com.amazonaws.services.dynamodbv2.replication.manager.models.ReplicationGroupCoordinator.java Source code

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Here is the source code for com.amazonaws.services.dynamodbv2.replication.manager.models.ReplicationGroupCoordinator.java

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/*
 * Copyright 2014 Amazon.com, Inc. or its affiliates. All Rights Reserved.
 *
 * Licensed under the Amazon Software License (the "License").
 * You may not use this file except in compliance with the License.
 * A copy of the License is located at
 *
 * http://aws.amazon.com/asl/
 *
 * or in the "license" file accompanying this file. This file 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.amazonaws.services.dynamodbv2.replication.manager.models;

import java.io.IOException;
import java.util.logging.Logger;

import javax.ws.rs.ProcessingException;
import javax.ws.rs.client.Client;
import javax.ws.rs.client.ClientBuilder;
import javax.ws.rs.client.Entity;
import javax.ws.rs.client.WebTarget;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;

import org.glassfish.jersey.client.ClientProperties;

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public abstract class ReplicationGroupCoordinator {
    public static final String DESCRIBE_REPLICATION_GROUP_API = "DescribeReplicationGroup";
    public static final String DESCRIBE_REPLICATION_COORDINATOR_API = "DescribeReplicationCoordinator";
    public static final String DESCRIBE_TABLES_API = "DescribeTables";
    public static final String START_REPLICATION_API = "StartReplication";
    public static final String STOP_REPLICATION_API = "StopReplication";
    public static final String REPLICATION_COORDINATOR_STATUS_FIELD = "ReplicationCoordinatorStatus";
    protected String endpoint;
    protected Client client;
    protected String id;
    protected Logger logger = Logger.getLogger(getClass().getName());
    protected ReplicationGroupStatus status;

    public ReplicationGroupCoordinator(String groupId) {
        client = ClientBuilder.newClient();
        this.id = groupId;
    }

    public String getId() {
        return id;
    }

    public Response listTables() throws ReplicationGroupCoordinatorException {
        WebTarget target = client.target(endpoint).path(DESCRIBE_REPLICATION_GROUP_API);
        String json = target.request().get(String.class);
        logger.finest(json);
        try {
            JsonNode tables = new ObjectMapper().readTree(json);
            return Response.ok(tables).build();
        } catch (IOException e) {
            throw new ReplicationGroupCoordinatorException("Failed to parse response from coordinator: " + json);
        }
    }

    public Response getTable(String region, String tableName, String accountId)
            throws ReplicationGroupCoordinatorException {
        WebTarget target = client.target(endpoint).path(DESCRIBE_TABLES_API);
        String json = target.request().get(String.class);
        logger.finest(json);
        try {
            JsonNode tables = new ObjectMapper().readTree(json);
            if (tables.isArray() && tables.size() == 1) {
                return Response.ok(tables.get(0)).build();
            } else {
                throw new ReplicationGroupCoordinatorException(
                        "Unnexpected response from the coordinator. It should be an array with one table object in it, but received: "
                                + json);
            }
        } catch (IOException e) {
            throw new ReplicationGroupCoordinatorException(
                    "Failed to parse response from the coordinator: " + json);
        }
    }

    public Response addTable(Table table) {
        // TODO 
        return Response.status(Status.NOT_IMPLEMENTED).build();
    }

    public Response deleteTable(String region, String tableName, String accountId) {
        // TODO 
        return Response.status(Status.NOT_IMPLEMENTED).build();
    }

    public Response startReplication() {
        ReplicationGroupStatus status = getStatus();
        if (status == ReplicationGroupStatus.STOPPED) {
            logger.info("Starting replication: " + this.getId());
            WebTarget target = client.target(endpoint).path(START_REPLICATION_API);
            target.request().post(Entity.entity("", MediaType.APPLICATION_JSON_TYPE));
        }
        return Response.ok(getStatus()).build();

    }

    public Response stopReplication() {
        ReplicationGroupStatus status = getStatus();
        if (status == ReplicationGroupStatus.RUNNING) {
            logger.info("Stopping replication: " + this.getId());
            WebTarget target = client.target(endpoint).path(STOP_REPLICATION_API);
            target.request().post(Entity.entity("", MediaType.APPLICATION_JSON_TYPE));
        }
        return Response.ok(getStatus()).build();
    }

    public ReplicationGroupStatus getStatus() {
        Client client = ClientBuilder.newClient();

        client.property(ClientProperties.CONNECT_TIMEOUT, 1000);
        client.property(ClientProperties.READ_TIMEOUT, 1000);

        WebTarget target = client.target(endpoint).path(DESCRIBE_REPLICATION_COORDINATOR_API);
        try {
            JsonNode json = target.request().get(JsonNode.class);
            logger.fine("Received " + json);
            JsonNode statusField = json.get(REPLICATION_COORDINATOR_STATUS_FIELD);
            if (statusField != null) {
                return ReplicationGroupStatus.valueOf(statusField.textValue());
            } else {
                return ReplicationGroupStatus.UNKNOWN;
            }
        } catch (ProcessingException pe) {
            if (this.status == ReplicationGroupStatus.BOOTSTRAPPING) {
                return ReplicationGroupStatus.BOOTSTRAPPING;
            } else {
                return ReplicationGroupStatus.COORDINATOR_UNREACHABLE;
            }
        }
    };

    public abstract void launch();

    public abstract void terminate();

}