UnrealEngineUWP/Engine/Source/Programs/UnrealCloudDDC/Jupiter/Controllers/BlobController.cs

// Copyright Epic Games, Inc. All Rights Reserved.

using System;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Mime;
using System.Threading.Tasks;
using EpicGames.AspNet;
using EpicGames.Horde.Storage;
using EpicGames.Serialization;
using Jupiter.Implementation;
using Jupiter.Common.Implementation;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Mvc;

namespace Jupiter.Controllers
{
	using IDiagnosticContext = Serilog.IDiagnosticContext;
	using BlobNotFoundException = Jupiter.Implementation.BlobNotFoundException;

	[ApiController]
	[Route("api/v1/s", Order = 1)]
	[Route("api/v1/blobs", Order = 0)]
	[Authorize]
	public class BlobsController : ControllerBase
	{
		private readonly IBlobService _storage;
		private readonly IDiagnosticContext _diagnosticContext;
		private readonly IRequestHelper _requestHelper;
		private readonly BufferedPayloadFactory _bufferedPayloadFactory;
		private readonly NginxRedirectHelper _nginxRedirectHelper;

		public BlobsController(IBlobService storage, IDiagnosticContext diagnosticContext, IRequestHelper requestHelper, BufferedPayloadFactory bufferedPayloadFactory, NginxRedirectHelper nginxRedirectHelper)
		{
			_storage = storage;
			_diagnosticContext = diagnosticContext;
			_requestHelper = requestHelper;
			_bufferedPayloadFactory = bufferedPayloadFactory;
			_nginxRedirectHelper = nginxRedirectHelper;
		}

		[HttpGet("{ns}/{id}")]
		[ProducesDefaultResponseType]
		public async Task<IActionResult> GetAsync(
			[Required] NamespaceId ns,
			[Required] BlobId id,
			[FromQuery] List<string>? storageLayers = null)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.ReadObject });
			if (result != null)
			{
				return result;
			}

			try
			{
				BlobContents blobContents = await GetImplAsync(ns, id, storageLayers, supportsRedirectUri: true);

				if (blobContents.RedirectUri != null)
				{
					return Redirect(blobContents.RedirectUri.ToString());
				}
				if (_nginxRedirectHelper.CanRedirect(Request, blobContents))
				{
					return _nginxRedirectHelper.CreateActionResult(blobContents, MediaTypeNames.Application.Octet);
				}
				return File(blobContents.Stream, MediaTypeNames.Application.Octet, enableRangeProcessing: true);
			}
			catch (BlobNotFoundException e)
			{
				return NotFound(new ValidationProblemDetails { Title = $"Blob {e.Blob} not found"});
			}
			catch (AuthorizationException e)
			{
				return e.Result;
			}
		}
		
		[HttpHead("{ns}/{id}")]
		[ProducesDefaultResponseType]
		public async Task<IActionResult> HeadAsync(
			[Required] NamespaceId ns,
			[Required] BlobId id,
			[FromQuery] List<string>? storageLayers = null)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.ReadObject });
			if (result != null)
			{
				return result;
			}
			bool exists = await _storage.ExistsAsync(ns, id, storageLayers);

			if (!exists)
			{
				return NotFound(new ValidationProblemDetails { Title = $"Blob {id} not found"});
			}

			return Ok();
		}

		[HttpPost("{ns}/exists")]
		[ProducesDefaultResponseType]
		public async Task<IActionResult> ExistsMultipleAsync(
			[Required] NamespaceId ns,
			[Required] [FromQuery] List<BlobId> id)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.ReadObject });
			if (result != null)
			{
				return result;
			}

			ConcurrentBag<BlobId> missingBlobs = new ConcurrentBag<BlobId>();

			IEnumerable<Task> tasks = id.Select(async blob =>
			{
				if (!await _storage.ExistsAsync(ns, blob))
				{
					missingBlobs.Add(blob);
				}
			});
			await Task.WhenAll(tasks);

			return Ok(new HeadMultipleResponse { Needs = missingBlobs.ToArray()});
		}

		[HttpPost("{ns}/exist")]
		[ProducesDefaultResponseType]
		public async Task<IActionResult> ExistsBodyAsync(
			[Required] NamespaceId ns,
			[FromBody] BlobId[] bodyIds)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.ReadObject });
			if (result != null)
			{
				return result;
			}

