refactor: Move RpcConnection to a separate, thinner crate (#1199)

The first step towards removing dependency on program crates in SDK,
clients and third-party program.

This change moves `RpcConnection` trait and `SolanaRpcConnection`
implementation away from `forester-utils` and makes sure it doesn't
contain any program crate as dependency.

Cargo.toml

@@ -13,6 +13,7 @@ members = [
     "programs/system",
     "programs/compressed-token",
     "programs/registry",
+    "client",
     "sdk",
     "test-utils",
     "utils",
@@ -23,7 +24,7 @@ members = [
     "forester-utils",
     "forester",
     "photon-api",
-    "sdk"]
+]
 
 [profile.release]
 overflow-checks = true
@@ -32,6 +33,8 @@ overflow-checks = true
 opt-level = 2
 
 [workspace.dependencies]
+# Solana
+solana-banks-client = "=1.18.22"
 solana-banks-interface = "=1.18.22"
 solana-program = "=1.18.22"
 solana-sdk = "=1.18.22"
@@ -41,19 +44,34 @@ solana-cli-output = "=1.18.22"
 solana-transaction-status = "=1.18.22"
 solana-account-decoder = "=1.18.22"
 solana-rpc = "=1.18.22"
+spl-token = "=4.0.0"
 
-photon-api = { path = "photon-api" }
-
+# Anchor
 anchor-lang = "=0.29.0"
 anchor-spl = "=0.29.0"
 
-spl-token = "=4.0.0"
+# Anchor compatibility
+borsh = "0.10.0"
 
+# Macro helpers
 proc-macro2 = "1.0"
 quote = "1.0"
 syn = { version = "2.0", features = ["visit-mut", "full"] }
 
+# Async ecosystem
 tokio = { version = "1.39.1", features = ["rt", "macros", "rt-multi-thread"] }
+async-trait = "0.1.82"
+bb8 = "0.8.5"
+
+# Logging
+log = "0.4"
+
+# Error handling
+thiserror = "1.0"
+
+# Light Protocol
+light-client = { path = "client", version = "0.8.0" }
+photon-api = { path = "photon-api" }
 
 [patch.crates-io]
 "solana-account-decoder" = { git = "https://github.com/lightprotocol/agave", branch = "v1.18.22-enforce-cpi-tracking" }

client/Cargo.toml

@@ -0,0 +1,26 @@
+[package]
+name = "light-client"
+version = "0.8.0"
+edition = "2021"
+license = "Apache-2.0"
+repository = "https://github.com/lightprotocol/light-protocol"
+description = "Client library for Light Protocol"
+
+[dependencies]
+# Solana
+solana-banks-client = { workspace = true }
+solana-client = { workspace = true }
+solana-program = { workspace = true }
+solana-sdk = { workspace = true }
+solana-transaction-status = { workspace = true }
+
+# Anchor compatibility
+borsh = { workspace = true }
+
+# Async ecosystem
+tokio = { workspace = true }
+async-trait = { workspace = true }
+bb8 = { workspace = true }
+
+log = { workspace = true }
+thiserror = { workspace = true }

client/src/indexer/mod.rs

@@ -0,0 +1 @@
+pub trait Indexer: Sync + Send + Debug + 'static {}

client/src/lib.rs

@@ -0,0 +1,3 @@
+pub mod rpc;
+pub mod rpc_pool;
+pub mod transaction_params;

forester-utils/src/rpc/errors.rs → client/src/rpc/errors.rs

@@ -1,6 +1,6 @@
-use anchor_lang::solana_program::instruction::InstructionError;
+use solana_banks_client::BanksClientError;
 use solana_client::client_error::ClientError;
-use solana_program_test::BanksClientError;
+use solana_program::instruction::InstructionError;
 use solana_sdk::transaction::TransactionError;
 use std::io;
 use thiserror::Error;
@@ -10,9 +10,6 @@ pub enum RpcError {
     #[error("BanksError: {0}")]
     BanksError(#[from] BanksClientError),
 
-    #[error("ProgramTestError: {0}")]
-    ProgramTestError(#[from] solana_program_test::ProgramTestError),
-
     #[error("TransactionError: {0}")]
     TransactionError(#[from] TransactionError),
 
