Add shim client example

Signed-off-by: Maksym Pavlenko <pavlenko.maksym@gmail.com>

crates/shim-protos/Cargo.toml

@@ -9,7 +9,9 @@ description = "TTRPC bindings for containerd shim interfaces"
 
 [dependencies]
 protobuf = "2.23.0"
-ttrpc = "0.5.1"
+# Needs `Client::connect` to be published on crates.io
+# PR: https://github.com/containerd/ttrpc-rust/pull/93
+ttrpc = { git = "https://github.com/containerd/ttrpc-rust.git", rev = "da67137a8b89d6b796cb7e826ba2f6db2eed8f9e" }
 
 [build-dependencies]
 ttrpc-codegen = "0.2"

crates/shim-protos/README.md

@@ -1,3 +1,30 @@
 # Shim protos
 
 TTRPC bindings for containerd's shim events and interfaces.
+
+## Look and feel
+
+Basic client code looks as follows:
+
+```rust
+let client = client::Client::connect(socket_path)?;
+let task_client = client::TaskClient::new(client);
+
+let context = client::ttrpc::context::with_timeout(0);
+
+let req = client::api::ConnectRequest {
+    id: pid,
+    ..Default::default()
+};
+
+let resp = task_client.connect(context, &req)?;
+```
+
+## Example
+
+Have a look on example [here](./examples/connect.rs).
+
+```bash
+$ cargo build --example connect
+$ sudo ./connect unix:///containerd-shim/shim_socket_path.sock
+```

crates/shim-protos/examples/connect.rs

@@ -0,0 +1,34 @@
+use std::env;
+
+use containerd_shim_protos as client;
+
+fn main() {
+    let args: Vec<String> = env::args().collect();
+
+    let socket_path = args
+        .get(1)
+        .ok_or_else(|| "First argument must be shim socket path")
+        .unwrap();
+
+    let pid = args
+        .get(2)
+        .and_then(|str| Some(str.to_owned()))
+        .unwrap_or(String::new());
+
+    let client = client::Client::connect(socket_path).expect("Failed to connect to shim");
+
+    let task_client = client::TaskClient::new(client);
+
+    let context = client::ttrpc::context::with_timeout(0);
+
+    let req = client::api::ConnectRequest {
+        id: pid,
+        ..Default::default()
+    };
+
+    let resp = task_client
+        .connect(context, &req)
+        .expect("Connect request failed");
+
+    println!("Resp: {:?}", resp);
+}

crates/shim-protos/src/lib.rs

@@ -8,3 +8,7 @@ pub use ttrpc;
 pub mod events;
 #[rustfmt::skip]
 pub mod shim;
+
+pub use shim::shim as api;
+pub use shim::shim_ttrpc::{Task, TaskClient};
+pub use ttrpc::Client;