overleaf/services/web/config/settings.defaults.coffee

Path = require('path')
http = require('http')
http.globalAgent.maxSockets = 300

# Make time interval config easier.
seconds = 1000
minutes = 60 * seconds

# These credentials are used for authenticating api requests
# between services that may need to go over public channels
httpAuthUser = process.env['WEB_API_USER']
httpAuthPass = process.env['WEB_API_PASSWORD']
httpAuthUsers = {}
if httpAuthUser and httpAuthPass
	httpAuthUsers[httpAuthUser] = httpAuthPass

sessionSecret = process.env['SESSION_SECRET'] or "secret-please-change"

if process.env['V1_API_URL'] or process.env['V1_HOST']
	v1Api =
		url: process.env['V1_API_URL'] or "http://#{process.env['V1_HOST']}:5000"
		user: process.env['V1_API_USER']
		pass: process.env['V1_API_PASSWORD']
else
	v1Api =
		url: undefined
		user: undefined
		pass: undefined

intFromEnv = (name, defaultValue) ->
	if defaultValue in [null, undefined] or typeof defaultValue != 'number'
		throw new Error("Bad default integer value for setting: #{name}, #{defaultValue}")
	parseInt(process.env[name], 10) || defaultValue

module.exports = settings =

	allowAnonymousReadAndWriteSharing:
		process.env['SHARELATEX_ALLOW_ANONYMOUS_READ_AND_WRITE_SHARING'] == 'true'


	# Databases
	# ---------
	mongo:
		url : process.env['MONGO_CONNECTION_STRING'] || process.env['MONGO_URL'] || "mongodb://#{process.env['MONGO_HOST'] or '127.0.0.1'}/sharelatex"
		poolSize: parseInt(process.env['MONGO_POOL_SIZE'], 10) || 10

	redis:
		web:
			host: process.env['REDIS_HOST'] || "localhost"
			port: process.env['REDIS_PORT'] || "6379"
			password: process.env["REDIS_PASSWORD"] or ""
			maxRetriesPerRequest: parseInt(process.env["REDIS_MAX_RETRIES_PER_REQUEST"] || '20')

		# websessions:
		# 	cluster: [
		# 		{host: 'localhost', port: 7000}
		# 		{host: 'localhost', port: 7001}
		# 		{host: 'localhost', port: 7002}
		# 		{host: 'localhost', port: 7003}
		# 		{host: 'localhost', port: 7004}
		# 		{host: 'localhost', port: 7005}
		# 	]

		# ratelimiter:
		# 	cluster: [
		# 		{host: 'localhost', port: 7000}
		# 		{host: 'localhost', port: 7001}
		# 		{host: 'localhost', port: 7002}
		# 		{host: 'localhost', port: 7003}
		# 		{host: 'localhost', port: 7004}
		# 		{host: 'localhost', port: 7005}
		# 	]

		# cooldown:
		# 	cluster: [
		# 		{host: 'localhost', port: 7000}
		# 		{host: 'localhost', port: 7001}
		# 		{host: 'localhost', port: 7002}
		# 		{host: 'localhost', port: 7003}
		# 		{host: 'localhost', port: 7004}
		# 		{host: 'localhost', port: 7005}
		# 	]

		api:
			host: process.env['REDIS_HOST'] || "localhost"
			port: process.env['REDIS_PORT'] || "6379"
			password: process.env["REDIS_PASSWORD"] or ""
			maxRetriesPerRequest: parseInt(process.env["REDIS_MAX_RETRIES_PER_REQUEST"] || '20')

	# Service locations
	# -----------------

	# Configure which ports to run each service on. Generally you
	# can leave these as they are unless you have some other services
	# running which conflict, or want to run the web process on port 80.
	internal:
		web:
			port: webPort = process.env['WEB_PORT'] or 3000
			host: process.env['LISTEN_ADDRESS'] or 'localhost'
		documentupdater:
			port: docUpdaterPort = 3003

	gitBridgePublicBaseUrl: "http://#{process.env['GIT_BRIDGE_HOST'] || 'localhost'}:8000"

