MicroPipelineResource.java

/**
 * Copyright 2015 Otto (GmbH & Co KG)
 *
 * 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.ottogroup.bi.spqr.node.resource.pipeline;

import javax.ws.rs.DELETE;
import javax.ws.rs.GET;
import javax.ws.rs.POST;
import javax.ws.rs.PUT;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.QueryParam;

import org.apache.commons.lang3.StringUtils;

import com.codahale.metrics.annotation.Timed;
import com.ottogroup.bi.spqr.exception.ComponentInitializationFailedException;
import com.ottogroup.bi.spqr.exception.NonUniqueIdentifierException;
import com.ottogroup.bi.spqr.exception.PipelineInstantiationFailedException;
import com.ottogroup.bi.spqr.exception.QueueInitializationFailedException;
import com.ottogroup.bi.spqr.exception.RequiredInputMissingException;
import com.ottogroup.bi.spqr.node.resource.pipeline.MicroPipelineShutdownResponse.MicroPipelineShutdownState;
import com.ottogroup.bi.spqr.pipeline.MicroPipeline;
import com.ottogroup.bi.spqr.pipeline.MicroPipelineConfiguration;
import com.ottogroup.bi.spqr.pipeline.MicroPipelineManager;
import com.ottogroup.bi.spqr.pipeline.MicroPipelineValidationResult;

/**
 * REST resource providing access to {@link MicroPipeline pipelines} managed by {@link MicroPipelineManager}. The resource provides methods for
 * <ul>
 *   <li>{@link MicroPipelineResource#instantiatePipeline(String, MicroPipelineConfiguration) pipeline instantiation}</li>
 *   <li>{@link MicroPipelineResource#shutdown(String) pipeline shutdown}</li>
 * </ul>
 * @author mnxfst
 * @since Mar 13, 2015
 */
@Path("/pipelines")
public class MicroPipelineResource {

	public static final String ERROR_MSG_PIPELINE_ID_MISSING = "Missing required pipeline id";
	public static final String ERROR_MSG_PIPELINE_CONFIGURATION_MISSING = "Missing required pipeline configuration";
	public static final String ERROR_MSG_PIPELINE_IDS_DIFFER = "Pipeline id referenced in path is not equal to id found in configuration"; 
	
	public static final String LIST_PIPELINES_MODE_FULL = "FULL";
	public static final String LIST_PIPELINES_MODE_SIMPLE = "SIMPLE";
	
	private final MicroPipelineManager microPipelineManager;
	
	/**
	 * Initializes the micro pipeline resource using the provided input
	 * @param microPipelineManager
	 */
	public MicroPipelineResource(final MicroPipelineManager microPipelineManager) throws RequiredInputMissingException {
		if(microPipelineManager == null)
			throw new RequiredInputMissingException("Missing required micro pipeline manager instance");
		
		this.microPipelineManager = microPipelineManager;
	}
	
	/**
	 * Creates a new pipeline for the given identifier and {@link MicroPipelineConfiguration}
	 * @param pipelineId
	 * @param configuration
	 * @return
	 */
	@Produces(value = "application/json")
	@Timed(name = "pipeline-instantiation")
	@POST
	public MicroPipelineInstantiationResponse instantiatePipeline(final MicroPipelineConfiguration configuration) {		

		if(configuration == null)
			return new MicroPipelineInstantiationResponse("", MicroPipelineValidationResult.MISSING_CONFIGURATION, ERROR_MSG_PIPELINE_CONFIGURATION_MISSING);
				
		if(StringUtils.isBlank(configuration.getId()))
			return new MicroPipelineInstantiationResponse("", MicroPipelineValidationResult.MISSING_CONFIGURATION, ERROR_MSG_PIPELINE_ID_MISSING);

		try {
			String id = this.microPipelineManager.executePipeline(configuration);
			return new MicroPipelineInstantiationResponse(id, MicroPipelineValidationResult.OK, "");
		} catch (RequiredInputMissingException e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.MISSING_CONFIGURATION, e.getMessage());
		} catch (QueueInitializationFailedException e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.QUEUE_INITIALIZATION_FAILED, e.getMessage());
		} catch (ComponentInitializationFailedException e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.COMPONENT_INITIALIZATION_FAILED, e.getMessage());
		} catch (PipelineInstantiationFailedException e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.PIPELINE_INITIALIZATION_FAILED, e.getMessage());
		} catch (NonUniqueIdentifierException e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.NON_UNIQUE_PIPELINE_ID, e.getMessage());
		} catch(Exception e) {
			return new MicroPipelineInstantiationResponse(configuration.getId(), MicroPipelineValidationResult.TECHNICAL_ERROR, e.getMessage());
		}
	}
	
