Rearrange files and add InitializeDownload logic and tests DynamicsVa…

…lue/fake-xrm-easy#157

src/FakeXrmEasy.Core/FileStorage/Db/Exceptions/CouldNotAddFileException.cs

@@ -0,0 +1,12 @@
+using System;
+
+namespace FakeXrmEasy.Core.FileStorage.Db.Exceptions
+{
+    public class CouldNotAddFileException: Exception
+    {
+        public CouldNotAddFileException(): base("A file could not be added")
+        {
+
+        }
+    }
+}

src/FakeXrmEasy.Core/FileStorage/Db/Exceptions/FileToDownloadNotFoundException.cs

@@ -0,0 +1,22 @@
+using System;
+using Microsoft.Xrm.Sdk;
+
+namespace FakeXrmEasy.Core.FileStorage.Db.Exceptions
+{
+    /// <summary>
+    /// Exception raised when downloading a file block for a database record and column that doesn't actually have a file against it
+    /// </summary>
+    public class FileToDownloadNotFoundException: Exception
+    {
+        /// <summary>
+        /// Default constructor
+        /// </summary>
+        /// <param name="entityReference">An entity reference of the record</param>
+        /// <param name="fileAttributeName">The column where a file was not found</param>
+        public FileToDownloadNotFoundException(EntityReference entityReference, string fileAttributeName) 
+            : base($"A file was not found for record with logical name '{entityReference.LogicalName}' and Id '{entityReference.Id.ToString()}' in column '{fileAttributeName}'")
+        {
+
+        }
+    }
+}

src/FakeXrmEasy.Core/FileStorage/Db/FileDownloadSession.cs

@@ -0,0 +1,11 @@
+using FakeXrmEasy.Core.FileStorage.Download;
+
+namespace FakeXrmEasy.Core.FileStorage.Db
+{
+    internal class FileDownloadSession
+    {
+        internal string FileDownloadSessionId { get; set; }
+        internal FileDownloadProperties Properties { get; set; }
+        internal FileAttachment File { get; set; }
+    }
+}

src/FakeXrmEasy.Core/FileStorage/Db/FileUploadSession.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Linq;
 using FakeXrmEasy.Core.FileStorage.Db.Exceptions;
+using FakeXrmEasy.Core.FileStorage.Upload;
 
 namespace FakeXrmEasy.Core.FileStorage.Db
 {

src/FakeXrmEasy.Core/FileStorage/Db/IInMemoryFileDbDownloader.cs

@@ -0,0 +1,16 @@
+using System.Collections.Generic;
+using FakeXrmEasy.Core.FileStorage.Download;
+
+namespace FakeXrmEasy.Core.FileStorage.Db
+{
+    internal interface IInMemoryFileDbDownloader
+    {
+        string InitFileDownloadSession(FileDownloadProperties fileDownloadProperties);
+
+        FileDownloadSession GetFileDownloadSession(string fileDownloadSessionId);
+
+        List<FileDownloadSession> GetAllFileDownloadSessions();
+
+        byte[] DownloadFileBlock(DownloadBlockProperties uploadBlockProperties);
+    }
+}

src/FakeXrmEasy.Core/FileStorage/Db/IInMemoryFileDbInternal.cs → src/FakeXrmEasy.Core/FileStorage/Db/IInMemoryFileDbUploader.cs

@@ -1,8 +1,9 @@
 using System.Collections.Generic;
+using FakeXrmEasy.Core.FileStorage.Upload;
 
 namespace FakeXrmEasy.Core.FileStorage.Db
 {
-    internal interface IInMemoryFileDbInternal
+    internal interface IInMemoryFileDbUploader
     {
         /// <summary>
         /// Inits a file upload session against this InMemoryFileDb

src/FakeXrmEasy.Core/FileStorage/Db/InMemoryFileDb.cs

@@ -4,15 +4,20 @@
 using System.Linq;
 using FakeXrmEasy.Core.Db;
 using FakeXrmEasy.Core.FileStorage.Db.Exceptions;
+using FakeXrmEasy.Core.FileStorage.Download;
+using FakeXrmEasy.Core.FileStorage.Upload;
 using Microsoft.Xrm.Sdk;
+#if FAKE_XRM_EASY_9
 using Microsoft.Xrm.Sdk.Metadata;
+#endif
 
