1 | #include <type_traits> |
2 | #include <ext/scope_guard.h> |
3 | |
4 | #include <Core/Defines.h> |
5 | #include <DataTypes/DataTypeFactory.h> |
6 | #include <IO/ReadHelpers.h> |
7 | #include <IO/ReadWriteBufferFromHTTP.h> |
8 | #include <Interpreters/evaluateConstantExpression.h> |
9 | #include <Parsers/ASTFunction.h> |
10 | #include <Parsers/ASTLiteral.h> |
11 | #include <Parsers/parseQuery.h> |
12 | #include <Storages/StorageXDBC.h> |
13 | #include <TableFunctions/ITableFunction.h> |
14 | #include <TableFunctions/ITableFunctionXDBC.h> |
15 | #include <TableFunctions/TableFunctionFactory.h> |
16 | #include <Poco/Net/HTTPRequest.h> |
17 | #include <Common/Exception.h> |
18 | #include <Common/typeid_cast.h> |
19 | #include <Poco/NumberFormatter.h> |
20 | #include "registerTableFunctions.h" |
21 | |
22 | namespace DB |
23 | { |
24 | namespace ErrorCodes |
25 | { |
26 | extern const int NUMBER_OF_ARGUMENTS_DOESNT_MATCH; |
27 | extern const int UNKNOWN_EXCEPTION; |
28 | extern const int LOGICAL_ERROR; |
29 | } |
30 | |
31 | StoragePtr ITableFunctionXDBC::executeImpl(const ASTPtr & ast_function, const Context & context, const std::string & table_name) const |
32 | { |
33 | const auto & args_func = ast_function->as<ASTFunction &>(); |
34 | |
35 | if (!args_func.arguments) |
36 | throw Exception("Table function '" + getName() + "' must have arguments." , ErrorCodes::LOGICAL_ERROR); |
37 | |
38 | ASTs & args = args_func.arguments->children; |
39 | if (args.size() != 2 && args.size() != 3) |
40 | throw Exception("Table function '" + getName() + "' requires 2 or 3 arguments: " + getName() + "('DSN', table) or " + getName() |
41 | + "('DSN', schema, table)" , |
42 | ErrorCodes::NUMBER_OF_ARGUMENTS_DOESNT_MATCH); |
43 | |
44 | for (auto i = 0u; i < args.size(); ++i) |
45 | args[i] = evaluateConstantExpressionOrIdentifierAsLiteral(args[i], context); |
46 | |
47 | std::string connection_string; |
48 | std::string schema_name; |
49 | std::string remote_table_name; |
50 | |
51 | if (args.size() == 3) |
52 | { |
53 | connection_string = args[0]->as<ASTLiteral &>().value.safeGet<String>(); |
54 | schema_name = args[1]->as<ASTLiteral &>().value.safeGet<String>(); |
55 | remote_table_name = args[2]->as<ASTLiteral &>().value.safeGet<String>(); |
56 | } |
57 | else if (args.size() == 2) |
58 | { |
59 | connection_string = args[0]->as<ASTLiteral &>().value.safeGet<String>(); |
60 | remote_table_name = args[1]->as<ASTLiteral &>().value.safeGet<String>(); |
61 | } |
62 | |
63 | /* Infer external table structure */ |
64 | /// Have to const_cast, because bridges store their commands inside context |
65 | BridgeHelperPtr helper = createBridgeHelper(const_cast<Context &>(context), context.getSettingsRef().http_receive_timeout.value, connection_string); |
66 | helper->startBridgeSync(); |
67 | |
68 | Poco::URI columns_info_uri = helper->getColumnsInfoURI(); |
69 | columns_info_uri.addQueryParameter("connection_string" , connection_string); |
70 | if (!schema_name.empty()) |
71 | columns_info_uri.addQueryParameter("schema" , schema_name); |
72 | columns_info_uri.addQueryParameter("table" , remote_table_name); |
73 | |
74 | const auto use_nulls = context.getSettingsRef().external_table_functions_use_nulls; |
75 | columns_info_uri.addQueryParameter("external_table_functions_use_nulls" , |
76 | Poco::NumberFormatter::format(use_nulls)); |
77 | |
78 | ReadWriteBufferFromHTTP buf(columns_info_uri, Poco::Net::HTTPRequest::HTTP_POST, nullptr); |
79 | |
80 | std::string columns_info; |
81 | readStringBinary(columns_info, buf); |
82 | NamesAndTypesList columns = NamesAndTypesList::parse(columns_info); |
83 | |
84 | auto result = std::make_shared<StorageXDBC>(getDatabaseName(), table_name, schema_name, remote_table_name, ColumnsDescription{columns}, context, helper); |
85 | |
86 | if (!result) |
87 | throw Exception("Failed to instantiate storage from table function " + getName(), ErrorCodes::UNKNOWN_EXCEPTION); |
88 | |
89 | result->startup(); |
90 | return result; |
91 | } |
92 | |
93 | void registerTableFunctionJDBC(TableFunctionFactory & factory) |
94 | { |
95 | factory.registerFunction<TableFunctionJDBC>(); |
96 | } |
97 | |
98 | void registerTableFunctionODBC(TableFunctionFactory & factory) |
99 | { |
100 | factory.registerFunction<TableFunctionODBC>(); |
101 | } |
102 | } |
103 | |