Add FileSystemFileProvider to expose an IFileSystem as IFileProvider

Author: ronaldbarendse

src/Umbraco.Core/IO/FileSystemDirectoryContents.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections;
+using System.Collections.Generic;
+using System.Linq;
+using Microsoft.Extensions.FileProviders;
+
+namespace Umbraco.Cms.Core.IO
+{
+    /// <summary>
+    /// Represents the directory contents in an <see cref="IFileSystem" />.
+    /// </summary>
+    /// <seealso cref="Microsoft.Extensions.FileProviders.IDirectoryContents" />
+    public class FileSystemDirectoryContents : IDirectoryContents
+    {
+        private readonly IFileSystem _fileSystem;
+        private readonly string _subpath;
+        private IEnumerable<IFileInfo> _entries = null!;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FileSystemDirectoryContents"/> class.
+        /// </summary>
+        /// <param name="fileSystem">The file system.</param>
+        /// <param name="subpath">The subpath.</param>
+        /// <exception cref="System.ArgumentNullException">
+        /// fileSystem
+        /// or
+        /// subpath
+        /// </exception>
+        public FileSystemDirectoryContents(IFileSystem fileSystem, string subpath)
+        {
+            _fileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
+            _subpath = subpath ?? throw new ArgumentNullException(nameof(subpath));
+        }
+
+        /// <inheritdoc />
+        public bool Exists => true;
+
+        /// <inheritdoc />
+        public IEnumerator<IFileInfo> GetEnumerator()
+        {
+            EnsureInitialized();
+            return _entries.GetEnumerator();
+        }
+
+        /// <inheritdoc />
+        IEnumerator IEnumerable.GetEnumerator()
+        {
+            EnsureInitialized();
+            return _entries.GetEnumerator();
+        }
+
+        private void EnsureInitialized()
+        {
+            _entries = _fileSystem.GetDirectories(_subpath).Select<string, IFileInfo>(d => new FileSystemDirectoryInfo(_fileSystem, d))
+                .Union(_fileSystem.GetFiles(_subpath).Select<string, IFileInfo>(f => new FileSystemFileInfo(_fileSystem, f)))
+                .ToList();
+        }
+    }
+}

src/Umbraco.Core/IO/FileSystemDirectoryInfo.cs

@@ -0,0 +1,48 @@
+using System;
+using System.IO;
+using Microsoft.Extensions.FileProviders;
+
+namespace Umbraco.Cms.Core.IO
+{
+    /// <summary>
+    /// Represents a directory in an <see cref="IFileSystem" />.
+    /// </summary>
+    /// <seealso cref="Microsoft.Extensions.FileProviders.IFileInfo" />
+    public class FileSystemDirectoryInfo : IFileInfo
+    {
+        private readonly IFileSystem _fileSystem;
+        private readonly string _subpath;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FileSystemDirectoryInfo" /> class.
+        /// </summary>
+        /// <param name="fileSystem">The file system.</param>
+        /// <param name="subpath">The subpath.</param>
+        public FileSystemDirectoryInfo(IFileSystem fileSystem, string subpath)
+        {
+            _fileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
+            _subpath = subpath ?? throw new ArgumentNullException(nameof(subpath));
+        }
+
+        /// <inheritdoc />
+        public bool Exists => true;
+
+        /// <inheritdoc />
+        public bool IsDirectory => true;
+
+        /// <inheritdoc />
+        public DateTimeOffset LastModified => _fileSystem.GetLastModified(_subpath);
+
+        /// <inheritdoc />
+        public long Length => -1;
+
+        /// <inheritdoc />
+        public string Name => _fileSystem.GetRelativePath(_subpath);
+
+        /// <inheritdoc />
+        public string PhysicalPath => null!;
+
+        /// <inheritdoc />
+        public Stream CreateReadStream() => throw new InvalidOperationException("Cannot create a stream for a directory.");
+    }
+}

