server/src/com/cloud/maint/UpgradeManager.java

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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package com.cloud.maint;

import com.cloud.utils.component.Manager;

/**
 * Upgrade Manager manages the upgrade of agents.
 *
 */
public interface UpgradeManager extends Manager {
    enum State {
        RequiresUpdate,
        WaitingForUpdate,
        UpToDate;
    };
    
    /**
     * Checks if the agent requires an upgrade before it can process
     * any commands.
     * 
     * @param hostId host id.
     * @return state of the agent.
     */
    State registerForUpgrade(long hostId, String version);
    
    /**
     * @return the URL to download the new agent.
     */
//    String getAgentUrl();
    

}