Add empty postgres KvStore implementation.

Author: G8XSU

rust/impls/Cargo.toml

@@ -0,0 +1,8 @@
+[package]
+name = "impls"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+async-trait = "0.1.77"
+api = { path = "../api" }

rust/impls/src/lib.rs

@@ -0,0 +1,15 @@
+//! Hosts VSS protocol compliant [`KvStore`] implementations for various backends.
+//!
+//! VSS is an open-source project designed to offer a server-side cloud storage solution specifically
+//! tailored for noncustodial Lightning supporting mobile wallets. Its primary objective is to
+//! simplify the development process for Lightning wallets by providing a secure means to store
+//! and manage the essential state required for Lightning Network (LN) operations.
+//!
+//! [`KvStore`]: api::kv_store::KvStore
+
+#![deny(rustdoc::broken_intra_doc_links)]
+#![deny(rustdoc::private_intra_doc_links)]
+#![deny(missing_docs)]
+
+/// Contains [PostgreSQL](https://www.postgresql.org/) based backend implementation for VSS.
+pub mod postgres_store;

rust/impls/src/postgres_store.rs

@@ -0,0 +1,45 @@
+use api::error::VssError;
+use api::kv_store::KvStore;
+use api::types::{
+	DeleteObjectRequest, DeleteObjectResponse, GetObjectRequest, GetObjectResponse,
+	ListKeyVersionsRequest, ListKeyVersionsResponse, PutObjectRequest, PutObjectResponse,
+};
+use async_trait::async_trait;
+use std::io::Error;
+
+/// A [PostgreSQL](https://www.postgresql.org/) based backend implementation for VSS.
+pub struct PostgresBackendImpl {}
+
+impl PostgresBackendImpl {
+	/// Constructs a [`PostgresBackendImpl`] using `dsn` for PostgreSQL connection information.
+	pub async fn new(dsn: &str) -> Result<Self, Error> {
+		todo!("pending implementation.");
+	}
+}
+
+#[async_trait]
+impl KvStore for PostgresBackendImpl {
+	async fn get(
+		&self, user_token: String, request: GetObjectRequest,
+	) -> Result<GetObjectResponse, VssError> {
+		todo!("pending implementation.");
+	}
+
+	async fn put(
+		&self, user_token: String, request: PutObjectRequest,
+	) -> Result<PutObjectResponse, VssError> {
+		todo!("pending implementation.");
+	}
+
+	async fn delete(
+		&self, user_token: String, request: DeleteObjectRequest,
+	) -> Result<DeleteObjectResponse, VssError> {
+		todo!("pending implementation.");
+	}
+
+	async fn list_key_versions(
+		&self, user_token: String, request: ListKeyVersionsRequest,
+	) -> Result<ListKeyVersionsResponse, VssError> {
+		todo!("pending implementation.");
+	}
+}