public async Task ReindexInstancesAsync()

in src/Microsoft.Health.Dicom.Operations/Indexing/ReindexDurableFunction.Orchestration.cs [34:103]
56 lines of code
5 McCabe index (conditional complexity)

        public async Task ReindexInstancesAsync(
            [OrchestrationTrigger] IDurableOrchestrationContext context,
            ILogger logger)
        {
            EnsureArg.IsNotNull(context, nameof(context));

            logger = context.CreateReplaySafeLogger(logger);
            ReindexInput input = context.GetInput<ReindexInput>();

            // The ID should be a GUID as generated by the trigger, but we'll assert here just to make sure!
            if (!context.HasInstanceGuid())
            {
                return;
            }

            // Fetch the set of query tags that require re-indexing
            IReadOnlyList<ExtendedQueryTagStoreEntry> queryTags = await GetOperationQueryTagsAsync(context, input);
            logger.LogInformation(
                "Found {Count} extended query tag paths to re-index {{{TagPaths}}}.",
                queryTags.Count,
                string.Join(", ", queryTags.Select(x => x.Path)));

            List<int> queryTagKeys = queryTags.Select(x => x.Key).ToList();
            if (queryTags.Count > 0)
            {
                IReadOnlyList<WatermarkRange> batches = await context.CallActivityWithRetryAsync<IReadOnlyList<WatermarkRange>>(
                    nameof(GetInstanceBatchesV2Async),
                    _options.ActivityRetryOptions,
                    BatchCreationArguments.FromOptions(input.Completed?.Start - 1, _options));

                if (batches.Count > 0)
                {
                    // Note that batches are in reverse order because we start from the highest watermark
                    var batchRange = new WatermarkRange(batches[^1].Start, batches[0].End);

                    logger.LogInformation("Beginning to re-index the range {Range}.", batchRange);
                    await Task.WhenAll(batches
                        .Select(x => context.CallActivityWithRetryAsync(
                            nameof(ReindexBatchV2Async),
                            _options.ActivityRetryOptions,
                            ReindexBatchArguments.FromOptions(queryTags, x, _options))));

                    // Create a new orchestration with the same instance ID to process the remaining data
                    logger.LogInformation("Completed re-indexing the range {Range}. Continuing with new execution...", batchRange);

                    WatermarkRange completed = input.Completed.HasValue
                        ? new WatermarkRange(batchRange.Start, input.Completed.Value.End)
                        : batchRange;

                    context.ContinueAsNew(new ReindexInput { QueryTagKeys = queryTagKeys, Completed = completed });
                }
                else
                {
                    IReadOnlyList<int> completed = await context.CallActivityWithRetryAsync<IReadOnlyList<int>>(
                        nameof(CompleteReindexingAsync),
                        _options.ActivityRetryOptions,
                        queryTagKeys);

                    logger.LogInformation(
                        "Completed re-indexing for the following extended query tags {{{QueryTagKeys}}}.",
                        string.Join(", ", completed));
                }
            }
            else
            {
                logger.LogWarning(
                    "Could not find any query tags for the re-indexing operation '{OperationId}'.",
                    context.InstanceId);
            }
        }