + possibleNickname
if recipientActor not in recipients:
recipients.append(recipientActor)
tags[wordStr] = {
'href': recipientActor,
'name': wordStr,
'type': 'Mention'
}
replaceMentions[wordStr] = \
"<span class=\"h-card\"><a href=\"" + httpPrefix + \
"://" + possibleDomain + "/@" + possibleNickname + \
"\" class=\"u-url mention\">@<span>" + possibleNickname + \
"</span></a></span>"
return True
# @nick@domain
if not (possibleDomain == 'localhost' or '.' in possibleDomain):
return False
recipientActor = httpPrefix + "://" + \
possibleDomain + "/users/" + possibleNickname
if recipientActor not in recipients:
recipients.append(recipientActor)
tags[wordStr] = {
'href': recipientActor,
'name': wordStr,
'type': 'Mention'
}
replaceMentions[wordStr] = \
"<span class=\"h-card\"><a href=\"" + httpPrefix + \
"://" + possibleDomain + "/@" + possibleNickname + \
"\" class=\"u-url mention\">@<span>" + possibleNickname + \
"</span></a></span>"
return True
def replaceContentDuplicates(content: str) -> str:
"""Replaces invalid duplicates within content
"""
while '<<' in content:
content = content.replace('<<', '<')
while '>>' in content:
content = content.replace('>>', '>')
content = content.replace('<\\p>', '')
return content
def removeTextFormatting(content: str) -> str:
"""Removes markup for bold, italics, etc
"""
if '<' not in content:
return content
removeMarkup = ('b', 'i', 'ul', 'ol', 'li', 'em', 'strong',
'blockquote', 'h1', 'h2', 'h3', 'h4', 'h5')
for markup in removeMarkup:
content = content.replace('<' + markup + '>', '')
content = content.replace('</' + markup + '>', '')
content = content.replace('<' + markup.upper() + '>', '')
content = content.replace('</' + markup.upper() + '>', '')
return content
def removeHtml(content: str) -> str:
"""Removes html links from the given content.
Used to ensure that profile descriptions don't contain dubious content
"""
if '<' not in content:
return content
removing = False
content = content.replace('<q>', '"').replace('</q>', '"')
result = ''
for ch in content:
if ch == '<':
removing = True
elif ch == '>':
removing = False
elif not removing:
result += ch
return result
def removeLongWords(content: str, maxWordLength: int,
longWordsList: []) -> str:
"""Breaks up long words so that on mobile screens this doesn't
disrupt the layout
"""
content = replaceContentDuplicates(content)
if ' ' not in content:
# handle a single very long string with no spaces
contentStr = content.replace('<p>', '').replace(r'<\p>', '')
if '://' not in contentStr:
if len(contentStr) > maxWordLength:
if '<p>' in content:
content = '<p>' + contentStr[:maxWordLength] + r'<\p>'
else:
content = content[:maxWordLength]
return content
words = content.split(' ')
if not longWordsList:
longWordsList = []
for wordStr in words:
if len(wordStr) > maxWordLength:
if wordStr not in longWordsList:
longWordsList.append(wordStr)
for wordStr in longWordsList:
if wordStr.startswith('<'):
continue
if len(wordStr) == 76:
if wordStr.upper() == wordStr:
# tox address
continue
if '=\"' in wordStr:
continue
if '@' in wordStr:
if '@@' not in wordStr:
continue
if '=.ed25519' in wordStr:
continue
if '.onion' in wordStr:
continue
if '.i2p' in wordStr:
continue
if 'https:' in wordStr:
continue
elif 'http:' in wordStr:
continue
elif 'i2p:' in wordStr:
continue
elif 'gnunet:' in wordStr:
continue
elif 'dat:' in wordStr:
continue
elif 'hyper:' in wordStr:
continue
elif 'briar:' in wordStr:
continue
if '<' in wordStr:
replaceWord = wordStr.split('<', 1)[0]
content = content.replace(wordStr, replaceWord)
wordStr = replaceWord
if '/' in wordStr:
continue
if len(wordStr[maxWordLength:]) < maxWordLength:
content = content.replace(wordStr,
wordStr[:maxWordLength] + '\n' +
wordStr[maxWordLength:])
else:
