From b25dab9e6c7abba9a115adde7ca3259fb89a3124 Mon Sep 17 00:00:00 2001
From: Gerhard Raven <gerhard.raven@nikhef.nl>
Date: Tue, 15 Mar 2022 09:33:29 +0100
Subject: [PATCH] Extend IFileAccess interface with a `read` function
`IFileAccess;:read` returns an `optional<string>` with the content of the
requested file -- if it can be read. Otherwise it returns an 'empty'
optional.
---
GaudiKernel/include/GaudiKernel/IFileAccess.h | 14 +++-
.../include/GaudiKernel/ServiceHandle.h | 4 +-
GaudiUtils/src/component/FileReadTool.cpp | 44 +++++++----
GaudiUtils/src/component/FileReadTool.h | 36 ---------
GaudiUtils/src/component/VFSSvc.cpp | 74 ++++++++++++++-----
GaudiUtils/src/component/VFSSvc.h | 70 ------------------
6 files changed, 97 insertions(+), 145 deletions(-)
delete mode 100644 GaudiUtils/src/component/FileReadTool.h
delete mode 100644 GaudiUtils/src/component/VFSSvc.h
diff --git a/GaudiKernel/include/GaudiKernel/IFileAccess.h b/GaudiKernel/include/GaudiKernel/IFileAccess.h
index ae195089c7..07e438c884 100644
--- a/GaudiKernel/include/GaudiKernel/IFileAccess.h
+++ b/GaudiKernel/include/GaudiKernel/IFileAccess.h
@@ -15,6 +15,7 @@
#include "GaudiKernel/IInterface.h"
#include <istream>
#include <memory>
+#include <optional>
#include <string>
#include <vector>
@@ -28,12 +29,21 @@
class GAUDI_API IFileAccess : virtual public IInterface {
public:
/// InterfaceID
- DeclareInterfaceID( IFileAccess, 3, 0 );
+ DeclareInterfaceID( IFileAccess, 3, 1 );
/// Find the URL and returns a unique_ptr to an input stream interface of an
/// object that can be used to read from the file the URL is pointing to.
/// Returns an empty pointer if the URL cannot be resolved.
- virtual std::unique_ptr<std::istream> open( const std::string& url ) = 0;
+ virtual std::unique_ptr<std::istream> open( std::string const& url ) = 0;
+
+ /// Find the URL and returns an optional<string> to the content of
+ /// the file the URL is pointing to.
+ /// Returns an 'unengaged' optional if the URL cannot be resolved.
+ virtual std::optional<std::string> read( std::string const& url ) {
+ auto is = open( url );
+ if ( !is || !is->good() ) return std::nullopt;
+ return std::string{ std::istreambuf_iterator<char>{ *is }, std::istreambuf_iterator<char>{} };
+ }
/// Protocols supported by the instance.
virtual const std::vector<std::string>& protocols() const = 0;
diff --git a/GaudiKernel/include/GaudiKernel/ServiceHandle.h b/GaudiKernel/include/GaudiKernel/ServiceHandle.h
index 06d395be5e..93af3f82b6 100644
--- a/GaudiKernel/include/GaudiKernel/ServiceHandle.h
+++ b/GaudiKernel/include/GaudiKernel/ServiceHandle.h
@@ -77,9 +77,7 @@ public:
/** Retrieve the Service. Release existing Service if needed.
Function must be repeated here to avoid hiding the function retrieve( T*& ) */
- StatusCode retrieve() const { // not really const, because it updates m_pObject
- return GaudiHandle<T>::retrieve();
- }
+ using GaudiHandle<T>::retrieve;
// /** Release the Service.
// Function must be repeated here to avoid hiding the function release( T*& ) */
diff --git a/GaudiUtils/src/component/FileReadTool.cpp b/GaudiUtils/src/component/FileReadTool.cpp
index b01f9add6b..573d6d1286 100644
--- a/GaudiUtils/src/component/FileReadTool.cpp
+++ b/GaudiUtils/src/component/FileReadTool.cpp
@@ -8,24 +8,36 @@
* granted to it by virtue of its status as an Intergovernmental Organization *
* or submit itself to any jurisdiction. *
\***********************************************************************************/
-#include "FileReadTool.h"
+#include "GaudiKernel/AlgTool.h"
+#include "GaudiKernel/IFileAccess.h"
#include <fstream>
-DECLARE_COMPONENT( FileReadTool )
+/** @class FileReadTool FileReadTool.h
+ *
+ * Basic implementation of the IFileAccess interface.
+ * This tool simply takes a path to a file as url and return the std::istream interface
+ * of std::ifstream.
+ *
+ * @author Marco Clemencic
+ * @date 2008-01-18
+ */
+struct FileReadTool : extends<AlgTool, IFileAccess> {
+ /// Standard constructor
+ using extends::extends;
+
+ std::unique_ptr<std::istream> open( std::string const& url ) override {
+ // remove the optional "file://" from the beginning of the url
+ constexpr auto prefix = std::string_view{ "file://" };
+ return std::make_unique<std::ifstream>( url.compare( 0, prefix.size(), prefix ) == 0 ? url.substr( prefix.size() )
+ : url );
+ }
-std::unique_ptr<std::istream> FileReadTool::open( const std::string& url ) {
- // remove the optional "file://" from the beginning of the url
- std::string path;
- if ( url.compare( 0, 7, "file://" ) == 0 ) {
- path = url.substr( 7 );
- } else {
- path = url;
+ /// Protocols supported by the instance.
