Facebook Crawler

[dbacinski]

Facebook crawler data are missing in default bots:

class FacebookData private constructor() : CrawlerData {
    override fun getIdentifier(): String {
        return "FACEBOOKBOT"
    }

    override fun getUserAgentChecker(): Predicate<String> {
        return PREDICATE
    }

    override fun getIps(): Set<String> {
        return emptySet()
    }

    override fun getHostnames(): Set<String> {
        return HOSTNAMES
    }

    companion object {
        private val PREDICATE =
            Predicate<String> { userAgent ->
                userAgent.contains("facebookexternalhit/1.1") || userAgent.contains("facebookcatalog/1.0")
            }
        private val HOSTNAMES = ImmutableSet.of("fbsv.net")
        val instance = FacebookData()
    }
}