feat: example app (#99)

examples/basic/src/main.rs

@@ -0,0 +1,116 @@
+use std::io::Error;
+use std::str::from_utf8;
+use std::time::SystemTime;
+use tokio::time::{sleep, Duration};
+use waku::{
+    waku_destroy, waku_new, Encoding, Event, WakuContentTopic, WakuMessage, WakuNodeConfig,
+};
+
+#[tokio::main]
+async fn main() -> Result<(), Error> {
+    let node1 = waku_new(Some(WakuNodeConfig {
+        port: Some(60010), // TODO: use any available port.
+        ..Default::default()
+    }))
+    .expect("should instantiate");
+
+    let node2 = waku_new(Some(WakuNodeConfig {
+        port: Some(60020), // TODO: use any available port.
+        ..Default::default()
+    }))
+    .expect("should instantiate");
+
+    let node1 = node1.start().expect("node1 should start");
+    let node2 = node2.start().expect("node2 should start");
+
+    // ========================================================================
+    // Setting an event callback to be executed each time a message is received
+    node2.set_event_callback(move |event| {
+        if let Event::WakuMessage(message) = event {
+            let message = message.waku_message;
+            let payload = message.payload.to_vec();
+            let msg = from_utf8(&payload).expect("should be valid message");
+            println!("::::::::::::::::::::::::::::::::::::::::::::::::::::");
+            println!("Message Received in NODE 2: {}", msg);
+            println!("::::::::::::::::::::::::::::::::::::::::::::::::::::");
+        }
+    });
+
+    node1.set_event_callback(move |event| {
+        if let Event::WakuMessage(message) = event {
+            let message = message.waku_message;
+            let payload = message.payload.to_vec();
+            let msg = from_utf8(&payload).expect("should be valid message");
+            println!("::::::::::::::::::::::::::::::::::::::::::::::::::::");
+            println!("Message Received in NODE 1: {}", msg);
+            println!("::::::::::::::::::::::::::::::::::::::::::::::::::::");
+        }
+    });
+
+    // ========================================================================
+    // Subscribe to pubsub topic
+    let topic = "test".to_string();
+
+    node1
+        .relay_subscribe(&topic)
+        .expect("node1 should subscribe");
+
+    node2
+        .relay_subscribe(&topic)
+        .expect("node2 should subscribe");
+
+    // ========================================================================
+    // Connect nodes with each other
+
+    let addresses2 = node2
+        .listen_addresses()
+        .expect("should obtain the addresses");
+
+    node1
+        .connect(&addresses2[0], None)
+        .expect("node1 should connect to node2");
+
+    // ========================================================================
+    // Wait for gossipsub mesh to form
+
+    sleep(Duration::from_secs(2)).await;
+
+    // ========================================================================
+    // Publish a message
+
+    let content_topic = WakuContentTopic::new("waku", "2", "test", Encoding::Proto);
+    let message = WakuMessage::new(
+        "Hello world",
+        content_topic,
+        0,
+        SystemTime::now()
+            .duration_since(SystemTime::UNIX_EPOCH)
+            .unwrap()
+            .as_millis()
+            .try_into()
+            .unwrap(),
+        Vec::new(),
+        false,
+    );
+    node1
+        .relay_publish_message(&message, &topic, None)
+        .expect("should have sent the message");
+
+    // ========================================================================
+    // Waiting for message to arrive
+
+    sleep(Duration::from_secs(1)).await;
+
+    // ========================================================================
+    // Stop both instances
+
+    let node1 = node1.stop().expect("should stop");
+    let node2 = node2.stop().expect("should stop");
+
+    // ========================================================================
+    // Free resources
+    waku_destroy(node1).expect("should deallocate");
+    waku_destroy(node2).expect("should deallocate");
+
+    Ok(())
+}