Commit Graph

15 Commits

Author SHA1 Message Date
Alan Guo Xiang Tan 0b947b6aab
DEV: Improve code comment about when ignored columns can be removed (#26894)
Ignored columns can only be dropped when its associated post-deploy
migration has been promoted to a regular migration. This is so because
Discourse doesn't rely on a schema file system to setup a brand new
database and thus the column information will be loaded by the
application first before the post-deploy migration runs.
2024-05-07 11:06:31 +08:00
Kelv 2477bcc32e
DEV: lint against Layout/EmptyLineBetweenDefs (#24914) 2023-12-15 23:46:04 +08:00
David Taylor 7070f81596
DEV: Allow `DROP NOT NULL` in pre-deploy migrations (#20775)
Our SafeMigrate system is designed to prevent tables/columns being dropped in pre-deploy migrations. Its regex-based detection was triggering incorrectly on `ALTER COLUMN DROP NOT NULL`.
2023-03-22 14:43:32 +00:00
Daniel Waterworth 666536cbd1
DEV: Prefer \A and \z over ^ and $ in regexes (#19936) 2023-01-20 12:52:49 -06:00
David Taylor 6417173082
DEV: Apply syntax_tree formatting to `lib/*` 2023-01-09 12:10:19 +00:00
Jarek Radosz 2fc70c5572
DEV: Correctly tag heredocs (#16061)
This allows text editors to use correct syntax coloring for the heredoc sections.

Heredoc tag names we use:

languages: SQL, JS, RUBY, LUA, HTML, CSS, SCSS, SH, HBS, XML, YAML/YML, MF, ICS
other: MD, TEXT/TXT, RAW, EMAIL
2022-02-28 20:50:55 +01:00
David Taylor e76c583b91
DEV: Promote old post-deploy migrations to pre-deploy migrations (#13477)
Having a large number of post-deploy migrations running out-of-numerical-sequence with pre-deploy migrations can be problematic. For example, if we have the sequence

- db/migrate/2017... - add column
- db/post_migrate/2018... - drop the column
- db/migrate/2021... - add the same column again

It will work fine in numerical order. But if you run the pre-deploy migrations **followed by** the post-deploy migrations, you will not get the same result.

Our post-deploy system is designed to allow for seamless upgrades of Discourse. However, it is reasonable for us to only support this totally seamless experience for a limited period of time. This commit moves all post_deploy migrations which are more than 1 year old (i.e. more than 2 major Discourse versions ago) into the regular pre-deploy migrations directory. This limits the impact of any edge cases caused by out-of-numerical-sequence migrations.
2021-06-22 16:02:24 +01:00
Guo Xiang Tan 9ab5801a1b
FIX: Allow post migrations using `#change` to carry out unsafe migration 2020-05-15 14:23:27 +08:00
Sam Saffron e2284cf739
Revert "We have had errors reported due to migrations breaking and are reverting"
This reverts commit 8b46f14744.

It corrects the reason for the revert:

We rely on SafeMigrate existing cause we call it from migrations,
Zeitwerk will autoload it.

Instead of previous pattern we explicitly bypass all the hacks in
production mode.

We need to disable SafeMigrate cause it is not thread safe.

A thread safe implementation is possible but not worth the effort,
we catch the issues in dev and test.
2020-04-14 11:31:07 +10:00
Gerhard Schlager e474cda321 REFACTOR: Restoring of backups and migration of uploads to S3 2020-01-14 11:41:35 +01:00
Sam Saffron 30990006a9 DEV: enable frozen string literal on all files
This reduces chances of errors where consumers of strings mutate inputs
and reduces memory usage of the app.

Test suite passes now, but there may be some stuff left, so we will run
a few sites on a branch prior to merging
2019-05-13 09:31:32 +08:00
David Taylor 9248ad1905 DEV: Enable `Style/SingleLineMethods` and `Style/Semicolon` in Rubocop (#6717) 2018-12-04 11:48:13 +08:00
Guo Xiang Tan 40fa96777d
FEATURE: Post deployment migrations. (#6406)
This moves us away from the delayed drops pattern which
was problematic on two counts. First, it uses a hardcoded "delay for"
duration which may be too short for certain deployment strategies.
Second, delayed drop doesn't ensure that it only runs after
the latest application code has been deployed. If the migration runs
and the application code fails to deploy, running the migration after
"delay for" has been met will cause the application to blow up.

The new strategy allows post deployment migrations to be skipped if the
env `SKIP_POST_DEPLOYMENT_MIGRATIONS` is provided.

```
SKIP_POST_DEPLOYMENT_MIGRATIONS=1 rake db:migrate
-> deploy app servers
SKIP_POST_DEPLOYMENT_MIGRATIONS=0 rake db:migrate
```

To aid with the generation of a post deployment migration, a generator
has been added. Simply run `rails generate post_migration`.
2018-10-08 15:47:38 +08:00
Gerhard Schlager 19c5afc69d Protect against accidental table renames 2018-03-27 13:18:13 +11:00
Sam 6a3c8fe69c FEATURE: protect against accidental column or table drops
Often we need to amend our schema, it is tempting to use
drop_table, rename_column and drop_column to amned schema
trouble though is that existing code that is running in production
can depend on the existance of previous schema leading to application
breaking until new code base is deployed.

The commit enforces new rules to ensure we can never drop tables or
columns in migrations and instead use Migration::ColumnDropper and
Migration::TableDropper to defer drop the db objects
2018-03-21 15:43:32 +11:00