update comments, flag subscribe_logs as non-runnable example

examples/subscriptions/examples/watch_contract_event.rs → examples/subscriptions/examples/poll_logs.rs

@@ -1,4 +1,4 @@
-//! Example of subscribing to blocks and watching contract events by WebSocket subscription.
+//! Example of watching and polling for contract events by WebSocket subscription.
 
 use alloy::{node_bindings::Anvil, providers::ProviderBuilder, rpc::client::WsConnect, sol};
 use eyre::Result;
@@ -58,7 +58,7 @@ async fn main() -> Result<()> {
         let _ = decrement_call.send().await?;
     }
 
-    // Listen for the events.
+    // Poll for logs.
     increment_filter
         .into_stream()
         .take(2)

examples/subscriptions/examples/subscribe_to_log_external_provider.rs → examples/subscriptions/examples/subscribe_logs.rs

@@ -1,4 +1,4 @@
-//! Example of subscribing to logs from the Ethereum network using an external provider.
+//! Example of subscribing and listening for contract events by WebSocket subscription.
 
 use alloy::{
     primitives::{address, b256},
@@ -13,6 +13,14 @@ use futures_util::stream::StreamExt;
 
 #[tokio::main]
 async fn main() -> Result<()> {
+    // Set up the WS transport which is consumed by the RPC client.
+    let rpc_url = "wss://eth-mainnet.g.alchemy.com/v2/your-api-key";
+
+    // Create the provider.
+    let ws = WsConnect::new(rpc_url);
+    let provider = ProviderBuilder::new().on_ws(ws).await?;
+
+    // Create a filter to watch for Uniswap token transfers.
     let uniswap_token_address = address!("1f9840a85d5aF5bf1D1762F925BDADdC4201F984");
     let tranfer_event_signature =
         b256!("ddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef");
@@ -21,13 +29,8 @@ async fn main() -> Result<()> {
         .event_signature(tranfer_event_signature)
         .from_block(BlockNumberOrTag::Latest);
 
-    let rpc_url = "wss://eth.merkle.io"; // DON'T use wss://eth.merkle.io _> this filters wrongly, tested alchemy.io's to be working fine
-
-    // Create the provider.
-    let ws = WsConnect::new(rpc_url);
-    let provider = ProviderBuilder::new().on_ws(ws).await.unwrap();
-
-    let sub = provider.subscribe_logs(&filter).await.expect("Failed to subscribe to logs");
+    // Subscribe to logs.
+    let sub = provider.subscribe_logs(&filter).await?;
     let mut stream = sub.into_stream();
 
     while let Some(log) = stream.next().await {