add inspect mapper

src/mappers.rs

@@ -96,20 +96,20 @@ where
 }
 
 /// Call Deref::deref() on the input and pass it to the next mapper.
-pub fn deref<C>(inner: C) -> Deref<C> {
+pub fn deref<M>(inner: M) -> Deref<M> {
     Deref(inner)
 }
 /// The `Deref` mapper returned by [deref()](fn.deref.html)
 #[derive(Debug)]
-pub struct Deref<C>(C);
-impl<C, IN> Mapper<IN> for Deref<C>
+pub struct Deref<M>(M);
+impl<M, IN> Mapper<IN> for Deref<M>
 where
-    C: Mapper<IN::Target>,
+    M: Mapper<IN::Target>,
     IN: std::ops::Deref,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &IN) -> C::Out {
+    fn map(&mut self, input: &IN) -> M::Out {
         self.0.map(input.deref())
     }
 }
@@ -162,14 +162,14 @@ where
 }
 
 /// invert the result of the inner mapper.
-pub fn not<C>(inner: C) -> Not<C> {
+pub fn not<M>(inner: M) -> Not<M> {
     Not(inner)
 }
 /// The `Not` mapper returned by [not()](fn.not.html)
-pub struct Not<C>(C);
-impl<C, IN> Mapper<IN> for Not<C>
+pub struct Not<M>(M);
+impl<M, IN> Mapper<IN> for Not<M>
 where
-    C: Mapper<IN, Out = bool>,
+    M: Mapper<IN, Out = bool>,
     IN: ?Sized,
 {
     type Out = bool;
@@ -178,9 +178,9 @@ where
         !self.0.map(input)
     }
 }
-impl<C> fmt::Debug for Not<C>
+impl<M> fmt::Debug for Not<M>
 where
-    C: fmt::Debug,
+    M: fmt::Debug,
 {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         write!(f, "Not({:?})", &self.0)
@@ -237,20 +237,20 @@ where
 }
 
 /// url decode the input and pass the resulting slice of key-value pairs to the next mapper.
-pub fn url_decoded<C>(inner: C) -> UrlDecoded<C> {
+pub fn url_decoded<M>(inner: M) -> UrlDecoded<M> {
     UrlDecoded(inner)
 }
 /// The `UrlDecoded` mapper returned by [url_decoded()](fn.url_decoded.html)
 #[derive(Debug)]
-pub struct UrlDecoded<C>(C);
-impl<IN, C> Mapper<IN> for UrlDecoded<C>
+pub struct UrlDecoded<M>(M);
+impl<IN, M> Mapper<IN> for UrlDecoded<M>
 where
     IN: AsRef<[u8]> + ?Sized,
-    C: Mapper<[(String, String)]>,
+    M: Mapper<[(String, String)]>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &IN) -> C::Out {
+    fn map(&mut self, input: &IN) -> M::Out {
         let decoded: Vec<(String, String)> = url::form_urlencoded::parse(input.as_ref())
             .into_owned()
             .collect();
@@ -263,20 +263,20 @@ where
 ///
 /// If the input can't be decoded a serde_json::Value::Null is passed to the next
 /// mapper.
-pub fn json_decoded<C>(inner: C) -> JsonDecoded<C> {
+pub fn json_decoded<M>(inner: M) -> JsonDecoded<M> {
     JsonDecoded(inner)
 }
 /// The `JsonDecoded` mapper returned by [json_decoded()](fn.json_decoded.html)
 #[derive(Debug)]
-pub struct JsonDecoded<C>(C);
-impl<IN, C> Mapper<IN> for JsonDecoded<C>
+pub struct JsonDecoded<M>(M);
+impl<IN, M> Mapper<IN> for JsonDecoded<M>
 where
     IN: AsRef<[u8]> + ?Sized,
-    C: Mapper<serde_json::Value>,
+    M: Mapper<serde_json::Value>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &IN) -> C::Out {
+    fn map(&mut self, input: &IN) -> M::Out {
         let json_value: serde_json::Value =
             serde_json::from_slice(input.as_ref()).unwrap_or(serde_json::Value::Null);
         self.0.map(&json_value)
@@ -284,23 +284,20 @@ where
 }
 
