refactor poi radio as an example

examples/Cargo.toml

@@ -0,0 +1,5 @@
+[workspace]
+
+members = [
+    "poi-crosschecker"
+]

examples/poi-crosschecker/Cargo.toml

@@ -0,0 +1,30 @@
+[package]
+name = "poi-crosschecker"
+version = "0.1.0"
+edition = "2021"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+graphcast = { path = "../.." }
+waku = { package = "waku-bindings", git = "https://github.com/waku-org/waku-rust-bindings" }
+prost = "0.11"
+once_cell = "1.15"
+chrono = "0.4"
+serde = "1.0.147"
+serde_json = "1.0.87"
+tokio = {version = "1.1.1", features = ["full"]}
+anyhow = "1.0.39"
+graphql_client = "0.9.0"
+serde_derive = "1.0.114"
+reqwest = {version = "0.11.0", features = ["json"]}
+ethers = "1.0.0"
+ethers-contract = "1.0.0"
+ethers-core = "1.0.0"
+ethers-derive-eip712 = "1.0.0"
+colored = "2.0.0"
+partial_application = "0.2.1"
+num-bigint = "0.4.3"
+num-traits = "0.2.15"
+lazy_static = "1.4.0"
+thiserror = "1.0.30"

examples/poi-crosschecker/src/main.rs

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+use colored::*;
+use ethers::types::Block;
+use ethers::{
+    providers::{Http, Middleware, Provider},
+    types::U64,
+};
+
+use graphcast::gossip_agent::waku_handling::generate_pubsub_topics;
+use graphcast::gossip_agent::GossipAgent;
+
+
+
+use graphcast::graphql::query_graph_node_poi;
+
+
+use std::env;
+use std::{thread::sleep, time::Duration};
+use waku::{WakuPubSubTopic};
+
+#[macro_use]
+extern crate partial_application;
+
+#[tokio::main]
+async fn main() {
+    // Common inputs - refactor to a set-up function?
+    let graph_node_endpoint = String::from("http://localhost:8030/graphql");
+    let private_key = env::var("PRIVATE_KEY").expect("No private key provided.");
+    let eth_node = env::var("ETH_NODE").expect("No ETH URL provided.");
+
+    // Send message every x blocks for which wait y blocks before attestations
+    let examination_frequency = 2;
+    let wait_block_duration = 1;
+
+    let provider: Provider<Http> = Provider::<Http>::try_from(eth_node.clone()).unwrap();
+    let radio_name: &str = "poi-crosschecker";
+
+    let gossip_agent = GossipAgent::new(private_key, eth_node, radio_name)
+        .await
+        .unwrap();
+
+    let indexer_allocations = &gossip_agent.indexer_allocations;
+
+    //Note: using None will let message flow through default-waku peer nodes and filtered by graphcast poi-crosschecker as content topic
+    let topics: Vec<Option<WakuPubSubTopic>> =
+        generate_pubsub_topics(radio_name, indexer_allocations);
+
+    // Can be hidden away but leave attestation fn factored out
+    gossip_agent.message_handler();
+
+    let mut curr_block = 0;
+    let mut compare_block = 0;
+
+    // Main loop for sending messages, can factor out
+    // and take radio specific query and parsing for radioPayload
+    loop {
+        let block_number = U64::as_u64(&provider.get_block_number().await.unwrap()) - 5;
+
+        if curr_block == block_number {
+            sleep(Duration::from_secs(6));
+            continue;
+        }
+
+        println!("{} {}", "🔗 Block number:".cyan(), block_number);
+        curr_block = block_number;
+
+        // Send POI message at a fixed frequency
+        if block_number % examination_frequency == 0 {
+            compare_block = block_number + wait_block_duration;
+
+            let block: Block<_> = provider.get_block(block_number).await.unwrap().unwrap();
+            let block_hash = format!("{:#x}", block.hash.unwrap());
+
+            //CONSTRUCTING MESSAGE
+            // Radio specific message content query function
+            let poi_query = partial!( query_graph_node_poi => graph_node_endpoint.clone(), _, block_hash.to_string(),block_number.try_into().unwrap());
+
+            // Might make more sense to loop through indexer_allocation st we don't need to parse ipfs hash
+            // for ipfs_hash in indexer_allocations { - but would need topic generation, can refactor this later
+            for topic in topics.clone() {
+                let topic_title = topic.clone().unwrap().topic_name;
+                let ipfs_hash: &str = topic_title.split('-').collect::<Vec<_>>()[3];
+
+                if let Ok(Some(content)) = poi_query(ipfs_hash.to_string()).await {
+                    {
+                        let res = &gossip_agent
+                            .gossip_message(topic, block_number, content)
+                            .await;
+
+                        match res {
+                            Ok(sent) => println!("res!!! {}", sent),
+                            Err(e) => println!("eeeer!!! {}", e),
+                        };
+                    }
+                }
+            }
+            if block_number == compare_block {
+                println!("{}", "Compare attestations here".red());
+            }
+        }
+    }
+}