replace RpcError with anyhow::Error

Cargo.lock

@@ -800,7 +800,6 @@ name = "cuprate-rpc-interface"
 version = "0.0.0"
 dependencies = [
  "axum",
- "cuprate-database",
  "cuprate-epee-encoding",
  "cuprate-helper",
  "cuprate-json-rpc",

Cargo.toml

@@ -48,6 +48,7 @@ opt-level     = 1
 opt-level = 3
 
 [workspace.dependencies]
+anyhow                = { version = "1.0.87", default-features = false }
 async-trait           = { version = "0.1.74", default-features = false }
 bitflags              = { version = "2.4.2", default-features = false }
 borsh                 = { version = "1.2.1", default-features = false }

rpc/interface/Cargo.toml

@@ -17,8 +17,8 @@ cuprate-epee-encoding = { path = "../../net/epee-encoding", default-features = f
 cuprate-json-rpc      = { path = "../json-rpc", default-features = false }
 cuprate-rpc-types     = { path = "../types", features = ["serde", "epee"], default-features = false }
 cuprate-helper        = { path = "../../helper", features = ["asynch"], default-features = false }
-cuprate-database      = { path = "../../storage/database" }
 
+anyhow     = { workspace = true }
 axum       = { version = "0.7.5", features = ["json"], default-features = false }
 serde      = { workspace = true, optional = true }
 tower      = { workspace = true }

rpc/interface/README.md

@@ -45,15 +45,16 @@ The proper usage of this crate is to:
 This is your [`tower::Service`] that converts `Request`s into `Response`s,
 i.e. the "inner handler".
 
-Said concretely, `RpcHandler` is 3 `tower::Service`s where the request/response types are
-the 3 endpoint enums from [`cuprate_rpc_types`] and the error type is from this crate:
+Said concretely, `RpcHandler` is 3 `tower::Service`s where the
+request/response types are the 3 endpoint enums from [`cuprate_rpc_types`]:
 - [`JsonRpcRequest`](cuprate_rpc_types::json::JsonRpcRequest) & [`JsonRpcResponse`](cuprate_rpc_types::json::JsonRpcResponse)
 - [`BinRequest`](cuprate_rpc_types::bin::BinRequest) & [`BinResponse`](cuprate_rpc_types::bin::BinRequest)
 - [`OtherRequest`](cuprate_rpc_types::other::OtherRequest) & [`OtherResponse`](cuprate_rpc_types::other::OtherRequest)
-- [`RpcError`]
 
 `RpcHandler`'s [`Future`](std::future::Future) is generic, _although_,
-it must output `Result<$RESPONSE, RpcError>`.
+it must output `Result<$RESPONSE, anyhow::Error>`.
+
+The error type must always be [`anyhow::Error`].
 
 The `RpcHandler` must also hold some state that is required
 for RPC server operation.

rpc/interface/src/lib.rs

@@ -3,14 +3,12 @@
 
 mod route;
 mod router_builder;
-mod rpc_error;
 mod rpc_handler;
 #[cfg(feature = "dummy")]
 mod rpc_handler_dummy;
 mod rpc_service;
 
 pub use router_builder::RouterBuilder;
-pub use rpc_error::RpcError;
 pub use rpc_handler::RpcHandler;
 #[cfg(feature = "dummy")]
 pub use rpc_handler_dummy::RpcHandlerDummy;

rpc/interface/src/rpc_error.rs

@@ -1,53 +0,0 @@
-//! RPC errors.
-
-//---------------------------------------------------------------------------------------------------- Import
-use axum::http::StatusCode;
-
-use cuprate_database::RuntimeError;
-
-//---------------------------------------------------------------------------------------------------- RpcError
-/// Possible errors during RPC operation.
-///
-/// These are any errors that can happen _during_ a handler function.
-/// I.e. if this error surfaces, it happened _after_ the request was
-/// deserialized.
-///
-/// This is the `Error` type required to be used in an [`RpcHandler`](crate::RpcHandler).
-///
-/// TODO: This is empty as possible errors will be
-/// enumerated when the handler functions are created.
-#[derive(Debug, thiserror::Error)]
-pub enum RpcError {
-    /// A [`std::io::Error`] from the database.
-    #[error("database I/O error: {0}")]
-    DatabaseIo(#[from] std::io::Error),
-
-    /// A (non-I/O related) database error.
-    #[error("database error: {0}")]
-    DatabaseError(RuntimeError),
-}
-
-impl From<RpcError> for StatusCode {
-    fn from(_: RpcError) -> Self {
-        // TODO
-        Self::INTERNAL_SERVER_ERROR
-    }
-}
-
-impl From<RuntimeError> for RpcError {
-    fn from(error: RuntimeError) -> Self {
-        match error {
-            RuntimeError::Io(io) => Self::DatabaseIo(io),
-            RuntimeError::KeyExists
-            | RuntimeError::KeyNotFound
-            | RuntimeError::ResizeNeeded
-            | RuntimeError::TableNotFound => Self::DatabaseError(error),
-        }
-    }
-}
-
-//---------------------------------------------------------------------------------------------------- Tests
-#[cfg(test)]
-mod test {
-    // use super::*;
-}

rpc/interface/src/rpc_handler.rs

@@ -22,7 +22,7 @@ use crate::RpcService;
 /// In other words, an [`RpcHandler`] is a type that implements [`tower::Service`] 3 times,
 /// one for each request/response enum type found in [`cuprate_rpc_types`].
 ///
-/// The error type must always be [`RpcError`](crate::RpcError).
+/// The error type must always be [`anyhow::Error`].
 ///
 /// See this crate's `RpcHandlerDummy` for an implementation example of this trait.
 ///

rpc/interface/src/rpc_service.rs

@@ -5,8 +5,6 @@ use std::future::Future;
 
 use tower::Service;
 
-use crate::rpc_error::RpcError;
-
 //---------------------------------------------------------------------------------------------------- RpcService
 /// An RPC [`tower::Service`].
 ///
@@ -17,7 +15,7 @@ use crate::rpc_error::RpcError;
 /// The `Request` and `Response` are generic and
 /// are used in the [`tower::Service`] bounds.
 ///
-/// The error type is always [`RpcError`].
+/// The error type is always [`anyhow::Error`].
 ///
 /// There is a blanket implementation that implements this
 /// trait on types that implement `tower::Service` correctly.
@@ -31,8 +29,8 @@ pub trait RpcService<Request, Response>:
     + Service<
         Request,
         Response = Response,
-        Error = RpcError,
-        Future: Future<Output = Result<Response, RpcError>> + Send + 'static,
+        Error = anyhow::Error,
+        Future: Future<Output = Result<Response, anyhow::Error>> + Send + 'static,
     >
 {
 }
@@ -45,8 +43,8 @@ impl<Request, Response, T> RpcService<Request, Response> for T where
         + Service<
             Request,
             Response = Response,
-            Error = RpcError,
-            Future: Future<Output = Result<Response, RpcError>> + Send + 'static,
+            Error = anyhow::Error,
+            Future: Future<Output = Result<Response, anyhow::Error>> + Send + 'static,
         >
 {
 }