Admin tool Main.scala contains MIT-licensed code from Scallop without attribution

[pjfanning]

tools/admin/src/main/scala/org/apache/openwhisk/core/cli/Main.scala contains code copied from Scallop, which is MIT-licensed:

  private def printErr(message: String): Unit = {
    //Taken from ScallopConf
    if (overrideColorOutput.value.getOrElse(System.console() != null)) {
      Console.err.println("[\u001b[31m%s\u001b[0m] Error: %s" format (printedName, message))
    } else {
      // no colors on output
      Console.err.println("[%s] Error: %s" format (printedName, message))
    }
  }

It was added in daa14c6 (#3722, 2018), when the admin tool depended on Scallop 3.1.2. It is Scallop's default errorMessageHandler, minus the final sys.exit(1): see jvm/src/main/scala/org.rogach.scallop/ScallopConf.scala lines 73-81 at v3.1.2:

  errorMessageHandler = { message =>
    if (overrideColorOutput.value.getOrElse(System.console() != null)) {
      Console.err.println("[\u001b[31m%s\u001b[0m] Error: %s" format (printedName, message))
    } else {
      // no colors on output
      Console.err.println("[%s] Error: %s" format (printedName, message))
    }
    sys.exit(1)
  }

Scallop is licensed under the MIT License, Copyright (C) 2012 Platon Pronko and Chris Hodapp. MIT is Category A, so the code can be included, but the MIT licence requires its copyright and permission notice to be kept with copied code. Currently the file only carries the ASF header, and neither LICENSE.txt nor NOTICE.txt mentions Scallop.

Suggested fix, either:

1. Rewrite printErr independently (it is a few lines of error printing) and drop the "Taken from ScallopConf" comment; or
2. Keep it, add the Scallop copyright line to the file below the ASF header, and add an entry to LICENSE.txt for Scallop (MIT, with its copyright line and licence text), naming the file.

Apache OpenServerless vendors this file and tracks the same problem in apache/openserverless#264.