feat: update redb to v2 (#2120)

## Description

`redb` 2.0.0 was released:
https://github.com/cberner/redb/releases/tag/v2.0.0

most relevant for us: 
> 2.0.0 uses a new file format that optimizes len() to be constant time.
This means that it is not backwards compatible with 1.x. To upgrade,
consider using a pattern like that shown in the
[upgrade_v1_to_v2](https://github.com/cberner/redb/blob/222a37f4600588261b0983eebcd074bb69d6e5a0/tests/backward_compatibility.rs#L282-L299)
test.

and some nice API changes that will simplify the iroh-sync codebase (no
more ouroboros for self-refential structs needed!)

> * Remove lifetimes from read-only tables
> * Remove lifetime from WriteTransaction and ReadTransaction

and some further API changes, see the notes.

---

* [x] Update iroh-bytes to redb v2
* Did some crude search&replaces to remove now unneeded lifetime bounds.
Compiles now, let's see what test says.
* [x] Migration for iroh-bytes db
* Code adapted from here
https://github.com/n0-computer/migrate-bao-store-redb/blob/main/src/main.rs
* [x] Update  iroh-sync to redb v2
* This will be a bit more involved as iroh-bytes because we hit more API
changes, but also great because we can remove `ouroborous` because
iterators can now own a range
* [x] Migration for iroh-sync db

The migrations likely need a dependency to redb v1 to read the old
database, so at least for one release cycle we'll have to depend on both
redb v2 and v1.

## Notes & open questions

This currently includes an extra-safeguard by preserving the old
databases for sync and blobs as `docs.redb.backup-redb-v1` and
`blobs.db-backup-redb-v1` - do we want this or delete the backups after
successfull migration?


## Change checklist

- [x] Self-review.
- [ ] Documentation updates if relevant.
- [ ] Tests if relevant.

---------

Co-authored-by: Friedel Ziegelmayer <me@dignifiedquire.com>

iroh-base/Cargo.toml

@@ -21,7 +21,7 @@ data-encoding = { version = "2.3.3", optional = true }
 hex = "0.4.3"
 multibase = { version = "0.9.1", optional = true }
 postcard = { version = "1", default-features = false, features = ["alloc", "use-std", "experimental-derive"], optional = true }
-redb = { version = "1.5.1", optional = true }
+redb = { version = "2.0.0", optional = true }
 serde = { version = "1", features = ["derive"] }
 serde-error = "0.1.2"
 thiserror = "1"

iroh-base/src/hash.rs

@@ -217,7 +217,7 @@ pub struct HashAndFormat {
 mod redb_support {
     use super::{Hash, HashAndFormat};
     use postcard::experimental::max_size::MaxSize;
-    use redb::{RedbKey, RedbValue};
+    use redb::{Key as RedbKey, Value as RedbValue};
 
     impl RedbValue for Hash {
         type SelfType<'a> = Self;
@@ -421,7 +421,7 @@ mod tests {
     #[cfg(feature = "redb")]
     #[test]
     fn hash_redb() {
-        use redb::RedbValue;
+        use redb::Value as RedbValue;
         let bytes: [u8; 32] = (0..32).collect::<Vec<_>>().as_slice().try_into().unwrap();
         let hash = Hash::from(bytes);
         assert_eq!(<Hash as RedbValue>::fixed_width(), Some(32));
@@ -446,7 +446,7 @@ mod tests {
     #[cfg(feature = "redb")]
     #[test]
     fn hash_and_format_redb() {
-        use redb::RedbValue;
+        use redb::Value as RedbValue;
         let hash_bytes: [u8; 32] = (0..32).collect::<Vec<_>>().as_slice().try_into().unwrap();
         let hash = Hash::from(hash_bytes);
         let haf = HashAndFormat::raw(hash);

iroh-bytes/Cargo.toml

@@ -38,12 +38,14 @@ postcard = { version = "1", default-features = false, features = ["alloc", "use-
 quinn = "0.10"
 rand = "0.8"
 range-collections = "0.4.0"
-redb = { version = "1.5.1", optional = true }
+redb = { version = "2.0.0", optional = true }
+redb_v1  = { package = "redb", version = "1.5.1", optional = true }
 reflink-copy = { version = "0.1.8", optional = true }
 self_cell = "1.0.1"
 serde = { version = "1", features = ["derive"] }
 serde-error = "0.1.2"
 smallvec = { version = "1.10.0", features = ["serde", "const_new"] }
+tempfile = { version = "3.10.0", optional = true }
 thiserror = "1"
 tokio = { version = "1", features = ["fs"] }
 tokio-util = { version = "0.7", features = ["io-util", "io", "rt"] }
@@ -64,7 +66,7 @@ tempfile = "3.10.0"
 
 [features]
 default = ["fs-store"]
-fs-store = ["reflink-copy", "redb"]
+fs-store = ["reflink-copy", "redb", "redb_v1", "tempfile"]
 downloader = ["iroh-net", "parking_lot", "tokio-util/time"]
 metrics = ["iroh-metrics"]
 

iroh-bytes/src/store/fs.rs

@@ -82,13 +82,14 @@ use futures::{channel::oneshot, Stream, StreamExt};
 
 use iroh_base::hash::{BlobFormat, Hash, HashAndFormat};
 use iroh_io::AsyncSliceReader;
-use redb::{AccessGuard, ReadableTable, StorageError};
+use redb::{AccessGuard, DatabaseError, ReadableTable, StorageError};
 use serde::{Deserialize, Serialize};
 use smallvec::SmallVec;
 use tokio::io::AsyncWriteExt;
 use tracing::trace_span;
 
 mod import_flat_store;
+mod migrate_redb_v1_v2;
 mod tables;
 #[doc(hidden)]
 pub mod test_support;
@@ -307,7 +308,7 @@ impl EntryState {
     }
 }
 
-impl redb::RedbValue for EntryState {
+impl redb::Value for EntryState {
     type SelfType<'a> = EntryState;
 
     type AsBytes<'a> = SmallVec<[u8; 128]>;
@@ -1218,6 +1219,8 @@ pub(crate) enum ActorError {
     Io(#[from] io::Error),
     #[error("inconsistent database state: {0}")]
     Inconsistent(String),
+    #[error("error during database migration: {0}")]
+    Migration(#[source] anyhow::Error),
 }
 
 impl From<ActorError> for io::Error {
@@ -1435,7 +1438,14 @@ impl Actor {
         temp: Arc<RwLock<TempCounterMap>>,
         rt: tokio::runtime::Handle,
     ) -> ActorResult<(Self, flume::Sender<ActorMessage>)> {
-        let db = redb::Database::create(path)?;
+        let db = match redb::Database::create(path) {
+            Ok(db) => db,
+            Err(DatabaseError::UpgradeRequired(1)) => {
+                migrate_redb_v1_v2::run(path).map_err(ActorError::Migration)?
+            }
+            Err(err) => return Err(err.into()),
+        };
+
         let txn = db.begin_write()?;
         // create tables and drop them just to create them.
         let mut t = Default::default();