add a BackupStore to pkg/persistence that supports prefixes

Signed-off-by: Steve Kriss <steve@heptio.com>

pkg/cloudprovider/in_memory_object_store.go

@@ -0,0 +1,168 @@
+/*
+Copyright 2018 the Heptio Ark contributors.
+
+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 cloudprovider
+
+import (
+	"bytes"
+	"errors"
+	"io"
+	"io/ioutil"
+	"strings"
+	"time"
+)
+
+type BucketData map[string][]byte
+
+// InMemoryObjectStore is a simple implementation of the ObjectStore interface
+// that stores its data in-memory/in-proc. This is mainly intended to be used
+// as a test fake.
+type InMemoryObjectStore struct {
+	Data map[string]BucketData
+}
+
+func NewInMemoryObjectStore(buckets ...string) *InMemoryObjectStore {
+	o := &InMemoryObjectStore{
+		Data: make(map[string]BucketData),
+	}
+
+	for _, bucket := range buckets {
+		o.Data[bucket] = make(map[string][]byte)
+	}
+
+	return o
+}
+
+//
+// Interface Implementation
+//
+
+func (o *InMemoryObjectStore) Init(config map[string]string) error {
+	return nil
+}
+
+func (o *InMemoryObjectStore) PutObject(bucket, key string, body io.Reader) error {
+	bucketData, ok := o.Data[bucket]
+	if !ok {
+		return errors.New("bucket not found")
+	}
+
+	obj, err := ioutil.ReadAll(body)
+	if err != nil {
+		return err
+	}
+
+	bucketData[key] = obj
+
+	return nil
+}
+
+func (o *InMemoryObjectStore) GetObject(bucket, key string) (io.ReadCloser, error) {
+	bucketData, ok := o.Data[bucket]
+	if !ok {
+		return nil, errors.New("bucket not found")
+	}
+
+	obj, ok := bucketData[key]
+	if !ok {
+		return nil, errors.New("key not found")
+	}
+
+	return ioutil.NopCloser(bytes.NewReader(obj)), nil
+}
+
+func (o *InMemoryObjectStore) ListCommonPrefixes(bucket, prefix, delimiter string) ([]string, error) {
+	keys, err := o.ListObjects(bucket, prefix)
+	if err != nil {
+		return nil, err
+	}
+
+	// For each key, check if it has an instance of the delimiter *after* the prefix.
+	// If not, skip it; if so, return the prefix of the key up to/including the delimiter.
+
+	var prefixes []string
+	for _, key := range keys {
+		// everything after 'prefix'
+		afterPrefix := key[len(prefix):]
+
+		// index of the *start* of 'delimiter' in 'afterPrefix'
+		delimiterStart := strings.Index(afterPrefix, delimiter)
+		if delimiterStart == -1 {
+			continue
+		}
+
+		// return the prefix, plus everything after the prefix and before
+		// the delimiter, plus the delimiter
+		fullPrefix := prefix + afterPrefix[0:delimiterStart] + delimiter
+
+		prefixes = append(prefixes, fullPrefix)
+	}
+
+	return prefixes, nil
+}
+
+func (o *InMemoryObjectStore) ListObjects(bucket, prefix string) ([]string, error) {
+	bucketData, ok := o.Data[bucket]
+	if !ok {
+		return nil, errors.New("bucket not found")
+	}
+
+	var objs []string
+	for key := range bucketData {
+		if strings.HasPrefix(key, prefix) {
+			objs = append(objs, key)
+		}
+	}
+
+	return objs, nil
+}
+
+func (o *InMemoryObjectStore) DeleteObject(bucket, key string) error {
+	bucketData, ok := o.Data[bucket]
+	if !ok {
+		return errors.New("bucket not found")
+	}
+
+	delete(bucketData, key)
+
+	return nil
+}
+
+func (o *InMemoryObjectStore) CreateSignedURL(bucket, key string, ttl time.Duration) (string, error) {
+	bucketData, ok := o.Data[bucket]
+	if !ok {
+		return "", errors.New("bucket not found")
+	}
+
+	_, ok = bucketData[key]
+	if !ok {
+		return "", errors.New("key not found")
+	}
+
+	return "a-url", nil
+}
+
+//
+// Test Helper Methods
+//
+
+func (o *InMemoryObjectStore) ClearBucket(bucket string) {
+	if _, ok := o.Data[bucket]; !ok {
+		return
+	}
+
+	o.Data[bucket] = make(map[string][]byte)
+}