xref: /freebsd/contrib/kyua/store/migrate.cpp (revision d0b2dbfa0ecf2bbc9709efc5e20baf8e4b44bbbf)
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28 
29 #include "store/migrate.hpp"
30 
31 #include <stdexcept>
32 
33 #include "store/dbtypes.hpp"
34 #include "store/exceptions.hpp"
35 #include "store/layout.hpp"
36 #include "store/metadata.hpp"
37 #include "store/read_backend.hpp"
38 #include "store/write_backend.hpp"
39 #include "utils/datetime.hpp"
40 #include "utils/env.hpp"
41 #include "utils/format/macros.hpp"
42 #include "utils/fs/exceptions.hpp"
43 #include "utils/fs/operations.hpp"
44 #include "utils/fs/path.hpp"
45 #include "utils/logging/macros.hpp"
46 #include "utils/optional.ipp"
47 #include "utils/sanity.hpp"
48 #include "utils/stream.hpp"
49 #include "utils/sqlite/database.hpp"
50 #include "utils/sqlite/exceptions.hpp"
51 #include "utils/sqlite/statement.ipp"
52 #include "utils/text/operations.hpp"
53 
54 namespace datetime = utils::datetime;
55 namespace fs = utils::fs;
56 namespace sqlite = utils::sqlite;
57 namespace text = utils::text;
58 
59 using utils::none;
60 using utils::optional;
61 
62 
63 namespace {
64 
65 
66 /// Schema version at which we switched to results files.
67 const int first_chunked_schema_version = 3;
68 
69 
70 /// Queries the schema version of the given database.
71 ///
72 /// \param file The database from which to query the schema version.
73 ///
74 /// \return The schema version number.
75 static int
76 get_schema_version(const fs::path& file)
77 {
78     sqlite::database db = store::detail::open_and_setup(
79         file, sqlite::open_readonly);
80     return store::metadata::fetch_latest(db).schema_version();
81 }
82 
83 
84 /// Performs a single migration step.
85 ///
86 /// Both action_id and old_database are little hacks to support the migration
87 /// from the historical database to chunked files.  We'd use a more generic
88 /// "replacements" map, but it's not worth it.
89 ///
90 /// \param file Database on which to apply the migration step.
91 /// \param version_from Current schema version in the database.
92 /// \param version_to Schema version to migrate to.
93 /// \param action_id If not none, replace ACTION_ID in the migration file with
94 ///     this value.
95 /// \param old_database If not none, replace OLD_DATABASE in the migration
96 ///     file with this value.
97 ///
98 /// \throw error If there is a problem applying the migration.
99 static void
100 migrate_schema_step(const fs::path& file,
101                     const int version_from,
102                     const int version_to,
103                     const optional< int64_t > action_id = none,
104                     const optional< fs::path > old_database = none)
105 {
106     LI(F("Migrating schema of %s from version %s to %s") % file % version_from
107        % version_to);
108 
109     PRE(version_to == version_from + 1);
110 
111     sqlite::database db = store::detail::open_and_setup(
112         file, sqlite::open_readwrite);
113 
114     const fs::path migration = store::detail::migration_file(version_from,
115                                                              version_to);
116 
117     std::string migration_string;
118     try {
119         migration_string = utils::read_file(migration);
120     } catch (const std::runtime_error& unused_e) {
121         throw store::error(F("Cannot read migration file '%s'") % migration);
122     }
123     if (action_id) {
124         migration_string = text::replace_all(migration_string, "@ACTION_ID@",
125                                              F("%s") % action_id.get());
126     }
127     if (old_database) {
128         migration_string = text::replace_all(migration_string, "@OLD_DATABASE@",
129                                              old_database.get().str());
130     }
131     try {
132         db.exec(migration_string);
133     } catch (const sqlite::error& e) {
134         throw store::error(F("Schema migration failed: %s") % e.what());
135     }
136 }
137 
138 
139 /// Given a historical database, chunks it up into results files.
140 ///
141 /// The given database is DELETED on success given that it will have been
142 /// split up into various different files.
143 ///
144 /// \param old_file Path to the old database.
