From 033c23ef11d868ec7590b90b6cb79522d2e60f07 Mon Sep 17 00:00:00 2001
From: Kim Minh Kaplan <git@mel.kaplan.fr>
Date: Sat, 10 Nov 2018 09:15:23 +0000
Subject: [PATCH] Document that Authenticator does the Base64 encoding and
 decoding.

---
 src/authenticator.rs | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/src/authenticator.rs b/src/authenticator.rs
index ecfe93d..1351b7a 100644
--- a/src/authenticator.rs
+++ b/src/authenticator.rs
@@ -1,5 +1,16 @@
 /// This will allow plugable authentication mechanisms.
+///
+/// This trait is used by `Client::authenticate` to [authenticate
+/// using SASL](https://tools.ietf.org/html/rfc3501#section-6.2.2).
 pub trait Authenticator {
+    /// Type of the response to the challenge. This will usually be a
+    /// `Vec<u8>` or `String`. It must not be Base64 encoded: the
+    /// library will do it.
     type Response: AsRef<[u8]>;
+    /// For each server challenge is passed to `process`. The library
+    /// has already decoded the Base64 string into bytes.
+    ///
+    /// The `process` function should return its response, not Base64
+    /// encoded: the library will do it.
     fn process(&self, &[u8]) -> Self::Response;
 }