src/Umbraco.Core/IO/FileSystemFileInfo.cs

@@ -0,0 +1,48 @@
+using System;
+using System.IO;
+using Microsoft.Extensions.FileProviders;
+
+namespace Umbraco.Cms.Core.IO
+{
+    /// <summary>
+    /// Represents a file in an <see cref="IFileSystem" />.
+    /// </summary>
+    /// <seealso cref="Microsoft.Extensions.FileProviders.IFileInfo" />
+    public class FileSystemFileInfo : IFileInfo
+    {
+        private readonly IFileSystem _fileSystem;
+        private readonly string _subpath;
+
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FileSystemFileInfo" /> class.
+        /// </summary>
+        /// <param name="fileSystem">The file system.</param>
+        /// <param name="subpath">The subpath.</param>
+        public FileSystemFileInfo(IFileSystem fileSystem, string subpath)
+        {
+            _fileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
+            _subpath = subpath ?? throw new ArgumentNullException(nameof(subpath));
+        }
+
+        /// <inheritdoc />
+        public bool Exists => true;
+
+        /// <inheritdoc />
+        public bool IsDirectory => false;
+
+        /// <inheritdoc />
+        public DateTimeOffset LastModified => _fileSystem.GetLastModified(_subpath);
+
+        /// <inheritdoc />
+        public long Length => _fileSystem.GetSize(_subpath);
+
+        /// <inheritdoc />
+        public string Name => _fileSystem.GetRelativePath(_subpath);
+
+        /// <inheritdoc />
+        public string PhysicalPath => null!;
+
+        /// <inheritdoc />
+        public Stream CreateReadStream() => _fileSystem.OpenFile(_subpath);
+    }
+}

src/Umbraco.Core/IO/FileSystemFileProvider.cs

@@ -0,0 +1,62 @@
+using System;
+using Microsoft.Extensions.FileProviders;
+using Microsoft.Extensions.Primitives;
+
+namespace Umbraco.Cms.Core.IO
+{
+    /// <summary>
+    /// Exposes an <see cref="IFileSystem" /> as an <see cref="IFileProvider" />.
+    /// </summary>
+    /// <seealso cref="Microsoft.Extensions.FileProviders.IFileProvider" />
+    public class FileSystemFileProvider : IFileProvider
+    {
+        /// <summary>
+        /// Initializes a new instance of the <see cref="FileSystemFileProvider" /> class.
+        /// </summary>
+        /// <param name="fileSystem">The file system.</param>
+        /// <param name="pathPrefix">The path prefix.</param>
+        /// <exception cref="System.ArgumentNullException">fileSystem</exception>
+        public FileSystemFileProvider(IFileSystem fileSystem, string pathPrefix = null)
+        {
+            FileSystem = fileSystem ?? throw new ArgumentNullException(nameof(fileSystem));
+            PathPrefix = pathPrefix;
+        }
+
+        /// <summary>
+        /// Gets the file system.
+        /// </summary>
+        protected IFileSystem FileSystem { get; }
+
+        /// <summary>
+        /// Gets the path prefix.
+        /// </summary>
+        protected string PathPrefix { get; }
+
+        /// <inheritdoc />
+        public IDirectoryContents GetDirectoryContents(string subpath)
+        {
+            var path = PathPrefix + subpath;
+            if (path == null || !FileSystem.DirectoryExists(path))
+            {
+                return NotFoundDirectoryContents.Singleton;
+            }
+
+            return new FileSystemDirectoryContents(FileSystem, path);
+        }
+
+        /// <inheritdoc />
+        public IFileInfo GetFileInfo(string subpath)
+        {
+            var path = PathPrefix + subpath;
+            if (path == null || !FileSystem.FileExists(path))
+            {
+                return new NotFoundFileInfo(path);
+            }
+
+            return new FileSystemFileInfo(FileSystem, path);
+        }
+
+        /// <inheritdoc />
+        public IChangeToken Watch(string filter) => NullChangeToken.Singleton;
+    }
+}