1#include <iomanip>
2#include <thread>
3#include <future>
4
5#include <Common/ThreadPool.h>
6
7#include <Poco/DirectoryIterator.h>
8#include <Poco/FileStream.h>
9
10#include <Parsers/ParserCreateQuery.h>
11#include <Parsers/ASTCreateQuery.h>
12#include <Parsers/parseQuery.h>
13
14#include <Interpreters/InterpreterCreateQuery.h>
15#include <Interpreters/Context.h>
16#include <Interpreters/loadMetadata.h>
17
18#include <Databases/DatabaseOrdinary.h>
19
20#include <IO/ReadBufferFromFile.h>
21#include <IO/ReadHelpers.h>
22#include <Common/escapeForFileName.h>
23
24#include <Common/Stopwatch.h>
25#include <Common/typeid_cast.h>
26
27
28namespace DB
29{
30
31static void executeCreateQuery(
32 const String & query,
33 Context & context,
34 const String & database,
35 const String & file_name,
36 bool has_force_restore_data_flag)
37{
38 ParserCreateQuery parser;
39 ASTPtr ast = parseQuery(parser, query.data(), query.data() + query.size(), "in file " + file_name, 0);
40
41 auto & ast_create_query = ast->as<ASTCreateQuery &>();
42 ast_create_query.attach = true;
43 ast_create_query.database = database;
44
45 InterpreterCreateQuery interpreter(ast, context);
46 interpreter.setInternal(true);
47 interpreter.setForceRestoreData(has_force_restore_data_flag);
48 interpreter.execute();
49}
50
51
52static void loadDatabase(
53 Context & context,
54 const String & database,
55 const String & database_path,
56 bool force_restore_data)
57{
58 /// There may exist .sql file with database creation statement.
59 /// Or, if it is absent, then database with default engine is created.
60
61 String database_attach_query;
62 String database_metadata_file = database_path + ".sql";
63
64 if (Poco::File(database_metadata_file).exists())
65 {
66 ReadBufferFromFile in(database_metadata_file, 1024);
67 readStringUntilEOF(database_attach_query, in);
68 }
69 else
70 database_attach_query = "ATTACH DATABASE " + backQuoteIfNeed(database);
71
72 executeCreateQuery(database_attach_query, context, database,
73 database_metadata_file, force_restore_data);
74}
75
76
77#define SYSTEM_DATABASE "system"
78
79
80void loadMetadata(Context & context)
81{
82 String path = context.getPath() + "metadata";
83
84 /** There may exist 'force_restore_data' file, that means,
85 * skip safety threshold on difference of data parts while initializing tables.
86 * This file is deleted after successful loading of tables.
87 * (flag is "one-shot")
88 */
89 Poco::File force_restore_data_flag_file(context.getFlagsPath() + "force_restore_data");
90 bool has_force_restore_data_flag = force_restore_data_flag_file.exists();
91
92 /// Loop over databases.
93 std::map<String, String> databases;
94 Poco::DirectoryIterator dir_end;
95 for (Poco::DirectoryIterator it(path); it != dir_end; ++it)
96 {
97 if (!it->isDirectory())
98 continue;
99
100 /// For '.svn', '.gitignore' directory and similar.
101 if (it.name().at(0) == '.')
102 continue;
103
104 if (it.name() == SYSTEM_DATABASE)
105 continue;
106
107 databases.emplace(unescapeForFileName(it.name()), it.path().toString());
108 }
109
110 for (const auto & [name, db_path] : databases)
111 loadDatabase(context, name, db_path, has_force_restore_data_flag);
112
113 if (has_force_restore_data_flag)
114 {
115 try
116 {
117 force_restore_data_flag_file.remove();
118 }
119 catch (...)
120 {
121 tryLogCurrentException("Load metadata", "Can't remove force restore file to enable data santity checks");
122 }
123 }
124}
125
126
127void loadMetadataSystem(Context & context)
128{
129 String path = context.getPath() + "metadata/" SYSTEM_DATABASE;
130 if (Poco::File(path).exists())
131 {
132 /// 'has_force_restore_data_flag' is true, to not fail on loading query_log table, if it is corrupted.
133 loadDatabase(context, SYSTEM_DATABASE, path, true);
134 }
135 else
136 {
137 /// Initialize system database manually
138 String global_path = context.getPath();
139 Poco::File(global_path + "data/" SYSTEM_DATABASE).createDirectories();
140 Poco::File(global_path + "metadata/" SYSTEM_DATABASE).createDirectories();
141
142 auto system_database = std::make_shared<DatabaseOrdinary>(SYSTEM_DATABASE, global_path + "metadata/" SYSTEM_DATABASE, context);
143 context.addDatabase(SYSTEM_DATABASE, system_database);
144 }
145
146}
147
148}
149