Author: Manos Pitsidianakis [manos@pitsidianak.is]

Hash: d5fc2d8e75cc1294cd6f0d4ea5e8b97f005eda79

Timestamp: Fri, 05 May 2023 09:29:21 +0000 (1 year ago)

+307 -61 +/-11 browse

core: add database migrations

1	diff --git a/.github/workflows/test.yaml b/.github/workflows/test.yaml
2	index 086823d..4958e63 100644
3	--- a/.github/workflows/test.yaml
4	+++ b/.github/workflows/test.yaml
5	@@ -76,16 +76,20 @@ jobs:
6	- name: cargo test
7	if: success() || failure() # always run even if other steps fail, except when cancelled <https://stackoverflow.com/questions/58858429/how-to-run-a-github-actions-step-even-if-the-previous-step-fails-while-still-f>
8	run: |
9	- cargo test --all --no-fail-fast --all-features
10	+ cargo test --all --no-fail-fast --all-features
11	- name: cargo-sort
12	- if: success() || failure() # always run even if other steps fail, except when cancelled <https://stackoverflow.com/questions/58858429/how-to-run-a-github-actions-step-even-if-the-previous-step-fails-while-still-f>
13	+ if: success() || failure()
14	run: |
15	cargo sort --check
16	- name: rustfmt
17	- if: success() || failure() # always run even if other steps fail, except when cancelled <https://stackoverflow.com/questions/58858429/how-to-run-a-github-actions-step-even-if-the-previous-step-fails-while-still-f>
18	+ if: success() || failure()
19	run: |
20	cargo fmt --check --all
21	- name: clippy
22	- if: success() || failure() # always run even if other steps fail, except when cancelled <https://stackoverflow.com/questions/58858429/how-to-run-a-github-actions-step-even-if-the-previous-step-fails-while-still-f>
23	+ if: success() || failure()
24	run: |
25	cargo clippy --no-deps --all-features --all --tests --examples --benches --bins
26	+ - name: rustdoc
27	+ if: success() || failure()
28	+ run: |
29	+ make rustdoc
30	diff --git a/core/build.rs b/core/build.rs
31	index 77a3159..23a9bcd 100644
32	--- a/core/build.rs
33	+++ b/core/build.rs
34	@@ -18,45 +18,141 @@
35	*/
36
37	use std::{
38	+ fs::{metadata, read_dir, OpenOptions},
39	+ io,
40	io::Write,
41	+ path::Path,
42	process::{Command, Stdio},
43	};
44
45	+ // Source: https://stackoverflow.com/a/64535181
46	+ fn is_output_file_outdated<P1, P2>(input: P1, output: P2) -> io::Result<bool>
47	+ where
48	+ P1: AsRef<Path>,
49	+ P2: AsRef<Path>,
50	+ {
51	+ let out_meta = metadata(output);
52	+ if let Ok(meta) = out_meta {
53	+ let output_mtime = meta.modified()?;
54	+
55	+ // if input file is more recent than our output, we are outdated
56	+ let input_meta = metadata(input)?;
57	+ let input_mtime = input_meta.modified()?;
58	+
59	+ Ok(input_mtime > output_mtime)
60	+ } else {
61	+ // output file not found, we are outdated
62	+ Ok(true)
63	+ }
64	+ }
65	+
66	fn main() {
67	+ println!("cargo:rerun-if-changed=migrations");
68	println!("cargo:rerun-if-changed=src/schema.sql.m4");
69
70	- let output = Command::new("m4")
71	- .arg("./src/schema.sql.m4")
72	- .output()
73	- .unwrap();
74	- if String::from_utf8_lossy(&output.stdout).trim().is_empty() {
75	- panic!(
76	- "m4 output is empty. stderr was {}",
77	- String::from_utf8_lossy(&output.stderr)
78	+ if is_output_file_outdated("src/schema.sql.m4", "src/schema.sql").unwrap() {
79	+ let output = Command::new("m4")
80	+ .arg("./src/schema.sql.m4")
81	+ .output()
82	+ .unwrap();
83	+ if String::from_utf8_lossy(&output.stdout).trim().is_empty() {
84	+ panic!(
85	+ "m4 output is empty. stderr was {}",
86	+ String::from_utf8_lossy(&output.stderr)
87	+ );
88	+ }
89	+ let mut verify = Command::new("sqlite3")
90	+ .stdin(Stdio::piped())
91	+ .stdout(Stdio::piped())
92	+ .stderr(Stdio::piped())
93	+ .spawn()
94	+ .unwrap();
95	+ println!(
96	+ "Verifying by creating an in-memory database in sqlite3 and feeding it the output \
97	+ schema."
