From ab5f9c52cfeb3bfc9ad01b63f9b3557339313932 Mon Sep 17 00:00:00 2001
From: Luis Herasme <luis.alberto.herasme.cuevas@gmail.com>
Date: Thu, 25 Jul 2024 23:30:28 -0400
Subject: [PATCH] refactor: Refactor indexer and add errors

---
 ghost-crab-macros/src/lib.rs            |  2 +-
 ghost-crab/src/block_handler.rs         |  2 +-
 ghost-crab/src/event_handler.rs         |  2 +-
 ghost-crab/src/indexer/error.rs         | 22 +++++++
 ghost-crab/src/{ => indexer}/indexer.rs | 78 ++++++++++++-------------
 ghost-crab/src/indexer/mod.rs           |  3 +
 ghost-crab/src/indexer/templates.rs     | 26 +++++++++
 ghost-crab/src/lib.rs                   |  2 +-
 ghost-crab/src/prelude.rs               |  2 +-
 9 files changed, 94 insertions(+), 45 deletions(-)
 create mode 100644 ghost-crab/src/indexer/error.rs
 rename ghost-crab/src/{ => indexer}/indexer.rs (68%)
 create mode 100644 ghost-crab/src/indexer/mod.rs
 create mode 100644 ghost-crab/src/indexer/templates.rs

diff --git a/ghost-crab-macros/src/lib.rs b/ghost-crab-macros/src/lib.rs
index ace44d8..bbf2916 100644
--- a/ghost-crab-macros/src/lib.rs
+++ b/ghost-crab-macros/src/lib.rs
@@ -48,7 +48,7 @@ pub fn block_handler(metadata: TokenStream, input: TokenStream) -> TokenStream {
                 #fn_body
             }
 
-            fn name() -> String {
+            fn name(&self) -> String {
                 String::from(#name)
             }
         }
diff --git a/ghost-crab/src/block_handler.rs b/ghost-crab/src/block_handler.rs
index 3235d7f..4de9626 100644
--- a/ghost-crab/src/block_handler.rs
+++ b/ghost-crab/src/block_handler.rs
@@ -1,5 +1,5 @@
 use crate::cache::manager::CacheProvider;
-use crate::indexer::TemplateManager;
+use crate::indexer::templates::TemplateManager;
 use crate::latest_block_manager::LatestBlockManager;
 use alloy::providers::Provider;
 use alloy::rpc::types::eth::Block;
diff --git a/ghost-crab/src/event_handler.rs b/ghost-crab/src/event_handler.rs
index c4df51e..71d8429 100644
--- a/ghost-crab/src/event_handler.rs
+++ b/ghost-crab/src/event_handler.rs
@@ -1,5 +1,5 @@
 use crate::cache::manager::CacheProvider;
-use crate::indexer::TemplateManager;
+use crate::indexer::templates::TemplateManager;
 use crate::latest_block_manager::LatestBlockManager;
 use alloy::eips::BlockNumberOrTag;
 use alloy::primitives::Address;
diff --git a/ghost-crab/src/indexer/error.rs b/ghost-crab/src/indexer/error.rs
new file mode 100644
index 0000000..040686d
--- /dev/null
+++ b/ghost-crab/src/indexer/error.rs
@@ -0,0 +1,22 @@
+use core::fmt;
+
+#[derive(Debug)]
+pub enum AddHandlerError {
+    NotFound(String),
+    NetworkNotFound(String),
+}
+
+impl fmt::Display for AddHandlerError {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        match self {
+            AddHandlerError::NotFound(handler) => {
+                write!(f, "Handler not found: {}", handler)
+            }
+            AddHandlerError::NetworkNotFound(network) => {
+                write!(f, "Network not found: {}", network)
+            }
+        }
+    }
+}
+
+impl std::error::Error for AddHandlerError {}
diff --git a/ghost-crab/src/indexer.rs b/ghost-crab/src/indexer/indexer.rs
similarity index 68%
rename from ghost-crab/src/indexer.rs
rename to ghost-crab/src/indexer/indexer.rs
index 653d42f..b327ca6 100644
--- a/ghost-crab/src/indexer.rs
+++ b/ghost-crab/src/indexer/indexer.rs
@@ -1,27 +1,12 @@
 use crate::block_handler::{process_blocks, BlockHandlerInstance, ProcessBlocksInput};
 use crate::cache::manager::RPCManager;
 use crate::event_handler::{process_events, EventHandlerInstance, ProcessEventsInput};
-use alloy::primitives::Address;
+
 use ghost_crab_common::config::{self, Config, ConfigError};
-use tokio::sync::mpsc::error::SendError;
-use tokio::sync::mpsc::{self, Receiver, Sender};
+use tokio::sync::mpsc::{self, Receiver};
 