			ConcurrentBag<BlobId> missingBlobs = new ConcurrentBag<BlobId>();

			IEnumerable<Task> tasks = bodyIds.Select(async blob =>
			{
				if (!await _storage.ExistsAsync(ns, blob))
				{
					missingBlobs.Add(blob);
				}
			});
			await Task.WhenAll(tasks);

			return Ok(new HeadMultipleResponse { Needs = missingBlobs.ToArray()});
		}

		private async Task<BlobContents> GetImplAsync(NamespaceId ns, BlobId blob, List<string>? storageLayers = null, bool supportsRedirectUri = false)
		{
			try
			{
				return await _storage.GetObjectAsync(ns, blob, storageLayers, supportsRedirectUri);
			}
			catch (BlobNotFoundException)
			{
				if (!_storage.ShouldFetchBlobOnDemand(ns))
				{
					throw;
				}

				return await _storage.ReplicateObjectAsync(ns, blob);
			}
		}

		[HttpPut("{ns}/{id}")]
		[RequiredContentType(MediaTypeNames.Application.Octet)]
		[DisableRequestSizeLimit]
		public async Task<IActionResult> PutAsync(
			[Required] NamespaceId ns,
			[Required] BlobId id)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.WriteObject });
			if (result != null)
			{
				return result;
			}

			_diagnosticContext.Set("Content-Length", Request.ContentLength ?? -1);

			try
			{
				Uri? uri = await _storage.MaybePutObjectWithRedirectAsync(ns, id);
				if (uri != null)
				{
					return Ok(new
					{
						Identifier = id.ToString(),
						RedirectUri = uri,
					});
				}
				using IBufferedPayload payload = await _bufferedPayloadFactory.CreateFromRequest(Request);

				BlobId identifier = await _storage.PutObjectAsync(ns, payload, id);
				return Ok(new
				{
					Identifier = identifier.ToString()
				});
			}
			catch (ResourceHasToManyRequestsException)
			{
				return StatusCode(StatusCodes.Status429TooManyRequests);
			}
			catch (ClientSendSlowException e)
			{
				return Problem(e.Message, null, (int)HttpStatusCode.RequestTimeout);
			}
		}

		[HttpPost("{ns}")]
		[RequiredContentType(MediaTypeNames.Application.Octet)]
		[DisableRequestSizeLimit]
		public async Task<IActionResult> PostAsync(
			[Required] NamespaceId ns)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.WriteObject });
			if (result != null)
			{
				return result;
			}

			_diagnosticContext.Set("Content-Length", Request.ContentLength ?? -1);
			try
			{
				using IBufferedPayload payload = await _bufferedPayloadFactory.CreateFromRequest(Request);

				await using Stream stream = payload.GetStream();

				BlobId id = await BlobId.FromStreamAsync(stream);
				await _storage.PutObjectKnownHashAsync(ns, payload, id);
				
				return Ok(new
				{
					Identifier = id.ToString()
				});
			}
			catch (ClientSendSlowException e)
			{
				return Problem(e.Message, null, (int)HttpStatusCode.RequestTimeout);
			}
		}

		[HttpDelete("{ns}/{id}")]
		public async Task<IActionResult> DeleteAsync(
			[Required] NamespaceId ns,
			[Required] BlobId id)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.DeleteObject });
			if (result != null)
			{
				return result;
			}

			await DeleteImplAsync(ns, id);

			return NoContent();
		}

		
		[HttpDelete("{ns}")]
		public async Task<IActionResult> DeleteNamespaceAsync(
			[Required] NamespaceId ns)
		{
			ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, ns, new [] { JupiterAclAction.DeleteNamespace });
			if (result != null)
			{
				return result;
			}

			await  _storage.DeleteNamespaceAsync(ns);

			return NoContent();
		}

		private async Task DeleteImplAsync(NamespaceId ns, BlobId id)
		{
			await _storage.DeleteObjectAsync(ns, id);
		}

		// ReSharper disable UnusedAutoPropertyAccessor.Global
		// ReSharper disable once ClassNeverInstantiated.Global
		[System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1034:Nested types should not be visible", Justification = "Used by serialization")]
		public class BatchOp
		{
			// ReSharper disable once InconsistentNaming
			public enum Operation
			{
				INVALID,
				GET,
				PUT,
				DELETE,
				HEAD
			}

