com.johnsnowlabs.nlp.util.io.ExternalResource.scala Maven / Gradle / Ivy

/*
 * Copyright 2017-2022 John Snow Labs
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * 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.
 */

package com.johnsnowlabs.nlp.util.io

import com.johnsnowlabs.nlp.annotators.param.WritableAnnotatorComponent
import com.johnsnowlabs.nlp.serialization.SerializedExternalResource

/** This represents an external source which contains information into how an external resource
  * shall be read by Spark-NLP's Resource Helper.
  *   - `ReadAs.TEXT` will configure the file to be read locally as text
  *   - `ReadAs.BINARY` will configure the file to be read locally as binary
  *   - `ReadAs.SPARK` will configure the file to be read by Spark. `"format"` will need to be
  *     defined in `options`.
  *
  * ==Example==
  * {{{
  * ExternalResource(
  *   "src/test/resources/regex-matcher/rules.txt",
  *   ReadAs.TEXT,
  *   Map("delimiter" -> ",")
  * )
  *
  * ExternalResource(
  *   "src/test/resources/regex-matcher/rules.txt",
  *   ReadAs.SPARK,
  *   Map("format" -> "text", "delimiter" -> ",")
  * )
  * }}}
  *
  * @param path
  *   Path to the resource
  * @param readAs
  *   How to interpret the resource. Possible values are `ReadAs.SPARK, ReadAs.TEXT,
  *   ReadAs.BINARY`
  * @param options
  *   Options for Spark. Option `format` needs to be set if `readAs` is set to `ReadAs.SPARK`
  */
case class ExternalResource(path: String, readAs: ReadAs.Format, options: Map[String, String])
    extends WritableAnnotatorComponent {

  if (readAs == ReadAs.SPARK)
    require(
      options.contains("format"),
      "Created ExternalResource to read as SPARK but key 'format' " +
        "in options is not provided. Can be any spark.read.format type. e.g. 'text' or 'json' or 'parquet'")

  override def serialize: SerializedExternalResource = {
    SerializedExternalResource(path, readAs.toString, options)
  }

}
object ExternalResource {
  import scala.collection.JavaConverters._
  def fromJava(
      path: String,
      readAs: String,
      options: java.util.HashMap[String, String]): ExternalResource = {
    ExternalResource(path, readAs, options.asScala.toMap)
  }
}