docs: Mention {http.auth.user.id} placeholder in basicauth JSON docs (#3886)

1 files changed, 5 insertions, 0 deletions

diff --git a/modules/caddyhttp/caddyauth/caddyauth.go b/modules/caddyhttp/caddyauth/caddyauth.go
index a88bff6..3a0a2a0 100644
--- a/modules/caddyhttp/caddyauth/caddyauth.go
+++ b/modules/caddyhttp/caddyauth/caddyauth.go
@@ -30,6 +30,11 @@ func init() {
 // Authentication is a middleware which provides user authentication.
 // Rejects requests with HTTP 401 if the request is not authenticated.
 //
+// After a successful authentication, the placeholder
+// `{http.auth.user.id}` will be set to the username, and also
+// `{http.auth.user.*}` placeholders may be set for any authentication
+// modules that provide user metadata.
+//
 // Its API is still experimental and may be subject to change.
 type Authentication struct {
 	// A set of authentication providers. If none are specified,