Fix Archive::describe to include sub-archives (#188) (#189)

C++: Making Archive::describe describe resources recursively.

Fixes #189 188

Author: InfinityByTen

flatdata-cpp/README.md

@@ -4,12 +4,12 @@ C++ 11 implementation of `flatdata`
 
 ## Building
 
-First, build `flatdata-cpp` and install the requirements of the generator.
+First, install the requirements of the generator and build `flatdata-cpp`.
 
 ```shell
-pip3 install -r requirements.txt
-mkdir build
-cd build
+pip3 install -r flatdata-generator/requirements.txt
+cd flatdata-cpp
+mkdir build && cd build
 cmake ..
 make
 make test # optional

flatdata-cpp/include/flatdata/Archive.h

@@ -46,7 +46,7 @@ class Archive
     /**
      * @brief Returns text description of the archive and its resources' state.
      */
-    std::string describe( ) const;
+    std::string describe( size_t nest_level = 0u ) const;
 
     /**
      * @brief Returns archive name. Is implemented by the concrete archive instances.
@@ -60,13 +60,15 @@ class Archive
 
 protected:
     template < typename ResourceType >
-    static void describe_resource( std::ostream& stream,
+    static void describe_resource( size_t nest_level,
+                                   std::ostream& stream,
                                    const char* name,
                                    const ResourceType& resource,
                                    bool too_large = false );
 
     template < typename ResourceType >
-    static void describe_resource( std::ostream& stream,
+    static void describe_resource( size_t nest_level,
+                                   std::ostream& stream,
                                    const char* name,
                                    const boost::optional< ResourceType >& resource,
                                    bool too_large = false );
@@ -107,7 +109,9 @@ class Archive
                                bool optional,
                                bool loaded,
                                const char* details,
-                               bool too_large );
+                               bool are_details_nested,
+                               bool too_large,
+                               size_t nest_level );
 
 private:
     /**
@@ -120,7 +124,7 @@ class Archive
      * @brief Describes all resources provided by the archive.
      * Is implemented by the concrete archive instances.
      */
-    virtual void describe_resources( std::ostream& stream ) const = 0;
+    virtual void describe_resources( std::ostream& stream, size_t nest_level ) const = 0;
 
 private:
     std::shared_ptr< flatdata::ResourceStorage > m_storage;
@@ -130,28 +134,52 @@ class Archive
 
 // -------------------------------------------------------------------------------------------------
 
+template < typename ResourceType >
+std::string
+get_description( const ResourceType& resource, bool is_archive, size_t nest_level )
+{
+    std::string description;
+    if ( is_archive )
+    {
+        ++nest_level;
+    }
+    description = resource.describe( nest_level );
+    return description;
+}
+
 template < typename ResourceType >
 void
-Archive::describe_resource( std::ostream& stream,
+Archive::describe_resource( size_t nest_level,
+                            std::ostream& stream,
                             const char* name,
                             const ResourceType& resource,
                             bool too_large )
 {
-    auto initialized = static_cast< bool >( resource );
-    describe_impl( stream, name, false, static_cast< bool >( resource ),
-                   initialized ? resource.describe( ).c_str( ) : "N/A", too_large );
+    const auto initialized = static_cast< bool >( resource );
+    const bool is_archive = std::is_base_of< Archive, ResourceType >::value;
+
+    describe_impl( stream, name, false, initialized,
+                   get_description( resource, is_archive, nest_level ).c_str( ), is_archive,
+                   too_large, nest_level );
 }
 
 template < typename ResourceType >
 void
-Archive::describe_resource( std::ostream& stream,
+Archive::describe_resource( size_t nest_level,
+                            std::ostream& stream,
                             const char* name,
                             const boost::optional< ResourceType >& resource,
                             bool too_large )
 {
-    auto initialized = static_cast< bool >( resource );
+    const auto initialized = static_cast< bool >( resource );
+    const bool is_archive = std::is_base_of< Archive, ResourceType >::value;
+
+    const ResourceType ref = initialized ? *resource         // valid ref
+                                         : ResourceType( );  // ref to dummy, not used
+
     describe_impl( stream, name, true, initialized ? static_cast< bool >( *resource ) : false,
-                   initialized ? resource->describe( ).c_str( ) : "N/A", too_large );
+                   get_description( ref, is_archive, nest_level ).c_str( ), is_archive, too_large,
+                   nest_level );
 }
 
 template < typename ResourceType >

flatdata-cpp/include/flatdata/ArrayView.h

@@ -44,7 +44,7 @@ class ArrayView
 
     size_t size_in_bytes( ) const;
     size_t size( ) const;
-    std::string describe( ) const;
+    std::string describe( size_t nest_level = 0u ) const;
 
     bool empty( ) const;
 

flatdata-cpp/include/flatdata/MemoryDescriptor.h

@@ -31,10 +31,17 @@ struct MemoryDescriptor
     }
 
     std::string
-    describe( ) const
+    describe( size_t nest_level = 0 ) const
     {
         std::ostringstream ss;
-        ss << "Raw data of size " << m_size;
+        if ( this->operator bool( ) )
+        {
+            ss << "Raw data of size " << m_size;
+        }
+        else
+        {
+            ss << "Uninitialized Raw data";
+        }
         return ss.str( );
     }
 

flatdata-cpp/include/flatdata/MultiArrayView.h

@@ -130,7 +130,7 @@ class MultiArrayView
     }
 
     size_t size( ) const;