98	);
99	+ verify
100	+ .stdin
101	+ .take()
102	+ .unwrap()
103	+ .write_all(&output.stdout)
104	+ .unwrap();
105	+ let exit = verify.wait_with_output().unwrap();
106	+ if !exit.status.success() {
107	+ panic!(
108	+ "sqlite3 could not read SQL schema: {}",
109	+ String::from_utf8_lossy(&exit.stdout)
110	+ );
111	+ }
112	+ let mut file = std::fs::File::create("./src/schema.sql").unwrap();
113	+ file.write_all(&output.stdout).unwrap();
114	}
115	- let mut verify = Command::new("sqlite3")
116	- .stdin(Stdio::piped())
117	- .stdout(Stdio::piped())
118	- .stderr(Stdio::piped())
119	- .spawn()
120	- .unwrap();
121	- println!(
122	- "Verifying by creating an in-memory database in sqlite3 and feeding it the output schema."
123	- );
124	- verify
125	- .stdin
126	- .take()
127	- .unwrap()
128	- .write_all(&output.stdout)
129	- .unwrap();
130	- let exit = verify.wait_with_output().unwrap();
131	- if !exit.status.success() {
132	- panic!(
133	- "sqlite3 could not read SQL schema: {}",
134	- String::from_utf8_lossy(&exit.stdout)
135	- );
136	+
137	+ const MIGRATION_RS: &str = "src/migrations.rs.inc";
138	+
139	+ let mut regen = false;
140	+ let mut paths = vec![];
141	+ let mut undo_paths = vec![];
142	+ for entry in read_dir("migrations").unwrap() {
143	+ let entry = entry.unwrap();
144	+ let path = entry.path();
145	+ if path.is_dir() || path.extension().map(|os| os.to_str().unwrap()) != Some("sql") {
146	+ continue;
147	+ }
148	+ if is_output_file_outdated(&path, MIGRATION_RS).unwrap() {
149	+ regen = true;
150	+ }
151	+ if path
152	+ .file_name()
153	+ .unwrap()
154	+ .to_str()
155	+ .unwrap()
156	+ .ends_with("undo.sql")
157	+ {
158	+ undo_paths.push(path);
159	+ } else {
160	+ paths.push(path);
161	+ }
162	+ }
163	+
164	+ if regen {
165	+ paths.sort();
166	+ undo_paths.sort();
167	+ let mut migr_rs = OpenOptions::new()
168	+ .write(true)
169	+ .create(true)
170	+ .truncate(true)
171	+ .open(MIGRATION_RS)
172	+ .unwrap();
173	+ migr_rs
174	+ .write_all(b"\n//(user_version, redo sql, undo sql\n&[")
175	+ .unwrap();
176	+ for (p, u) in paths.iter().zip(undo_paths.iter()) {
177	+ // This should be a number string, padded with 2 zeros if it's less than 3
178	+ // digits. e.g. 001, \d{3}
179	+ let num = p.file_stem().unwrap().to_str().unwrap();
180	+ if !u.file_name().unwrap().to_str().unwrap().starts_with(num) {
181	+ panic!("Undo file {u:?} should match with {p:?}");
182	+ }
183	+ if num.parse::<u32>().is_err() {
184	+ panic!("Migration file {p:?} should start with a number");
185	+ }
186	+ migr_rs.write_all(b"(").unwrap();
187	+ migr_rs
188	+ .write_all(num.trim_start_matches('0').as_bytes())
189	+ .unwrap();
190	+ migr_rs.write_all(b",\"").unwrap();
191	+
192	+ migr_rs
193	+ .write_all(std::fs::read_to_string(p).unwrap().as_bytes())
194	+ .unwrap();
195	+ migr_rs.write_all(b"\",\"").unwrap();
196	+ migr_rs
197	+ .write_all(std::fs::read_to_string(u).unwrap().as_bytes())
198	+ .unwrap();
199	+ migr_rs.write_all(b"\"),").unwrap();
200	+ }
201	+ migr_rs.write_all(b"]").unwrap();
