GaEpd.FileService 2.1.0

Georgia EPD-IT File Service Library

This library was created by Georgia EPD-IT to provide common file services for our web applications.

Installation

To install, search for "GaEpd.FileService" in the NuGet package manager or run the following command:

dotnet add package GaEpd.FileService

Usage

An IFileService interface is used to abstract out common file persistence operations:

• SaveFileAsync
• FileExistsAsync
• GetFileAsync
• TryGetFileAsync
• DeleteFileAsync

The library also includes three useful implementations, In Memory, File System, and Azure Blob Storage. Each implementation can be registered independently as shown in the sections below.

Alternatively, the AddFileServices extension method can be used to automatically register an implementation based on the configuration. To do so, register the file services configuration as follows:

builder.Services.AddFileServices(builder.Configuration);

And add the following section to your configuration:

{
  "FileServiceSettings": {
    "FileService": "",
    "FileSystemBasePath": "",
    "NetworkUsername": "",
    "NetworkDomain": "",
    "NetworkPassword": "",
    "AzureAccountName": "",
    "BlobContainer": "",
    "BlobBasePath": ""
  }
}

The FileService setting must be set to "InMemory", "FileSystem", or "AzureBlobStorage".

• If InMemory is chosen, all other settings are ignored.

• If FileSystem is chosen, then FileSystemBasePath is required, and NetworkUsername, NetworkDomain, and NetworkPassword can be provided if needed. Other settings are ignored.

• If AzureBlobStorage is chosen, then AzureAccountName and BlobContainer are required, and BlobBasePath can be provided if desired. Other settings are ignored.

In Memory

The in-memory file service implementation stores files in memory.

builder.Services.AddSingleton<IFileService, InMemoryFileService>();

File System

The file system service writes files to a local or network drive. The basePath parameter is required and defines where the files will be stored.

builder.Services.AddTransient<IFileService, FileSystemFileService>(_ =>
    new FileSystemFileService(basePath));

If a Windows Identity is required to access the desired file location, use the overload that accepts username, domain, and password parameters in the constructor.

builder.Services.AddTransient<IFileService, FileSystemFileService>(_ =>
    new FileSystemFileService(basePath, username, domain, password));

Azure Blob Storage

The Azure Blob Storage service requires an Azure account and an existing Blob Storage container. (The service does not attempt to create the container if it does not exist.) The basePath parameter is optional and is prepended to file names as a path segment. DefaultAzureCredential is used to initialize the BlobServiceClient.

builder.Services.AddSingleton<IFileService, AzureBlobFileService>(_ =>
    new AzureBlobFileService(accountName, container, basePath));

Warning: At the moment, the SaveFileAsync() method throws an exception when using Azure Blob Storage if the file already exists.