content = content.replace(wordStr,
wordStr[:maxWordLength])
if content.startswith('<p>'):
if not content.endswith('</p>'):
content = content.strip()+'</p>'
return content
def addHtmlTags(baseDir: str, httpPrefix: str,
nickname: str, domain: str, content: str,
recipients: [], hashtags: {}, isJsonContent=False) -> str:
""" Replaces plaintext mentions such as @nick@domain into html
by matching against known following accounts
"""
if content.startswith('<p>'):
return content
maxWordLength = 40
content = content.replace('\r', '')
content = content.replace('\n', ' --linebreak-- ')
content = addMusicTag(content, 'nowplaying')
words = content.replace(',', ' ').replace(';', ' ').split(' ')
# remove . for words which are not mentions
newWords = []
for wordIndex in range(0, len(words)):
wordStr = words[wordIndex]
if wordStr.endswith('.'):
if not wordStr.startswith('@'):
wordStr = wordStr[:-1]
if wordStr.startswith('.'):
wordStr = wordStr[1:]
newWords.append(wordStr)
words = newWords
replaceMentions = {}
replaceHashTags = {}
replaceEmoji = {}
emojiDict = {}
originalDomain = domain
if ':' in domain:
domain = domain.split(':')[0]
followingFilename = baseDir + '/accounts/' + \
nickname + '@' + domain + '/following.txt'
# read the following list so that we can detect just @nick
# in addition to @nick@domain
following = None
if '@' in words:
if os.path.isfile(followingFilename):
with open(followingFilename, "r") as f:
following = f.readlines()
# extract mentions and tags from words
longWordsList = []
for wordStr in words:
wordLen = len(wordStr)
if wordLen > 2:
if wordLen > maxWordLength:
longWordsList.append(wordStr)
firstChar = wordStr[0]
if firstChar == '@':
if addMention(wordStr, httpPrefix, following,
replaceMentions, recipients, hashtags):
continue
elif firstChar == '#':
if addHashTags(wordStr, httpPrefix, originalDomain,
replaceHashTags, hashtags):
continue
elif ':' in wordStr:
wordStr2 = wordStr.split(':')[1]
# print('TAG: emoji located - '+wordStr)
if not emojiDict:
# emoji.json is generated so that it can be customized and
# the changes will be retained even if default_emoji.json
# is subsequently updated
if not os.path.isfile(baseDir + '/emoji/emoji.json'):
copyfile(baseDir + '/emoji/default_emoji.json',
baseDir + '/emoji/emoji.json')
emojiDict = loadJson(baseDir + '/emoji/emoji.json')
# print('TAG: looking up emoji for :'+wordStr2+':')
addEmoji(baseDir, ':' + wordStr2 + ':', httpPrefix,
originalDomain, replaceEmoji, hashtags,
emojiDict)
# replace words with their html versions
for wordStr, replaceStr in replaceMentions.items():
content = content.replace(wordStr, replaceStr)
for wordStr, replaceStr in replaceHashTags.items():
content = content.replace(wordStr, replaceStr)
if not isJsonContent:
for wordStr, replaceStr in replaceEmoji.items():
content = content.replace(wordStr, replaceStr)
content = addWebLinks(content)
if longWordsList:
content = removeLongWords(content, maxWordLength, longWordsList)
content = content.replace(' --linebreak-- ', '</p><p>')
return '<p>' + htmlReplaceQuoteMarks(content) + '</p>'
def getMentionsFromHtml(htmlText: str,
matchStr="<span class=\"h-card\"><a href=\"") -> []:
"""Extracts mentioned actors from the given html content string
"""
mentions = []
if matchStr not in htmlText:
return mentions
mentionsList = htmlText.split(matchStr)
for mentionStr in mentionsList:
if '"' not in mentionStr:
continue
actorStr = mentionStr.split('"')[0]
if actorStr.startswith('http') or \
actorStr.startswith('gnunet') or \
actorStr.startswith('i2p') or \
actorStr.startswith('hyper') or \
actorStr.startswith('dat:'):
if actorStr not in mentions:
mentions.append(actorStr)
return mentions
def extractMediaInFormPOST(postBytes, boundary, name: str):