202	+ migr_rs.flush().unwrap();
203	}
204	- let mut file = std::fs::File::create("./src/schema.sql").unwrap();
205	- file.write_all(&output.stdout).unwrap();
206	}
207	diff --git a/core/migrations/001.sql b/core/migrations/001.sql
208	new file mode 100644
209	index 0000000..a62617c
210	--- /dev/null
211	+++ b/core/migrations/001.sql
212	@@ -0,0 +1,4 @@
213	+ PRAGMA foreign_keys=ON;
214	+ BEGIN;
215	+ ALTER TABLE templates RENAME TO template;
216	+ COMMIT;
217	diff --git a/core/migrations/001.undo.sql b/core/migrations/001.undo.sql
218	new file mode 100644
219	index 0000000..86fe8ac
220	--- /dev/null
221	+++ b/core/migrations/001.undo.sql
222	@@ -0,0 +1,4 @@
223	+ PRAGMA foreign_keys=ON;
224	+ BEGIN;
225	+ ALTER TABLE template RENAME TO templates;
226	+ COMMIT;
227	diff --git a/core/src/connection.rs b/core/src/connection.rs
228	index ce550ef..235e878 100644
229	--- a/core/src/connection.rs
230	+++ b/core/src/connection.rs
231	@@ -91,7 +91,7 @@ fn user_authorizer_callback(
232	table_name: "post" | "queue" | "candidate_subscription" | "subscription" | "account",
233	}
234	| AuthAction::Update {
235	- table_name: "candidate_subscription" | "templates",
236	+ table_name: "candidate_subscription" | "template",
237	column_name: "accepted" | "last_modified" | "verified" | "address",
238	}
239	| AuthAction::Update {
240	@@ -129,6 +129,10 @@ impl Connection {
241	/// ```
242	pub const SCHEMA: &str = include_str!("./schema.sql");
243
244	+ /// Database migrations.
245	+ pub const MIGRATIONS: &'static [(u32, &'static str, &'static str)] =
246	+ include!("./migrations.rs.inc");
247	+
248	/// Creates a new database connection.
249	///
250	/// `Connection` supports a limited subset of operations by default (see
251	@@ -159,11 +163,68 @@ impl Connection {
252	conn.set_db_config(DbConfig::SQLITE_DBCONFIG_TRUSTED_SCHEMA, false)?;
253	conn.busy_timeout(core::time::Duration::from_millis(500))?;
254	conn.busy_handler(Some(|times: i32| -> bool { times < 5 }))?;
255	- conn.authorizer(Some(user_authorizer_callback));
256	- Ok(Self {
257	+
258	+ let mut ret = Self {
259	conf,
260	connection: conn,
261	- })
262	+ };
263	+ if let Some(&(latest, _, _)) = Self::MIGRATIONS.last() {
264	+ let version = ret.schema_version()?;
265	+ trace!(
266	+ "SQLITE user_version PRAGMA returned {version}. Most recent migration is {latest}."
267	+ );
268	+ if version < latest {
269	+ info!("Updating database schema from version {version} to {latest}...");
270	+ }
271	+ ret.migrate(version, latest)?;
272	+ }
273	+
274	+ ret.connection.authorizer(Some(user_authorizer_callback));
275	+ Ok(ret)
276	+ }
277	+
278	+ /// The version of the current schema.
279	+ pub fn schema_version(&self) -> Result<u32> {
280	+ Ok(self
281	+ .connection
282	+ .prepare("SELECT user_version FROM pragma_user_version;")?
283	+ .query_row([], |row| {
284	+ let v: u32 = row.get(0)?;
285	+ Ok(v)
286	+ })?)
287	+ }
288	+
289	+ /// Migrate from version `from` to `to`.
290	+ ///
291	+ /// See [Self::MIGRATIONS].
