Cloud.File.Storage.Manager.AzureBlob 4.0.0

Cloud File Storage Manager

Provides complete implementation to handle easily cloud file storage operations like get informations about files, reading, downloadURL generation, file update, file move and delete. Primarily for Azure (Azure Blob Storage) right now.

Configuration

Let's add a section to the appsettings.json

"AzureStorageSettings": {
    // Optional - http or https, defaults to https when empty
    "Protocol": "https",
    "AccountName": "",
    "AccountKey": "",
    "ContainerName": "",
    // Optional - Leave empty to use the azure default url (<AccountName>.blob.core.windows.net), see the Url rules below
    "Url": ""
}

In the application, configure this settings part

services.AddSingleton<ICloudFileStorageManager, AzureCloudFileStorageManager>(services => new AzureCloudFileStorageManager(new AzureCloudFileStorageManagerOptions()
{
    AccountName = config.GetSection("AzureStorageSettings").GetValue<string>("AccountName"),
    AccountKey = config.GetSection("AzureStorageSettings").GetValue<string>("AccountKey"),
    ContainerName = config.GetSection("AzureStorageSettings").GetValue<string>("ContainerName"),
    Protocol = config.GetSection("AzureStorageSettings").GetValue<string>("Protocol"),
    Url = config.GetSection("AzureStorageSettings").GetValue<string>("Url")
}));  

Endpoint (Url and Protocol)

• Protocol is http or https (case-insensitive). When empty it defaults to https; any other value is refused with an ArgumentException.
• Url is the blob endpoint as host[:port], for example myaccount.blob.core.windows.net or blob.example.com:8443.
• Url may start with http:// or https://; the scheme then overrides Protocol. Other schemes are refused.
• Url may carry at most one path segment, the account name of a path-style endpoint such as Azurite: 127.0.0.1:10000/devstoreaccount1.
• A query string (?), a fragment (#), user info (@), a backslash or more than one path segment is refused with an ArgumentException.

Download links

GetDownloadUrl / GetDownloadUrlAsync returns a SAS link signed with the account key:

• the link is read-only,
• the validity is capped at 7 days (a longer requested validity is shortened to 7 days),
• on an https endpoint the link only works over https.

Listings and deletes

• Listings return one level of the folder hierarchy: the files directly in the folder and its sub-folders, with paths relative to the root directory. Folders are reported as existing.
• Reads, listings and deletes never create the container; it is created on the first write. A missing container lists as empty and deletes nothing.
• Deleting a folder removes every blob under it page by page (1000 blobs per page); Delete returns false when nothing was found.
• The root directory (the container itself or the configured RootDirectoryPath) cannot be deleted.
• Files are stored as append blobs. Writes are not atomic: concurrent readers can observe partial content.
• Move copies the blob server-side under a 60 second lease that is renewed while the copy runs, and gives up after 10 minutes.
• Watch is not supported (throws NotSupportedException).

Path rules

Path segments are validated by Cloud.File.Storage.Manager.Common: empty or whitespace segments, segments made only of dots and spaces, control characters and percent-encoded separators are refused with an ArgumentException.