@@ -24,8 +21,13 @@ pub enum RpcError {
 
     #[error("Error: `{0}`")]
     CustomError(String),
+
     #[error("Assert Rpc Error: {0}")]
     AssertRpcError(String),
+
+    /// The chosen warp slot is not in the future, so warp is not performed
+    #[error("Warp slot not in the future")]
+    InvalidWarpSlot,
 }
 
 pub fn assert_rpc_error<T>(

forester-utils/src/rpc/rpc_connection.rs → client/src/rpc/rpc_connection.rs

@@ -1,9 +1,9 @@
 use crate::rpc::errors::RpcError;
 use crate::transaction_params::TransactionParams;
-use anchor_lang::solana_program::clock::Slot;
-use anchor_lang::solana_program::instruction::Instruction;
-use anchor_lang::AnchorDeserialize;
 use async_trait::async_trait;
+use borsh::BorshDeserialize;
+use solana_program::clock::Slot;
+use solana_program::instruction::Instruction;
 use solana_sdk::account::{Account, AccountSharedData};
 use solana_sdk::commitment_config::CommitmentConfig;
 use solana_sdk::epoch_info::EpochInfo;
@@ -47,7 +47,7 @@ pub trait RpcConnection: Send + Sync + Debug + 'static {
         transaction_params: Option<TransactionParams>,
     ) -> Result<Option<(T, Signature, Slot)>, RpcError>
     where
-        T: AnchorDeserialize + Send + Debug;
+        T: BorshDeserialize + Send + Debug;
 
     async fn create_and_send_transaction<'a>(
         &'a mut self,
@@ -71,7 +71,7 @@ pub trait RpcConnection: Send + Sync + Debug + 'static {
     async fn airdrop_lamports(&mut self, to: &Pubkey, lamports: u64)
         -> Result<Signature, RpcError>;
 
-    async fn get_anchor_account<T: AnchorDeserialize>(
+    async fn get_anchor_account<T: BorshDeserialize>(
         &mut self,
         pubkey: &Pubkey,
     ) -> Result<Option<T>, RpcError> {

forester-utils/src/rpc/solana_rpc.rs → client/src/rpc/solana_rpc.rs

@@ -1,23 +1,22 @@
 use crate::rpc::errors::RpcError;
 use crate::rpc::rpc_connection::RpcConnection;
 use crate::transaction_params::TransactionParams;
-use anchor_lang::prelude::Pubkey;
-use anchor_lang::solana_program::clock::Slot;
-use anchor_lang::solana_program::hash::Hash;
-use anchor_lang::AnchorDeserialize;
 use async_trait::async_trait;
+use borsh::BorshDeserialize;
 use log::warn;
 use solana_client::rpc_client::RpcClient;
 use solana_client::rpc_config::{RpcSendTransactionConfig, RpcTransactionConfig};
-use solana_program_test::BanksClientError;
+use solana_program::clock::Slot;
+use solana_program::hash::Hash;
+use solana_program::pubkey::Pubkey;
 use solana_sdk::account::{Account, AccountSharedData};
 use solana_sdk::bs58;
 use solana_sdk::clock::UnixTimestamp;
 use solana_sdk::commitment_config::CommitmentConfig;
 use solana_sdk::epoch_info::EpochInfo;
-use solana_sdk::instruction::{Instruction, InstructionError};
+use solana_sdk::instruction::Instruction;
 use solana_sdk::signature::{Keypair, Signature};
-use solana_sdk::transaction::{Transaction, TransactionError};
+use solana_sdk::transaction::Transaction;
 use solana_transaction_status::option_serializer::OptionSerializer;
 use solana_transaction_status::{UiInstruction, UiTransactionEncoding};
 use std::fmt::{Debug, Display, Formatter};
@@ -125,7 +124,7 @@ impl SolanaRpcConnection {
 }
 
 impl SolanaRpcConnection {
-    fn parse_inner_instructions<T: AnchorDeserialize>(
+    fn parse_inner_instructions<T: BorshDeserialize>(
         &self,
         signature: Signature,
     ) -> Result<T, RpcError> {
@@ -271,7 +270,7 @@ impl RpcConnection for SolanaRpcConnection {
         transaction_params: Option<TransactionParams>,
     ) -> Result<Option<(T, Signature, u64)>, RpcError>
     where
-        T: AnchorDeserialize + Send + Debug,
+        T: BorshDeserialize + Send + Debug,
     {
         let pre_balance = self.client.get_balance(payer)?;
         let latest_blockhash = self.client.get_latest_blockhash()?;
@@ -327,18 +326,7 @@ impl RpcConnection for SolanaRpcConnection {
                 - 5000 * deduped_signers.len() as i64
                 - network_fee;
             if post_balance as i64 != expected_post_balance {
-                println!("transaction_params: {:?}", transaction_params);
-                println!("pre_balance: {}", pre_balance);
-                println!("post_balance: {}", post_balance);
-                println!("expected post_balance: {}", expected_post_balance);
-                println!(
-                    "diff post_balance: {}",
-                    post_balance as i64 - expected_post_balance
-                );
-                println!("network_fee: {}", network_fee);
-                return Err(RpcError::from(BanksClientError::TransactionError(
-                    TransactionError::InstructionError(0, InstructionError::Custom(11111)),
-                )));
+                return Err(RpcError::AssertRpcError(format!("unexpected balance after transaction: expected {expected_post_balance}, got {post_balance}")));
             }
         }
 