292	+ pub fn migrate(&mut self, mut from: u32, to: u32) -> Result<()> {
293	+ if from == to {
294	+ return Ok(());
295	+ }
296	+
297	+ let undo = from > to;
298	+ let tx = self.connection.transaction()?;
299	+
300	+ while from != to {
301	+ log::trace!(
302	+ "exec migration from {from} to {to}, type: {}do",
303	+ if undo { "un " } else { "re" }
304	+ );
305	+ if undo {
306	+ trace!("{}", Self::MIGRATIONS[from as usize].2);
307	+ tx.execute(Self::MIGRATIONS[from as usize].2, [])?;
308	+ from -= 1;
309	+ } else {
310	+ trace!("{}", Self::MIGRATIONS[from as usize].1);
311	+ tx.execute(Self::MIGRATIONS[from as usize].1, [])?;
312	+ from += 1;
313	+ }
314	+ }
315	+ tx.pragma_update(None, "user_version", Self::MIGRATIONS[to as usize - 1].0)?;
316	+
317	+ tx.commit()?;
318	+
319	+ Ok(())
320	}
321
322	/// Removes operational limits from this connection. (see
323	@@ -211,8 +272,22 @@ impl Connection {
324	let mut stdin = child.stdin.take().unwrap();
325	std::thread::spawn(move || {
326	stdin
327	- .write_all(include_bytes!("./schema.sql"))
328	+ .write_all(Self::SCHEMA.as_bytes())
329	.expect("failed to write to stdin");
330	+ if !Self::MIGRATIONS.is_empty() {
331	+ stdin
332	+ .write_all(b"\nPRAGMA user_version = ")
333	+ .expect("failed to write to stdin");
334	+ stdin
335	+ .write_all(
336	+ Self::MIGRATIONS[Self::MIGRATIONS.len() - 1]
337	+ .0
338	+ .to_string()
339	+ .as_bytes(),
340	+ )
341	+ .expect("failed to write to stdin");
342	+ stdin.write_all(b";").expect("failed to write to stdin");
343	+ }
344	stdin.flush().expect("could not flush stdin");
345	});
346	let output = child.wait_with_output()?;
347	diff --git a/core/src/mail.rs b/core/src/mail.rs
348	index 612261f..c482c38 100644
349	--- a/core/src/mail.rs
350	+++ b/core/src/mail.rs
351	@@ -17,8 +17,9 @@
352	* along with this program. If not, see <https://www.gnu.org/licenses/>.
353	*/
354
355	- //! Types for processing new posts: [`PostFilter`](message_filters::PostFilter),
356	- //! [`ListContext`], [`MailJob`] and [`PostAction`].
357	+ //! Types for processing new posts:
358	+ //! [`PostFilter`](crate::message_filters::PostFilter), [`ListContext`],
359	+ //! [`MailJob`] and [`PostAction`].
360
361	use log::trace;
362	use melib::Address;
363	@@ -28,7 +29,7 @@ use crate::{
364	DbVal,
365	};
366	/// Post action returned from a list's
367	- /// [`PostFilter`](message_filters::PostFilter) stack.
368	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
369	#[derive(Debug)]
370	pub enum PostAction {
371	/// Add to `hold` queue.
372	@@ -47,8 +48,8 @@ pub enum PostAction {
373	},
374	}
375
376	- /// List context passed to a list's [`PostFilter`](message_filters::PostFilter)
377	- /// stack.
378	+ /// List context passed to a list's
379	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
380	#[derive(Debug)]
381	pub struct ListContext<'list> {
382	/// Which mailing list a post was addressed to.
383	@@ -62,12 +63,12 @@ pub struct ListContext<'list> {
384	/// The mailing list subscription policy.
385	pub subscription_policy: Option<DbVal<SubscriptionPolicy>>,
386	/// The scheduled jobs added by each filter in a list's
387	- /// [`PostFilter`](message_filters::PostFilter) stack.
388	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
389	pub scheduled_jobs: Vec<MailJob>,
390	}
391
392	/// Post to be considered by the list's
393	- /// [`PostFilter`](message_filters::PostFilter) stack.
394	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
395	pub struct PostEntry {
396	/// `From` address of post.
397	pub from: Address,
398	@@ -76,7 +77,7 @@ pub struct PostEntry {
399	/// `To` addresses of post.
400	pub to: Vec<Address>,
401	/// Final action set by each filter in a list's
402	- /// [`PostFilter`](message_filters::PostFilter) stack.
