refact(plugin): Move host loopback plugin into internal/plugin/loopback

internal/plugin/loopback/options.go

@@ -0,0 +1,69 @@
+// Copyright (c) HashiCorp, Inc.
+// SPDX-License-Identifier: MPL-2.0
+
+package loopback
+
+import (
+	"github.com/hashicorp/boundary/sdk/pbs/controller/api/resources/storagebuckets"
+	"google.golang.org/grpc/codes"
+)
+
+// PluginMockError is used to mock an error when interacting with an external object store.
+type PluginMockError struct {
+	bucketName   string
+	bucketPrefix string
+	objectKey    string
+	errMsg       string
+	errCode      codes.Code
+}
+
+func (e PluginMockError) match(bucket *storagebuckets.StorageBucket, key string) bool {
+	if key != "" && e.objectKey != key {
+		return false
+	}
+	if e.bucketName != bucket.BucketName {
+		return false
+	}
+	if bucket.BucketPrefix != "" && e.bucketPrefix != bucket.BucketPrefix {
+		return false
+	}
+	return true
+}
+
+type TestOption func(*TestOptions) error
+
+type TestOptions struct {
+	withMockBuckets map[BucketName]Bucket
+	withMockError   []PluginMockError
+}
+
+// getTestOpts - iterate the inbound Options and return a struct
+func getTestOpts(opt ...TestOption) (TestOptions, error) {
+	opts := getDefaultTestOptions()
+	for _, o := range opt {
+		if err := o(&opts); err != nil {
+			return opts, err
+		}
+	}
+	return opts, nil
+}
+
+func getDefaultTestOptions() TestOptions {
+	return TestOptions{}
+}
+
+// WithMockBuckets provides an option to create mocked external object store buckets.
+func WithMockBuckets(buckets map[BucketName]Bucket) TestOption {
+	return func(o *TestOptions) error {
+		o.withMockBuckets = buckets
+		return nil
+	}
+}
+
+// WithMockError provides an option to mock an error when interacting with an external object store.
+func WithMockError(err PluginMockError) TestOption {
+	return func(o *TestOptions) error {
+		o.withMockError = append(o.withMockError, err)
+		return nil
+	}
+}