bug: set config env separator to double underscore. (#763)

Closes #762
Issue #320

src/settings.rs

@@ -108,7 +108,12 @@ impl Settings {
         }
 
         // Merge the environment overrides
-        s.merge(Environment::with_prefix(PREFIX))?;
+        // While the prefix is currently case insensitive, it's traditional that
+        // environment vars be UPPERCASE, this ensures that will continue should
+        // Environment ever change their policy about case insensitivity.
+        // This will accept environment variables specified as
+        // `SYNC_FOO__BAR_VALUE="gorp"` as `foo.bar_value = "gorp"`
+        s.merge(Environment::with_prefix(&PREFIX.to_uppercase()).separator("__"))?;
 
         Ok(match s.try_into::<Self>() {
             Ok(s) => {

src/web/extractors.rs

@@ -1045,7 +1045,7 @@ impl FromRequest for ConfigRequest {
                 max_request_bytes: data.max_request_bytes,
                 max_total_bytes: data.max_total_bytes,
                 max_total_records: data.max_total_records,
-                debug_client: None,
+                debug_client: data.debug_client.clone(),
             },
         }))
     }