very elegant extension API and parts of it used in std as POC

orchid-api/src/interner.rs

@@ -0,0 +1,89 @@
+use std::num::NonZeroU64;
+use std::sync::Arc;
+
+use orchid_api_derive::{Coding, Hierarchy};
+use orchid_api_traits::Request;
+
+use crate::proto::{ExtHostReq, HostExtReq};
+
+/// Intern requests sent by the replica to the master. These requests are
+/// repeatable.
+#[derive(Clone, Debug, Coding, Hierarchy)]
+#[extends(ExtHostReq)]
+#[extendable]
+pub enum IntReq {
+  InternStr(InternStr),
+  InternStrv(InternStrv),
+  ExternStr(ExternStr),
+  ExternStrv(ExternStrv),
+}
+
+/// replica -> master to intern a string on the master. Repeatable.
+///
+/// See [IntReq]
+#[derive(Clone, Debug, Hash, PartialEq, Eq, Coding, Hierarchy)]
+#[extends(IntReq, ExtHostReq)]
+pub struct InternStr(pub Arc<String>);
+impl Request for InternStr {
+  type Response = TStr;
+}
+
+/// replica -> master to find the interned string corresponding to a key.
+///
+/// Repeatable.
+///
+/// See [IntReq]
+#[derive(Clone, Debug, Coding, Hierarchy)]
+#[extends(IntReq, ExtHostReq)]
+pub struct ExternStr(pub TStr);
+impl Request for ExternStr {
+  type Response = Arc<String>;
+}
+/// replica -> master to intern a vector of interned strings
+///
+/// Repeatable.
+///
+/// See [IntReq]
+#[derive(Clone, Debug, Coding, Hierarchy)]
+#[extends(IntReq, ExtHostReq)]
+pub struct InternStrv(pub Arc<Vec<TStr>>);
+impl Request for InternStrv {
+  type Response = TStrv;
+}
+/// replica -> master to find the vector of interned strings corresponding to a
+/// token
+///
+/// Repeatable.
+///
+/// See [IntReq]
+#[derive(Clone, Debug, Coding, Hierarchy)]
+#[extends(IntReq, ExtHostReq)]
+pub struct ExternStrv(pub TStrv);
+impl Request for ExternStrv {
+  type Response = Arc<Vec<TStr>>;
+}
+
+/// A substitute for an interned string in serialized datastructures.
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
+pub struct TStr(pub NonZeroU64);
+
+/// A substitute for an interned string sequence in serialized datastructures.
+#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq, PartialOrd, Ord, Coding)]
+pub struct TStrv(pub NonZeroU64);
+
+/// A request to sweep the replica. The master will not be sweeped until all
+/// replicas respond, as it must retain everything the replicas retained
+#[derive(Clone, Copy, Debug, Coding, Hierarchy)]
+#[extends(HostExtReq)]
+pub struct Sweep;
+impl Request for Sweep {
+  type Response = Retained;
+}
+
+/// List of keys in this replica that couldn't be sweeped because local
+/// datastructures reference their value.
+#[derive(Clone, Debug, Coding)]
+pub struct Retained {
+  pub strings: Vec<TStr>,
+  pub vecs: Vec<TStrv>,
+}