-    std::string describe( ) const;
+    std::string describe( size_t unused = 0 ) const;
     explicit operator bool( ) const;
 
     template < typename ElementType >
@@ -195,11 +195,17 @@ MultiArrayView< IndexType, Args... >::size( ) const
 }
 
 template < typename IndexType, typename... Args >
-std::string
-MultiArrayView< IndexType, Args... >::describe( ) const
+std::string MultiArrayView< IndexType, Args... >::describe( size_t /*unused*/ ) const
 {
     std::ostringstream ss;
-    ss << "MultiArray of size " << size( ) << ", with index: " << m_index.describe( );
+    if ( this->operator bool( ) )
+    {
+        ss << "MultiArray of size " << size( ) << ", with index: " << m_index.describe( );
+    }
+    else
+    {
+        ss << "Uninitialized MultiArray";
+    }
     return ss.str( );
 }
 

flatdata-cpp/include/flatdata/internal/ArrayView.inl

@@ -136,11 +136,17 @@ ArrayView< T >::end( ) const
 }
 
 template < typename T >
-std::string
-ArrayView< T >::describe( ) const
+std::string ArrayView< T >::describe( size_t /*unused*/ ) const
 {
     std::ostringstream ss;
-    ss << "Array of size: " << size( ) << " in " << size_in_bytes( ) << " bytes";
+    if ( !empty( ) )
+    {
+        ss << "Array of size: " << size( ) << " in " << size_in_bytes( ) << " bytes";
+    }
+    else
+    {
+        ss << "Uninitialized Array";
+    }
     return ss.str( );
 }
 

flatdata-cpp/src/Archive.cpp

@@ -10,6 +10,8 @@
 
 namespace flatdata
 {
+constexpr size_t TAB_WIDTH = 4;
+
 Archive::Archive( std::shared_ptr< flatdata::ResourceStorage > storage )
     : m_storage( std::move( storage ) )
 {
@@ -226,43 +228,69 @@ compute_diff( const char* expected, const char* found )
 }
 
 std::string
-Archive::describe( ) const
+Archive::describe( size_t nest_level ) const
 {
+    const auto newl = std::string( "\n" );
+    const auto hline = std::string( 80, '=' ) + newl;
+    const auto empty = std::string( "" );
+    const bool is_root_node = ( nest_level == 0 );
+
     std::ostringstream result;
-    static const char* hline
-        = "================================================================================";
-    result << hline << std::endl
-           << "Flatdata Archive: " << name( ) << std::endl
-           << hline << std::endl;
+
     if ( !m_storage )
     {
-        result << "  FATAL: Resource storage not initialized. Please check archive path."
-               << std::endl
-               << hline << std::endl;
-        return result.str( );
+        if ( is_root_node )
+        {
+            result << hline << "FATAL: Resource storage not initialized. Please check archive path."
+                   << newl;
+        }
+        else
+        {
+            result << "Uninitialized Archive " << name( );
+        }
     }
 
-    if ( !m_signature )
+    if ( m_storage && !m_signature )
     {
-        result << "  FATAL: Archive signature does not match software expectations." << std::endl
-               << hline << std::endl;
+        result << ( is_root_node ? hline : empty )
+               << "FATAL: Archive signature does not match software expectations."
+               << ( is_root_node ? newl : empty ) << hline;
         result << compute_diff(
             schema( ),
             m_storage->read_schema( internal::signature_name( name( ) ).c_str( ) ).char_ptr( ) );
     }
 
-    if ( !m_is_open )
+    if ( m_storage && !m_is_open )
     {
-        result << "  FATAL: Archive initialization failed. Failed loading mandatory resources."
+        // Error propagated to root and storage is not initialized in respective child. No root
+        // check needed.
+        result << hline
+               << "FATAL: Archive initialization failed. Failed loading mandatory resources."
                << std::endl;
     }
 
-    result << std::endl
-           << "Resource                             Optional  Too Large  Loaded    Details"
-           << std::endl
-           << hline << std::endl;
-    describe_resources( result );
-    result << hline << std::endl;
+    if ( is_root_node )
+    {
+        result << hline << "Flatdata Archive: " << name( ) << std::endl
+               << hline
+               << "Resource                             Optional  Too Large  Loaded    Details"
+               << std::endl
+               << hline;
+    }
+    else
+    {
+        const std::string indent( ( nest_level - 1 ) * TAB_WIDTH, ' ' );
+        result << newl + indent + std::string( "|" ) + newl + indent + std::string( "|->" )
+               << " Flatdata Archive: " << name( ) << std::endl;
+    }
+
+    describe_resources( result, nest_level );
+
+    if ( is_root_node )
+    {
+        result << hline;
+    }
+
     return result.str( );
 }
 
@@ -272,17 +300,18 @@ Archive::describe_impl( std::ostream& stream,
                         bool optional,
                         bool loaded,
                         const char* details,
-                        bool too_large )
+                        bool has_nested_details,
+                        bool too_large,
+                        size_t nest_level )
 {
-    auto oldw = stream.width( );
-    auto oldfill = stream.fill( );
-    stream << std::left << std::setw( 37 ) << std::setfill( ' ' )
+    const std::string indent( nest_level * TAB_WIDTH, ' ' );
+    size_t offset = indent.size( );
+    stream << indent << std::left << std::setw( 37 - offset ) << std::setfill( ' ' )
            << std::string( name ).substr( 0, 30 ) << std::left << std::setw( 10 )
            << std::setfill( ' ' ) << ( optional ? "YES" : "NO" ) << std::left << std::setw( 11 )
            << std::setfill( ' ' ) << ( too_large ? "YES" : "NO" ) << std::left << std::setw( 10 )
            << std::setfill( ' ' ) << ( static_cast< bool >( loaded ) ? "YES" : "NO" ) << details
-           << std::endl;
-    stream << std::setw( oldw ) << std::setfill( oldfill );
+           << ( has_nested_details ? "" : "\n" );
 }
 
 }  // namespace flatdata