forester/src/rpc_pool.rs → client/src/rpc_pool.rs

@@ -1,11 +1,11 @@
-use crate::RpcConnection;
 use bb8::{Pool, PooledConnection};
-use forester_utils::rpc::RpcError;
 use solana_sdk::commitment_config::CommitmentConfig;
 use std::time::Duration;
 use thiserror::Error;
 use tokio::time::sleep;
 
+use crate::rpc::{RpcConnection, RpcError};
+
 #[derive(Error, Debug)]
 pub enum PoolError {
     #[error("Failed to create RPC client: {0}")]

forester-utils/Cargo.toml

@@ -7,6 +7,7 @@ repository = "https://github.com/lightprotocol/light-protocol"
 description = "Utility library for Light's Forester node implementation"
 
 [dependencies]
+# Light Protocol
 account-compression = { path = "../programs/account-compression", version = "1.0.0", features = ["cpi"] }
 light-compressed-token = { path = "../programs/compressed-token", version = "1.0.0", features = ["cpi"] }
 light-hash-set = { path = "../merkle-tree/hash-set", version = "1.0.0" }
@@ -20,21 +21,33 @@ light-system-program = { path = "../programs/system", version = "1.0.0", feature
 light-utils = { path = "../utils", version = "1.0.0" }
 
 photon-api = { workspace = true }
+light-client = { workspace = true }
 
+# Anchor
 anchor-lang = { workspace = true }
 anchor-spl = { workspace = true }
 
+# Solana
 spl-token = { workspace = true, features = ["no-entrypoint"] }
 solana-program-test = { workspace = true }
 solana-sdk = { workspace = true }
 solana-client = { workspace = true }
 solana-transaction-status = { workspace = true }
 
+# Async ecosystem
 tokio = { workspace = true }
+async-trait = { workspace = true }
 
+# Error handling
 thiserror = "1.0"
+
+# Logging
 log = "0.4"
+
+# Big numbers
 num-bigint = "0.4.6"
 num-traits = "0.2.19"
+
+# HTTP client
 reqwest = "0.11.26"
-async-trait = "0.1.82"
+

forester-utils/src/address_merkle_tree_config.rs

@@ -1,4 +1,3 @@
-use crate::rpc::RpcConnection;
 use crate::{
     get_concurrent_merkle_tree, get_hash_set, get_indexed_merkle_tree,
     indexer::{AddressMerkleTreeAccounts, StateMerkleTreeAccounts},
@@ -8,6 +7,7 @@ use account_compression::{
     AddressMerkleTreeAccount, AddressMerkleTreeConfig, AddressQueueConfig, NullifierQueueConfig,
     QueueAccount, StateMerkleTreeAccount, StateMerkleTreeConfig,
 };
+use light_client::rpc::RpcConnection;
 use light_hasher::Poseidon;
 use num_traits::Zero;
 use solana_sdk::pubkey::Pubkey;

forester-utils/src/forester_epoch.rs

@@ -1,9 +1,9 @@
 use std::fmt::Display;
 // TODO: move into separate forester utils crate
-use crate::rpc::{RpcConnection, RpcError};
 use anchor_lang::{
     prelude::borsh, solana_program::pubkey::Pubkey, AnchorDeserialize, AnchorSerialize,
 };
+use light_client::rpc::{RpcConnection, RpcError};
 use light_registry::{
     protocol_config::state::{EpochState, ProtocolConfig},
     sdk::{create_register_forester_epoch_pda_instruction, create_report_work_instruction},

forester-utils/src/indexer/mod.rs

@@ -2,10 +2,10 @@ use num_bigint::BigUint;
 use solana_sdk::signature::Keypair;
 use std::fmt::Debug;
 
-use crate::rpc::RpcConnection;
 use account_compression::initialize_address_merkle_tree::{
     Error as AccountCompressionError, Pubkey,
 };
+use light_client::rpc::RpcConnection;
 use light_compressed_token::TokenData;
 use light_hash_set::HashSetError;
 use light_hasher::Poseidon;