Update doc comments

src/extractors.rs

@@ -1,15 +1,17 @@
 use axum::{extract::FromRequestParts, http::request::Parts};
 
 use crate::{
-    HX_BOOSTED, HX_CURRENT_URL, HX_HISTORY_RESTORE_REQUEST, HX_PROMPT, HX_TARGET, HX_TRIGGER,
-    HX_TRIGGER_NAME,
+    HX_BOOSTED, HX_CURRENT_URL, HX_HISTORY_RESTORE_REQUEST, HX_PROMPT, HX_REQUEST, HX_TARGET,
+    HX_TRIGGER, HX_TRIGGER_NAME,
 };
 
-/// The `HX-Boosted` header. This header is set when a request is made with the
-/// "hx-boost" attribute is set on an element.
+/// The `HX-Boosted` header.
 ///
-/// This extractor does not fail if no header is present, instead returning a
-/// `false` value.
+/// This is set when a request is made from an element where its parent has the
+/// `hx-boost` attribute set to `true`.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `false`.
 ///
 /// See <https://htmx.org/attributes/hx-boost/> for more information.
 #[derive(Debug, Clone, Copy)]
@@ -31,8 +33,15 @@ where
     }
 }
 
+/// The `HX-Current-Url` header.
+///
+/// This is set on every request made by htmx itself. As its name implies, it
+/// just contains the current url.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `None`.
 #[derive(Debug, Clone)]
-pub struct HxCurrentUrl(pub String);
+pub struct HxCurrentUrl(pub Option<String>);
 
 #[axum::async_trait]
 impl<S> FromRequestParts<S> for HxCurrentUrl
@@ -44,14 +53,18 @@ where
     async fn from_request_parts(parts: &mut Parts, _: &S) -> Result<Self, Self::Rejection> {
         if let Some(url) = parts.headers.get(HX_CURRENT_URL) {
             if let Ok(url) = url.to_str() {
-                return Ok(HxCurrentUrl(url.to_string()));
+                return Ok(HxCurrentUrl(Some(url.to_string())));
             }
         }
 
-        return Ok(HxCurrentUrl("".to_string()));
+        return Ok(HxCurrentUrl(None));
     }
 }
 
+/// The `HX-History-Restore-Request` header.
+///
+/// This extractor will always return a value. If the header is not present,
+/// it will return `false`.
 pub struct HxHistoryRestoreRequest(pub bool);
 
 #[axum::async_trait]
@@ -70,6 +83,13 @@ where
     }
 }
 
+/// The `HX-Prompt` header.
+///
+/// This is set when a request is made from an element that has the `hx-prompt`
+/// attribute set. The value will contain the string input by the user.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `None`.
 #[derive(Debug, Clone)]
 pub struct HxPrompt(pub Option<String>);
 
@@ -91,6 +111,13 @@ where
     }
 }
 
+/// The `HX-Request` header.
+///
+/// This is set on every request made by htmx itself. It won't be present on
+/// requests made manually, or by other libraries.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `false`.
 #[derive(Debug, Clone, Copy)]
 pub struct HxRequest(pub bool);
 
@@ -101,11 +128,23 @@ where
 {
     type Rejection = std::convert::Infallible;
 
-    async fn from_request_parts(_: &mut Parts, _: &S) -> Result<Self, Self::Rejection> {
+    async fn from_request_parts(parts: &mut Parts, _: &S) -> Result<Self, Self::Rejection> {
+        if parts.headers.contains_key(HX_REQUEST) {
             return Ok(HxRequest(true));
+        } else {
+            return Ok(HxRequest(false));
+        }
     }
 }
 
+/// The `HX-Target` header.
+///
+/// This is set when a request is made from an element that has the `hx-target`
+/// attribute set. The value will contain the target element's id. If the
+/// id does not exist on the page, the value will be None.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `None`.
 #[derive(Debug, Clone)]
 pub struct HxTarget(pub Option<String>);
 
@@ -127,6 +166,14 @@ where
     }
 }
 
+/// The `HX-Trigger-Name` header.
+///
+/// This is set when a request is made from an element that has the `hx-trigger`
+/// attribute set. The value will contain the trigger element's name. If the
+/// name does not exist on the page, the value will be None.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `None`.
 #[derive(Debug, Clone)]
 pub struct HxTriggerName(pub Option<String>);
 
@@ -148,6 +195,14 @@ where
     }
 }
 
+/// The `HX-Trigger` header.
+///
+/// This is set when a request is made from an element that has the `hx-trigger`
+/// attribute set. The value will contain the trigger element's id. If the
+/// id does not exist on the page, the value will be None.
+///
+/// This extractor will always return a value. If the header is not present, it
+/// will return `None`.
 #[derive(Debug, Clone)]
 pub struct HxTrigger(pub Option<String>);