Added FileInfo for work with file in OpenAI

But, the problem is that files are created only when purpose =
"fine-tune". When downloading files, the message "To help mitigate
abuse, downloading of fine-tune training files is disabled for free
accounts"

Author: YaroslavVorobyov

ManagedCode.OpenAI.Client.Files/FileDeleteResult.cs

@@ -0,0 +1,12 @@
+using Newtonsoft.Json;
+
+namespace ManagedCode.OpenAI.Client.Files;
+
+public class FileDeleteResult
+{
+    [JsonProperty("id")] public string Id;
+
+    [JsonProperty("object")] public string Object;
+
+    [JsonProperty("deleted")] public bool Deleted;
+}

ManagedCode.OpenAI.Client.Files/FileInfo.cs

@@ -0,0 +1,24 @@
+using Newtonsoft.Json;
+
+namespace ManagedCode.OpenAI.Client.Files;
+
+public class FileInfo
+{
+    [JsonProperty("id")]
+    public string Id;
+
+    [JsonProperty("object")]
+    public string Object;
+
+    [JsonProperty("bytes")]
+    public int Bytes;
+
+    [JsonProperty("created_at")]
+    public int CreatedAt;
+
+    [JsonProperty("filename")]
+    public string Filename;
+
+    [JsonProperty("purpose")]
+    public string Purpose;
+}

ManagedCode.OpenAI.Client.Files/FileListResult.cs

@@ -0,0 +1,12 @@
+using Newtonsoft.Json;
+
+namespace ManagedCode.OpenAI.Client.Files;
+
+public class FileListResult
+{
+    [JsonProperty("data")]
+    public List<FileInfo> Data;
+
+    [JsonProperty("object")]
+    public string Object;
+}

ManagedCode.OpenAI.Client.Files/FileManager.cs

@@ -1,6 +1,127 @@
+using System.Net.Http.Headers;
+using System.Text;
+using ManagedCode.OpenAI.Client.Exceptions;
+using Newtonsoft.Json;
+
 namespace ManagedCode.OpenAI.Client.Files;
 
 public class FileManager
 {
+    public const string URL_FILES = "https://api.openai.com/v1/files";
+
+    public const string URL_FILE = URL_FILES + "/{0}";
+
+    public const string URL_FILE_CONTEXT = URL_FILE + "/content";
+    
+    public const string FINE_TUNE = "fine-tune";
+
+    private readonly OpenAIClient _client;
+
+    internal FileManager(OpenAIClient client)
+    {
+        _client = client;
+    }
+
+    public async Task<FileListResult> ListAsync()
+    {
+        var httpResponseMessage = await _client.GetAsync(URL_FILES);
+
+        OpenAIExceptions.ThrowsIfError(httpResponseMessage.StatusCode);
+
+        string responseBody = await httpResponseMessage.Content.ReadAsStringAsync();
+
+        var result = JsonConvert.DeserializeObject<FileListResult>(responseBody);
+
+        return result;
+    }
+
+    // TODO: Upload file
+
+    public async Task<FileInfo> UploadAsync(string fileName, HttpContent content)
+    {
+        MultipartFormDataContent multipartFormDataContent = new();
+        
+        multipartFormDataContent.Add(new StringContent(FINE_TUNE), "purpose");
+        
+        multipartFormDataContent.Add(content, "file", fileName);
+        
+        var httpResponseMessage = await _client.PostAsync(URL_FILES, multipartFormDataContent);
+
+        OpenAIExceptions.ThrowsIfError(httpResponseMessage.StatusCode);
+
+        string responseBody = await httpResponseMessage.Content.ReadAsStringAsync();
+
+        var result = JsonConvert.DeserializeObject<FileInfo>(responseBody);
+
+
+        return result;
+    }
+
+
+    public async Task<FileInfo> UploadAsync(string fileName, string content)
+    {
+        return await UploadAsync(fileName, new StringContent(content, Encoding.UTF8, "multipart/form-data"));
+    }
 
+    public async Task<FileInfo> UploadAsync(string fileName, Stream content)
+    {
+        return await UploadAsync(fileName, new StreamContent(content));
+    }
+
+    public async Task<FileDeleteResult> DeleteAsync(FileInfo file)
+    {
+        return await DeleteAsync(file.Id);
+    }
+
+    public async Task<FileDeleteResult> DeleteAsync(string fileId)
+    {
+        string resultUrl = string.Format(URL_FILE, fileId);
+
+        var httpResponseMessage = await _client.DeleteAsync(resultUrl);
+
+        OpenAIExceptions.ThrowsIfError(httpResponseMessage.StatusCode);
+
+        string responseBody = await httpResponseMessage.Content.ReadAsStringAsync();
+
+        var result = JsonConvert.DeserializeObject<FileDeleteResult>(responseBody);
+
+        return result;
+    }
+
+    public async Task<FileInfo> RetrieveAsync(FileInfo file)
+    {
+        return await RetrieveAsync(file.Id);
+    }
+
+    public async Task<FileInfo> RetrieveAsync(string fileId)
+    {
+        string resultUrl = string.Format(URL_FILE, fileId);
+
+        var httpResponseMessage = await _client.GetAsync(resultUrl);
+
+        OpenAIExceptions.ThrowsIfError(httpResponseMessage.StatusCode);
+
+        string responseBody = await httpResponseMessage.Content.ReadAsStringAsync();
+
+        var result = JsonConvert.DeserializeObject<FileInfo>(responseBody);
+
+        return result;
+    }
+
+
+    public async Task<Stream> ContentAsync(FileInfo info)
+    {
+        return await ContentAsync(info.Id);
+    }
+
+    public async Task<Stream> ContentAsync(string fileId)
+    {
+        string resultUrl = string.Format(URL_FILE_CONTEXT, fileId);
+
+        var httpResponseMessage = await _client.GetAsync(resultUrl);
+
+        OpenAIExceptions.ThrowsIfError(httpResponseMessage.StatusCode);
+
+        return await httpResponseMessage.Content.ReadAsStreamAsync();
+    }
 }

ManagedCode.OpenAI.Client.Files/FileManagerMethods.cs

@@ -0,0 +1,10 @@
+namespace ManagedCode.OpenAI.Client.Files;
+
+public static class FileManagerMethods
+{
+    
+    public static FileManager AsFileManager(this OpenAIClient client)
+    {
+        return new FileManager(client);
+    }
+}

ManagedCode.OpenAI.Client.Files/ManagedCode.OpenAI.Client.Files.csproj

@@ -6,4 +6,13 @@
         <Nullable>enable</Nullable>
     </PropertyGroup>
 
+    <ItemGroup>
+      <PackageReference Include="Newtonsoft.Json" Version="13.0.3" />
+    </ItemGroup>
+
+    <ItemGroup>
+      <ProjectReference Include="..\ManagedCode.OpenAI.Client.Exceptions\ManagedCode.OpenAI.Client.Exceptions.csproj" />
+      <ProjectReference Include="..\ManagedCode.OpenAI.Client\ManagedCode.OpenAI.Client.csproj" />
+    </ItemGroup>
+
 </Project>