-pub struct Template {
-    pub start_block: u64,
-    pub address: Address,
-    pub handler: EventHandlerInstance,
-}
-
-#[derive(Clone)]
-pub struct TemplateManager {
-    tx: Sender<Template>,
-}
-
-impl TemplateManager {
-    pub async fn start(&self, template: Template) -> Result<(), SendError<Template>> {
-        self.tx.send(template).await
-    }
-}
+use super::error::AddHandlerError;
+use super::templates::{Template, TemplateManager};
 
 pub struct Indexer {
     handlers: Vec<ProcessEventsInput>,
@@ -42,7 +27,7 @@ impl Indexer {
             config,
             handlers: Vec::new(),
             block_handlers: Vec::new(),
-            templates: TemplateManager { tx },
+            templates: TemplateManager::new(tx),
             rpc_manager: RPCManager::new(),
             rx,
         })
@@ -68,26 +53,39 @@ impl Indexer {
         });
     }
 
-    pub async fn load_block_handler(&mut self, handler: BlockHandlerInstance) {
-        if let Some(block_config) = self.config.block_handlers.remove(&handler.name()) {
-            if let Some(network) = self.config.networks.get(&block_config.network) {
-                let provider = self
-                    .rpc_manager
-                    .get_or_create(
-                        block_config.network.clone(),
-                        network.rpc_url.clone(),
-                        network.requests_per_second,
-                    )
-                    .await;
-
-                self.block_handlers.push(ProcessBlocksInput {
-                    handler,
-                    templates: self.templates.clone(),
-                    provider,
-                    config: block_config,
-                });
-            }
-        }
+    pub async fn load_block_handler(
+        &mut self,
+        handler: BlockHandlerInstance,
+    ) -> Result<(), AddHandlerError> {
+        let block_config = self
+            .config
+            .block_handlers
+            .remove(&handler.name())
+            .ok_or(AddHandlerError::NotFound(handler.name()))?;
+
+        let network = self
+            .config
+            .networks
+            .get(&block_config.network)
+            .ok_or(AddHandlerError::NetworkNotFound(block_config.network.clone()))?;
+
+        let provider = self
+            .rpc_manager
+            .get_or_create(
+                block_config.network.clone(),
+                network.rpc_url.clone(),
+                network.requests_per_second,
+            )
+            .await;
+
+        self.block_handlers.push(ProcessBlocksInput {
+            handler,
+            templates: self.templates.clone(),
+            provider,
+            config: block_config,
+        });
+
+        Ok(())
     }
 
     pub async fn start(mut self) {
diff --git a/ghost-crab/src/indexer/mod.rs b/ghost-crab/src/indexer/mod.rs
new file mode 100644
index 0000000..28fca33
--- /dev/null
+++ b/ghost-crab/src/indexer/mod.rs
@@ -0,0 +1,3 @@
+pub mod error;
+pub mod indexer;
+pub mod templates;
diff --git a/ghost-crab/src/indexer/templates.rs b/ghost-crab/src/indexer/templates.rs
new file mode 100644
index 0000000..4595474
--- /dev/null
+++ b/ghost-crab/src/indexer/templates.rs
@@ -0,0 +1,26 @@
+use alloy::primitives::Address;
+use tokio::sync::mpsc::error::SendError;
+use tokio::sync::mpsc::Sender;
+
+use crate::event_handler::EventHandlerInstance;
+
+pub struct Template {
+    pub start_block: u64,
+    pub address: Address,
+    pub handler: EventHandlerInstance,
+}
+
+#[derive(Clone)]
+pub struct TemplateManager {
+    tx: Sender<Template>,
+}
+
+impl TemplateManager {
+    pub fn new(tx: Sender<Template>) -> TemplateManager {
+        TemplateManager { tx }
+    }
+
+    pub async fn start(&self, template: Template) -> Result<(), SendError<Template>> {
+        self.tx.send(template).await
+    }
+}
diff --git a/ghost-crab/src/lib.rs b/ghost-crab/src/lib.rs
index 66e79dd..b4b6837 100644
--- a/ghost-crab/src/lib.rs
+++ b/ghost-crab/src/lib.rs
@@ -5,7 +5,7 @@ pub mod indexer;
 pub mod prelude;
 
 pub use ghost_crab_common::config;
-pub use indexer::Indexer;
+pub use indexer::indexer::Indexer;
 
 mod latest_block_manager;
 mod rate_limit;
diff --git a/ghost-crab/src/prelude.rs b/ghost-crab/src/prelude.rs
index d1a2715..547dbcb 100644
--- a/ghost-crab/src/prelude.rs
+++ b/ghost-crab/src/prelude.rs
@@ -16,7 +16,7 @@ pub use crate::block_handler::{BlockContext, BlockHandler};
 pub use crate::cache;
 pub use crate::config;
 pub use crate::indexer;
-pub use crate::indexer::Template;
+pub use crate::indexer::templates::Template;
 pub use alloy::primitives::address;
 pub use alloy::primitives::Address;
 pub use alloy::providers::Provider;