	# Tell each service where to find the other services. If everything
	# is running locally then this is easy, but they exist as separate config
	# options incase you want to run some services on remote hosts.
	apis:
		web:
			url: "http://#{process.env['WEB_API_HOST'] or process.env['WEB_HOST'] or "localhost"}:#{process.env['WEB_API_PORT'] or process.env['WEB_PORT'] or 3000}"
			user: httpAuthUser
			pass: httpAuthPass
		documentupdater:
			url : "http://#{process.env['DOCUPDATER_HOST'] or process.env['DOCUMENT_UPDATER_HOST'] or 'localhost'}:#{docUpdaterPort}"
		thirdPartyDataStore:
			url : "http://#{process.env['TPDS_HOST'] or 'localhost'}:3002"
			emptyProjectFlushDelayMiliseconds: 5 * seconds
			dropboxApp: process.env['TPDS_DROPBOX_APP']
		tags:
			url :"http://#{process.env['TAGS_HOST'] or 'localhost'}:3012"
		spelling:
			url : "http://#{process.env['SPELLING_HOST'] or 'localhost'}:3005"
			host: process.env['SPELLING_HOST']
		trackchanges:
			url : "http://#{process.env['TRACK_CHANGES_HOST'] or 'localhost'}:3015"
		project_history:
			sendProjectStructureOps: process.env.PROJECT_HISTORY_ENABLED == 'true' or false
			initializeHistoryForNewProjects: process.env.PROJECT_HISTORY_ENABLED == 'true' or false
			displayHistoryForNewProjects: process.env.PROJECT_HISTORY_ENABLED == 'true' or false
			url : "http://#{process.env['PROJECT_HISTORY_HOST'] or 'localhost'}:3054"
		docstore:
			url : "http://#{process.env['DOCSTORE_HOST'] or 'localhost'}:3016"
			pubUrl: "http://#{process.env['DOCSTORE_HOST'] or 'localhost'}:3016"
		chat:
			url: "http://#{process.env['CHAT_HOST'] or 'localhost'}:3010"
			internal_url: "http://#{process.env['CHAT_HOST'] or 'localhost'}:3010"
		blog:
			url: "http://localhost:3008"
			port: 3008
		university:
			url: "http://localhost:3011"
		filestore:
			url: "http://#{process.env['FILESTORE_HOST'] or 'localhost'}:3009"
		clsi:
			url: "http://#{process.env['CLSI_HOST'] or 'localhost'}:3013"
			# url: "http://#{process.env['CLSI_LB_HOST']}:3014"
			backendGroupName: undefined
		templates:
			url: "http://#{process.env['TEMPLATES_HOST'] or 'localhost'}:3007"
		githubSync:
			url: "http://#{process.env['GITHUB_SYNC_HOST'] or 'localhost'}:3022"
		recurly:
			apiKey: process.env['RECURLY_API_KEY'] or ''
			apiVersion: process.env['RECURLY_API_VERSION']
			subdomain: process.env['RECURLY_SUBDOMAIN'] or ''
			publicKey: process.env['RECURLY_PUBLIC_KEY'] or ''
		geoIpLookup:
			url: "http://#{process.env['GEOIP_HOST'] or process.env['FREEGEOIP_HOST'] or  'localhost'}:8080/json/"
		realTime:
			url: "http://#{process.env['REALTIME_HOST'] or 'localhost'}:3026"
		contacts:
			url: "http://#{process.env['CONTACTS_HOST'] or 'localhost'}:3036"
		sixpack:
			url: ""
		references:
			url: if process.env['REFERENCES_HOST']? then "http://#{process.env['REFERENCES_HOST']}:3040" else undefined
		notifications:
			url: "http://#{process.env['NOTIFICATIONS_HOST'] or 'localhost'}:3042"
		analytics:
			url: "http://#{process.env['ANALYTICS_HOST'] or 'localhost'}:3050"
		linkedUrlProxy:
			url: process.env['LINKED_URL_PROXY']
		thirdpartyreferences:
			url: "http://#{process.env['THIRD_PARTY_REFERENCES_HOST'] or 'localhost'}:3046"
		v1:
			url: v1Api.url
			user: v1Api.user
			pass: v1Api.pass
		v1_history:
			url: "http://#{process.env['V1_HISTORY_HOST'] or "localhost"}:3100/api"
			user: process.env['V1_HISTORY_USER'] or 'staging'
			pass: process.env['V1_HISTORY_PASSWORD'] or 'password'

	templates:
		user_id: process.env.TEMPLATES_USER_ID or "5395eb7aad1f29a88756c7f2"
		showSocialButtons: false
		showComments: false

