Add documentation

crates/rdsys-backend/src/lib.rs

@@ -1,3 +1,8 @@
+//! # Rdsys Backend Distributor API
+//!
+//! `rdsys_backend` is an implementation of the rdsys backend API
+//! https://gitlab.torproject.org/tpo/anti-censorship/rdsys/-/blob/main/doc/backend-api.md
+
 use bytes::{self, Buf, Bytes};
 use futures_util::StreamExt;
 use reqwest::Client;
@@ -32,6 +37,8 @@ impl From<io::Error> for Error {
     }
 }
 
+/// An iterable wrapper of ResourceDiff items for the streamed chunks of Bytes
+/// received from the connection to the rdsys backend
 pub struct ResourceStream {
     rx: mpsc::Receiver<Bytes>,
     buf: Vec<u8>,
@@ -160,6 +167,23 @@ mod tests {
     }
 }
 
+/// Makes an http connection to the rdsys backend api endpoint and returns a ResourceStream
+/// if successful
+///
+/// # Examples
+/// use rdsys_backend::start_stream;
+///
+/// ```
+/// let endpoint = String::from("http://127.0.0.1:7100/resource-stream");
+/// let name = String::from("https");
+/// let token = String::from("HttpsApiTokenPlaceholder");
+/// let types = vec![String::from("obfs2"), String::from("scramblesuit")];
+/// let rx = start_stream(endpoint, name, token, types).await.unwrap();
+/// for diff in rx {
+///     println!("Received diff: {:?}", diff);
+/// }
+/// ```
+///
 pub async fn start_stream(
     api_endpoint: String,
     name: String,