joining rooms, receiving messages

.gitignore

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+/target

Cargo.toml

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+[package]
+name = "matrixbot"
+version = "0.1.0"
+edition = "2021"
+
+[dependencies]
+anyhow = "1"
+matrix-sdk = "0.6"
+tokio = { version = "1", features = ["full"] }
+tracing-subscriber = "0.3"

src/main.rs

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+use matrix_sdk::{
+    config::SyncSettings,
+    room::Room,
+    ruma::{
+        events::room::member::StrippedRoomMemberEvent, events::room::message::SyncRoomMessageEvent,
+        user_id::OwnedUserId,
+    },
+    Client,
+};
+use tokio::time::{sleep, Duration};
+
+#[tokio::main]
+async fn main() -> anyhow::Result<()> {
+    tracing_subscriber::fmt::init();
+
+    let userid: OwnedUserId = std::env::args()
+        .nth(1)
+        .ok_or("need userid")
+        .map_err(anyhow::Error::msg)?
+        .try_into()?;
+    let client = Client::builder()
+        .server_name(userid.server_name())
+        .build()
+        .await?;
+
+    // First we need to log in.
+    client
+        .login_username(
+            &userid,
+            &std::env::args()
+                .nth(2)
+                .ok_or("need password")
+                .map_err(anyhow::Error::msg)?,
+        )
+        .send()
+        .await?;
+
+    client.add_event_handler(|ev: SyncRoomMessageEvent| async move {
+        println!("Received a message {:?}", ev);
+    });
+    client.add_event_handler(
+        |ev: StrippedRoomMemberEvent, client: Client, room: Room| async move {
+            if ev.state_key != client.user_id().unwrap() {
+                return;
+            }
+            if let Room::Invited(room) = room {
+                tokio::spawn(async move {
+                    println!("Autojoining {}", room.room_id());
+                    while let Err(err) = room.accept_invitation().await {
+                        eprintln!("Failed to join room {}: {:?}", room.room_id(), err);
+                        sleep(Duration::from_secs(5)).await;
+                    }
+                });
+            }
+        },
+    );
+
+    // Syncing is important to synchronize the client state with the server.
+    // This method will never return.
+    client.sync(SyncSettings::default()).await?;
+
+    Ok(())
+}