	/**
	 * Creates or updates a pipeline for the given identifier and {@link MicroPipelineConfiguration}
	 * @param pipelineId
	 * @param configuration
	 * @return
	 */
	@Produces(value = "application/json")
	@Timed(name = "pipeline-instantiation")
	@PUT
	@Path("{pipelineId}")
	public MicroPipelineInstantiationResponse updatePipeline(@PathParam("pipelineId") final String pipelineId, final MicroPipelineConfiguration configuration) {
		
		if(StringUtils.isBlank(pipelineId))
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.MISSING_CONFIGURATION, ERROR_MSG_PIPELINE_ID_MISSING);
		
		if(configuration == null)
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.MISSING_CONFIGURATION, ERROR_MSG_PIPELINE_CONFIGURATION_MISSING);
		
		if(!StringUtils.equalsIgnoreCase(StringUtils.trim(pipelineId), configuration.getId())) 
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.PIPELINE_INITIALIZATION_FAILED, ERROR_MSG_PIPELINE_IDS_DIFFER);

		try {
			// shutdown running instance of pipeline 
			if(this.microPipelineManager.hasPipeline(pipelineId)) {
				this.microPipelineManager.shutdownPipeline(pipelineId);
			}
			String id = this.microPipelineManager.executePipeline(configuration);
			return new MicroPipelineInstantiationResponse(id, MicroPipelineValidationResult.OK, "");
		} catch (RequiredInputMissingException e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.MISSING_CONFIGURATION, e.getMessage());
		} catch (QueueInitializationFailedException e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.QUEUE_INITIALIZATION_FAILED, e.getMessage());
		} catch (ComponentInitializationFailedException e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.COMPONENT_INITIALIZATION_FAILED, e.getMessage());
		} catch (PipelineInstantiationFailedException e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.PIPELINE_INITIALIZATION_FAILED, e.getMessage());
		} catch (NonUniqueIdentifierException e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.NON_UNIQUE_PIPELINE_ID, e.getMessage());
		} catch(Exception e) {
			return new MicroPipelineInstantiationResponse(pipelineId, MicroPipelineValidationResult.TECHNICAL_ERROR, e.getMessage());
		}
		
	}
	
	/**
	 * Shuts down the referenced {@link MicroPipeline}
	 * @param pipelineId
	 * @return
	 */
	@Produces(value = "application/json")
	@Timed(name = "pipeline-shutdown")
	@DELETE
	@Path("{pipelineId}")
	public MicroPipelineShutdownResponse shutdown(@PathParam("pipelineId") final String pipelineId) {
		
		if(StringUtils.isBlank(pipelineId))
			return new MicroPipelineShutdownResponse(pipelineId, MicroPipelineShutdownState.PIPELINE_ID_MISSING, ERROR_MSG_PIPELINE_ID_MISSING);

		try {			
			return new MicroPipelineShutdownResponse(this.microPipelineManager.shutdownPipeline(pipelineId), MicroPipelineShutdownState.OK, "");
		} catch(Exception e) {
			return new MicroPipelineShutdownResponse(pipelineId, MicroPipelineShutdownState.TECHNICAL_ERROR, e.getMessage());
		}
	}

	/**
	 * Lists all {@link MicroPipeline} instances registered with this node. Depending on the <i>mode</i> parameter, the 
	 * result contains either just a list of pipeline identifiers or contains the associated {@link MicroPipelineConfiguration} as well. 
	 * @param mode result mode: SIMPLE, FULL (default: SIMPLE) 
	 * @return
	 */
	@Produces(value = "application/json" )
	@Timed(name = "pipeline-list" )
	@GET
	@Path("list")
	public ListRegisteredMicroPipelinesResponse listRegisteredPipelines(@QueryParam("mode") final String mode) {
		if(StringUtils.isBlank(mode) || StringUtils.equalsIgnoreCase(mode, LIST_PIPELINES_MODE_SIMPLE)) {
			return new ListRegisteredMicroPipelinesResponse(this.microPipelineManager.getProcessingNodeId(), this.microPipelineManager.getPipelineIds());
		}
		
		return new ListRegisteredMicroPipelinesResponse(this.microPipelineManager.getProcessingNodeId(), this.microPipelineManager.getPipelineIds(), this.microPipelineManager.getPipelineConfigurations());		
	}
}