feat(example): Add consensus_pub_sub_with_submit_key example

Signed-off-by: Skyler Ross <[email protected]>

Author: izik1

examples/consensus.rs renamed to examples/consensus_pub_sub.rs

@@ -0,0 +1,104 @@
+use std::time::Duration;
+
+use clap::Parser;
+use futures_util::StreamExt;
+use hedera::{
+    AccountId, Client, PrivateKey, TopicCreateTransaction, TopicMessageQuery, TopicMessageSubmitTransaction
+};
+
+#[derive(Parser, Debug)]
+struct Args {
+    #[clap(long, env)]
+    operator_account_id: AccountId,
+
+    #[clap(long, env)]
+    operator_key: PrivateKey,
+
+    #[clap(long, env, default_value = "testnet")]
+    hedera_network: String,
+}
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+    let _ = dotenvy::dotenv();
+
+    let args = Args::parse();
+
+    let client = Client::for_name(&args.hedera_network)?;
+
+    client.set_operator(args.operator_account_id, args.operator_key);
+
+    // generate a submit key to use with the topic.
+    let submit_key = PrivateKey::generate_ed25519();
+
+    let topic_id = TopicCreateTransaction::new()
+        .topic_memo("sdk::rust::consensus_pub_sub_with_submit_key")
+        .submit_key(submit_key.public_key())
+        .execute(&client)
+        .await?
+        .get_receipt(&client)
+        .await?
+        .topic_id
+        .unwrap();
+
+    println!("Created Topic `{topic_id}` with submit key `{submit_key}`");
+
+    println!("Waiting 10s for the mirror node to catch up");
+
+    tokio::time::sleep(Duration::from_secs(10)).await;
+
+    let _handle: tokio::task::JoinHandle<hedera::Result<()>> = tokio::spawn({
+        let client = client.clone();
+        async move {
+            println!("sending 5 messages");
+
+            for i in 0..5 {
+                let v: i64 = rand::random();
+                let message = format!("random message: {v}");
+
+                println!("publishing message {i}: `{message}`");
+
+                TopicMessageSubmitTransaction::new()
+                    .topic_id(topic_id)
+                    .message(message)
+                    .sign(submit_key.clone())
+                    .execute(&client)
+                    .await?
+                    .get_receipt(&client)
+                    .await?;
+
+                tokio::time::sleep(Duration::from_secs(2)).await
+            }
+
+            println!(
+                "Finished sending the messages, press ctrl+c to exit once they're all recieved"
+            );
+
+            Ok(())
+        }
+    });
+
+    let client = client.clone();
+    let mut stream = TopicMessageQuery::new()
+        .topic_id(topic_id)
+        .subscribe(&client);
+
+    while let Some(elem) = stream.next().await {
+        let elem = match elem {
+            Ok(it) => it,
+            Err(e) => {
+                eprintln!("Error while handling message stream: {e:?}");
+                break;
+            }
+        };
+
+        println!(
+            "(seq: `{}`, contents: `{}`) reached consensus at {}",
+            elem.sequence_number,
+            String::from_utf8_lossy(&elem.contents),
+            elem.consensus_timestamp
+        );
+    }
+
+    Ok(())
+}