com.dimajix.flowman.spec.target.CopyFileTarget.scala Maven / Gradle / Ivy

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/*
 * Copyright 2018-2019 Kaya Kupferschmidt
 *
 * 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.dimajix.flowman.spec.target

import com.fasterxml.jackson.annotation.JsonProperty
import org.apache.hadoop.fs.Path
import org.slf4j.LoggerFactory

import com.dimajix.common.No
import com.dimajix.common.Trilean
import com.dimajix.common.Yes
import com.dimajix.flowman.execution.Context
import com.dimajix.flowman.execution.Execution
import com.dimajix.flowman.execution.Phase
import com.dimajix.flowman.execution.VerificationFailedException
import com.dimajix.flowman.model.BaseTarget
import com.dimajix.flowman.model.ResourceIdentifier
import com.dimajix.flowman.model.Target


case class CopyFileTarget(
    instanceProperties:Target.Properties,
    source:Path,
    target:Path,
    overwrite:Boolean
) extends BaseTarget {
    private val logger = LoggerFactory.getLogger(classOf[CopyFileTarget])

    /**
     * Returns all phases which are implemented by this target in the execute method
     * @return
     */
    override def phases : Set[Phase] = Set(Phase.BUILD, Phase.VERIFY, Phase.TRUNCATE, Phase.DESTROY)

    /**
     * Returns a list of physical resources produced by this target
     *
     * @return
     */
    override def provides(phase: Phase): Set[ResourceIdentifier] = {
        phase match {
            case Phase.BUILD => Set(ResourceIdentifier.ofFile(target))
            case _ => Set()
        }
    }

    /**
     * Returns a list of physical resources required by this target
     *
     * @return
     */
    override def requires(phase: Phase): Set[ResourceIdentifier] = {
        phase match {
            case Phase.BUILD => Set(ResourceIdentifier.ofFile(source))
            case _ => Set()
        }
    }

    /**
     * Returns the state of the target, specifically of any artifacts produces. If this method return [[Yes]],
     * then an [[execute]] should update the output, such that the target is not 'dirty' any more.
     *
     * @param execution
     * @param phase
     * @return
     */
    override def dirty(execution: Execution, phase: Phase): Trilean = {
        phase match {
            case Phase.BUILD =>
                val fs = execution.fs
                val dst = fs.file(target)
                !dst.exists()
            case Phase.VERIFY => Yes
            case Phase.TRUNCATE|Phase.DESTROY =>
                val fs = execution.fs
                val dst = fs.file(target)
                dst.exists()
            case _ => No
        }
    }

    /**
      * Abstract method which will perform the output operation. All required tables need to be
      * registered as temporary tables in the Spark session before calling the execute method.
      *
      * @param executor
      */
    override protected def build(executor: Execution): Unit = {
        val fs = executor.fs
        val src = fs.file(source)
        val dst = fs.file(target)
        logger.info(s"Copying remote file '$src' to remote file '$dst' (overwrite=$overwrite)")
        src.copy(dst, overwrite)
    }

    /**
     * Performs a verification of the build step or possibly other checks.
     *
     * @param executor
     */
    override def verify(executor: Execution) : Unit = {
        require(executor != null)

        val file = executor.fs.file(target)
        if (!file.exists()) {
            logger.error(s"Verification of target '$identifier' failed - location '$target' does not exist")
            throw new VerificationFailedException(identifier)
        }
    }

    /**
      * Deletes data of a specific target
      *
      * @param executor
      */
    override protected def truncate(executor: Execution): Unit = {
        val fs = executor.fs
        val dst = fs.file(target)
        if (dst.exists()) {
            logger.info(s"Removing file '$dst'")
            dst.delete(true)
        }
    }

    /**
     * Completely destroys the resource associated with this target. This will delete both the phyiscal data and
     * the table definition
     *
     * @param executor
     */
    override protected def destroy(executor: Execution): Unit = {
        truncate(executor)
    }
}



class CopyFileTargetSpec extends TargetSpec {
    @JsonProperty(value = "source", required = true) private var source: String = ""
    @JsonProperty(value = "target", required = true) private var target: String = ""
    @JsonProperty(value = "overwrite", required = false) private var overwrite: String = "true"

    override def instantiate(context: Context): CopyFileTarget = {
        CopyFileTarget(
            instanceProperties(context),
            new Path(context.evaluate(source)),
            new Path(context.evaluate(target)),
            context.evaluate(overwrite).toBoolean
        )
    }
}