| 1 | //! Rebuild `df-db` whenever a migration changes. | |
| 2 | //! | |
| 3 | //! `sqlx::migrate!` embeds the contents of `migrations/` into the binary at | |
| 4 | //! **compile time**. Cargo cannot see that dependency by itself: nothing in | |
| 5 | //! `src/` mentions those files, so adding a migration does not make the crate | |
| 6 | //! look dirty and the old set stays embedded. | |
| 7 | //! | |
| 8 | //! That failure is silent and nasty. The binary starts, reports "migrations up | |
| 9 | //! to date", and then every query against a column the missing migration was | |
| 10 | //! supposed to add fails at runtime — which is exactly how it presented when it | |
| 11 | //! happened here: a `column r.search does not exist` from a build that thought | |
| 12 | //! it had applied migration 3. | |
| 13 | //! | |
| 14 | //! Emitting the directory as a dependency makes the whole thing ordinary again. | |
| 15 | ||
| 16 | fn main() { | |
| 17 | // The directory itself, so an added or removed file is noticed… | |
| 18 | println!("cargo:rerun-if-changed=../../migrations"); | |
| 19 | ||
| 20 | // …and each file, so an *edited* one is too. A directory's mtime does not | |
| 21 | // change when a file inside it is modified in place. | |
| 22 | if let Ok(entries) = std::fs::read_dir("../../migrations") { | |
| 23 | for entry in entries.flatten() { | |
| 24 | println!("cargo:rerun-if-changed={}", entry.path().display()); | |
| 25 | } | |
| 26 | } | |
| 27 | } |
27 lines · Rust