feat(core): add VersionBytes MVReg decoding/encoding util fn

crdt-enc/src/utils.rs

@@ -2,9 +2,11 @@ mod version_bytes;
 
 pub use version_bytes::*;
 
-use ::crdts::{CmRDT, CvRDT};
+use ::anyhow::{Context, Result};
-use ::serde::{Deserialize, Serialize};
+use ::crdts::{ctx::ReadCtx, CmRDT, CvRDT, MVReg};
+use ::serde::{de::DeserializeOwned, Deserialize, Serialize};
 use ::std::convert::Infallible;
+use ::uuid::Uuid;
 
 #[derive(Debug, Clone, Default, Serialize, Deserialize)]
 pub struct EmptyCrdt;
@@ -30,3 +32,40 @@ impl CvRDT for EmptyCrdt {
 
     fn merge(&mut self, _other: Self) {}
 }
+
+pub fn decode_version_bytes_mvreg<T: DeserializeOwned + CvRDT + Default>(
+    reg: &MVReg<VersionBytes, Uuid>,
+    supported_versions: &[Uuid],
+) -> Result<ReadCtx<T, Uuid>> {
+    let (vals, read_ctx) = reg.read().split();
+    let val = vals
+        .into_iter()
+        .try_fold(T::default(), |mut acc, vb| -> Result<T> {
+            vb.ensure_versions(supported_versions)?;
+            let keys = rmp_serde::from_read_ref(&vb).context("Could not parse msgpack value")?;
+            acc.merge(keys);
+            Ok(acc)
+        })
+        .context("Could not process mvreg value")?;
+    Ok(ReadCtx {
+        add_clock: read_ctx.add_clock,
+        rm_clock: read_ctx.rm_clock,
+        val,
+    })
+}
+
+pub fn encode_version_bytes_mvreg<T: Serialize>(
+    reg: &mut MVReg<VersionBytes, Uuid>,
+    val: ReadCtx<T, Uuid>,
+    actor: Uuid,
+    version: Uuid,
+) -> Result<()> {
+    let (val, read_ctx) = val.split();
+    let vb = VersionBytes::new(
+        version,
+        rmp_serde::to_vec_named(&val).context("Could not serialize value to msgpack")?,
+    );
+    let op = reg.write(vb, read_ctx.derive_add_ctx(actor));
+    reg.apply(op);
+    Ok(())
+}