Add a storage backend for Storj

The url format is storj://satellite/bucket/path.  You can get the
satellite along with the api access key when requesting an Access
Grant of type API Access.

src/duplicacy_storage.go

@@ -714,6 +714,23 @@ func CreateStorage(preference Preference, resetPassword bool, threads int) (stor
 		}
 		SavePassword(preference, "fabric_token", token)
 		return smeStorage
+	} else if matched[1] == "storj" {
+		satellite := matched[2] + matched[3]
+		bucket := matched[5]
+		storageDir := ""
+		index := strings.Index(bucket, "/")
+		if index >= 0 {
+			storageDir = bucket[index + 1:]
+			bucket = bucket[:index]
+		}
+		apiKey := GetPassword(preference, "storj_key", "Enter the API access key:", true, resetPassword)
+		passphrase := GetPassword(preference, "storj_passphrase", "Enter the passphrase:", true, resetPassword)
+		storjStorage, err := CreateStorjStorage(satellite, apiKey, passphrase, bucket, storageDir, threads)
+		if err != nil {
+			LOG_ERROR("STORAGE_CREATE", "Failed to load the Storj storage at %s: %v", storageURL, err)
+			return nil
+		}
+		return storjStorage
 	} else {
 		LOG_ERROR("STORAGE_CREATE", "The storage type '%s' is not supported", matched[1])
 		return nil

src/duplicacy_storage_test.go

@@ -169,6 +169,13 @@ func loadStorage(localStoragePath string, threads int) (Storage, error) {
 		}
 		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
 		return storage, err
+	} else if *testStorageName == "storj" {
+		storage, err := CreateStorjStorage(config["satellite"], config["key"], config["passphrase"], config["bucket"], config["storage_path"], threads)
+		if err != nil {
+			return nil, err
+		}
+		storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+		return storage, err
 	}
 
 	return nil, fmt.Errorf("Invalid storage named: %s", *testStorageName)

