Expose factory traits and some clippy fixes (#983)

src/middleware/compress.rs

@@ -107,6 +107,7 @@ where
         self.service.poll_ready()
     }
 
+    #[allow(clippy::borrow_interior_mutable_const)]
     fn call(&mut self, req: ServiceRequest) -> Self::Future {
         // negotiate content-encoding
         let encoding = if let Some(val) = req.headers().get(&ACCEPT_ENCODING) {

src/middleware/defaultheaders.rs

@@ -125,6 +125,7 @@ where
         self.service.poll_ready()
     }
 
+    #[allow(clippy::borrow_interior_mutable_const)]
     fn call(&mut self, req: ServiceRequest) -> Self::Future {
         let inner = self.inner.clone();
 

src/middleware/logger.rs

@@ -415,9 +415,9 @@ impl FormatText {
                     ))
                 };
             }
-            FormatText::UrlPath => *self = FormatText::Str(format!("{}", req.path())),
+            FormatText::UrlPath => *self = FormatText::Str(req.path().to_string()),
             FormatText::RequestTime => {
-                *self = FormatText::Str(format!("{}", now.rfc3339()))
+                *self = FormatText::Str(now.rfc3339().to_string())
             }
             FormatText::RequestHeader(ref name) => {
                 let s = if let Some(val) = req.headers().get(name) {