Add README for Rust-based VSS implementation.

rust/README.md

@@ -1,2 +1,39 @@
-## WIP
-Not ready for use !!
+# Versioned Storage Service (Rust)
+
+This directory hosts the Rust-based implementation of the Versioned Storage Service (VSS).
+
+### Prerequisites
+
+- Install Rust and Cargo (https://www.rust-lang.org/tools/install).
+- Install PostgreSQL 15 (https://www.postgresql.org/download/)
+
+### Building
+
+```
+git clone https://github.com/lightningdevkit/vss-server.git
+cd vss-server/rust
+
+cargo build --release
+```
+
+### Running
+1. **Edit Configuration**: Modify `./vss_server_config.toml` to set application configuration and
+   environment variables as needed. Add PostgreSQL endpoint configuration.
+2. Create table in PostgreSQL using `./impls/src/postgres/sql/`
+3. Start server:
+    ```
+        cargo run -- vss-server-config.toml
+    ```
+3. VSS endpoint should be reachable at `http://localhost:8080/vss`.
+
+### Configuration
+
+Refer `./vss_server_config.toml` to see available configuration options.
+
+### Support
+
+If you encounter any issues or have questions, feel free to open an issue on
+the [GitHub repository](https://github.com/lightningdevkit/vss-server/issues). For further assistance or to discuss the
+development of VSS, you can reach out to us in the [LDK Discord](https://discord.gg/5AcknnMfBw) in the `#vss` channel.
+
+[LDK Discord]: https://discord.gg/5AcknnMfBw

rust/impls/src/postgres/sql/v0_create_vss_db.sql

@@ -0,0 +1,10 @@
+CREATE TABLE vss_db (
+    user_token character varying(120) NOT NULL CHECK (user_token <> ''),
+    store_id character varying(120) NOT NULL CHECK (store_id <> ''),
+    key character varying(600) NOT NULL,
+    value bytea NULL,
+    version bigint NOT NULL,
+    created_at TIMESTAMP WITH TIME ZONE,
+    last_updated_at TIMESTAMP WITH TIME ZONE,
+    PRIMARY KEY (user_token, store_id, key)
+);