 /// lowercase the input and pass it to the next mapper.
-pub fn lowercase<C>(inner: C) -> Lowercase<C>
-where
-    C: Mapper<[u8]>,
-{
+pub fn lowercase<M>(inner: M) -> Lowercase<M> {
     Lowercase(inner)
 }
 /// The `Lowercase` mapper returned by [lowercase()](fn.lowercase.html)
 #[derive(Debug)]
-pub struct Lowercase<C>(C);
-impl<IN, C> Mapper<IN> for Lowercase<C>
+pub struct Lowercase<M>(M);
+impl<IN, M> Mapper<IN> for Lowercase<M>
 where
     IN: AsRef<[u8]> + ?Sized,
-    C: Mapper<[u8]>,
+    M: Mapper<[u8]>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &IN) -> C::Out {
+    fn map(&mut self, input: &IN) -> M::Out {
         use bstr::ByteSlice;
         self.0.map(&input.as_ref().to_lowercase())
     }
@@ -328,6 +325,31 @@ impl<F> fmt::Debug for MapFn<F> {
     }
 }
 
+/// inspect the input and pass it to the next mapper.
+///
+/// This logs the value as it passes it to the next mapper unchanged. Can be
+/// useful when troubleshooting why a matcher may not be working as intended.
+pub fn inspect<M>(inner: M) -> Inspect<M> {
+    Inspect(inner)
+}
+/// The `Inspect` mapper returned by [inspect()](fn.inspect.html)
+#[derive(Debug)]
+pub struct Inspect<M>(M);
+impl<IN, M> Mapper<IN> for Inspect<M>
+where
+    IN: fmt::Debug + ?Sized,
+    M: Mapper<IN>,
+    M::Out: fmt::Debug,
+{
+    type Out = M::Out;
+
+    fn map(&mut self, input: &IN) -> M::Out {
+        let output = self.0.map(input);
+        log::debug!("{:?}.map({:?}) == {:?}", self.0, input, output);
+        output
+    }
+}
+
 #[cfg(test)]
 mod tests {
     use super::*;
@@ -445,4 +467,12 @@ mod tests {
         assert_eq!(true, c.map(&0));
         assert_eq!(false, c.map(&11));
     }
+
+    #[test]
+    fn test_inspect() {
+        let _ = pretty_env_logger::try_init();
+        let mut c = inspect(lowercase(matches("^foobar$")));
+        assert_eq!(true, c.map("Foobar"));
+        assert_eq!(false, c.map("Foobar1"));
+    }
 }

src/mappers/request.rs

@@ -3,74 +3,74 @@
 use super::Mapper;
 
 /// Extract the method from the HTTP request and pass it to the next mapper.
-pub fn method<C>(inner: C) -> Method<C> {
+pub fn method<M>(inner: M) -> Method<M> {
     Method(inner)
 }
 /// The `Method` mapper returned by [method()](fn.method.html)
 #[derive(Debug)]
-pub struct Method<C>(C);
-impl<C, B> Mapper<hyper::Request<B>> for Method<C>
+pub struct Method<M>(M);
+impl<M, B> Mapper<hyper::Request<B>> for Method<M>
 where
-    C: Mapper<str>,
+    M: Mapper<str>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Request<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Request<B>) -> M::Out {
         self.0.map(input.method().as_str())
     }
 }
 
 /// Extract the path from the HTTP request and pass it to the next mapper.
-pub fn path<C>(inner: C) -> Path<C> {
+pub fn path<M>(inner: M) -> Path<M> {
     Path(inner)
 }
 /// The `Path` mapper returned by [path()](fn.path.html)
 #[derive(Debug)]
-pub struct Path<C>(C);
-impl<C, B> Mapper<hyper::Request<B>> for Path<C>
+pub struct Path<M>(M);
+impl<M, B> Mapper<hyper::Request<B>> for Path<M>
 where
-    C: Mapper<str>,
+    M: Mapper<str>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Request<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Request<B>) -> M::Out {
         self.0.map(input.uri().path())
     }
 }
 
 /// Extract the query from the HTTP request and pass it to the next mapper.
-pub fn query<C>(inner: C) -> Query<C> {
+pub fn query<M>(inner: M) -> Query<M> {
     Query(inner)
 }
 /// The `Query` mapper returned by [query()](fn.query.html)
 #[derive(Debug)]
-pub struct Query<C>(C);
-impl<C, B> Mapper<hyper::Request<B>> for Query<C>
+pub struct Query<M>(M);
+impl<M, B> Mapper<hyper::Request<B>> for Query<M>
 where
-    C: Mapper<str>,
+    M: Mapper<str>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Request<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Request<B>) -> M::Out {
         self.0.map(input.uri().query().unwrap_or(""))
     }
 }
 
 /// Extract the headers from the HTTP request and pass the sequence to the next
 /// mapper.
-pub fn headers<C>(inner: C) -> Headers<C> {
+pub fn headers<M>(inner: M) -> Headers<M> {
     Headers(inner)
 }
 /// The `Headers` mapper returned by [headers()](fn.headers.html)
 #[derive(Debug)]
-pub struct Headers<C>(C);
-impl<C, B> Mapper<hyper::Request<B>> for Headers<C>
+pub struct Headers<M>(M);
+impl<M, B> Mapper<hyper::Request<B>> for Headers<M>
 where
-    C: Mapper<[(Vec<u8>, Vec<u8>)]>,
+    M: Mapper<[(Vec<u8>, Vec<u8>)]>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Request<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Request<B>) -> M::Out {
         let headers: Vec<(Vec<u8>, Vec<u8>)> = input
             .headers()
             .iter()
@@ -81,20 +81,20 @@ where
 }
 
