support interfaces for the generated code

pkg/cloudprovider/providers/gce/cloud/project.go

@@ -0,0 +1,44 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloud
+
+import (
+	"context"
+
+	"k8s.io/kubernetes/pkg/cloudprovider/providers/gce/cloud/meta"
+)
+
+// ProjectRouter routes service calls to the appropriate GCE project.
+type ProjectRouter interface {
+	// ProjectID returns the project ID (non-numeric) to be used for a call
+	// to an API (version,service). Example tuples: ("ga", "ForwardingRules"),
+	// ("alpha", "GlobalAddresses").
+	//
+	// This allows for plumbing different service calls to the appropriate
+	// project, for instance, networking services to a separate project
+	// than instance management.
+	ProjectID(ctx context.Context, version meta.Version, service string) string
+}
+
+// SingleProjectRouter routes all service calls to the same project ID.
+type SingleProjectRouter struct {
+	ID string
+}
+
+func (r *SingleProjectRouter) ProjectID(ctx context.Context, version meta.Version, service string) string {
+	return r.ID
+}

pkg/cloudprovider/providers/gce/cloud/ratelimit.go

@@ -0,0 +1,67 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloud
+
+import (
+	"context"
+	"time"
+
+	"k8s.io/kubernetes/pkg/cloudprovider/providers/gce/cloud/meta"
+)
+
+// RateLimitKey is a key identifying the operation to be rate limited. The rate limit
+// queue will be determined based on the contents of RateKey.
+type RateLimitKey struct {
+	// ProjectID is the non-numeric ID of the project.
+	ProjectID string
+	// Operation is the specific method being invoked (e.g. "Get", "List").
+	Operation string
+	// Version is the API version of the call.
+	Version meta.Version
+	// Service is the service being invoked (e.g. "Firewalls", "BackendServices")
+	Service string
+}
+
+// RateLimiter is the interface for a rate limiting policy.
+type RateLimiter interface {
+	// Accept uses the RateLimitKey to derive a sleep time for the calling
+	// goroutine. This call will block until the operation is ready for
+	// execution.
+	//
+	// Accept returns an error if the given context ctx was canceled
+	// while waiting for acceptance into the queue.
+	Accept(ctx context.Context, key *RateLimitKey) error
+}
+
+// NopRateLimiter is a rate limiter that performs no rate limiting.
+type NopRateLimiter struct {
+}
+
+func (*NopRateLimiter) Accept(ctx context.Context, key *RateLimitKey) error {
+	// Rate limit polling of the Operation status to avoid hammering GCE
+	// for the status of an operation.
+	const pollTime = time.Duration(1) * time.Second
+	if key.Operation == "Get" && key.Service == "Operations" {
+		select {
+		case <-time.NewTimer(pollTime).C:
+			break
+		case <-ctx.Done():
+			return ctx.Err()
+		}
+	}
+	return nil
+}

pkg/cloudprovider/providers/gce/cloud/service.go

@@ -0,0 +1,79 @@
+/*
+Copyright 2017 The Kubernetes Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package cloud
+
+import (
+	"context"
+	"fmt"
+
+	alpha "google.golang.org/api/compute/v0.alpha"
+	beta "google.golang.org/api/compute/v0.beta"
+	ga "google.golang.org/api/compute/v1"
+)
+
+// Service is the top-level adapter for all of the different compute API
+// versions.
+type Service struct {
+	GA            *ga.Service
+	Alpha         *alpha.Service
+	Beta          *beta.Service
+	ProjectRouter ProjectRouter
+	RateLimiter   RateLimiter
+}
+
+// wrapOperation wraps a GCE anyOP in a version generic operation type.
+func (g *Service) wrapOperation(anyOp interface{}) (operation, error) {
+	switch o := anyOp.(type) {
+	case *ga.Operation:
+		r, err := ParseResourceURL(o.SelfLink)
+		if err != nil {
+			return nil, err
+		}
+		return &gaOperation{g, o, r.ProjectID}, nil
+	case *alpha.Operation:
+		r, err := ParseResourceURL(o.SelfLink)
+		if err != nil {
+			return nil, err
+		}
+		return &alphaOperation{g, o, r.ProjectID}, nil
+	case *beta.Operation:
+		r, err := ParseResourceURL(o.SelfLink)
+		if err != nil {
+			return nil, err
+		}
+		return &betaOperation{g, o, r.ProjectID}, nil
+	default:
+		return nil, fmt.Errorf("invalid type %T", anyOp)
+	}
+}
+
+// WaitForCompletion of a long running operation. This will poll the state of
+// GCE for the completion status of the given operation. genericOp can be one
+// of alpha, beta, ga Operation types.
+func (g *Service) WaitForCompletion(ctx context.Context, genericOp interface{}) error {
+	op, err := g.wrapOperation(genericOp)
+	if err != nil {
+		return err
+	}
+	for done, err := op.isDone(ctx); !done; done, err = op.isDone(ctx) {
+		if err != nil {
+			return err
+		}
+		g.RateLimiter.Accept(ctx, op.rateLimitKey())
+	}
+	return nil
+}