Test loading a not existing blob (and fix behaviour for that case)

src/blobstore/implementations/ondisk/CMakeLists.txt

@@ -1,3 +1,3 @@
-add_library(blobstore_ondisk Data.cpp OnDiskBlob.cpp OnDiskBlobStore.cpp FileAlreadyExistsException.cpp)
+add_library(blobstore_ondisk Data.cpp OnDiskBlob.cpp OnDiskBlobStore.cpp FileAlreadyExistsException.cpp FileDoesntExistException.cpp)
 
 target_link_libraries(blobstore_ondisk boost_filesystem boost_system)

src/blobstore/implementations/ondisk/Data.cpp

@@ -1,4 +1,6 @@
-#include <blobstore/implementations/ondisk/Data.h>
+#include "Data.h"
+
+#include "FileDoesntExistException.h"
 
 #include <stdexcept>
 #include <fstream>
@@ -56,6 +58,7 @@ void Data::StoreToFile(const bf::path &filepath) const {
 
 Data Data::LoadFromFile(const bf::path &filepath) {
   ifstream file(filepath.c_str(), ios::binary);
+  _assertFileExists(file, filepath);
   size_t size = _getStreamSize(file);
 
   Data result(size);
@@ -63,6 +66,12 @@ Data Data::LoadFromFile(const bf::path &filepath) {
   return result;
 }
 
+void Data::_assertFileExists(const ifstream &file, const bf::path &filepath) {
+  if (!file.good()) {
+    throw FileDoesntExistException(filepath);
+  }
+}
+
 size_t Data::_getStreamSize(istream &stream) {
   auto current_pos = stream.tellg();
 

src/blobstore/implementations/ondisk/Data.h

@@ -32,6 +32,7 @@ private:
   size_t _size;
   void *_data;
 
+  static void _assertFileExists(const std::ifstream &file, const boost::filesystem::path &filepath);
   static size_t _getStreamSize(std::istream &stream);
   void _readFromStream(std::istream &stream);
 

src/blobstore/implementations/ondisk/FileDoesntExistException.cpp

@@ -0,0 +1,19 @@
+#include <blobstore/implementations/ondisk/FileDoesntExistException.h>
+
+namespace bf = boost::filesystem;
+
+using std::runtime_error;
+using std::string;
+
+namespace blobstore {
+namespace ondisk {
+
+FileDoesntExistException::FileDoesntExistException(const bf::path &filepath)
+: runtime_error(string("The file ")+filepath.c_str()+" doesn't exist") {
+}
+
+FileDoesntExistException::~FileDoesntExistException() {
+}
+
+} /* namespace ondisk */
+} /* namespace blobstore */

src/blobstore/implementations/ondisk/FileDoesntExistException.h

@@ -0,0 +1,21 @@
+#pragma once
+#ifndef BLOBSTORE_IMPLEMENTATIONS_ONDISK_FILEDOESNTEXISTEXCEPTION_H_
+#define BLOBSTORE_IMPLEMENTATIONS_ONDISK_FILEDOESNTEXISTEXCEPTION_H_
+
+#include <boost/filesystem/path.hpp>
+
+#include <stdexcept>
+
+namespace blobstore {
+namespace ondisk {
+
+class FileDoesntExistException: public std::runtime_error {
+public:
+  FileDoesntExistException(const boost::filesystem::path &filepath);
+  virtual ~FileDoesntExistException();
+};
+
+} /* namespace ondisk */
+} /* namespace blobstore */
+
+#endif

src/test/blobstore/ondisk/OnDiskBlobLoadTest.cpp

@@ -5,6 +5,7 @@
 
 #include "blobstore/implementations/ondisk/OnDiskBlob.h"
 #include "blobstore/implementations/ondisk/Data.h"
+#include "blobstore/implementations/ondisk/FileDoesntExistException.h"
 
 #include <fstream>
 
@@ -64,4 +65,10 @@ TEST_P(OnDiskBlobLoadTest, LoadedDataIsCorrect) {
   EXPECT_BLOB_DATA_EQ(randomData, *blob);
 }
 
-//TODO Test file doesn't exist
+TEST_F(OnDiskBlobLoadTest, LoadNotExistingBlob) {
+  TempFile file2(false); // Pass false, so the file isn't created.
+  EXPECT_THROW(
+      OnDiskBlob::LoadFromDisk(file2.path()),
+      FileDoesntExistException
+  );
+}