Add request scope middleware

pkg/apis/middleware/scope.go

@@ -0,0 +1,24 @@
+package middleware
+
+import (
+	"github.com/oauth2-proxy/oauth2-proxy/pkg/apis/sessions"
+)
+
+// RequestScope contains information regarding the request that is being made.
+// The RequestScope is used to pass information between different middlewares
+// within the chain.
+type RequestScope struct {
+	// Session details the authenticated users information (if it exists).
+	Session *sessions.SessionState
+
+	// SaveSession indicates whether the session storage should attempt to save
+	// the session or not.
+	SaveSession bool
+
+	// ClearSession indicates whether the user should be logged out or not.
+	ClearSession bool
+
+	// SessionRevalidated indicates whether the session has been revalidated since
+	// it was loaded or not.
+	SessionRevalidated bool
+}

pkg/middleware/scope.go

@@ -0,0 +1,39 @@
+package middleware
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/justinas/alice"
+	middlewareapi "github.com/oauth2-proxy/oauth2-proxy/pkg/apis/middleware"
+)
+
+type scopeKey string
+
+// requestScopeKey uses a typed string to reduce likelihood of clasing
+// with other context keys
+const requestScopeKey scopeKey = "request-scope"
+
+func NewScope() alice.Constructor {
+	return addScope
+}
+
+// addScope injects a new request scope into the request context.
+func addScope(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
+		scope := &middlewareapi.RequestScope{}
+		contextWithScope := context.WithValue(req.Context(), requestScopeKey, scope)
+		requestWithScope := req.WithContext(contextWithScope)
+		next.ServeHTTP(rw, requestWithScope)
+	})
+}
+
+// GetRequestScope returns the current request scope from the given request
+func GetRequestScope(req *http.Request) *middlewareapi.RequestScope {
+	scope := req.Context().Value(requestScopeKey)
+	if scope == nil {
+		return nil
+	}
+
+	return scope.(*middlewareapi.RequestScope)
+}

pkg/middleware/scope_test.go

@@ -0,0 +1,94 @@
+package middleware
+
+import (
+	"context"
+	"net/http"
+	"net/http/httptest"
+
+	middlewareapi "github.com/oauth2-proxy/oauth2-proxy/pkg/apis/middleware"
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+)
+
+var _ = Describe("Scope Suite", func() {
+	Context("NewScope", func() {
+		var request, nextRequest *http.Request
+		var rw http.ResponseWriter
+
+		BeforeEach(func() {
+			var err error
+			request, err = http.NewRequest("", "http://127.0.0.1/", nil)
+			Expect(err).ToNot(HaveOccurred())
+
+			rw = httptest.NewRecorder()
+
+			handler := NewScope()(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				nextRequest = r
+				w.WriteHeader(200)
+			}))
+			handler.ServeHTTP(rw, request)
+		})
+
+		It("does not add a scope to the original request", func() {
+			Expect(request.Context().Value(requestScopeKey)).To(BeNil())
+		})
+
+		It("cannot load a scope from the original request using GetRequestScope", func() {
+			Expect(GetRequestScope(request)).To(BeNil())
+		})
+
+		It("adds a scope to the request for the next handler", func() {
+			Expect(nextRequest.Context().Value(requestScopeKey)).ToNot(BeNil())
+		})
+
+		It("can load a scope from the next handler's request using GetRequestScope", func() {
+			Expect(GetRequestScope(nextRequest)).ToNot(BeNil())
+		})
+	})
+
+	Context("GetRequestScope", func() {
+		var request *http.Request
+
+		BeforeEach(func() {
+			var err error
+			request, err = http.NewRequest("", "http://127.0.0.1/", nil)
+			Expect(err).ToNot(HaveOccurred())
+		})
+
+		Context("with a scope", func() {
+			var scope *middlewareapi.RequestScope
+
+			BeforeEach(func() {
+				scope = &middlewareapi.RequestScope{}
+				contextWithScope := context.WithValue(request.Context(), requestScopeKey, scope)
+				request = request.WithContext(contextWithScope)
+			})
+
+			It("returns the scope", func() {
+				s := GetRequestScope(request)
+				Expect(s).ToNot(BeNil())
+				Expect(s).To(Equal(scope))
+			})
+
+			Context("if the scope is then modified", func() {
+				BeforeEach(func() {
+					Expect(scope.SaveSession).To(BeFalse())
+					scope.SaveSession = true
+				})
+
+				It("returns the updated session", func() {
+					s := GetRequestScope(request)
+					Expect(s).ToNot(BeNil())
+					Expect(s).To(Equal(scope))
+					Expect(s.SaveSession).To(BeTrue())
+				})
+			})
+		})
+
+		Context("without a scope", func() {
+			It("returns nil", func() {
+				Expect(GetRequestScope(request)).To(BeNil())
+			})
+		})
+	})
+})