Update docs

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

crates/client/src/lib.rs

@@ -1,5 +1,8 @@
+//! A GRPC client to query containerd's API.
+
 pub use tonic;
 
+/// Generated `containerd.types` types.
 pub mod types {
     tonic::include_proto!("containerd.types");
 
@@ -8,12 +11,14 @@ pub mod types {
     }
 }
 
+/// Generated `google.rpc` types, containerd services typically use some of these types.
 pub mod google {
     pub mod rpc {
         tonic::include_proto!("google.rpc");
     }
 }
 
+/// Generated `containerd.services.*` services.
 pub mod services {
     pub mod v1 {
         tonic::include_proto!("containerd.services.containers.v1");
@@ -34,12 +39,14 @@ pub mod services {
     }
 }
 
+/// Generated event types.
 pub mod events {
     tonic::include_proto!("containerd.events");
 }
 
 /// Connect creates a unix channel to containerd GRPC socket.
-/// This helper inteded to be used in conjuction with Tokio runtime.
+///
+/// This helper inteded to be used in conjuction with [Tokio](https://tokio.rs) runtime.
 #[cfg(feature = "connect")]
 pub async fn connect(
     path: impl AsRef<std::path::Path>,

crates/logging/src/lib.rs

@@ -1,3 +1,5 @@
+//! Helper library to implement custom shim loggers for containerd.
+
 use std::env;
 use std::fmt;
 use std::fs;

crates/shim-client/src/lib.rs

@@ -1,3 +1,28 @@
+//! `containerd-shim-client` contains TTRPC bindings and client/server code to interact with
+//! containerd's runtime v2 shims.
+//!
+//! This crate relies on [ttrpc-rust](https://github.com/containerd/ttrpc-rust) crate to generate
+//! protobuf definitions and re-exports the TTRPC client for convenience.
+//!
+//! Here is a quick example:
+//! ```rust
+//! use containerd_shim_client as client;
+//!
+//! use client::api;
+//! use client::ttrpc::context::Context;
+//!
+//! // Create TTRPC client
+//! let client = client::Client::connect("unix:///socket.sock")?;
+//!
+//! // Get task client
+//! let task_client = client::TaskClient::new(client);
+//! let context = Context::default();
+//!
+//! // Send request and receive response
+//! let request = api::ConnectRequest::default();
+//! let response = task_client.connect(Context::default(), &request);
+//! ```
+
 // Supress warning: redundant field names in struct initialization
 #![allow(clippy::redundant_field_names)]
 
@@ -9,11 +34,14 @@ pub mod events;
 #[rustfmt::skip]
 pub mod shim;
 
+/// Includes event names shims can publish to containerd.
 pub mod topics;
 
+/// TTRPC client reexport for easier access.
 pub use ttrpc::Client;
 
 pub use shim::shim as api;
 pub use shim::shim_ttrpc::{Task, TaskClient};
 
+/// Shim events.
 pub use shim::events_ttrpc::{Events, EventsClient};

crates/shim/src/lib.rs

@@ -1,3 +1,5 @@
+//! A library to implement custom runtime v2 shims for containerd.
+
 use std::collections::hash_map::DefaultHasher;
 use std::env;
 use std::error;
@@ -28,6 +30,7 @@ mod reap;
 
 pub use publisher::RemotePublisher;
 
+/// Generated request/response structures.
 pub mod api {
     pub use super::protos::shim::empty::Empty;
     pub use super::protos::shim::shim::*;
@@ -115,6 +118,7 @@ pub trait Shim: Task {
     }
 }
 
+/// Shim entry point that must be invoked from `main`.
 pub fn run<T>(id: &str)
 where
     T: Shim + Send + Sync + 'static,
@@ -255,6 +259,7 @@ pub const SOCKET_ROOT: &str = "/run/containerd";
 #[cfg(target_os = "macos")]
 pub const SOCKET_ROOT: &str = "/var/run/containerd";
 
+/// Make socket path from namespace and id.
 pub fn socket_address(socket_path: &str, namespace: &str, id: &str) -> String {
     let path = PathBuf::from(socket_path)
         .join(namespace)

crates/shim/src/publisher.rs

@@ -1,3 +1,5 @@
+//! Implements a client to publish events from the shim back to containerd.
+
 use std::os::unix::io::RawFd;
 use std::time::{SystemTime, UNIX_EPOCH};
 
@@ -110,6 +112,7 @@ impl Events for RemotePublisher {
     }
 }
 
+/// Errors returned from client if something went wrong.
 #[derive(Debug, Error)]
 pub enum Error {
     #[error("Publisher TTRPC error: {0}")]