Using Microsoft.Extensions.Compliance.Redaction

[Matthew-Wise]

Hi all,

I wasn't sure how to categorize this so general it is. so I am trying to use Microsoft.Extensions.Compliance.Redaction along with LoggerMessage - https://learn.microsoft.com/en-us/dotnet/core/extensions/high-performance-logging

However when using attributes on my models to redact log properties, they are completely missing when looking at my logs instead of been encrypted using the HMAC redactor, the eraser one also removes the property label and does not log a blank message but that's much of a muchness.

I am not sure where the bug lies? To fix it but I do have a workaround for now a RedactionProcessor based of the MyRedactionProcessor in this code base (happy to PR this if you would like it)

My current work around is a RedactionLogProcessor, below. I also have a very similar Trace version.

Thanks
Matt

using System.Collections;
using Microsoft.Extensions.Compliance.Classification;
using Microsoft.Extensions.Compliance.Redaction;
using Microsoft.Extensions.Options;
using OpenTelemetry;
using OpenTelemetry.Logs;

namespace Logging.Processors;

public class RedactionLogProcessor : BaseProcessor<LogRecord>
{
    private readonly Dictionary<string, DataClassification> _redactions;
    private readonly IRedactorProvider _redactionProvider;

    public RedactionLogProcessor(IOptions<LoggingSettings> options, IRedactorProvider redactorProvider)
    {
        _redactions = options.Value.Redactions;
        _redactionProvider = redactorProvider;
    }

    public override void OnEnd(LogRecord data)
    {
        if (data.Attributes is null) return;
        data.Attributes = new RedactionLogEnumerator(data.Attributes, _redactions, _redactionProvider);
    }

    private sealed class RedactionLogEnumerator : IReadOnlyList<KeyValuePair<string, object?>>
    {
        private readonly IReadOnlyList<KeyValuePair<string, object?>> _state;
        private readonly Dictionary<string, DataClassification> _redactions;
        private readonly IRedactorProvider _redactionProvider;

        public RedactionLogEnumerator(IReadOnlyList<KeyValuePair<string, object?>> state,
            Dictionary<string, DataClassification> redactions, IRedactorProvider redactionProvider)
        {
            _state = state;
            _redactions = redactions;
            _redactionProvider = redactionProvider;
        }

        public IEnumerator<KeyValuePair<string, object?>> GetEnumerator()
        {
            for (var i = 0; i < Count; i++)
            {
                yield return this[i];
            }
        }

        IEnumerator IEnumerable.GetEnumerator() => GetEnumerator();

        public int Count => _state.Count;

        public KeyValuePair<string, object?> this[int index]
        {

            get
            {
                var item = _state[index];
                if (!_redactions.TryGetValue(item.Key, out var classification))
                {
                    return item;
                }

                var redactor = _redactionProvider.GetRedactor(new DataClassificationSet(classification));
                return new KeyValuePair<string, object?>(item.Key, redactor.Redact(item.Value));
            }
        }
    }
}