lunchbox::PersistentMap Class Reference

Unified interface to save key-value pairs in a persistent store. More...

#include <persistentMap.h>

Inheritance diagram for lunchbox::PersistentMap:

Collaboration diagram for lunchbox::PersistentMap:

Public Member Functions
LUNCHBOX_API	PersistentMap (const std::string &uri=std::string())
	Construct a new persistent map. More...
LUNCHBOX_API	PersistentMap (const URI &uri)
	Construct a persistent map using an URI. More...
LUNCHBOX_API	~PersistentMap ()
	Destruct the persistent map. More...
template<class V >
bool	insert (const std::string &key, const V &value)
	Insert or update a value in the database. More...
template<class V >
bool	insert (const std::string &key, const std::vector< V > &values)
	Insert or update a vector of values in the database. More...
template<class V >
bool	insert (const std::string &key, const std::set< V > &values)
	Insert or update a set of values in the database. More...
LUNCHBOX_API std::string	operator[] (const std::string &key) const
	Retrieve a value for a key. More...
template<class V >
std::vector< V >	getVector (const std::string &key)
	Retrieve a value as a vector for a key. More...
template<class V >
std::set< V >	getSet (const std::string &key)
	Retrieve a value as a set for a key. More...
LUNCHBOX_API bool	contains (const std::string &key) const
template<>
bool	_insert (const std::string &k, const std::string &v, const boost::false_type &)

Static Public Member Functions
static LUNCHBOX_API bool	handles (const URI &uri)

Detailed Description

Unified interface to save key-value pairs in a persistent store.

Example:

/* Copyright (c) 2014 Stefan.Eilemann@epfl.ch
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License version 2.1 as published
 * by the Free Software Foundation.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more
 * details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with this library; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include <test.h>
#include <lunchbox/persistentMap.h>
#ifdef LUNCHBOX_USE_LEVELDB
#  include <leveldb/db.h>
#endif
#include <stdexcept>

using lunchbox::PersistentMap;

const int ints[] = { 17, 53, 42, 65535, 32768 };
const size_t numInts = sizeof( ints ) / sizeof( int );

template< class T > void insertVector( PersistentMap& map )
{
    std::vector< T > vector;
    for( size_t i = 0; i < numInts; ++i )
        vector.push_back( T( ints[ i ] ));

    TEST( map.insert( typeid( vector ).name(), vector ));
}

template< class T > void readVector( PersistentMap& map )
{
    const std::vector< T >& vector =
        map.getVector< T >( typeid( vector ).name( ));
    TEST( vector.size() ==  numInts );
    for( size_t i = 0; i < numInts; ++i )
        TEST( vector[ i ] == T( ints[i] ));
}

void setup( const std::string& uri )
{
    PersistentMap map( uri );
    TEST( map.insert( "the quick brown fox", "jumped over something" ));
    TESTINFO( map[ "the quick brown fox" ] == "jumped over something",
              map[ "the quick brown fox" ] );

    TEST( map.insert( "foo", "bar" ));
    TESTINFO( map[ "foo" ] == "bar",
              map[ "foo" ] << " length " << map[ "foo" ].length( ));
    TEST( map[ "bar" ].empty( ));

    TEST( map.insert( "hans", std::string( "dampf" )));
    TESTINFO( map[ "hans" ] == "dampf", map[ "hans" ] );

    insertVector< int >( map );
    insertVector< uint16_t >( map );
    readVector< int >( map );
    readVector< uint16_t >( map );

    std::set< int > set( ints, ints + numInts );
    TEST( map.insert( "std::set< int >", set ));
}

void read( const std::string& uri )
{
    PersistentMap map( uri );
    TEST( map[ "foo" ] == "bar" );
    TEST( map[ "bar" ].empty( ));

    readVector< int >( map );
    readVector< uint16_t >( map );

    const std::set< int >& set = map.getSet< int >( "std::set< int >" );
    TESTINFO( set.size() ==  numInts, set.size() << " != " << numInts );
    for( size_t i = 0; i < numInts; ++i )
        TESTINFO( set.find( ints[i] ) != set.end(),
                  ints[i] << " not found in set" );
}

void testGenericFailures()
{
    try
    {
        setup( "foobar://" );
    }
    catch( const std::runtime_error& )
    {
        return;
    }
    TESTINFO( false, "Missing exception" );
}

