BuildOperationStartedNotification.java

/*
 * Copyright 2017 the original author or authors.
 *
 * 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 org.gradle.internal.operations.notify;

import org.gradle.internal.scan.UsedByScanPlugin;

/**
 * A notification that a build operation has started.
 *
 * The methods of this interface are awkwardly prefixed to allow
 * internal types to implement this interface along with other internal interfaces
 * without risking method collision.
 *
 * @since 4.0
 */
@UsedByScanPlugin
public interface BuildOperationStartedNotification {

    /**
     * A unique, opaque, value identifying this operation.
     */
    Object getNotificationOperationId();

    /**
     * A structured object providing details about the operation to be performed.
     */
    Object getNotificationOperationDetails();

    /*
        NOTES:

        Parent operation IDs and timestamps are conspicuously absent here.

        The build scan plugin does not currently need parent IDs.
        Before we add it here, we need to define the semantics of details-less operations
        and this interface. Specifically, what is to happen if a parent operation is details-less
        but the child operation has details.

        Timestamps are missing because the build scan plugin has different timestamp requirements.
        Specifically, it goes to some effort to provide monotonic timestamps (and the observed value) if different,
        and deterministic ordering of events that yield the same timestamp value (e.g. two clock reads quicker than the clock granularity).

        These are both things to be worked out.
        When we do, they will be added to this interface in some form.
     */

}