+ const std::vector<std::string>& protocols() const override {
+ /// Vector of supported protocols.
+ static const std::vector<std::string> s_protocols = { { "file" } };
+ return s_protocols;
}
- return std::make_unique<std::ifstream>( path );
-}
+};
-const std::vector<std::string>& FileReadTool::protocols() const {
- /// Vector of supported protocols.
- static const std::vector<std::string> s_protocols = { { "file" } };
- return s_protocols;
-}
+DECLARE_COMPONENT( FileReadTool )
diff --git a/GaudiUtils/src/component/FileReadTool.h b/GaudiUtils/src/component/FileReadTool.h
deleted file mode 100644
index bcc061e81b..0000000000
--- a/GaudiUtils/src/component/FileReadTool.h
+++ /dev/null
@@ -1,36 +0,0 @@
-/***********************************************************************************\
-* (c) Copyright 1998-2019 CERN for the benefit of the LHCb and ATLAS collaborations *
-* *
-* This software is distributed under the terms of the Apache version 2 licence, *
-* copied verbatim in the file "LICENSE". *
-* *
-* In applying this licence, CERN does not waive the privileges and immunities *
-* granted to it by virtue of its status as an Intergovernmental Organization *
-* or submit itself to any jurisdiction. *
-\***********************************************************************************/
-#ifndef _FILEREADTOOL_H
-#define _FILEREADTOOL_H
-
-#include "GaudiKernel/AlgTool.h"
-#include "GaudiKernel/IFileAccess.h"
-
-/** @class FileReadTool FileReadTool.h
- *
- * Basic implementation of the IFileAccess interface.
- * This tool simply takes a path to a file as url and return the std::istream interface
- * of std::ifstream.
- *
- * @author Marco Clemencic
- * @date 2008-01-18
- */
-struct FileReadTool : extends<AlgTool, IFileAccess> {
- /// Standard constructor
- using extends::extends;
-
- std::unique_ptr<std::istream> open( const std::string& url ) override;
-
- /// Protocols supported by the instance.
- const std::vector<std::string>& protocols() const override;
-};
-
-#endif // _FILEREADTOOL_H
diff --git a/GaudiUtils/src/component/VFSSvc.cpp b/GaudiUtils/src/component/VFSSvc.cpp
index a40b718ec1..85b29db6e7 100644
--- a/GaudiUtils/src/component/VFSSvc.cpp
+++ b/GaudiUtils/src/component/VFSSvc.cpp
@@ -8,11 +8,58 @@
* granted to it by virtue of its status as an Intergovernmental Organization *
* or submit itself to any jurisdiction. *
\***********************************************************************************/
-#include "VFSSvc.h"
-
+#include "GaudiKernel/HashMap.h"
#include "GaudiKernel/IAlgTool.h"
+#include "GaudiKernel/IFileAccess.h"
#include "GaudiKernel/IToolSvc.h"
#include "GaudiKernel/MsgStream.h"
+#include "GaudiKernel/Service.h"
+#include <list>
+
+/** @class VFSSvc VFSSvc.h
+ *
+ * Simple service that allows to read files independently from the storage.
+ * The service uses tools to resolve URLs and serve the files as input streams.
+ * The basic implementations read from the filesystem, and simple extensions allow to
+ * read from databases, web...
+ *
+ * @author Marco Clemencic
+ * @date 2008-01-18
+ */
+
+class VFSSvc : public extends<Service, IFileAccess> {
+public:
+ /// Inherited constructor
+ using extends::extends;
+ /// Initialize Service
+ StatusCode initialize() override;
+ /// Finalize Service
+ StatusCode finalize() override;
+
+ /// @see IFileAccess::open
+ std::unique_ptr<std::istream> open( std::string const& url ) override;
+
+ /// @see IFileAccess::protocols
+ const std::vector<std::string>& protocols() const override;
+
+private:
+ Gaudi::Property<std::vector<std::string>> m_urlHandlersNames{
+ this, "FileAccessTools", { { "FileReadTool" } }, "List of tools implementing the IFileAccess interface." };
+ Gaudi::Property<std::string> m_fallBackProtocol{ this, "FallBackProtocol", "file",
+ "URL prefix to use if the prefix is not present." };
+
+ /// Protocols registered
+ std::vector<std::string> m_protocols;
+
+ /// Map of the tools handling the known protocols.
+ GaudiUtils::HashMap<std::string, std::vector<IFileAccess*>> m_urlHandlers;
+
+ /// Handle to the tool service.
+ SmartIF<IToolSvc> m_toolSvc;
+
+ /// List of acquired tools (needed to release them).
