feat: Record the encoding in a metric if there is an encrypted payload (

#166)

This improves parity with Python autoendpoint.

autoendpoint/src/metrics.rs

@@ -80,10 +80,10 @@ impl From<&HttpRequest> for Metrics {
     }
 }
 
-impl From<&StatsdClient> for Metrics {
-    fn from(client: &StatsdClient) -> Self {
+impl From<StatsdClient> for Metrics {
+    fn from(client: StatsdClient) -> Self {
         Metrics {
-            client: Some(client.clone()),
+            client: Some(client),
             tags: None,
             timer: None,
         }

autoendpoint/src/server/extractors/notification.rs

@@ -6,6 +6,7 @@ use actix_web::dev::{Payload, PayloadStream};
 use actix_web::web::Data;
 use actix_web::{FromRequest, HttpRequest};
 use autopush_common::util::sec_since_epoch;
+use cadence::Counted;
 use futures::{future, FutureExt, StreamExt};
 
 /// Extracts notification data from `Subscription` and request data
@@ -52,6 +53,16 @@ impl FromRequest for Notification {
 
             let headers = NotificationHeaders::from_request(&req, data.is_some())?;
 
+            // Record the encoding if we have an encrypted payload
+            if let Some(encoding) = &headers.content_encoding {
+                if data.is_some() {
+                    state
+                        .metrics
+                        .incr(&format!("updates.notification.encoding.{}", encoding))
+                        .ok();
+                }
+            }
+
             Ok(Notification {
                 subscription,
                 headers,