com.ibm.og.object.AbstractObjectNameConsumer.java Source code

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Here is the source code for com.ibm.og.object.AbstractObjectNameConsumer.java

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/* Copyright (c) IBM Corporation 2016. All Rights Reserved.
 * Project name: Object Generator
 * This project is licensed under the Apache License 2.0, see LICENSE.
 */

package com.ibm.og.object;

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkNotNull;

import java.util.Set;

import com.ibm.og.api.Operation;
import com.ibm.og.api.Request;
import com.ibm.og.api.Response;
import com.ibm.og.http.HttpUtil;
import com.ibm.og.util.Context;
import com.ibm.og.util.Pair;
import com.google.common.collect.ImmutableSet;
import com.google.common.eventbus.Subscribe;

/**
 * A consumer of object names
 * 
 * @since 1.0
 */
public abstract class AbstractObjectNameConsumer {
    protected final ObjectManager objectManager;
    private final Operation operation;
    private final Set<Integer> statusCodes;

    /**
     * Constructs an instance
     * 
     * @param objectManager the object manager for this instance to work with
     * @param operation the operation type this instance should work with
     * @param statusCodes the status codes this instance should work with
     * @throws IllegalArgumentException if any status code in status codes is invalid
     */
    public AbstractObjectNameConsumer(final ObjectManager objectManager, final Operation operation,
            final Set<Integer> statusCodes) {
        this.objectManager = checkNotNull(objectManager);
        this.operation = checkNotNull(operation);
        this.statusCodes = ImmutableSet.copyOf(statusCodes);
        checkArgument(!this.statusCodes.isEmpty(), "statusCodes must not be empty");
        for (final int statusCode : this.statusCodes) {
            checkArgument(HttpUtil.VALID_STATUS_CODES.contains(statusCode),
                    "all statusCodes in list must be valid status codes [%s]", statusCode);
        }
    }

    /**
     * Consumes operations and processes object names
     * 
     * @param operation the operation to process
     */
    @Subscribe
    public void consume(final Pair<Request, Response> operation) {
        checkNotNull(operation);
        final Request request = operation.getKey();
        final Response response = operation.getValue();

        // if this consumer is not relevant for the current response, ignore
        if (this.operation != request.getOperation()) {
            return;
        }

        // make sure Http request matches OG operation (e.g. PUT == WRITE/OVERWRITE)
        if (request.getMethod() != HttpUtil.toMethod(request.getOperation())) {
            return;
        }

        // if the status code of this response does not match what can be consumed, ignore
        if (!this.statusCodes.contains(response.getStatusCode())) {
            return;
        }

        if (request.getContext().containsKey(Context.X_OG_SEQUENTIAL_OBJECT_NAME)) {
            return;
        }

        final String objectString = getObjectString(request, response);
        if (objectString == null) {
            throw new IllegalStateException("Unable to determine object");
        }

        final ObjectMetadata objectName = getObjectName(request, response);
        updateObjectManager(objectName);
    }

    private ObjectMetadata getObjectName(final Request request, final Response response) {
        final String objectString = getObjectString(request, response);
        final long objectSize = getObjectSize(request);
        final int containerSuffix = getContainerSuffix(request);
        return LegacyObjectMetadata.fromMetadata(objectString, objectSize, containerSuffix);
    }

    protected String getObjectString(final Request request, final Response response) {
        String objectString = request.getContext().get(Context.X_OG_OBJECT_NAME);
        // SOH writes
        if (objectString == null) {
            objectString = response.getContext().get(Context.X_OG_OBJECT_NAME);
        }

        return objectString;
    }

    private long getObjectSize(final Request request) {
        if (this.operation == Operation.WRITE) {
            return request.getBody().getSize();
        }
        return Long.parseLong(request.getContext().get(Context.X_OG_OBJECT_SIZE));
    }

    protected int getContainerSuffix(final Request request) {
        final String containerSuffix = request.getContext().get(Context.X_OG_CONTAINER_SUFFIX);
        if (containerSuffix == null) {
            return -1;
        } else {
            return Integer.parseInt(containerSuffix);
        }
    }

    protected abstract void updateObjectManager(ObjectMetadata objectName);
}