+ std::vector<IAlgTool*> m_acquiredTools;
+};
DECLARE_COMPONENT( VFSSvc )
@@ -73,13 +120,13 @@ StatusCode VFSSvc::finalize() {
return Service::finalize();
}
//------------------------------------------------------------------------------
-std::unique_ptr<std::istream> VFSSvc::open( const std::string& url ) {
+std::unique_ptr<std::istream> VFSSvc::open( std::string const& url ) {
// get the url prefix endpos
auto pos = url.find( "://" );
- if ( std::string::npos == pos ) {
+ if ( url.npos == pos ) {
// no url prefix, try fallback protocol
- return VFSSvc::open( m_fallBackProtocol + "://" + url );
+ return VFSSvc::open( std::string{ m_fallBackProtocol }.append( "://" ).append( url ) );
}
const std::string url_prefix( url, 0, pos );
@@ -87,7 +134,7 @@ std::unique_ptr<std::istream> VFSSvc::open( const std::string& url ) {
if ( handlers == m_urlHandlers.end() ) {
// if we do not have a handler for the URL prefix,
// use the fall back one
- return VFSSvc::open( m_fallBackProtocol + url.substr( pos ) );
+ return VFSSvc::open( std::string{ m_fallBackProtocol }.append( url.substr( pos ) ) );
}
std::unique_ptr<std::istream> out; // this might help RVO
@@ -98,23 +145,14 @@ std::unique_ptr<std::istream> VFSSvc::open( const std::string& url ) {
}
return out;
}
-//------------------------------------------------------------------------------
-namespace {
- /// small helper to select the first element of a pair
- /// (e.g. the key of a map value type)
- constexpr struct select1st_t {
- template <typename S, typename T>
- const S& operator()( const std::pair<S, T>& x ) const {
- return x.first;
- }
- } select1st{};
-} // namespace
+//------------------------------------------------------------------------------
const std::vector<std::string>& VFSSvc::protocols() const {
if ( m_protocols.empty() ) {
// prepare the list of handled protocols
std::transform( m_urlHandlers.begin(), m_urlHandlers.end(),
- std::back_inserter( const_cast<VFSSvc*>( this )->m_protocols ), select1st );
+ std::back_inserter( const_cast<VFSSvc*>( this )->m_protocols ),
+ []( const auto& pair ) { return pair.first; } );
}
return m_protocols;
}
diff --git a/GaudiUtils/src/component/VFSSvc.h b/GaudiUtils/src/component/VFSSvc.h
deleted file mode 100644
index c4417f4b67..0000000000
--- a/GaudiUtils/src/component/VFSSvc.h
+++ /dev/null
@@ -1,70 +0,0 @@
-/***********************************************************************************\
-* (c) Copyright 1998-2019 CERN for the benefit of the LHCb and ATLAS collaborations *
-* *
-* This software is distributed under the terms of the Apache version 2 licence, *
-* copied verbatim in the file "LICENSE". *
-* *
-* In applying this licence, CERN does not waive the privileges and immunities *
-* granted to it by virtue of its status as an Intergovernmental Organization *
-* or submit itself to any jurisdiction. *
-\***********************************************************************************/
-#ifndef GaudiSvc_VFSSvc_H
-#define GaudiSvc_VFSSvc_H 1
-
-// Include files
-#include "GaudiKernel/HashMap.h"
-#include "GaudiKernel/IFileAccess.h"
-#include "GaudiKernel/Service.h"
-
-#include <list>
-
-// Forward declarations
-class IToolSvc;
-class IAlgTool;
-
-/** @class VFSSvc VFSSvc.h
- *
- * Simple service that allows to read files independently from the storage.
- * The service uses tools to resolve URLs and serve the files as input streams.
- * The basic implementations read from the filesystem, and simple extensions allow to
- * read from databases, web...
- *
- * @author Marco Clemencic
- * @date 2008-01-18
- */
-
-class VFSSvc : public extends<Service, IFileAccess> {
-public:
- /// Inherited constructor
- using extends::extends;
- /// Initialize Service
- StatusCode initialize() override;
- /// Finalize Service
- StatusCode finalize() override;
-
- /// @see IFileAccess::open
- std::unique_ptr<std::istream> open( const std::string& url ) override;
-
- /// @see IFileAccess::protocols
- const std::vector<std::string>& protocols() const override;
-
-private:
- Gaudi::Property<std::vector<std::string>> m_urlHandlersNames{
- this, "FileAccessTools", { { "FileReadTool" } }, "List of tools implementing the IFileAccess interface." };
- Gaudi::Property<std::string> m_fallBackProtocol{ this, "FallBackProtocol", "file",
- "URL prefix to use if the prefix is not present." };
-
- /// Protocols registered
- std::vector<std::string> m_protocols;
-
- /// Map of the tools handling the known protocols.
- GaudiUtils::HashMap<std::string, std::vector<IFileAccess*>> m_urlHandlers;
-
- /// Handle to the tool service.
- SmartIF<IToolSvc> m_toolSvc;
-
- /// List of acquired tools (needed to release them).
- std::vector<IAlgTool*> m_acquiredTools;
-};
-
-#endif
--
GitLab