void testLevelDBFailures()
{
#ifdef LUNCHBOX_USE_LEVELDB
    try
    {
        setup( "leveldb:///doesnotexist/deadbeef/coffee" );
    }
    catch( const std::runtime_error& )
    {
        return;
    }
    TESTINFO( false, "Missing exception" );
#endif
}

int main( int, char** )
{
    try
    {
#ifdef LUNCHBOX_USE_LEVELDB
        setup( "" );
        setup( "leveldb://" );
        setup( "leveldb://persistentMap2.leveldb" );
        read( "" );
        read( "leveldb://" );
        read( "leveldb://persistentMap2.leveldb" );
#endif
    }
#ifdef LUNCHBOX_USE_LEVELDB
    catch( const leveldb::Status& status )
    {
        TESTINFO( !"exception", status.ToString( ));
    }
#endif
    catch( const std::runtime_error& error )
    {
        TESTINFO( !"exception", error.what( ));
    }

    testGenericFailures();
    testLevelDBFailures();

    return EXIT_SUCCESS;
}

Definition at line 43 of file persistentMap.h.

Constructor & Destructor Documentation

LUNCHBOX_API lunchbox::PersistentMap::PersistentMap

(

const std::string &

uri = std::string()

)

Construct a new persistent map.

Depending on the URI scheme an implementation backend is chosen. If no URI is given, a default one is selected. Available implementations are:

• leveldb://path (if LUNCHBOX_USE_LEVELDB is defined)
• skv://path_to_config#pdsname (if LUNCHBOX_USE_SKV is defined)

Parameters

uri	the storage backend and destination.

Exceptions

std::runtime_error	if no suitable implementation is found.
std::runtime_error	if opening the leveldb failed.

Version

1.9.2

LUNCHBOX_API lunchbox::PersistentMap::PersistentMap ( const URI &  uri )

explicit

Construct a persistent map using an URI.

See other ctor for details.

Version

1.9.2

LUNCHBOX_API lunchbox::PersistentMap::~PersistentMap

(

)

Destruct the persistent map.

Version

1.9.2

Member Function Documentation

LUNCHBOX_API bool lunchbox::PersistentMap::contains

(

const std::string &

key

)

const

Returns

true if the key exists.

Version

1.9.2

template<class V >

std::set< V > lunchbox::PersistentMap::getSet ( const std::string &  key )

inline

Retrieve a value as a set for a key.

Parameters

key	the key to retreive.

Returns

the values, or an empty set if the key is not available.

Version

1.9.2

Definition at line 194 of file persistentMap.h.

template<class V >

std::vector< V > lunchbox::PersistentMap::getVector ( const std::string &  key )

inline

Retrieve a value as a vector for a key.

Parameters

key	the key to retreive.

Returns

the values, or an empty vector if the key is not available.

Version

1.9.2

Definition at line 186 of file persistentMap.h.

static LUNCHBOX_API bool lunchbox::PersistentMap::handles ( const URI &  uri )

static

Returns

true if an implementation for the given URI is available.

Version

1.9.2

template<class V >

bool lunchbox::PersistentMap::insert ( const std::string &  key, const V &  value  )

inline

Insert or update a value in the database.

Parameters

key	the key to store the value.
value	the value stored at the key.

Returns

true on success, false otherwise

Exceptions

std::runtime_error

if the value is not copyable

Version

1.9.2

Definition at line 85 of file persistentMap.h.

Referenced by insert().

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template<class V >

bool lunchbox::PersistentMap::insert ( const std::string &  key, const std::vector< V > &  values  )

inline

Insert or update a vector of values in the database.

Parameters

key	the key to store the value.
value	the values stored at the key.

Returns

true on success, false otherwise

Exceptions

std::runtime_error

if the vector values are not copyable

Version

1.9.2

Definition at line 98 of file persistentMap.h.

template<class V >

bool lunchbox::PersistentMap::insert ( const std::string &  key, const std::set< V > &  values  )

inline

Insert or update a set of values in the database.

Parameters

key	the key to store the value.
value	the values stored at the key.

Returns

true on success, false otherwise

Exceptions

std::runtime_error

if the set values are not copyable

Version

1.9.2

Definition at line 111 of file persistentMap.h.

References insert().

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LUNCHBOX_API std::string lunchbox::PersistentMap::operator[]

(

const std::string &

key

)

const

Retrieve a value for a key.

Parameters

key	the key to retreive.

Returns

the value, or an empty string if the key is not available.

Version

1.9.2

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The documentation for this class was generated from the following file:

• persistentMap.h