			[Required] public NamespaceId? Namespace { get; set; }

			public BlobId? Id { get; set; }

			[Required] public Operation Op { get; set; }

			public byte[]? Content { get; set; }
		}

		[System.Diagnostics.CodeAnalysis.SuppressMessage("Design", "CA1034:Nested types should not be visible", Justification = "Used by serialization")]
		public class BatchCall
		{
			public BatchOp[]? Operations { get; set; }
		}
		// ReSharper restore UnusedAutoPropertyAccessor.Global

		[HttpPost("")]
		public async Task<IActionResult> PostAsync([FromBody] BatchCall batch)
		{
			JupiterAclAction MapToAclAction(BatchOp.Operation op)
			{
				switch (op)
				{
					case BatchOp.Operation.GET:
					case BatchOp.Operation.HEAD:
						return JupiterAclAction.ReadObject;
					case BatchOp.Operation.PUT:
						return JupiterAclAction.WriteObject;
					case BatchOp.Operation.DELETE:
						return JupiterAclAction.DeleteObject;
					default:
						throw new ArgumentOutOfRangeException(nameof(op), op, null);
				}
			}

			if (batch?.Operations == null)
			{
				throw new ();
			}

			Task<object?>[] tasks = new Task<object?>[batch.Operations.Length];
			for (int index = 0; index < batch.Operations.Length; index++)
			{
				BatchOp op = batch.Operations[index];
				if (op.Namespace == null)
				{
					throw new Exception(nameof(op.Namespace));
				}

				ActionResult? result = await _requestHelper.HasAccessToNamespaceAsync(User, Request, op.Namespace!.Value, new[] { MapToAclAction(op.Op) });

				if (result != null)
				{
					return result;
				}

				switch (op.Op)
				{
					case BatchOp.Operation.INVALID:
						throw new InvalidOperationException($"Op type {BatchOp.Operation.INVALID} is not a valid op type for operation id {op.Id}");
					case BatchOp.Operation.GET:
						if (op.Id == null)
						{
							return BadRequest();
						}

						tasks[index] = GetImplAsync(op.Namespace.Value, op.Id).ContinueWith((t, _) =>
						{
							// TODO: This is very allocation heavy but given that the end result is a json object we can not really stream this anyway
							using BlobContents blobContents = t.Result;

							using MemoryStream ms = new MemoryStream();
							blobContents.Stream.CopyTo(ms);
							ms.Seek(0, SeekOrigin.Begin);
							string str = Convert.ToBase64String(ms.ToArray());
							return (object?) str;
						}, null, TaskScheduler.Current);
						break;
					case BatchOp.Operation.HEAD:
						if (op.Id == null)
						{
							return BadRequest();
						}

						tasks[index] = _storage.ExistsAsync(op.Namespace.Value, op.Id)
							.ContinueWith((t,_) => t.Result ? (object?) null : op.Id, null, TaskScheduler.Current);
						break;
					case BatchOp.Operation.PUT:
						{
							if (op.Content == null)
							{
								return BadRequest();
							}

							if (op.Id == null)
							{
								return BadRequest();
							}

							using MemoryBufferedPayload payload = new MemoryBufferedPayload(op.Content);
							tasks[index] = _storage.PutObjectAsync(op.Namespace.Value, payload, op.Id).ContinueWith((t, _) => (object?) t.Result, null, TaskScheduler.Current);
							break;
						}
					case BatchOp.Operation.DELETE:
						if (op.Id == null)
						{
							return BadRequest();
						}

						tasks[index] = DeleteImplAsync(op.Namespace.Value, op.Id).ContinueWith((t, _) => (object?) null, null, TaskScheduler.Current);
						break;
					default:
						throw new NotImplementedException($"{op.Op} is not a support op type");
				}
			}

			await Task.WhenAll(tasks);

			object?[] results = tasks.Select(t => t.Result).ToArray();

			return Ok(results);
		}
	}

	public class HeadMultipleResponse
	{
		[CbField("needs")]
		public BlobId[] Needs { get; set; } = null!;
	}
}