145 static void
146 chunk_database(const fs::path& old_file)
147 {
148     PRE(get_schema_version(old_file) == first_chunked_schema_version - 1);
149 
150     LI(F("Need to split %s into per-action files") % old_file);
151 
152     sqlite::database old_db = store::detail::open_and_setup(
153         old_file, sqlite::open_readonly);
154 
155     sqlite::statement actions_stmt = old_db.create_statement(
156         "SELECT action_id, cwd FROM actions NATURAL JOIN contexts");
157 
158     sqlite::statement start_time_stmt = old_db.create_statement(
159         "SELECT test_results.start_time AS start_time "
160         "FROM test_programs "
161         "    JOIN test_cases "
162         "        ON test_programs.test_program_id == test_cases.test_program_id"
163         "    JOIN test_results "
164         "        ON test_cases.test_case_id == test_results.test_case_id "
165         "WHERE test_programs.action_id == :action_id "
166         "ORDER BY start_time LIMIT 1");
167 
168     while (actions_stmt.step()) {
169         const int64_t action_id = actions_stmt.safe_column_int64("action_id");
170         const fs::path cwd(actions_stmt.safe_column_text("cwd"));
171 
172         LI(F("Extracting action %s") % action_id);
173 
174         start_time_stmt.reset();
175         start_time_stmt.bind(":action_id", action_id);
176         if (!start_time_stmt.step()) {
177             LI(F("Skipping empty action %s") % action_id);
178             continue;
179         }
180         const datetime::timestamp start_time = store::column_timestamp(
181             start_time_stmt, "start_time");
182         start_time_stmt.step_without_results();
183 
184         const fs::path new_file = store::layout::new_db_for_migration(
185             cwd, start_time);
186         if (fs::exists(new_file)) {
187             LI(F("Skipping action because %s already exists") % new_file);
188             continue;
189         }
190 
191         LI(F("Creating %s for previous action %s") % new_file % action_id);
192 
193         try {
194             fs::mkdir_p(new_file.branch_path(), 0755);
195             sqlite::database db = store::detail::open_and_setup(
196                 new_file, sqlite::open_readwrite | sqlite::open_create);
197             store::detail::initialize(db);
198             db.close();
199             migrate_schema_step(new_file,
200                                 first_chunked_schema_version - 1,
201                                 first_chunked_schema_version,
202                                 utils::make_optional(action_id),
203                                 utils::make_optional(old_file));
204         } catch (...) {
205             // TODO(jmmv): Handle this better.
206             fs::unlink(new_file);
207         }
208     }
209 
210     fs::unlink(old_file);
211 }
212 
213 
214 }  // anonymous namespace
215 
216 
217 /// Calculates the path to a schema migration file.
218 ///
219 /// \param version_from The version from which the database is being upgraded.
220 /// \param version_to The version to which the database is being upgraded.
221 ///
222 /// \return The path to the installed migrate_vX_vY.sql file.
223 fs::path
224 store::detail::migration_file(const int version_from, const int version_to)
225 {
226     return fs::path(utils::getenv_with_default("KYUA_STOREDIR", KYUA_STOREDIR))
227         / (F("migrate_v%s_v%s.sql") % version_from % version_to);
228 }
229 
230 
231 /// Backs up a database for schema migration purposes.
232 ///
233 /// \todo We should probably use the SQLite backup API instead of doing a raw
234 /// file copy.  We issue our backup call with the database already open, but
235 /// because it is quiescent, it's OK to do so.
236 ///
237 /// \param source Location of the database to be backed up.
238 /// \param old_version Version of the database's CURRENT schema, used to
239 ///     determine the name of the backup file.
240 ///
241 /// \throw error If there is a problem during the backup.
242 void
243 store::detail::backup_database(const fs::path& source, const int old_version)
244 {
245     const fs::path target(F("%s.v%s.backup") % source.str() % old_version);
246 
247     LI(F("Backing up database %s to %s") % source % target);
248     try {
249         fs::copy(source, target);
250     } catch (const fs::error& e) {
251         throw store::error(e.what());
252     }
253 }
254 
255 
256 /// Migrates the schema of a database to the current version.
257 ///
258 /// The algorithm implemented here performs a migration step for every
259 /// intermediate version between the schema version in the database to the
260 /// version implemented in this file.  This should permit upgrades from
261 /// arbitrary old databases.
262 ///
263 /// \param file The database whose schema to upgrade.
264 ///
265 /// \throw error If there is a problem with the migration.
266 void
267 store::migrate_schema(const utils::fs::path& file)
268 {
269     const int version_from = get_schema_version(file);
270     const int version_to = detail::current_schema_version;
271     if (version_from == version_to) {
272         throw error(F("Database already at schema version %s; migration not "
273                       "needed") % version_from);
274     } else if (version_from > version_to) {
275         throw error(F("Database at schema version %s, which is newer than the "
276                       "supported version %s") % version_from % version_to);
277     }
278 
279     detail::backup_database(file, version_from);
280 
281     int i;
282     for (i = version_from; i < first_chunked_schema_version - 1; ++i) {
283         migrate_schema_step(file, i, i + 1);
284     }
285     chunk_database(file);
286     INV(version_to == first_chunked_schema_version);
287 }
288