1 files changed, 61 insertions, 0 deletions
diff --git a/tvix/store/src/pathinfoservice/mod.rs b/tvix/store/src/pathinfoservice/mod.rs
new file mode 100644
index 000000000000..af7bbc9f88e4
--- /dev/null
+++ b/tvix/store/src/pathinfoservice/mod.rs
@@ -0,0 +1,61 @@
+mod from_addr;
+mod grpc;
+mod memory;
+mod sled;
+
+use std::pin::Pin;
+use std::sync::Arc;
+
+use futures::Stream;
+use tonic::async_trait;
+use tvix_castore::blobservice::BlobService;
+use tvix_castore::directoryservice::DirectoryService;
+use tvix_castore::proto as castorepb;
+use tvix_castore::Error;
+
+use crate::proto::PathInfo;
+
+pub use self::from_addr::from_addr;
+pub use self::grpc::GRPCPathInfoService;
+pub use self::memory::MemoryPathInfoService;
+pub use self::sled::SledPathInfoService;
+
+/// The base trait all PathInfo services need to implement.
+#[async_trait]
+pub trait PathInfoService: Send + Sync {
+    /// Create a new instance by passing in a connection URL, as well
+    /// as instances of a [PathInfoService] and [DirectoryService] (as the
+    /// [PathInfoService] needs to talk to them).
+    /// TODO: check if we want to make this async, instead of lazily connecting
+    fn from_url(
+        url: &url::Url,
+        blob_service: Arc<dyn BlobService>,
+        directory_service: Arc<dyn DirectoryService>,
+    ) -> Result<Self, Error>
+    where
+        Self: Sized;
+
+    /// Retrieve a PathInfo message by the output digest.
+    async fn get(&self, digest: [u8; 20]) -> Result<Option<PathInfo>, Error>;
+
+    /// Store a PathInfo message. Implementations MUST call validate and reject
+    /// invalid messages.
+    async fn put(&self, path_info: PathInfo) -> Result<PathInfo, Error>;
+
+    /// Return the nar size and nar sha256 digest for a given root node.
+    /// This can be used to calculate NAR-based output paths,
+    /// and implementations are encouraged to cache it.
+    async fn calculate_nar(
+        &self,
+        root_node: &castorepb::node::Node,
+    ) -> Result<(u64, [u8; 32]), Error>;
+
+    /// Iterate over all PathInfo objects in the store.
+    /// Implementations can decide to disallow listing.
+    ///
+    /// This returns a pinned, boxed stream. The pinning allows for it to be polled easily,
+    /// and the box allows different underlying stream implementations to be returned since
+    /// Rust doesn't support this as a generic in traits yet. This is the same thing that
+    /// [async_trait] generates, but for streams instead of futures.
+    fn list(&self) -> Pin<Box<dyn Stream<Item = Result<PathInfo, Error>> + Send>>;
+}