src/duplicacy_storjstorage.go

@@ -0,0 +1,184 @@
+// Copyright (c) Acrosync LLC. All rights reserved.
+// Free for personal use and commercial trial
+// Commercial use requires per-user licenses available from https://duplicacy.com
+
+package duplicacy
+
+import (
+    "fmt"
+    "io"
+    "context"
+
+    "storj.io/uplink"
+)
+
+// StorjStorage is a storage backend for Storj.
+type StorjStorage struct {
+    StorageBase
+
+    project         *uplink.Project
+    bucket          string
+    storageDir      string
+    numberOfThreads int
+}
+
+// CreateStorjStorage creates a Storj storage.
+func CreateStorjStorage(satellite string, apiKey string, passphrase string,
+                        bucket string, storageDir string, threads int) (storage *StorjStorage, err error) {
+
+    ctx := context.Background()
+    access, err := uplink.RequestAccessWithPassphrase(ctx, satellite, apiKey, passphrase)
+    if err != nil {
+        return nil, fmt.Errorf("cannot request the access grant: %v", err)
+    }
+
+    project, err := uplink.OpenProject(ctx, access)
+    if err != nil {
+        return nil, fmt.Errorf("cannot open the project: %v", err)
+    }
+
+    _, err = project.StatBucket(ctx, bucket)
+    if err != nil {
+        return nil, fmt.Errorf("cannot found the bucket: %v", err)
+    }
+
+    if storageDir != "" && storageDir[len(storageDir) - 1] != '/' {
+        storageDir += "/"
+    }
+
+    storage = &StorjStorage {
+        project: project,
+        bucket: bucket,
+        storageDir: storageDir,
+        numberOfThreads: threads,
+    }
+
+    storage.DerivedStorage = storage
+    storage.SetDefaultNestingLevels([]int{2, 3}, 2)
+    return storage, nil
+}
+
+// ListFiles return the list of files and subdirectories under 'dir' (non-recursively).
+func (storage *StorjStorage) ListFiles(threadIndex int, dir string) (
+                                         files []string, sizes []int64, err error) {
+
+    fullPath := storage.storageDir + dir
+    if fullPath != "" && fullPath[len(fullPath) - 1] != '/' {
+        fullPath += "/"
+    }
+
+    options := uplink.ListObjectsOptions {
+        Prefix: fullPath,
+        System: true, // request SystemMetadata which includes ContentLength 
+    }
+    objects := storage.project.ListObjects(context.Background(), storage.bucket, &options)
+    for objects.Next() {
+        if objects.Err() != nil {
+            return nil, nil, objects.Err()
+        }
+        item := objects.Item()
+        name := item.Key[len(fullPath):]
+        size := item.System.ContentLength
+        if item.IsPrefix {
+            if name != "" && name[len(name) - 1] != '/' {
+                name += "/"
+                size = 0
+            }
+        }
+        files = append(files, name)
+        sizes = append(sizes, size)
+    }
+
+    return files, sizes, nil
+}
+
+// DeleteFile deletes the file or directory at 'filePath'.
+func (storage *StorjStorage) DeleteFile(threadIndex int, filePath string) (err error) {
+
+    _, err = storage.project.DeleteObject(context.Background(), storage.bucket,
+                                          storage.storageDir + filePath)
+    return err
+}
+
+// MoveFile renames the file.
+func (storage *StorjStorage) MoveFile(threadIndex int, from string, to string) (err error) {
+    err = storage.project.MoveObject(context.Background(), storage.bucket,
+                                     storage.storageDir + from, storage.bucket, storage.storageDir + to, nil)
+
+    return err
+}
+
+// CreateDirectory creates a new directory.
+func (storage *StorjStorage) CreateDirectory(threadIndex int, dir string) (err error) {
+    return nil
+}
+
+// GetFileInfo returns the information about the file or directory at 'filePath'.
+func (storage *StorjStorage) GetFileInfo(threadIndex int, filePath string) (
+                                         exist bool, isDir bool, size int64, err error) {
+    info, err := storage.project.StatObject(context.Background(), storage.bucket,
+                                            storage.storageDir + filePath)
+
+    if info == nil {
+        return false, false, 0, nil
+    } else if err != nil {
+        return false, false, 0, err
+    } else {
+        return true, info.IsPrefix, info.System.ContentLength, nil
+    }
+}
+
+// DownloadFile reads the file at 'filePath' into the chunk.
+func (storage *StorjStorage) DownloadFile(threadIndex int, filePath string, chunk *Chunk) (err error) {
+    file, err := storage.project.DownloadObject(context.Background(), storage.bucket,
+                                                storage.storageDir + filePath, nil)
+    if err != nil {
+        return err
+    }
+    defer file.Close()
+    
+    if _, err = RateLimitedCopy(chunk, file, storage.DownloadRateLimit/storage.numberOfThreads); err != nil {
+        return err
+    }
+
+    return nil    
+}
+
+// UploadFile writes 'content' to the file at 'filePath'
+func (storage *StorjStorage) UploadFile(threadIndex int, filePath string, content []byte) (err error) {
+
+    file, err := storage.project.UploadObject(context.Background(), storage.bucket,
+                                              storage.storageDir + filePath, nil)
+    if err != nil {
+        return err
+    }
+                                
+    reader := CreateRateLimitedReader(content, storage.UploadRateLimit/storage.numberOfThreads)
+    _, err = io.Copy(file, reader)
+    if err != nil {
+        return err
+    }
+
+    err = file.Commit()
+    if err != nil {
+        return err
+    }
+
+    return nil
+}
+
+// If a local snapshot cache is needed for the storage to avoid downloading/uploading chunks too often when
+// managing snapshots.
+func (storage *StorjStorage) IsCacheNeeded() bool { return true }
+
+// If the 'MoveFile' method is implemented.
+func (storage *StorjStorage) IsMoveFileImplemented() bool { return true }
+
+// If the storage can guarantee strong consistency.
+func (storage *StorjStorage) IsStrongConsistent() bool { return false }
+
+// If the storage supports fast listing of files names.
+func (storage *StorjStorage) IsFastListing() bool { return true }
+
+// Enable the test mode.
+func (storage *StorjStorage) EnableTestMode() {}