 namespace FakeXrmEasy.Core.FileStorage.Db
 {
-    internal class InMemoryFileDb : IInMemoryFileDbInternal
+    internal class InMemoryFileDb : IInMemoryFileDbUploader, IInMemoryFileDbDownloader
     {
         private readonly ConcurrentDictionary<string, FileUploadSession> _uncommittedFileUploads;
         private readonly ConcurrentDictionary<string, FileAttachment> _files;
+        private readonly ConcurrentDictionary<string, FileDownloadSession> _fileDownloadSessions;
         private readonly InMemoryDb _db;
 
         internal const string FILE_ATTACHMENT_TABLE_NAME = "fileattachment";
@@ -22,11 +27,12 @@ internal InMemoryFileDb(InMemoryDb db)
             _db = db;
             _uncommittedFileUploads = new ConcurrentDictionary<string, FileUploadSession>();
             _files = new ConcurrentDictionary<string, FileAttachment>();
+            _fileDownloadSessions = new ConcurrentDictionary<string, FileDownloadSession>();
         }
 
         public string InitFileUploadSession(FileUploadProperties fileUploadProperties)
         {
-            ValidateEntityReference(fileUploadProperties);
+            ValidateEntityReference(fileUploadProperties.Target);
 
             string fileContinuationToken = Guid.NewGuid().ToString();
             _uncommittedFileUploads.GetOrAdd(fileContinuationToken, new FileUploadSession()
@@ -37,11 +43,11 @@ public string InitFileUploadSession(FileUploadProperties fileUploadProperties)
             return fileContinuationToken;
         }
 
-        private void ValidateEntityReference(FileUploadProperties fileUploadProperties)
+        private void ValidateEntityReference(EntityReference entityReference)
         {
-            if (!_db.ContainsEntityRecord(fileUploadProperties.Target.LogicalName, fileUploadProperties.Target.Id))
+            if (!_db.ContainsEntityRecord(entityReference.LogicalName, entityReference.Id))
             {
-                throw new RecordNotFoundException(fileUploadProperties.Target);
+                throw new RecordNotFoundException(entityReference);
             }
         }
 
@@ -62,11 +68,22 @@ public List<FileUploadSession> GetAllFileUploadSessions()
             return _uncommittedFileUploads.Values.ToList();
         }
 
-        public List<FileAttachment> GetAllFiles()
+        #region Internal File Manipulation
+        internal List<FileAttachment> GetAllFiles()
         {
             return _files.Values.ToList();
         }
 
+        internal void AddFile(FileAttachment fileAttachment)
+        {
+            var wasAdded = _files.TryAdd(fileAttachment.Id, fileAttachment);
+            if (!wasAdded)
+            {
+                throw new CouldNotAddFileException();
+            }
+        }
+        #endregion
+
         /// <summary>
         /// 
         /// </summary>
@@ -76,6 +93,7 @@ public IQueryable<FileAttachment> CreateQuery()
             return _files.Values.AsQueryable();
         }
 
+        #region Upload
         public string CommitFileUploadSession(CommitFileUploadSessionProperties commitProperties)
         {
             FileUploadSession fileUploadSession;
@@ -166,5 +184,65 @@ private void SaveFileAttachment(FileUploadSession fileUploadSession, FileAttachm
             record[fileUploadSession.Properties.FileAttributeName] = fileAttachment.Id;
             record[$"{fileUploadSession.Properties.FileAttributeName}_name"] = fileAttachment.FileName;
         }
+
+        #endregion
+
+        #region Download
+        public string InitFileDownloadSession(FileDownloadProperties fileDownloadProperties)
+        {
+            ValidateEntityReference(fileDownloadProperties.Target);
+            var file = CheckFileExists(fileDownloadProperties);
+
+            string fileContinuationToken = Guid.NewGuid().ToString();
+            _fileDownloadSessions.GetOrAdd(fileContinuationToken, new FileDownloadSession()
+            {
+                FileDownloadSessionId = fileContinuationToken,
+                Properties = new FileDownloadProperties(fileDownloadProperties),
+                File = file
+            });
+            return fileContinuationToken;
+        }
+
+        private FileAttachment CheckFileExists(FileDownloadProperties fileDownloadProperties)
+        {
+            var entityReference = fileDownloadProperties.Target;
+            var record = _db.GetTable(entityReference.LogicalName).GetById(entityReference.Id);
+            if (!record.Attributes.ContainsKey(fileDownloadProperties.FileAttributeName))
+            {
+                throw new FileToDownloadNotFoundException(entityReference, fileDownloadProperties.FileAttributeName);
+            }
+
+            var fileId = (string)record[fileDownloadProperties.FileAttributeName];
+
+            var exists = _files.TryGetValue(fileId, out var file);
+            if (!exists)
+            {
+                throw new FileToDownloadNotFoundException(entityReference, fileDownloadProperties.FileAttributeName);
+            }
+            return file;
+        }
+
+        public FileDownloadSession GetFileDownloadSession(string fileDownloadSessionId)
+        {
+            FileDownloadSession session = null;
+            var exists = _fileDownloadSessions.TryGetValue(fileDownloadSessionId, out session);
+            if (exists)
+            {
+                return session;
+            }
+
+            return null;
+        }
+
+        public List<FileDownloadSession> GetAllFileDownloadSessions()
+        {
+            return _fileDownloadSessions.Values.ToList();
+        }
+
+        public byte[] DownloadFileBlock(DownloadBlockProperties uploadBlockProperties)
+        {
+            throw new NotImplementedException();
+        }
+        #endregion
     }
 }