	# cdn:
	# 	web:
	# 		host:"http://nowhere.sharelatex.dev"
	#		darkHost:"http://cdn.sharelatex.dev:3000"

	# Where your instance of ShareLaTeX can be found publically. Used in emails
	# that are sent out, generated links, etc.
	siteUrl : siteUrl = process.env['PUBLIC_URL'] or 'http://localhost:3000'

	lockManager:
		lockTestInterval: intFromEnv('LOCK_MANAGER_LOCK_TEST_INTERVAL', 50)
		maxTestInterval: intFromEnv('LOCK_MANAGER_MAX_TEST_INTERVAL', 1000)
		maxLockWaitTime: intFromEnv('LOCK_MANAGER_MAX_LOCK_WAIT_TIME', 10000)
		redisLockExpiry: intFromEnv('LOCK_MANAGER_REDIS_LOCK_EXPIRY', 30)
		slowExecutionThreshold: intFromEnv('LOCK_MANAGER_SLOW_EXECUTION_THRESHOLD', 5000)

	# Used to close the editor off to users
	editorIsOpen: process.env['EDITOR_IS_OPEN'] or true
	
	# Optional separate location for websocket connections, if unset defaults to siteUrl.
	wsUrl: process.env['WEBSOCKET_URL']
	wsUrlV2: process.env['WEBSOCKET_URL_V2']
	wsUrlBeta: process.env['WEBSOCKET_URL_BETA']

	wsUrlV2Percentage: parseInt(process.env['WEBSOCKET_URL_V2_PERCENTAGE'] || '0', 10)

	# cookie domain
	# use full domain for cookies to only be accessible from that domain,
	# replace subdomain with dot to have them accessible on all subdomains
	cookieDomain: process.env['COOKIE_DOMAIN']
	cookieName: process.env['COOKIE_NAME'] or "sharelatex.sid"

	# this is only used if cookies are used for clsi backend
	#clsiCookieKey: "clsiserver"

	# Same, but with http auth credentials.
	httpAuthSiteUrl: "http://#{httpAuthUser}:#{httpAuthPass}@#{siteUrl}"

	robotsNoindex: (process.env['ROBOTS_NOINDEX'] == "true") or false

	maxEntitiesPerProject: 2000
	
	maxUploadSize: 50 * 1024 * 1024 # 50 MB

	# Security
	# --------
	security:
		sessionSecret: sessionSecret
		bcryptRounds: (parseInt(process.env['BCRYPT_ROUNDS'], 10) || 12) # number of rounds used to hash user passwords (raised to power 2)

	httpAuthUsers: httpAuthUsers

	twoFactorAuthentication:
		enabled: process.env['TWO_FACTOR_AUTHENTICATION_ENABLED'] == 'true'
		requiredForStaff: process.env['TWO_FACTOR_AUTHENTICATION_REQUIRED_FOR_STAFF'] == 'true'

	# Default features
	# ----------------
	#
	# You can select the features that are enabled by default for new
	# new users.
	defaultFeatures: defaultFeatures =
		collaborators: -1
		dropbox: true
		github: true
		gitBridge: true
		versioning: true
		compileTimeout: 180
		compileGroup: "standard"
		references: true
		templates: true
		trackChanges: true

	features:
		personal: defaultFeatures

	plans: plans = [{
		planCode: "personal"
		name: "Personal"
		price: 0
		features: defaultFeatures
	}]

	enableSubscriptions:false

	enabledLinkedFileTypes: (process.env['ENABLED_LINKED_FILE_TYPES'] or '').split(',')