403	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
404	pub action: PostAction,
405	}
406
407	@@ -92,7 +93,7 @@ impl core::fmt::Debug for PostEntry {
408	}
409
410	/// Scheduled jobs added to a [`ListContext`] by a list's
411	- /// [`PostFilter`](message_filters::PostFilter) stack.
412	+ /// [`PostFilter`](crate::message_filters::PostFilter) stack.
413	#[derive(Debug)]
414	pub enum MailJob {
415	/// Send post to recipients.
416	diff --git a/core/src/migrations.rs.inc b/core/src/migrations.rs.inc
417	new file mode 100644
418	index 0000000..b6ad33e
419	--- /dev/null
420	+++ b/core/src/migrations.rs.inc
421	@@ -0,0 +1,11 @@
422	+
423	+ //(user_version, redo sql, undo sql
424	+ &[(1,"PRAGMA foreign_keys=ON;
425	+ BEGIN;
426	+ ALTER TABLE templates RENAME TO template;
427	+ COMMIT;
428	+ ","PRAGMA foreign_keys=ON;
429	+ BEGIN;
430	+ ALTER TABLE template RENAME TO templates;
431	+ COMMIT;
432	+ "),]
433	\ No newline at end of file
434	diff --git a/core/src/schema.sql b/core/src/schema.sql
435	index 9c5cf75..30654a6 100644
436	--- a/core/src/schema.sql
437	+++ b/core/src/schema.sql
438	@@ -256,7 +256,7 @@ CREATE TABLE IF NOT EXISTS post (
439	created INTEGER NOT NULL DEFAULT (unixepoch())
440	);
441
442	- CREATE TABLE IF NOT EXISTS templates (
443	+ CREATE TABLE IF NOT EXISTS template (
444	pk INTEGER PRIMARY KEY NOT NULL,
445	name TEXT NOT NULL,
446	list INTEGER,
447	@@ -457,13 +457,13 @@ BEGIN
448	WHERE pk = NEW.pk;
449	END;
450
451	- -- [tag:last_modified_templates]: update last_modified on every change.
452	+ -- [tag:last_modified_template]: update last_modified on every change.
453	CREATE TRIGGER
454	- IF NOT EXISTS last_modified_templates
455	- AFTER UPDATE ON templates
456	+ IF NOT EXISTS last_modified_template
457	+ AFTER UPDATE ON template
458	FOR EACH ROW
459	WHEN NEW.last_modified != OLD.last_modified
460	BEGIN
461	- UPDATE templates SET last_modified = unixepoch()
462	+ UPDATE template SET last_modified = unixepoch()
463	WHERE pk = NEW.pk;
464	END;
465	diff --git a/core/src/schema.sql.m4 b/core/src/schema.sql.m4
466	index 3d0fa1f..0f1cee6 100644
467	--- a/core/src/schema.sql.m4
468	+++ b/core/src/schema.sql.m4
469	@@ -158,7 +158,7 @@ CREATE TABLE IF NOT EXISTS post (
470	created INTEGER NOT NULL DEFAULT (unixepoch())
471	);
472
473	- CREATE TABLE IF NOT EXISTS templates (
474	+ CREATE TABLE IF NOT EXISTS template (
475	pk INTEGER PRIMARY KEY NOT NULL,
476	name TEXT NOT NULL,
477	list INTEGER,
478	@@ -288,4 +288,4 @@ update_last_modified(`subscription_policy')
479	update_last_modified(`subscription')
480	update_last_modified(`account')
481	update_last_modified(`candidate_subscription')
482	- update_last_modified(`templates')
483	+ update_last_modified(`template')
484	diff --git a/core/src/templates.rs b/core/src/templates.rs
485	index 8617b46..31b9b24 100644
486	--- a/core/src/templates.rs
487	+++ b/core/src/templates.rs
488	@@ -216,7 +216,7 @@ impl Connection {
489	pub fn fetch_templates(&self) -> Result<Vec<DbVal<Template>>> {
490	let mut stmt = self
491	.connection
492	- .prepare("SELECT * FROM templates ORDER BY pk;")?;
493	+ .prepare("SELECT * FROM template ORDER BY pk;")?;
494	let iter = stmt.query_map(rusqlite::params![], |row| {
495	let pk = row.get("pk")?;
496	Ok(DbVal(
497	@@ -248,7 +248,7 @@ impl Connection {
498	) -> Result<Option<DbVal<Template>>> {
499	let mut stmt = self
500	.connection
501	- .prepare("SELECT * FROM templates WHERE name = ? AND list IS ?;")?;
502	+ .prepare("SELECT * FROM template WHERE name = ? AND list IS ?;")?;
503	let ret = stmt
504	.query_row(rusqlite::params![&template, &list_pk], |row| {
505	let pk = row.get("pk")?;
506	@@ -268,7 +268,7 @@ impl Connection {
507	if ret.is_none() && list_pk.is_some() {
508	let mut stmt = self
509	.connection
510	- .prepare("SELECT * FROM templates WHERE name = ? AND list IS NULL;")?;
511	+ .prepare("SELECT * FROM template WHERE name = ? AND list IS NULL;")?;
512	Ok(stmt
513	.query_row(rusqlite::params![&template], |row| {
514	let pk = row.get("pk")?;
515	@@ -293,7 +293,7 @@ impl Connection {
516	/// Insert a named template.