 /// Extract the body from the HTTP request and pass it to the next mapper.
-pub fn body<C>(inner: C) -> Body<C> {
+pub fn body<M>(inner: M) -> Body<M> {
     Body(inner)
 }
 /// The `Body` mapper returned by [body()](fn.body.html)
 #[derive(Debug)]
-pub struct Body<C>(C);
-impl<C, B> Mapper<hyper::Request<B>> for Body<C>
+pub struct Body<M>(M);
+impl<M, B> Mapper<hyper::Request<B>> for Body<M>
 where
     B: ToOwned,
-    C: Mapper<B::Owned>,
+    M: Mapper<B::Owned>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Request<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Request<B>) -> M::Out {
         self.0.map(&input.body().to_owned())
     }
 }

src/mappers/response.rs

@@ -3,38 +3,38 @@
 use super::Mapper;
 
 /// Extract the status code from the HTTP response and pass it to the next mapper.
-pub fn status_code<C>(inner: C) -> StatusCode<C> {
+pub fn status_code<M>(inner: M) -> StatusCode<M> {
     StatusCode(inner)
 }
 /// The `StatusCode` mapper returned by [status_code()](fn.status_code.html)
 #[derive(Debug)]
-pub struct StatusCode<C>(C);
-impl<C, B> Mapper<hyper::Response<B>> for StatusCode<C>
+pub struct StatusCode<M>(M);
+impl<M, B> Mapper<hyper::Response<B>> for StatusCode<M>
 where
-    C: Mapper<u16>,
+    M: Mapper<u16>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Response<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Response<B>) -> M::Out {
         self.0.map(&input.status().as_u16())
     }
 }
 
 /// Extract the headers from the HTTP response and pass the sequence to the next
 /// mapper.
-pub fn headers<C>(inner: C) -> Headers<C> {
+pub fn headers<M>(inner: M) -> Headers<M> {
     Headers(inner)
 }
 /// The `Headers` mapper returned by [headers()](fn.headers.html)
 #[derive(Debug)]
-pub struct Headers<C>(C);
-impl<C, B> Mapper<hyper::Response<B>> for Headers<C>
+pub struct Headers<M>(M);
+impl<M, B> Mapper<hyper::Response<B>> for Headers<M>
 where
-    C: Mapper<[(Vec<u8>, Vec<u8>)]>,
+    M: Mapper<[(Vec<u8>, Vec<u8>)]>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Response<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Response<B>) -> M::Out {
         let headers: Vec<(Vec<u8>, Vec<u8>)> = input
             .headers()
             .iter()
@@ -45,19 +45,19 @@ where
 }
 
 /// Extract the body from the HTTP response and pass it to the next mapper.
-pub fn body<C>(inner: C) -> Body<C> {
+pub fn body<M>(inner: M) -> Body<M> {
     Body(inner)
 }
 /// The `Body` mapper returned by [body()](fn.body.html)
 #[derive(Debug)]
-pub struct Body<C>(C);
-impl<C, B> Mapper<hyper::Response<B>> for Body<C>
+pub struct Body<M>(M);
+impl<M, B> Mapper<hyper::Response<B>> for Body<M>
 where
-    C: Mapper<B>,
+    M: Mapper<B>,
 {
-    type Out = C::Out;
+    type Out = M::Out;
 
-    fn map(&mut self, input: &hyper::Response<B>) -> C::Out {
+    fn map(&mut self, input: &hyper::Response<B>) -> M::Out {
         self.0.map(input.body())
     }
 }

src/mappers/sequence.rs

@@ -4,15 +4,15 @@ use super::Mapper;
 
 /// true if the provided mapper returns true for any of the elements in the
 /// sequence.
-pub fn contains<C>(inner: C) -> Contains<C> {
+pub fn contains<M>(inner: M) -> Contains<M> {
     Contains(inner)
 }
 /// The `Contains` mapper returned by [contains()](fn.contains.html)
 #[derive(Debug)]
-pub struct Contains<C>(C);
-impl<C, E> Mapper<[E]> for Contains<C>
+pub struct Contains<M>(M);
+impl<M, E> Mapper<[E]> for Contains<M>
 where
-    C: Mapper<E, Out = bool>,
+    M: Mapper<E, Out = bool>,
 {
     type Out = bool;