Merge branch 'kisamoto-62_add-service-plan-context'

[#164389015]

Co-authored-by: Derik Evangelista <devangelista@pivotal.io>

README.md

@@ -50,6 +50,27 @@ use the `NewFailureResponseBuilder()` to add a custom `Error:` value in the
 response, or indicate that the broker should return an empty response rather
 than the error message.
 
+## Request Context
+
+When provisioning a service `brokerapi` validates the `service_id` and `plan_id`
+in the request, attaching the found instances to the request Context. These
+values can be retrieved in a `brokerapi.ServiceBroker` implementation using 
+utility methods `RetrieveServiceFromContext` and `RetrieveServicePlanFromContext`
+as shown below.
+
+```golang
+func (sb *ServiceBrokerImplementation) Provision(ctx context.Context,
+  instanceID string, details brokerapi.ProvisionDetails, asyncAllowed bool) {
+
+  service := brokerapi.RetrieveServiceFromContext(ctx)
+  if service == nil {
+    // Lookup service
+  }
+
+  // [..]
+}
+```
+
 ## Originating Identity
 
 The request context for every request contains the unparsed

api.go

@@ -19,10 +19,11 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"github.com/pivotal-cf/brokerapi/middlewares/originating_identity_header"
 	"net/http"
 	"strconv"
 
+	"github.com/pivotal-cf/brokerapi/middlewares/originating_identity_header"
+
 	"code.cloudfoundry.org/lager"
 	"github.com/gorilla/mux"
 	"github.com/pivotal-cf/brokerapi/auth"
@@ -183,6 +184,7 @@ func (h serviceBrokerHandler) provision(w http.ResponseWriter, req *http.Request
 	services, _ := h.serviceBroker.Services(req.Context())
 	for _, service := range services {
 		if service.ID == details.ServiceID {
+			req = req.WithContext(AddServiceToContext(req.Context(), &service))
 			valid = true
 			break
 		}
@@ -199,6 +201,7 @@ func (h serviceBrokerHandler) provision(w http.ResponseWriter, req *http.Request
 	for _, service := range services {
 		for _, plan := range service.Plans {
 			if plan.ID == details.PlanID {
+				req = req.WithContext(AddServicePlanToContext(req.Context(), &plan))
 				valid = true
 				break
 			}
@@ -797,4 +800,4 @@ func checkBrokerAPIVersionHdr(req *http.Request) (brokerVersion, error) {
 		return version, errors.New("X-Broker-API-Version Header must be 2.x")
 	}
 	return version, nil
-}
+}

context_utils.go

@@ -0,0 +1,38 @@
+package brokerapi
+
+import "context"
+
+type contextKey string
+
+const (
+	contextKeyService contextKey = "brokerapi_service"
+	contextKeyPlan    contextKey = "brokerapi_plan"
+)
+
+func AddServiceToContext(ctx context.Context, service *Service) context.Context {
+	if service != nil {
+		return context.WithValue(ctx, contextKeyService, service)
+	}
+	return ctx
+}
+
+func RetrieveServiceFromContext(ctx context.Context) *Service {
+	if value := ctx.Value(contextKeyService); value != nil {
+		return value.(*Service)
+	}
+	return nil
+}
+
+func AddServicePlanToContext(ctx context.Context, plan *ServicePlan) context.Context {
+	if plan != nil {
+		return context.WithValue(ctx, contextKeyPlan, plan)
+	}
+	return ctx
+}
+
+func RetrieveServicePlanFromContext(ctx context.Context) *ServicePlan {
+	if value := ctx.Value(contextKeyPlan); value != nil {
+		return value.(*ServicePlan)
+	}
+	return nil
+}

context_utils_test.go

@@ -0,0 +1,77 @@
+package brokerapi_test
+
+import (
+	"context"
+
+	. "github.com/onsi/ginkgo"
+	. "github.com/onsi/gomega"
+
+	"github.com/pivotal-cf/brokerapi"
+)
+
+var _ = Describe("Context Utilities", func() {
+
+	type testContextKey string
+
+	var (
+		ctx                   context.Context
+		contextValidatorKey   testContextKey
+		contextValidatorValue string
+	)
+
+	BeforeEach(func() {
+		contextValidatorKey = "context-utilities-test"
+		contextValidatorValue = "original"
+		ctx = context.Background()
+		ctx = context.WithValue(ctx, contextValidatorKey, contextValidatorValue)
+	})
+
+	Describe("Service Context", func() {
+		Context("when the service is nil", func() {
+			It("returns the original context", func() {
+				ctx = brokerapi.AddServiceToContext(ctx, nil)
+				Expect(ctx.Err()).To(BeZero())
+				Expect(brokerapi.RetrieveServiceFromContext(ctx)).To(BeZero())
+				Expect(ctx.Value(contextValidatorKey).(string)).To(Equal(contextValidatorValue))
+			})
+		})
+
+		Context("when the service is valid", func() {
+			It("sets and receives the service in the context", func() {
+				service := &brokerapi.Service{
+					ID:   "9A3095D7-ED3C-45FA-BC9F-592820628723",
+					Name: "Test Service",
+				}
+				ctx = brokerapi.AddServiceToContext(ctx, service)
+				Expect(ctx.Err()).To(BeZero())
+				Expect(ctx.Value(contextValidatorKey).(string)).To(Equal(contextValidatorValue))
+				Expect(brokerapi.RetrieveServiceFromContext(ctx).ID).To(Equal(service.ID))
+				Expect(brokerapi.RetrieveServiceFromContext(ctx).Name).To(Equal(service.Name))
+				Expect(brokerapi.RetrieveServiceFromContext(ctx).Metadata).To(BeZero())
+			})
+		})
+	})
+
+	Describe("Plan Context", func() {
+		Context("when the service plan is nil", func() {
+			It("returns the original context", func() {
+				ctx = brokerapi.AddServicePlanToContext(ctx, nil)
+				Expect(ctx.Err()).To(BeZero())
+				Expect(brokerapi.RetrieveServicePlanFromContext(ctx)).To(BeZero())
+				Expect(ctx.Value(contextValidatorKey).(string)).To(Equal(contextValidatorValue))
+			})
+		})
+
+		Context("when the service plan is valid", func() {
+			It("sets and retrieves the service plan in the context", func() {
+				plan := &brokerapi.ServicePlan{
+					ID: "AC257573-8C62-4B1A-AC34-ECA3863F50EC",
+				}
+				ctx = brokerapi.AddServicePlanToContext(ctx, plan)
+				Expect(ctx.Err()).To(BeZero())
+				Expect(ctx.Value(contextValidatorKey).(string)).To(Equal(contextValidatorValue))
+				Expect(brokerapi.RetrieveServicePlanFromContext(ctx).ID).To(Equal(plan.ID))
+			})
+		})
+	})
+})