wip: add more middleware examples

http/middleware/README.md

@@ -89,6 +89,27 @@ func recoverPanics(next http.Handler) http.Handler {
 }
 ```
 
+#### Example: Panic handler
+
+```go
+func RecoverPanics(next http.HandlerFunc) http.HandlerFunc {
+    return func(w http.ResponseWriter, r *http.Request) {
+        defer func() {
+            if _err := recover(); _err != nil {
+                err, ok := _err.(error)
+                if !ok {
+                    err = fmt.Errorf("%v", _err)
+                }
+                api.InternalError(w, r, err)
+                return
+            }
+        }()
+
+        next.ServeHTTP(w, r)
+    }
+}
+```
+
 #### Example: Request logger
 
 ```go
@@ -121,7 +142,10 @@ func basicAuth(next http.Handler) http.Handler {
          return
       }
 
-      next.ServeHTTP(w, r)
+      ctx := r.Context()
+      ctx = context.WithValue(ctx, UsernameKey, username)
+      next.ServeHTTP(w, r.WithContext(ctx))
+      // or just next.ServeHTTP(w, r)
    }
 }
 ```

http/middleware/basicauth.go

@@ -0,0 +1,30 @@
+package middleware
+
+import (
+	"context"
+	"net/http"
+)
+
+type BasicAuthVerifier interface {
+	Verify(string, string) bool
+}
+
+type usernameKeyType struct{}
+
+var UsernameKey usernameKeyType
+
+func BasicAuth(v BasicAuthVerifier) func(http.HandlerFunc) http.HandlerFunc {
+	return func(next http.HandlerFunc) http.HandlerFunc {
+		return func(w http.ResponseWriter, r *http.Request) {
+			username, password, ok := r.BasicAuth()
+			if !ok || !v.Verify(username, password) {
+				// s.jsonError(w, http.StatusUnauthorized, "unauthorized", "Unauthorized", "Invalid credentials")
+				return
+			}
+
+			ctx := r.Context()
+			ctx = context.WithValue(ctx, UsernameKey, username)
+			next.ServeHTTP(w, r.WithContext(ctx))
+		}
+	}
+}

http/middleware/middleware.go

@@ -12,6 +12,7 @@
 package middleware
 
 import (
+	"errors"
 	"net/http"
 	"slices"
 )
@@ -33,7 +34,7 @@ type MiddlewareChain struct {
 // Handle composes middleware with the final handler
 func (c MiddlewareChain) Handle(handler http.Handler) http.Handler {
 	if handler == nil {
-		panic("mw.New(...).Use(...).Handle(-->this<--) requires a handler")
+		panic(errors.New("mw.New(...).Use(...).Handle(-->this<--) requires a handler"))
 	}
 
 	middlewares := make([]Middleware, len(c.middlewares))
@@ -86,7 +87,7 @@ func (c MiddlewareMux) HandleFunc(path string, handler http.HandlerFunc) {
 // Handle composes middleware with the final handler
 func (c MiddlewareMux) handle(handler http.Handler) http.Handler {
 	if handler == nil {
-		panic("mw.New(...).Use(...).Handle(-->this<--) requires a handler")
+		panic(errors.New("mw.New(...).Use(...).Handle(-->this<--) requires a handler"))
 	}
 
 	middlewares := make([]Middleware, len(c.middlewares))