/// <summary>
/// Get the partitions for a specific table
/// </summary>
/// <param name="tableName">The name of the table</param>
/// <param name="canHandleMultiplePartitions">True if the caller can handle getting multiple partitions</param>
/// <param name="sqlTree">The SQL tree that can be modified to give the user the correct partitions</param>
/// <param name="httpContext">The http context that contains user information etc.</param>
/// <returns></returns>
public virtual Task <IImmutableList <Partition> > GetPartitions(bool canHandleMultiplePartitions, PartitionsBuilder partitionsBuilder, HttpContext httpContext, PartitionOptions partitionOptions)
{
return(Task.FromResult <IImmutableList <Partition> >(ImmutableList.Create <Partition>(partitionsBuilder.NewPartition().Build())));
}
public async Task <Transport.TransportPartitionsResult> GetPartitions(bool canHandlePartitions, string sql, SqlParameters sqlParameters, HttpContext httpContext)
{
var sqlTree = _sqlParser.Parse(sql, out var errors);
foreach (var header in httpContext.Request.Headers)
{
if (header.Key.StartsWith("P_", StringComparison.OrdinalIgnoreCase))
{
var parameterName = header.Key.Substring(2);
if (header.Value.Count > 1)
{
throw new SqlErrorException("Two parameters found with the same name in the http headers.");
}
var value = header.Value.First();
var base64Value = Convert.ToBase64String(Encoding.UTF8.GetBytes(value));
//Add the parameter as base64 inline parameter
sqlTree.Statements.Insert(0, new SetVariableStatement()
{
VariableReference = new SqlParser.Expressions.VariableReference()
{
Name = parameterName
},
ScalarExpression = new Base64Literal()
{
Value = base64Value
}
});
}
}
if (errors.Count > 0)
{
throw new SqlErrorException(errors.First().Message);
}
//Apply the row level security filter on the query
await RowLevelSecurityHelper.ApplyRowLevelSecurity(sqlTree, httpContext, _metadataStore, _serviceProvider);
var schema = _sqlExecutor.GetSchema(sqlTree, sqlParameters);
//Take table name and get the partition resolver
if (!_metadataStore.TryGetTable(schema.TableName, out var table))
{
throw new SqlErrorException($"The table {schema.TableName} was not found.");
}
//Get the partitions
var discoveryService = _serviceProvider.GetService <IDiscoveryService>();
var partitionsBuilder = new PartitionsBuilder(sqlTree);
var partitions = await table.PartitionResolver.GetPartitions(canHandlePartitions, partitionsBuilder, httpContext, new PartitionOptions(_serviceProvider, discoveryService));
var partitionListBuilder = ImmutableList.CreateBuilder <Transport.TransportPartition>();
foreach (var partition in partitions)
{
List <TransportServiceLocation> locations = new List <TransportServiceLocation>();
foreach (var location in partition.Locations)
{
locations.Add(new TransportServiceLocation(location.Host, location.Tls));
}
partitionListBuilder.Add(new Transport.TransportPartition(locations, partition.SqlTree.Print()));
}
return(new Transport.TransportPartitionsResult(ConvertColumns(schema.Columns), partitionListBuilder.ToImmutable()));
}