snowplow-referer-parser / scala-referer-parser

Scala library for extracting marketing attribution data from referrer URLs

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referer-parser Scala library

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This is the Scala implementation of referer-parser, the library for extracting attribution data from referer (sic) URLs.

The implementation uses a JSON version of the shared 'database' of known referers found in referers.yml.

The Scala implementation is a core component of Snowplow, the open-source web-scale analytics platform.


All effects within the Scala implementation are wrapped in Sync from cats-effect. In these examples we use IO, but anything that implements Sync can be used.

import com.snowplowanalytics.refererparser.Parser
import cats.effect.IO

val refererUrl = ""
val pageUrl    = "http:/" // Our current URL

val referersJsonPath = "/opt/referers/referers.json"

// We use EitherT to handle exceptions. The IO routine will short circuit if an exception is returned.
val io: EitherT[IO, Exception, Unit] = for {
  // We can instantiate a new Parse instance with Parse.create
  parser <- EitherT(Parser.create[IO](referersJsonPath))

  // Referer is a sealed hierarchy of different referer types
  referer1 <- EitherT.fromOption[IO](parser.parse(refererUrl, pageUrl),
    new Exception("No parseable referer"))
  _ <- EitherT.right(IO { println(referer1) })
    // => SearchReferer(Google, Some(gateway oracle cards denise linn))

  // You can provide a list of domains which should be considered internal
  referer2 <- EitherT.fromOption[IO](parser.parse(
      new URI(""),
      List("", "")
    ), new Exception("No parseable referer"))
  _ <- EitherT.right(IO { println(referer2) })
    // => InternalReferer

  // Various overloads are available for common cases, for instance
  maybeReferer1 = parser.parse("")
  maybeReferer2 = parser.parse(new URI(""), None, Nil)
  _ <- EitherT.right(IO { println( maybeReferer1 == maybeReferer2 ) }) // => true
} yield Unit


More examples can be seen in ParseTest.scala. See Parser.scala for all overloads.


Add this to your SBT config:

val refererParser = "com.snowplowanalytics" %% "referer-parser" % "0.5.0"


  1. Fork it
  2. Create your feature branch (git checkout -b my-new-feature)
  3. Commit your changes (git commit -am 'Add some feature')
  4. Push to the branch (git push origin my-new-feature)
  5. Create new Pull Request

Copyright and license

The referer-parser Java/Scala library is copyright 2012-2018 Snowplow Analytics Ltd.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this software except in compliance with the License.

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.