	# i18n
	# ------
	#
	i18n:
		subdomainLang:
			www: {lngCode:"en", url: siteUrl}
		defaultLng: "en"

	# Spelling languages
	# ------------------
	#
	# You must have the corresponding aspell package installed to
	# be able to use a language.
	languages: [
		{code: "en", name: "English"},
		{code: "en_US", name: "English (American)"},
		{code: "en_GB", name: "English (British)"},
		{code: "en_CA", name: "English (Canadian)"},
		{code: "af", name: "Afrikaans"},
		{code: "ar", name: "Arabic"},
		{code: "gl", name: "Galician"},
		{code: "eu", name: "Basque"},
		{code: "br", name: "Breton"},
		{code: "bg", name: "Bulgarian"},
		{code: "ca", name: "Catalan"},
		{code: "hr", name: "Croatian"},
		{code: "cs", name: "Czech"},
		{code: "da", name: "Danish"},
		{code: "nl", name: "Dutch"},
		{code: "eo", name: "Esperanto"},
		{code: "et", name: "Estonian"},
		{code: "fo", name: "Faroese"},
		{code: "fr", name: "French"},
		{code: "de", name: "German"},
		{code: "el", name: "Greek"},
		{code: "id", name: "Indonesian"},
		{code: "ga", name: "Irish"},
		{code: "it", name: "Italian"},
		{code: "kk", name: "Kazakh"},
		{code: "ku", name: "Kurdish"},
		{code: "lv", name: "Latvian"},
		{code: "lt", name: "Lithuanian"},
		{code: "nr", name: "Ndebele"},
		{code: "ns", name: "Northern Sotho"},
		{code: "no", name: "Norwegian"},
		{code: "fa", name: "Persian"},
		{code: "pl", name: "Polish"},
		{code: "pt_BR", name: "Portuguese (Brazilian)"},
		{code: "pt_PT", name: "Portuguese (European)"},
		{code: "pa", name: "Punjabi"},
		{code: "ro", name: "Romanian"},
		{code: "ru", name: "Russian"},
		{code: "sk", name: "Slovak"},
		{code: "sl", name: "Slovenian"},
		{code: "st", name: "Southern Sotho"},
		{code: "es", name: "Spanish"},
		{code: "sv", name: "Swedish"},
		{code: "tl", name: "Tagalog"},
		{code: "ts", name: "Tsonga"},
		{code: "tn", name: "Tswana"},
		{code: "hsb", name: "Upper Sorbian"},
		{code: "cy", name: "Welsh"},
		{code: "xh", name: "Xhosa"}
	]

	# Password Settings
	# -----------
	# These restrict the passwords users can use when registering
	# opts are from http://antelle.github.io/passfield
	# passwordStrengthOptions:
	# 	pattern: "aA$3"
	# 	length:
	# 		min: 6
	# 		max: 128

	# Email support
	# -------------
	#
	#	ShareLaTeX uses nodemailer (http://www.nodemailer.com/) to send transactional emails.
	#	To see the range of transport and options they support, see http://www.nodemailer.com/docs/transports
	#email:
	#	fromAddress: ""
	#	replyTo: ""
	#	lifecycle: false
	## Example transport and parameter settings for Amazon SES
	#	transport: "SES"
	#	parameters:
	#		AWSAccessKeyID: ""
	#		AWSSecretKey: ""


	# Third party services
	# --------------------
	#
	# ShareLaTeX's regular newsletter is managed by mailchimp. Add your
	# credentials here to integrate with this.
	# mailchimp:
	# 	api_key: ""
	# 	list_id: ""
	#
	# Fill in your unique token from various analytics services to enable
	# them.
	# analytics:
	# 	ga:
	# 		token: ""
	# 	gaOptimize:
	# 		id: ""
	# ShareLaTeX's help desk is provided by tenderapp.com
	# tenderUrl: ""
	#
	# Client-side error logging is provided by getsentry.com
	# sentry:
	#   src: ""
	#   publicDSN: ""
	#
	# src should be either a remote url like
	#    //cdn.ravenjs.com/1.1.22/jquery,native/raven.min.js
	# or a local file in the js/libs directory.
	# The publicDSN is the token for the client-side getSentry service.

	# Production Settings
	# -------------------

	# Should javascript assets be served minified or not. Note that you will
	# need to run `grunt compile:minify` within the web-sharelatex directory
	# to generate these.
	useMinifiedJs: process.env['MINIFIED_JS'] == 'true' or false

	# Should static assets be sent with a header to tell the browser to cache
	# them.
	cacheStaticAssets: false

	# If you are running ShareLaTeX over https, set this to true to send the
	# cookie with a secure flag (recommended).
	secureCookie: false

	# 'SameSite' cookie setting. Can be set to 'lax', 'none' or 'strict'
	# 'lax' is recommended, as 'strict' will prevent people linking to projects
	# https://tools.ietf.org/html/draft-ietf-httpbis-rfc6265bis-03#section-4.1.2.7
	sameSiteCookie: 'lax'

	# If you are running ShareLaTeX behind a proxy (like Apache, Nginx, etc)
	# then set this to true to allow it to correctly detect the forwarded IP
	# address and http/https protocol information.
	behindProxy: false

	# Cookie max age (in milliseconds). Set to false for a browser session.
	cookieSessionLength: 5 * 24 * 60 * 60 * 1000 # 5 days

	# When true, only allow invites to be sent to email addresses that
	# already have user accounts
	restrictInvitesToExistingAccounts: false

