From da69b50b92b37ececfd7b9d63092b8f344740ffe Mon Sep 17 00:00:00 2001
From: johnabass <johnbass1017@yahoo.com>
Date: Thu, 15 Aug 2024 15:05:19 -0700
Subject: [PATCH] simplified workflow setup for HTTP middleware

---
 basculehttp/authenticator.go            | 16 +++++++++++++++
 basculehttp/authorizer.go               | 16 +++++++++++++++
 basculehttp/middleware.go               | 26 ++++++++++++++++++++++++-
 basculehttp/middleware_examples_test.go | 25 ++++++++++--------------
 4 files changed, 67 insertions(+), 16 deletions(-)
 create mode 100644 basculehttp/authenticator.go
 create mode 100644 basculehttp/authorizer.go

diff --git a/basculehttp/authenticator.go b/basculehttp/authenticator.go
new file mode 100644
index 0000000..e91218c
--- /dev/null
+++ b/basculehttp/authenticator.go
@@ -0,0 +1,16 @@
+// SPDX-FileCopyrightText: 2024 Comcast Cable Communications Management, LLC
+// SPDX-License-Identifier: Apache-2.0
+
+package basculehttp
+
+import (
+	"net/http"
+
+	"github.com/xmidt-org/bascule/v1"
+)
+
+// NewAuthenticator is a convenient wrapper around bascule.NewAuthenticator.
+// This function eases the syntactical pain of generics when creating Middleware.
+func NewAuthenticator(opts ...bascule.AuthenticatorOption[*http.Request]) (*bascule.Authenticator[*http.Request], error) {
+	return bascule.NewAuthenticator(opts...)
+}
diff --git a/basculehttp/authorizer.go b/basculehttp/authorizer.go
new file mode 100644
index 0000000..89e0e2e
--- /dev/null
+++ b/basculehttp/authorizer.go
@@ -0,0 +1,16 @@
+// SPDX-FileCopyrightText: 2024 Comcast Cable Communications Management, LLC
+// SPDX-License-Identifier: Apache-2.0
+
+package basculehttp
+
+import (
+	"net/http"
+
+	"github.com/xmidt-org/bascule/v1"
+)
+
+// NewAuthorizer is a convenient wrapper around bascule.NewAuthorizer.
+// This function eases the syntactical pain of generics when creating Middleware.
+func NewAuthorizer(opts ...bascule.AuthorizerOption[*http.Request]) (*bascule.Authorizer[*http.Request], error) {
+	return bascule.NewAuthorizer(opts...)
+}
diff --git a/basculehttp/middleware.go b/basculehttp/middleware.go
index c2cf69b..6f6348a 100644
--- a/basculehttp/middleware.go
+++ b/basculehttp/middleware.go
@@ -24,9 +24,22 @@ func (mof middlewareOptionFunc) apply(m *Middleware) error {
 
 // WithAuthenticator supplies the Authenticator workflow for the middleware.
 //
-// If no authenticator is supplied, NewMiddeware returns an error.
+// Note: If no authenticator is supplied, NewMiddeware returns an error.
 func WithAuthenticator(authenticator *bascule.Authenticator[*http.Request]) MiddlewareOption {
+	return UseAuthenticator(authenticator, nil)
+}
+
+// UseAuthenticator is a variant of WithAuthenticator that allows a caller to
+// nest function calls a little easier.  The output of NewAuthenticator
+// can be passed directly to this option.
+//
+// Note: If no authenticator is supplied, NewMiddeware returns an error.
+func UseAuthenticator(authenticator *bascule.Authenticator[*http.Request], err error) MiddlewareOption {
 	return middlewareOptionFunc(func(m *Middleware) error {
+		if err != nil {
+			return err
+		}
+
 		m.authenticator = authenticator
 		return nil
 	})
@@ -37,7 +50,18 @@ func WithAuthenticator(authenticator *bascule.Authenticator[*http.Request]) Midd
 // The Authorizer is optional.  If no authorizer is supplied, then no authorization
 // takes place and no authorization events are fired.
 func WithAuthorizer(authorizer *bascule.Authorizer[*http.Request]) MiddlewareOption {
+	return UseAuthorizer(authorizer, nil)
+}
+
+// UseAuthorizer is a variant of WithAuthorizer that allows a caller to
+// nest function calls a little easier.  The output of NewAuthorizer
+// can be passed directly to this option.
+func UseAuthorizer(authorizer *bascule.Authorizer[*http.Request], err error) MiddlewareOption {
 	return middlewareOptionFunc(func(m *Middleware) error {
+		if err != nil {
+			return err
+		}
+
 		m.authorizer = authorizer
 		return nil
 	})
diff --git a/basculehttp/middleware_examples_test.go b/basculehttp/middleware_examples_test.go
index 240713d..742844c 100644
--- a/basculehttp/middleware_examples_test.go
+++ b/basculehttp/middleware_examples_test.go
@@ -18,27 +18,22 @@ func ExampleMiddleware_basicauth() {
 		WithScheme(SchemeBasic, BasicTokenParser{}),
 	)
 
-	a, _ := bascule.NewAuthenticator(
-		bascule.WithTokenParsers(tp),
+	m, _ := NewMiddleware(
+		UseAuthenticator(
+			NewAuthenticator(
+				bascule.WithTokenParsers(tp),
+			),
+		),
 	)
 
-	m, err := NewMiddleware(
-		WithAuthenticator(a),
-	)
-
-	if err != nil {
-		panic(err)
-	}
-
 	// decorate a handler that needs authorization
 	h := m.ThenFunc(
 		func(response http.ResponseWriter, request *http.Request) {
-			t, ok := bascule.GetFrom(request)
-			if !ok {
-				panic("no token found")
+			if t, ok := bascule.GetFrom(request); ok {
+				fmt.Println("principal:", t.Principal())
+			} else {
+				fmt.Println("no token found")
 			}
-
-			fmt.Println("principal:", t.Principal())
 		},
 	)