Implemented File Upload Client. (#6358)

Author: michaelstaib

src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReference.cs

@@ -0,0 +1,88 @@
+using System;
+using System.IO;
+using static HotChocolate.Transport.Properties.TransportAbstractionResoucrces;
+
+namespace HotChocolate.Transport.Http;
+
+/// <summary>
+/// A file reference can be used to upload a file with the
+/// GraphQL multipart request protocol.
+/// </summary>
+public sealed class FileReference
+{
+    private readonly Func<Stream> _openRead;
+
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReference" />
+    /// </summary>
+    /// <param name="stream">
+    /// The file stream.
+    /// </param>
+    /// <param name="fileName">
+    /// The file name.
+    /// </param>
+    /// <exception cref="ArgumentNullException">
+    /// <paramref name="stream"/> is <c>null</c>.
+    /// </exception>
+    /// <exception cref="ArgumentException">
+    /// <paramref name="fileName"/> is <c>null</c>, empty or white space.
+    /// </exception>
+    public FileReference(Stream stream, string fileName)
+    {
+        if (stream == null)
+        {
+            throw new ArgumentNullException(nameof(stream));
+        }
+
+        if (string.IsNullOrWhiteSpace(fileName))
+        {
+            throw new ArgumentException(
+                FileReference_FileName_NullOrEmpty, 
+                nameof(fileName));
+        }
+        
+        _openRead = () => stream;
+        FileName = fileName;
+    }
+    
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReference" />
+    /// </summary>
+    /// <param name="openRead">
+    /// The stream factory.
+    /// </param>
+    /// <param name="fileName">
+    /// The file name.
+    /// </param>
+    /// <exception cref="ArgumentException">
+    /// <paramref name="fileName"/> is <c>null</c>, empty or white space.
+    /// </exception>
+    /// <exception cref="ArgumentNullException">
+    /// <paramref name="openRead"/> is <c>null</c>.
+    /// </exception>
+    public FileReference(Func<Stream> openRead, string fileName)
+    {
+        if (string.IsNullOrWhiteSpace(fileName))
+        {
+            throw new ArgumentException(
+                FileReference_FileName_NullOrEmpty, 
+                nameof(fileName));
+        }
+        
+        _openRead = openRead ?? throw new ArgumentNullException(nameof(openRead));
+        FileName = fileName;
+    }
+
+    /// <summary>
+    /// The file name eg. <c>foo.txt</c>.
+    /// </summary>
+    public string FileName { get; }
+    
+    /// <summary>
+    /// Opens the file stream.
+    /// </summary>
+    /// <returns>
+    /// Returns the file stream.
+    /// </returns>
+    public Stream OpenRead() => _openRead();
+}

src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReferenceInfo.cs

@@ -0,0 +1,35 @@
+namespace HotChocolate.Transport.Http;
+
+/// <summary>
+/// The file reference info contains the actual
+/// <see cref="FileReference"/> and the reference
+/// name that is used to upload the referenced file.
+/// </summary>
+public sealed class FileReferenceInfo
+{
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReferenceInfo" />
+    /// </summary>
+    /// <param name="file">
+    /// The file reference.
+    /// </param>
+    /// <param name="name">
+    /// The internal reference name.
+    /// </param>
+    internal FileReferenceInfo(FileReference file, string name)
+    {
+        File = file;
+        Name = name;
+    }
+
+    /// <summary>
+    /// Gets the file that shall be uploaded.
+    /// </summary>
+    public FileReference File { get; }
+    
+    /// <summary>
+    /// Gets the internal reference name that is used to refer to
+    /// this file instance within the GraphQL multipart request protocol. 
+    /// </summary>
+    public string Name { get; }
+}