517	pub fn add_template(&self, template: Template) -> Result<DbVal<Template>> {
518	let mut stmt = self.connection.prepare(
519	- "INSERT INTO templates(name, list, subject, headers_json, body) VALUES(?, ?, ?, ?, ?) \
520	+ "INSERT INTO template(name, list, subject, headers_json, body) VALUES(?, ?, ?, ?, ?) \
521	RETURNING *;",
522	)?;
523	let ret = stmt
524	@@ -345,7 +345,7 @@ impl Connection {
525	pub fn remove_template(&self, template: &str, list_pk: Option<i64>) -> Result<Template> {
526	let mut stmt = self
527	.connection
528	- .prepare("DELETE FROM templates WHERE name = ? AND list IS ? RETURNING *;")?;
529	+ .prepare("DELETE FROM template WHERE name = ? AND list IS ? RETURNING *;")?;
530	let ret = stmt.query_row(rusqlite::params![&template, &list_pk], |row| {
531	Ok(Template {
532	pk: -1,
533	diff --git a/core/tests/migrations.rs b/core/tests/migrations.rs
534	new file mode 100644
535	index 0000000..84c6448
536	--- /dev/null
537	+++ b/core/tests/migrations.rs
538	@@ -0,0 +1,51 @@
539	+ /*
540	+ * This file is part of mailpot
541	+ *
542	+ * Copyright 2020 - Manos Pitsidianakis
543	+ *
544	+ * This program is free software: you can redistribute it and/or modify
545	+ * it under the terms of the GNU Affero General Public License as
546	+ * published by the Free Software Foundation, either version 3 of the
547	+ * License, or (at your option) any later version.
548	+ *
549	+ * This program is distributed in the hope that it will be useful,
550	+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
551	+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
552	+ * GNU Affero General Public License for more details.
553	+ *
554	+ * You should have received a copy of the GNU Affero General Public License
555	+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
556	+ */
557	+
558	+ use mailpot::{Configuration, Connection, SendMail};
559	+ use mailpot_tests::init_stderr_logging;
560	+ use tempfile::TempDir;
561	+
562	+ #[test]
563	+ fn test_init_empty() {
564	+ init_stderr_logging();
565	+ let tmp_dir = TempDir::new().unwrap();
566	+
567	+ let db_path = tmp_dir.path().join("mpot.db");
568	+ let config = Configuration {
569	+ send_mail: SendMail::ShellCommand("/usr/bin/false".to_string()),
570	+ db_path,
571	+ data_path: tmp_dir.path().to_path_buf(),
572	+ administrators: vec![],
573	+ };
574	+
575	+ let mut db = Connection::open_or_create_db(config).unwrap().trusted();
576	+
577	+ let migrations = Connection::MIGRATIONS;
578	+ if migrations.is_empty() {
579	+ return;
580	+ }
581	+
582	+ let version = db.schema_version().unwrap();
583	+
584	+ assert_eq!(version, migrations[migrations.len() - 1].0);
585	+
586	+ db.migrate(version, migrations[0].0).unwrap();
587	+
588	+ db.migrate(migrations[0].0, version).unwrap();
589	+ }