samples/Processing/LoggerExtensions.cs

/*
 * 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.
 */

namespace Processing;

using DotPulsar;
using DotPulsar.Abstractions;
using DotPulsar.Exceptions;

public static partial class LoggerExtensions
{
    // Output Message
    public static void OutputMessage(this ILogger logger, IMessage<string> message)
    {
        var publishedOn = message.PublishTimeAsDateTime;
        var payload = message.Value();
        logger.OutputMessage(publishedOn, payload);
    }

    [LoggerMessage(EventId = 0, Level = LogLevel.Information, Message = "Received: '{payload}' published on {publishedOn}")]
    static partial void OutputMessage(this ILogger logger, DateTime publishedOn, string payload);

    // The Pulsar Client got an exception
    public static void PulsarClientException(this ILogger logger, ExceptionContext exceptionContext)
    {
        if (exceptionContext.Exception is not ChannelNotReadyException && exceptionContext.Exception is not TaskCanceledException)
            logger.PulsarClientException(exceptionContext.Exception);
    }

    [LoggerMessage(EventId = 1, Level = LogLevel.Warning, Message = "The PulsarClient got an exception")]
    static partial void PulsarClientException(this ILogger logger, Exception exception);

    // Consumer changed state
    public static void ConsumerChangedState(this ILogger logger, ConsumerStateChanged stateChanged)
    {
        var logLevel = stateChanged.ConsumerState switch
        {
            ConsumerState.Disconnected => LogLevel.Warning,
            ConsumerState.Faulted => LogLevel.Error,
            _ => LogLevel.Information
        };

        logger.ConsumerChangedState(logLevel, stateChanged.Consumer.Topic, stateChanged.ConsumerState.ToString());
    }

    [LoggerMessage(EventId = 2, Message = "The consumer for topic '{topic}' changed state to '{state}'")]
    static partial void ConsumerChangedState(this ILogger logger, LogLevel logLevel, string topic, string state);

    // Consumer lost connection
    public static ValueTask<string> ConsumerLostConnection(this ILogger logger, IConsumer consumer, ConsumerState state, CancellationToken cancellationToken)
    {
        logger.ConsumerLostConnection(consumer.Topic);
        return ValueTask.FromResult("TicketId"); // Simulating a ticket-id after sending an alert. This is optional.
    }

    [LoggerMessage(EventId = 3, Level = LogLevel.Warning, Message = "The consumer for topic '{topic}' has lost the connection")]
    static partial void ConsumerLostConnection(this ILogger logger, string topic);

    // Consumer regained connection
    public static ValueTask ConsumerRegainedConnection(this ILogger logger, IConsumer consumer, ConsumerState state, string ticketId, CancellationToken cancellationToken)
    {
        logger.ConsumerRegainedConnection(consumer.Topic);
        return ValueTask.CompletedTask; // If an alert has been opened, this is where we can close it again
    }

    [LoggerMessage(EventId = 4, Level = LogLevel.Warning, Message = "The consumer for topic '{topic}' has regained the connection")]
    static partial void ConsumerRegainedConnection(this ILogger logger, string topic);
}