src/HotChocolate/AspNetCore/src/Transport.Abstractions/FileReferenceNode.cs

@@ -0,0 +1,209 @@
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Linq;
+using HotChocolate.Language;
+using HotChocolate.Language.Utilities;
+
+namespace HotChocolate.Transport.Http;
+
+/// <summary>
+/// This file literal is used in order to allow for file references in <see cref="ObjectValueNode"/>.
+/// </summary>
+public sealed class FileReferenceNode
+    : IValueNode<FileReference>
+    , IValueNode<string>
+    , IEquatable<FileReferenceNode>
+{
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReferenceNode" />
+    /// </summary>
+    /// <param name="stream">
+    /// The file stream.
+    /// </param>
+    /// <param name="fileName">
+    /// The file name.
+    /// </param>
+    public FileReferenceNode(Stream stream, string fileName)
+        : this(new FileReference(() => stream, fileName)) { }
+
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReferenceNode" />
+    /// </summary>
+    /// <param name="openRead">
+    /// The stream factory.
+    /// </param>
+    /// <param name="fileName">
+    /// The file name.
+    /// </param>
+    public FileReferenceNode(Func<Stream> openRead, string fileName)
+        : this(new FileReference(openRead, fileName)) { }
+
+    /// <summary>
+    /// Creates a new instance of <see cref="FileReferenceNode" />
+    /// </summary>
+    /// <param name="value">
+    /// The file Reference.
+    /// </param>
+    public FileReferenceNode(FileReference value)
+    {
+        Value = value ?? throw new ArgumentNullException(nameof(value));
+    }
+
+    /// <summary>
+    /// Returns the <see cref="SyntaxKind"/> of the node.
+    /// </summary>
+    public SyntaxKind Kind => SyntaxKind.StringValue;
+
+    /// <summary>
+    /// Gets a <see cref="Location"/> of this node in the parsed source text 
+    /// if available the parser provided this information.
+    /// </summary>
+    public Location? Location => null;
+
+    /// <summary>
+    /// Gets the actual file reference.
+    /// </summary>
+    public FileReference Value { get; }
+
+    object? IValueNode.Value => Value;
+
+    string IValueNode<string>.Value => Value.FileName;
+
+    /// <summary>
+    /// Gets the children of this node.
+    /// </summary>
+    /// <returns>
+    /// Returns the children of this node..
+    /// </returns>
+    public IEnumerable<ISyntaxNode> GetNodes()
+        => Enumerable.Empty<ISyntaxNode>();
+
+    /// <summary>
+    /// Determines whether the specified <see cref="IValueNode"/> is equal
+    /// to the current <see cref="FileReferenceNode"/>.
+    /// </summary>
+    /// <param name="other">
+    /// The <see cref="IValueNode"/> to compare with the current
+    /// <see cref="FileReferenceNode"/>.
+    /// </param>
+    /// <returns>
+    /// <c>true</c> if the specified <see cref="IValueNode"/> is equal
+    /// to the current <see cref="FileReferenceNode"/>;
+    /// otherwise, <c>false</c>.
+    /// </returns>
+    public bool Equals(FileReferenceNode? other)
+    {
+        if (ReferenceEquals(null, other))
+        {
+            return false;
+        }
+
+        if (ReferenceEquals(this, other) ||
+            ReferenceEquals(Value, other.Value))
+        {
+            return true;
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// Determines whether the specified <see cref="IValueNode"/> is equal
+    /// to the current <see cref="FileReferenceNode"/>.
+    /// </summary>
+    /// <param name="other">
+    /// The <see cref="IValueNode"/> to compare with the current
+    /// <see cref="FileReferenceNode"/>.
+    /// </param>
+    /// <returns>
+    /// <c>true</c> if the specified <see cref="IValueNode"/> is equal
+    /// to the current <see cref="FileReferenceNode"/>;
+    /// otherwise, <c>false</c>.
+    /// </returns>
+    public bool Equals(IValueNode? other)
+    {
+        if (ReferenceEquals(null, other))
+        {
+            return false;
+        }
+
+        if (ReferenceEquals(this, other))
+        {
+            return true;
+        }
+
+        if (other is FileReferenceNode file)
+        {
+            return Equals(file);
+        }
+
+        return false;
+    }
+
+    /// <summary>
+    /// Determines whether the specified <see cref="object"/> is equal to
+    /// the current <see cref="FileReferenceNode"/>.
+    /// </summary>
+    /// <param name="obj">
+    /// The <see cref="object"/> to compare with the current
+    /// <see cref="FileReferenceNode"/>.
+    /// </param>
+    /// <returns>
+    /// <c>true</c> if the specified <see cref="object"/> is equal to the
+    /// current <see cref="FileReferenceNode"/>; otherwise, <c>false</c>.
+    /// </returns>
+    public override bool Equals(object? obj)
+    {
+        if (ReferenceEquals(null, obj))
+        {
+            return false;
+        }
+
+        if (ReferenceEquals(obj, this))
+        {
+            return true;
+        }
+
+        return Equals(obj as FileReferenceNode);
+    }
+
+    /// <summary>
+    /// Serves as a hash function for a <see cref="FileReferenceNode"/>
+    /// object.
+    /// </summary>
+    /// <returns>
+    /// A hash code for this instance that is suitable for use in
+    /// hashing algorithms and data structures such as a hash table.
+    /// </returns>
+    public override int GetHashCode()
+    {
+        unchecked
+        {
+            return (Kind.GetHashCode() * 397) ^ (Value.GetHashCode() * 97);
+        }
+    }
+
+    /// <summary>
+    /// Returns the GraphQL syntax representation of this <see cref="ISyntaxNode"/>.
+    /// </summary>
+    /// <returns>
+    /// Returns the GraphQL syntax representation of this <see cref="ISyntaxNode"/>.
+    /// </returns>
+    public override string ToString()
+        => ToString(true);
+
+    /// <summary>
+    /// Returns the GraphQL syntax representation of this <see cref="ISyntaxNode"/>.
+    /// </summary>
+    /// <param name="indented">
+    /// A value that indicates whether the GraphQL output should be formatted,
+    /// which includes indenting nested GraphQL tokens, adding
+    /// new lines, and adding white space between property names and values.
+    /// </param>
+    /// <returns>
+    /// Returns the GraphQL syntax representation of this <see cref="ISyntaxNode"/>.
+    /// </returns>
+    public string ToString(bool indented)
+        => SyntaxPrinter.Print(this, indented);
+}

src/HotChocolate/AspNetCore/src/Transport.Abstractions/Properties/TransportAbstractionResoucrces.Designer.cs

@@ -24,4 +24,7 @@
   <data name="OperationResult_Parse_JsonDataIsEmpty" xml:space="preserve">
     <value>The JSON document is empty.</value>
   </data>
+  <data name="FileReference_FileName_NullOrEmpty" xml:space="preserve">
+    <value>Value cannot be null or whitespace.</value>
+  </data>
 </root>