private TableQuery<LogEntity> MapQuery(AzureNLogQueryDefinition originalQuery)
{
var query = new TableQuery<LogEntity>();
var filters = new[]
{
this.GetPartitionKeyFilter(originalQuery), this.GetMinDateFilter(originalQuery),
this.GetMaxDateFilter(originalQuery), this.GetLevelFilter(originalQuery)
}
.Where(f => !string.IsNullOrWhiteSpace(f))
.ToArray();
if (!filters.Any())
{
return query;
}
var querySt = filters[0];
for (var i = 1; i < filters.Length; i++)
{
querySt = TableQuery.CombineFilters(querySt, TableOperators.And, filters[i]);
}
return query.Where(querySt);
}
private string GetMinDateFilter(AzureNLogQueryDefinition originalQuery)
{
if (originalQuery.MinimumDate == null)
{
return null;
}
return TableQuery.GenerateFilterCondition(nameof(LogEntity.RowKey), QueryComparisons.GreaterThanOrEqual,
this.StringifyDate(originalQuery.MinimumDate.Value));
}
public async Task<IEnumerable<LogEntity>> GetLogsAsync(AzureNLogQueryDefinition query, int? maxResults)
{
var queryBody = this.MapQuery(query);
var table = this.GetTable();
var results = new List<LogEntity>();
TableContinuationToken token = null;
do
{
var seg = await table.ExecuteQuerySegmentedAsync(queryBody, token);
token = seg.ContinuationToken;
results.AddRange(seg.Results);
} while (token != null && results.Count < (maxResults ?? int.MaxValue));
return results.OrderByDescending(r => r.LogTimeStamp).Take(maxResults ?? int.MaxValue);
}
private string GetMaxDateFilter(AzureNLogQueryDefinition originalQuery)
{
return originalQuery.MaximumDate == null
? null
: TableQuery.GenerateFilterCondition(nameof(LogEntity.RowKey), QueryComparisons.LessThanOrEqual,
this.StringifyDate(originalQuery.MaximumDate.Value));
}
private string GetPartitionKeyFilter(AzureNLogQueryDefinition originalQuery)
{
return string.IsNullOrWhiteSpace(originalQuery.PartitionKey)
? null
: this.GetStringStartsWithQuery(nameof(LogEntity.PartitionKey), originalQuery.PartitionKey);
}
public IEnumerable<LogEntity> GetLogs(AzureNLogQueryDefinition query)
{
var queryBody = this.MapQuery(query);
return this.GetTable().ExecuteQuery(queryBody);
}
private string GetLevelFilter(AzureNLogQueryDefinition originalQuery)
{
return originalQuery.Level == null
? null
: TableQuery.GenerateFilterCondition(nameof(LogEntity.Level), QueryComparisons.Equal, originalQuery.Level);
}