src/FakeXrmEasy.Core/FileStorage/Download/DownloadBlockProperties.cs

@@ -0,0 +1,9 @@
+namespace FakeXrmEasy.Core.FileStorage.Download
+{
+    internal class DownloadBlockProperties
+    {
+        internal string FileDownloadSessionId { get; set; }
+        internal long BlockLength { get; set; }
+        internal long Offset { get; set; }
+    }
+}

src/FakeXrmEasy.Core/FileStorage/Download/FileDownloadProperties.cs

@@ -0,0 +1,28 @@
+using Microsoft.Xrm.Sdk;
+
+namespace FakeXrmEasy.Core.FileStorage.Download
+{
+    internal class FileDownloadProperties
+    {
+        internal EntityReference Target { get; set; }
+        internal string FileAttributeName { get; set; }
+
+        internal FileDownloadProperties()
+        {
+
+        }
+
+        internal FileDownloadProperties(FileDownloadProperties other)
+        {
+            if (other.Target != null)
+            {
+                Target = new EntityReference(other.Target.LogicalName)
+                {
+                    Id = other.Target.Id
+                };
+            }
+
+            FileAttributeName = other.FileAttributeName;
+        }
+    }
+}

src/FakeXrmEasy.Core/FileStorage/CommitFileUploadSessionProperties.cs → src/FakeXrmEasy.Core/FileStorage/Upload/CommitFileUploadSessionProperties.cs

@@ -1,4 +1,4 @@
-namespace FakeXrmEasy.Core.FileStorage
+namespace FakeXrmEasy.Core.FileStorage.Upload
 {
     internal class CommitFileUploadSessionProperties
     {

src/FakeXrmEasy.Core/FileStorage/FileUploadProperties.cs → src/FakeXrmEasy.Core/FileStorage/Upload/FileUploadProperties.cs

@@ -1,7 +1,6 @@
-using FakeXrmEasy.Core.FileStorage.Db;
 using Microsoft.Xrm.Sdk;
 
-namespace FakeXrmEasy.Core.FileStorage
+namespace FakeXrmEasy.Core.FileStorage.Upload
 {
     /// <summary>
     /// Properties needed to initialize a file upload
@@ -12,7 +11,7 @@ internal class FileUploadProperties
         public string FileAttributeName { get; set; }
         public string FileName { get; set; }
 
-        public FileUploadProperties()
+        internal FileUploadProperties()
         {
 
         }
@@ -21,7 +20,7 @@ public FileUploadProperties()
         /// Copy constructor
         /// </summary>
         /// <param name="other"></param>
-        public FileUploadProperties(FileUploadProperties other)
+        internal FileUploadProperties(FileUploadProperties other)
         {
             if (other.Target != null)
             {

src/FakeXrmEasy.Core/FileStorage/UploadBlockProperties.cs → src/FakeXrmEasy.Core/FileStorage/Upload/UploadBlockProperties.cs

@@ -1,4 +1,4 @@
-namespace FakeXrmEasy.Core.FileStorage
+namespace FakeXrmEasy.Core.FileStorage.Upload
 {
     internal interface IUploadBlockProperties
     {

tests/FakeXrmEasy.Core.Tests/FileStorage/Db/FileUploadSessionTests.cs

@@ -2,6 +2,7 @@
 using FakeXrmEasy.Core.FileStorage;
 using FakeXrmEasy.Core.FileStorage.Db;
 using FakeXrmEasy.Core.FileStorage.Db.Exceptions;
+using FakeXrmEasy.Core.FileStorage.Upload;
 using Xunit;
 
 namespace FakeXrmEasy.Core.Tests.FileStorage.Db