	# Should we allow access to any page without logging in? This includes
	# public projects, /learn, /templates, about pages, etc.
	allowPublicAccess: if process.env["SHARELATEX_ALLOW_PUBLIC_ACCESS"] == 'true' then true else false

	enableHomepage: process.env["HOME_PAGE_ENABLED"] == 'true'

	# editor should be open by default
	editorIsOpen: if process.env["EDITOR_OPEN"] == 'false' then false else true

	# site should be open by default
	siteIsOpen: if process.env["SITE_OPEN"] == 'false' then false else true

	# Use a single compile directory for all users in a project
	# (otherwise each user has their own directory)
	# disablePerUserCompiles: true

	# Domain the client (pdfjs) should download the compiled pdf from
	pdfDownloadDomain: process.env["PDF_DOWNLOAD_DOMAIN"]  #"http://clsi-lb:3014"

	# Maximum size of text documents in the real-time editing system.
	max_doc_length: 2 * 1024 * 1024 # 2mb

	# Maximum JSON size in HTTP requests
  # We should be able to process twice the max doc length, to allow for
  #   - the doc content
  #   - text ranges spanning the whole doc
	#
  # There's also overhead required for the JSON encoding and the UTF-8 encoding,
	# theoretically up to 3 times the max doc length. On the other hand, we don't
	# want to block the event loop with JSON parsing, so we try to find a
	# practical compromise.
	max_json_request_size: parseInt(process.env["MAX_JSON_REQUEST_SIZE"]) || 6 * 1024 * 1024  # 6 MB

	# Internal configs
	# ----------------
	path:
		# If we ever need to write something to disk (e.g. incoming requests
		# that need processing but may be too big for memory, then write
		# them to disk here).
		dumpFolder: "./data/dumpFolder"
		uploadFolder: "./data/uploads"

	# Automatic Snapshots
	# -------------------
	automaticSnapshots:
		# How long should we wait after the user last edited to
		# take a snapshot?
		waitTimeAfterLastEdit: 5 * minutes
		# Even if edits are still taking place, this is maximum
		# time to wait before taking another snapshot.
		maxTimeBetweenSnapshots: 30 * minutes

	# Smoke test
	# ----------
	# Provide log in credentials and a project to be able to run
	# some basic smoke tests to check the core functionality.
	#
	smokeTest:
		user: process.env['SMOKE_TEST_USER']
		userId: process.env['SMOKE_TEST_USER_ID']
		password: process.env['SMOKE_TEST_PASSWORD']
		projectId: process.env['SMOKE_TEST_PROJECT_ID']
		rateLimitSubject: process.env['SMOKE_TEST_RATE_LIMIT_SUBJECT'] or "127.0.0.1"

	appName: process.env['APP_NAME'] or "ShareLaTeX (Community Edition)"

	adminEmail: process.env['ADMIN_EMAIL'] or "placeholder@example.com"

	salesEmail: process.env['SALES_EMAIL'] or "placeholder@example.com"

	statusPageUrl: process.env['OVERLEAF_STATUS_URL'] or "status.overleaf.com"

	brandPrefix: process.env['BRAND_PREFIX'] or "sl-" # Set to 'ol-' for overleaf styles

	nav:
		title: "ShareLaTeX Community Edition"

		left_footer: [{
			text: "Powered by <a href='https://www.sharelatex.com'>ShareLaTeX</a> © 2016"
		}]

		right_footer: [{
			text: "<i class='fa fa-github-square'></i> Fork on Github!"
			url: "https://github.com/sharelatex/sharelatex"
		}]

		showSubscriptionLink: false

		header_extras: []
		# Example:
		#   header_extras: [{text: "Some Page", url: "http://example.com/some/page", class: "subdued"}]

	recaptcha:
		disabled:
			invite: true
			register: true

	customisation: {}

#	templates: [{
#		name : "cv_or_resume",
#		url : "/templates/cv"
#	}, {
#		name : "cover_letter",
#		url : "/templates/cover-letters"
#	}, {
#		name : "journal_article",
#		url : "/templates/journals"
#	}, {
#		name : "presentation",
#		url : "/templates/presentations"
#	}, {
#		name : "thesis",
#		url : "/templates/thesis"
#	}, {
#		name : "bibliographies",
#		url : "/templates/bibliographies"
#	}, {
#		name : "view_all",
#		url : "/templates"
#	}]


	redirects:
		"/templates/index": "/templates/"

	reloadModuleViewsOnEachRequest: process.env['NODE_ENV'] == 'development'

	domainLicences: [

	]

	sixpack:
		domain:""
	# ShareLaTeX Server Pro options (https://www.sharelatex.com/university/onsite.html)
	# ----------



