Merge pull request 'Reorganize dependencies' (#373) from improve-deps into main

This PR includes work from @jirutka :

- [x] Allow linking against system-provided libraries (libsodium, libsqlite, libzstd) #370
- [x] Make OTLP exporter optional and allow building without Prometheus exporter (/metrics) #372

And also:

- [x] Update `.nix` files
- [x] Remove heed default-features
- [x] Bump versions of all Garage crates to 0.8.0
- [x] Make db engines (lmdb, sled, sqlite) optionnal
- [x] Add documentation for available features
- [x] Directly include code of previous versions used for migration in order to reduce dependencies
- [x] Read variable `GIT_VERSION` from garage main instead of in crate garage_util to make builds faster
- [x] Report features used in the build somewhere? (in `garage --version` or something)
- [x] Check we `warn!` correctly if we try to use deactivated feature
- [x] Allow not to launch S3 endpoint if not in config

Reviewed-on: https://git.deuxfleurs.fr/Deuxfleurs/garage/pulls/373

1 files changed, 24 insertions, 3 deletions

diff --git a/src/util/version.rs b/src/util/version.rs
index 8882d035..b515dccc 100644
--- a/src/util/version.rs
+++ b/src/util/version.rs
@@ -1,7 +1,28 @@
-pub fn garage() -> &'static str {
-	option_env!("GIT_VERSION").unwrap_or(git_version::git_version!(
+use std::sync::Arc;
+
+use arc_swap::{ArcSwap, ArcSwapOption};
+
+lazy_static::lazy_static! {
+	static ref VERSION: ArcSwap<&'static str> = ArcSwap::new(Arc::new(git_version::git_version!(
 		prefix = "git:",
 		cargo_prefix = "cargo:",
 		fallback = "unknown"
-	))
+	)));
+	static ref FEATURES: ArcSwapOption<&'static [&'static str]> = ArcSwapOption::new(None);
+}
+
+pub fn garage_version() -> &'static str {
+	&VERSION.load()
+}
+
+pub fn garage_features() -> Option<&'static [&'static str]> {
+	FEATURES.load().as_ref().map(|f| &f[..])
+}
+
+pub fn init_version(version: &'static str) {
+	VERSION.store(Arc::new(version));
+}
+
+pub fn init_features(features: &'static [&'static str]) {
+	FEATURES.store(Some(Arc::new(features)));
 }