"""Extracts the binary encoding for image/video/audio within a http
form POST
Returns the media bytes and the remaining bytes
"""
imageStartBoundary = b'Content-Disposition: form-data; name="' + \
name.encode('utf8', 'ignore') + b'";'
imageStartLocation = postBytes.find(imageStartBoundary)
if imageStartLocation == -1:
return None, postBytes
# bytes after the start boundary appears
mediaBytes = postBytes[imageStartLocation:]
# look for the next boundary
imageEndBoundary = boundary.encode('utf8', 'ignore')
imageEndLocation = mediaBytes.find(imageEndBoundary)
if imageEndLocation == -1:
# no ending boundary
return mediaBytes, postBytes[:imageStartLocation]
# remaining bytes after the end of the image
remainder = mediaBytes[imageEndLocation:]
# remove bytes after the end boundary
mediaBytes = mediaBytes[:imageEndLocation]
# return the media and the before+after bytes
return mediaBytes, postBytes[:imageStartLocation] + remainder
def saveMediaInFormPOST(mediaBytes, debug: bool,
filenameBase=None) -> (str, str):
"""Saves the given media bytes extracted from http form POST
Returns the filename and attachment type
"""
if not mediaBytes:
if debug:
print('DEBUG: No media found within POST')
return None, None
mediaLocation = -1
searchStr = ''
filename = None
# directly search the binary array for the beginning
# of an image
extensionList = {
'png': 'image/png',
'jpeg': 'image/jpeg',
'gif': 'image/gif',
'webp': 'image/webp',
'mp4': 'video/mp4',
'ogv': 'video/ogv',
'mp3': 'audio/mpeg',
'ogg': 'audio/ogg'
}
detectedExtension = None
for extension, contentType in extensionList.items():
searchStr = b'Content-Type: ' + contentType.encode('utf8', 'ignore')
mediaLocation = mediaBytes.find(searchStr)
if mediaLocation > -1:
# image/video/audio binaries
if extension == 'jpeg':
extension = 'jpg'
elif extension == 'mpeg':
extension = 'mp3'
filename = filenameBase + '.' + extension
attachmentMediaType = \
searchStr.decode().split('/')[0].replace('Content-Type: ', '')
detectedExtension = extension
break
if not filename:
return None, None
# locate the beginning of the image, after any
# carriage returns
startPos = mediaLocation + len(searchStr)
for offset in range(1, 8):
if mediaBytes[startPos+offset] != 10:
if mediaBytes[startPos+offset] != 13:
startPos += offset
break
# remove any existing image files with a different format
extensionTypes = ('png', 'jpg', 'jpeg', 'gif', 'webp')
for ex in extensionTypes:
if ex == detectedExtension:
continue
possibleOtherFormat = \
filename.replace('.temp', '').replace('.' +
detectedExtension, '.' +
ex)
if os.path.isfile(possibleOtherFormat):
os.remove(possibleOtherFormat)
fd = open(filename, 'wb')
fd.write(mediaBytes[startPos:])
fd.close()
return filename, attachmentMediaType
def extractTextFieldsInPOST(postBytes, boundary, debug: bool) -> {}:
"""Returns a dictionary containing the text fields of a http form POST
The boundary argument comes from the http header
"""
msg = email.parser.BytesParser().parsebytes(postBytes)
if debug:
print('DEBUG: POST arriving ' +
msg.get_payload(decode=True).decode('utf-8'))
messageFields = msg.get_payload(decode=True)
messageFields = messageFields.decode('utf-8').split(boundary)
fields = {}
# examine each section of the POST, separated by the boundary
for f in messageFields:
if f == '--':
continue
if ' name="' not in f:
continue
postStr = f.split(' name="', 1)[1]
if '"' not in postStr:
continue
postKey = postStr.split('"', 1)[0]
postValueStr = postStr.split('"', 1)[1]
if ';' in postValueStr:
continue
if '\r\n' not in postValueStr:
continue
postLines = postValueStr.split('\r\n')
postValue = ''
if len(postLines) > 2:
for line in range(2, len(postLines)-1):
if line > 2:
postValue += '\n'
postValue += postLines[line]
fields[postKey] = postValue
return fields