	# LDAP
	# ----------
	# Settings below use a working LDAP test server kindly provided by forumsys.com
	# When testing with forumsys.com use username = einstein and password = password

	# ldap :
	# 	host: 'ldap://ldap.forumsys.com'
	# 	dn: 'uid=:userKey,dc=example,dc=com'
	# 	baseSearch: 'dc=example,dc=com'
	# 	filter: "(uid=:userKey)"
	# 	failMessage: 'LDAP User Fail'
	# 	fieldName: 'LDAP User'
	# 	placeholder: 'email@example.com'
	# 	emailAtt: 'mail'
	# 	anonymous: false
	#	adminDN: 'cn=read-only-admin,dc=example,dc=com'
	#	adminPW: 'password'
	#	starttls: true
	#	tlsOptions:
	#		rejectUnauthorized: false
	#		ca: ['/etc/ldap/ca_certs.pem']

	#templateLinks: [{
	#	name : "CV projects",
	#	url : "/templates/cv"
	#},{
	#	name : "all projects",
	#	url: "/templates/all"
	#}]

	rateLimit:
		autoCompile:
			everyone: process.env['RATE_LIMIT_AUTO_COMPILE_EVERYONE'] or 100
			standard: process.env['RATE_LIMIT_AUTO_COMPILE_STANDARD'] or 25

	# currentImage: "texlive-full:2017.1"
	# imageRoot: "<DOCKER REPOSITORY ROOT>" # without any trailing slash
	
	compileBodySizeLimitMb: process.env['COMPILE_BODY_SIZE_LIMIT_MB'] or 5

	validRootDocExtensions: ['tex', 'Rtex', 'ltx']

	emailConfirmationDisabled: (process.env['EMAIL_CONFIRMATION_DISABLED'] == "true") or false

	# allowedImageNames: [
	# 	{imageName: 'texlive-full:2017.1', imageDesc: 'TeXLive 2017'}
	# 	{imageName:   'wl_texlive:2018.1', imageDesc: 'Legacy OL TeXLive 2015'}
	# 	{imageName: 'texlive-full:2016.1', imageDesc: 'Legacy SL TeXLive 2016'}
	# 	{imageName: 'texlive-full:2015.1', imageDesc: 'Legacy SL TeXLive 2015'}
	# 	{imageName: 'texlive-full:2014.2', imageDesc: 'Legacy SL TeXLive 2014.2'}
	# ]

	# module options
	# ----------
	modules:
		sanitize:
			options:
				allowedTags: [ 'h1', 'h2', 'h3', 'h4', 'h5', 'h6', 'blockquote', 'p', 'a', 'ul', 'ol', 'nl', 'li', 'b', 'i', 'strong', 'em', 'strike', 'code', 'hr', 'br', 'div', 'table', 'thead', 'col', 'caption', 'tbody', 'tr', 'th', 'td', 'tfoot', 'pre', 'iframe', 'img', 'figure', 'figcaption', 'span', 'source', 'video', 'del' ]
				allowedAttributes:
					'a': [ 'href', 'name', 'target', 'class', 'event-tracking', 'event-tracking-ga', 'event-tracking-label', 'event-tracking-trigger' ]
					'div': [ 'class', 'id', 'style' ]
					'h1': [ 'class', 'id' ]
					'h2': [ 'class', 'id' ]
					'h3': [ 'class', 'id' ]
					'h4': [ 'class', 'id' ]
					'h5': [ 'class', 'id' ]
					'h6': [ 'class', 'id' ]
					'col': [ 'width' ]
					'figure': [ 'class', 'id', 'style']
					'figcaption': [ 'class', 'id', 'style']
					'i': [ 'aria-hidden', 'aria-label', 'class', 'id' ] 
					'iframe': [ 'allowfullscreen', 'frameborder', 'height', 'src', 'style', 'width' ]
					'img': [ 'alt', 'class', 'src', 'style' ]
					'source': [ 'src', 'type' ]
					'span': [ 'class', 'id', 'style' ]
					'table': [ 'border', 'class', 'id', 'style' ]
					'td': [ 'colspan', 'rowspan', 'headers', 'style' ]
					'th': [ 'abbr', 'headers', 'colspan', 'rowspan', 'scope', 'sorted', 'style' ]
					'tr': [ 'class' ]
					'video': [ 'alt', 'class', 'controls', 'height', 'width' ]