org.eclipse.ditto.connectivity.service.messaging.httppush.HttpPushRoundTripSignalsValidator Maven / Gradle / Ivy

/*
 * Copyright (c) 2021 Contributors to the Eclipse Foundation
 *
 * See the NOTICE file(s) distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License 2.0 which is available at
 * http://www.eclipse.org/legal/epl-2.0
 *
 * SPDX-License-Identifier: EPL-2.0
 */
package org.eclipse.ditto.connectivity.service.messaging.httppush;

import static org.eclipse.ditto.base.model.common.ConditionChecker.checkNotNull;

import java.util.function.BiConsumer;

import javax.annotation.concurrent.NotThreadSafe;

import org.eclipse.ditto.base.model.common.HttpStatus;
import org.eclipse.ditto.base.model.headers.DittoHeaderDefinition;
import org.eclipse.ditto.base.model.headers.DittoHeaders;
import org.eclipse.ditto.base.model.signals.UnsupportedSignalException;
import org.eclipse.ditto.base.model.signals.commands.Command;
import org.eclipse.ditto.base.model.signals.commands.CommandResponse;
import org.eclipse.ditto.connectivity.api.messaging.monitoring.logs.LogEntryFactory;
import org.eclipse.ditto.connectivity.model.ConnectionIdInvalidException;
import org.eclipse.ditto.connectivity.model.LogEntry;
import org.eclipse.ditto.connectivity.service.messaging.monitoring.logs.ConnectionLogger;
import org.eclipse.ditto.internal.models.signal.correlation.CommandAndCommandResponseMatchingValidator;
import org.eclipse.ditto.internal.models.signal.correlation.MatchingValidationResult;
import org.eclipse.ditto.internal.utils.akka.logging.DittoLogger;
import org.eclipse.ditto.internal.utils.akka.logging.DittoLoggerFactory;

/**
 * Validates that a specified {@link Command} and {@link CommandResponse} are associated with each other, i.e. that the
 * command response correlates to a command.
 * 
 * Both signals correlate if
 * 

 *     their correlation IDs match,
 *     their signal types match and
 *     their entity IDs match.
 * 
 * 
 * 
 * If any of the above evaluates to {@code false} a {@link UnsupportedSignalException} is thrown with a detail
 * message describing the cause.
 * Furthermore the exception gets logged for the command response via {@link ConnectionLogger#logEntry(LogEntry)}.
 * 
 */
@NotThreadSafe
final class HttpPushRoundTripSignalsValidator implements BiConsumer, CommandResponse> {

    private static final DittoLogger LOGGER = DittoLoggerFactory.getLogger(HttpPushRoundTripSignalsValidator.class);

    private final ConnectionLogger connectionLogger;
    private final CommandAndCommandResponseMatchingValidator validator;

    private HttpPushRoundTripSignalsValidator(final ConnectionLogger connectionLogger) {
        this.connectionLogger = connectionLogger;
        validator = CommandAndCommandResponseMatchingValidator.getInstance();
    }

    static HttpPushRoundTripSignalsValidator newInstance(final ConnectionLogger connectionLogger) {
        return new HttpPushRoundTripSignalsValidator(checkNotNull(connectionLogger, "connectionLogger"));
    }

    @Override
    public void accept(final Command command, final CommandResponse commandResponse) {
        final var validationResult = tryToValidate(command, commandResponse);
        if (!validationResult.isSuccess()) {
            final var failure = validationResult.asFailureOrThrow();
            final var detailMessage = failure.getDetailMessage();
            connectionLogger.logEntry(LogEntryFactory.getLogEntryForFailedCommandResponseRoundTrip(command,
                    commandResponse,
                    detailMessage));
            throw newUnsupportedSignalException(command, commandResponse, detailMessage);
        }
    }

    private MatchingValidationResult tryToValidate(final Command command, final CommandResponse commandResponse) {
        try {
            return validator.apply(command, commandResponse);
        } catch (final ConnectionIdInvalidException e) {

            /*
             * In this case an invalid connection ID is no problem at all.
             * As the ConnectionLogger is already known, a log entry can be
             * directly added.
             * Besides, an invalid connection ID in response headers is very
             * unlikely as it gets set by Ditto itself.
             */
            LOGGER.withCorrelationId(command)
                    .warn("Headers of command response contain an invalid connection ID: {}", e.getMessage());
            final var headersWithoutConnectionId = DittoHeaders.newBuilder(commandResponse.getDittoHeaders())
                    .removeHeader(DittoHeaderDefinition.CONNECTION_ID.getKey())
                    .build();
            return validator.apply(command, commandResponse.setDittoHeaders(headersWithoutConnectionId));
        }
    }

    private static UnsupportedSignalException newUnsupportedSignalException(final Command command,
            final CommandResponse commandResponse,
            final String detailMessage) {

        return UnsupportedSignalException.newBuilder(commandResponse.getType())
                .httpStatus(HttpStatus.UNPROCESSABLE_ENTITY)
                .message(detailMessage)
                .dittoHeaders(command.getDittoHeaders())
                .build();
    }

}