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README.md

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-# storage
-(IN PROGRESS) Go library providing common interface for working with multiple storage backends, including Amazon S3, Google Cloud Storage, Microsoft Azure Blob Storage, Alibaba Cloud OSS Storage, Openstack Object Storage, and Oracle Cloud Infrastructure Object Storage
+# chartmuseum/storage
+
+Go library providing a common interface for working across multiple storage backends.
+
+Supported storage backends:
+
+- Local filesystem
+- [Amazon S3](https://aws.amazon.com/s3/)
+- [Google Cloud Storage](https://cloud.google.com/storage/)
+- [Microsoft Azure Blob Storage](https://azure.microsoft.com/en-us/services/storage/blobs/)
+- [Alibaba Cloud OSS Storage](https://www.alibabacloud.com/product/oss)
+- [Openstack Object Storage](https://developer.openstack.org/api-ref/object-store/)
+- [Oracle Cloud Infrastructure Object Storage](https://cloud.oracle.com/storage)
+
+## Primary Components
+
+### Backend (interface)
+
+`Backend` is a common interface that is implemented by all the supported storage backends and their associated types:
+
+```go
+Backend interface {
+    ListObjects(prefix string) ([]Object, error)
+    GetObject(path string) (Object, error)
+    PutObject(path string, content []byte) error
+    DeleteObject(path string) error
+}
+```
+
+### Object (struct)
+
+`Object` is a struct that represents a single storage object:
+
+```go
+Object struct {
+    Path         string
+    Content      []byte
+    LastModified time.Time
+}
+```
+
+## Usage
+
+### Simple example
+
+The following is a simple program that will upload a file either to an Azure Blob Storage bucket (container) or a Google Cloud Storage bucket based on the command line options provided:
+```go
+// Usage: go run example.go <cloud> <bucket> <file>
+
+package main
+
+import (
+	"fmt"
+	"github.com/chartmuseum/storage"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+type (
+	Uploader struct {
+		Backend storage.Backend
+	}
+)
+
+func NewUploader(cloud string, bucket string) *Uploader {
+	var backend storage.Backend
+	switch cloud {
+	case "azure":
+		backend = storage.Backend(storage.NewMicrosoftBlobBackend(bucket, ""))
+	case "google":
+		backend = storage.Backend(storage.NewGoogleCSBackend(bucket, ""))
+	default:
+		panic("cloud provider " + cloud + " not supported")
+	}
+	uploader := Uploader{Backend: backend}
+	fmt.Printf("uploader created (cloud: %s, bucket: %s)\n", cloud, bucket)
+	return &uploader
+}
+
+func (uploader *Uploader) Upload(filename string) {
+	basename := filepath.Base(filename)
+	content, err := ioutil.ReadFile(filename)
+	if err != nil {
+		panic(err)
+	}
+	err = uploader.Backend.PutObject(basename, content)
+	if err != nil {
+		panic(err)
+	}
+	fmt.Printf("%s successfully uploaded\n", basename)
+}
+
+func main() {
+	args := os.Args[1:]
+	uploader := NewUploader(args[0], args[1])
+	uploader.Upload(args[2])
+}
+
+```
+
+Example of using to upload the file `index.html` to an Azure bucket:
+
+```
+go run example.go azure mycontainer index.html
+```
+
+Example of using to upload the file `index.html` to a Google Cloud bucket:
+
+```
+go run example.go google mybucket index.html
+```
+
+### Per backend
+
+TODO