C++ ConnectionManager::getPool方法代码示例

postgis_datasource::~postgis_datasource()
{
    if (is_bound_ && ! persist_connection_)
    {
        ConnectionManager* mgr = ConnectionManager::instance();
        shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
        if (pool)
        {
            shared_ptr<Connection> conn = pool->borrowObject();
            if (conn)
            {
                conn->close();
            }
        }
    }
}

boost::optional<mapnik::datasource::geometry_t> postgis_datasource::get_geometry_type() const
{
    if (! is_bound_)
    {
        bind();
    }

    boost::optional<mapnik::datasource::geometry_t> result;

    ConnectionManager* mgr = ConnectionManager::instance();
    shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
    if (pool)
    {
        shared_ptr<Connection> conn = pool->borrowObject();
        if (conn && conn->isOK())
        {
            PoolGuard<shared_ptr<Connection>, shared_ptr< Pool<Connection,ConnectionCreator> > > guard(conn, pool);

            std::ostringstream s;
            std::string g_type;

            s << "SELECT lower(type) as type FROM "
              << GEOMETRY_COLUMNS <<" WHERE f_table_name='"
              << mapnik::sql_utils::unquote_double(geometry_table_)
              << "'";

            if (! schema_.empty())
            {
                s << " AND f_table_schema='"
                  << mapnik::sql_utils::unquote_double(schema_)
                  << "'";
            }

            if (! geometry_field_.empty())
            {
                s << " AND f_geometry_column='"
                  << mapnik::sql_utils::unquote_double(geometry_field_)
                  << "'";
            }

            shared_ptr<ResultSet> rs = conn->executeQuery(s.str());
            if (rs->next())
            {
                g_type = rs->getValue("type");
                if (boost::algorithm::contains(g_type, "line"))
                {
                    result.reset(mapnik::datasource::LineString);
                    return result;
                }
                else if (boost::algorithm::contains(g_type, "point"))
                {
                    result.reset(mapnik::datasource::Point);
                    return result;
                }
                else if (boost::algorithm::contains(g_type, "polygon"))
                {
                    result.reset(mapnik::datasource::Polygon);
                    return result;
                }
                else // geometry
                {
                    result.reset(mapnik::datasource::Collection);
                    return result;
                }
            }

            // fallback to querying first several features
            if (g_type.empty() && ! geometryColumn_.empty())
            {
                s.str("");

                std::string prev_type("");

                s << "SELECT ST_GeometryType(\""
                  << geometryColumn_ << "\") AS geom"
                  << " FROM " << populate_tokens(table_);

                if (row_limit_ > 0 && row_limit_ < 5)
                {
                    s << " LIMIT " << row_limit_;
                }
                else
                {
                    s << " LIMIT 5";
                }

                shared_ptr<ResultSet> rs = conn->executeQuery(s.str());
                while (rs->next() && ! rs->isNull(0))
                {
                    const char* data = rs->getValue(0);
                    if (boost::algorithm::icontains(data, "line"))
                    {
                        g_type = "linestring";
                        result.reset(mapnik::datasource::LineString);
                    }
                    else if (boost::algorithm::icontains(data, "point"))
                    {
                        g_type = "point";
                        result.reset(mapnik::datasource::Point);
                    }
//.........这里部分代码省略.........

box2d<double> postgis_datasource::envelope() const
{
    if (extent_initialized_)
    {
        return extent_;
    }

    if (! is_bound_)
    {
        bind();
    }

    ConnectionManager* mgr = ConnectionManager::instance();
    shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
    if (pool)
    {
        shared_ptr<Connection> conn = pool->borrowObject();
        if (conn && conn->isOK())
        {
            PoolGuard<shared_ptr<Connection>, shared_ptr< Pool<Connection,ConnectionCreator> > > guard(conn, pool);

            std::ostringstream s;

            boost::optional<mapnik::boolean> estimate_extent =
                params_.get<mapnik::boolean>("estimate_extent", false);

            if (geometryColumn_.empty())
            {
                std::ostringstream s_error;
                s_error << "PostGIS: unable to query the layer extent of table '";

                if (! schema_.empty())
                {
                    s_error << schema_ << ".";
                }
                s_error << geometry_table_ << "' because we cannot determine the geometry field name."
                        << "\nPlease provide either an 'extent' parameter to skip this query, "
                        << "a 'geometry_field' and/or 'geometry_table' parameter, or add a "
                        << "record to the 'geometry_columns' for your table.";

                throw mapnik::datasource_exception("Postgis Plugin: " + s_error.str());
            }

            if (estimate_extent && *estimate_extent)
            {
                s << "SELECT ST_XMin(ext),ST_YMin(ext),ST_XMax(ext),ST_YMax(ext)"
                  << " FROM (SELECT ST_Estimated_Extent('";

                if (! schema_.empty())
                {
                    s << mapnik::sql_utils::unquote_double(schema_) << "','";
                }

                s << mapnik::sql_utils::unquote_double(geometry_table_) << "','"
                  << mapnik::sql_utils::unquote_double(geometryColumn_) << "') as ext) as tmp";
            }
            else
            {
                s << "SELECT ST_XMin(ext),ST_YMin(ext),ST_XMax(ext),ST_YMax(ext)"
                  << " FROM (SELECT ST_Extent(" <<geometryColumn_<< ") as ext from ";

                if (extent_from_subquery_)
                {
                    // if a subselect limits records then calculating the extent upon the
                    // subquery will be faster and the bounds will be more accurate
                    s << populate_tokens(table_) << ") as tmp";
                }
                else
                {
                    if (! schema_.empty())
                    {
                        s << schema_ << ".";
                    }

                    // but if the subquery does not limit records then querying the
                    // actual table will be faster as indexes can be used
                    s << geometry_table_ << ") as tmp";
                }
            }

            /*
              if (show_queries_)
              {
              std::clog << boost::format("PostGIS: sending query: %s\n") % s.str();
              }
            */

            shared_ptr<ResultSet> rs = conn->executeQuery(s.str());
            if (rs->next() && ! rs->isNull(0))
            {
                double lox, loy, hix, hiy;
                if (mapnik::util::string2double(rs->getValue(0), lox) &&
                    mapnik::util::string2double(rs->getValue(1), loy) &&
                    mapnik::util::string2double(rs->getValue(2), hix) &&
                    mapnik::util::string2double(rs->getValue(3), hiy))
                {
                    extent_.init(lox, loy, hix, hiy);
                    extent_initialized_ = true;
                }
                else
//.........这里部分代码省略.........

featureset_ptr postgis_datasource::features_at_point(coord2d const& pt) const
{
    if (! is_bound_)
    {
        bind();
    }

    ConnectionManager* mgr = ConnectionManager::instance();
    shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
    if (pool)
    {
        shared_ptr<Connection> conn = pool->borrowObject();
        if (conn && conn->isOK())
        {
            PoolGuard<shared_ptr<Connection>, shared_ptr< Pool<Connection,ConnectionCreator> > > guard(conn, pool);

            if (geometryColumn_.empty())
            {
                std::ostringstream s_error;
                s_error << "PostGIS: geometry name lookup failed for table '";

                if (! schema_.empty())
                {
                    s_error << schema_ << ".";
                }
                s_error << geometry_table_
                        << "'. Please manually provide the 'geometry_field' parameter or add an entry "
                        << "in the geometry_columns for '";

                if (! schema_.empty())
                {
                    s_error << schema_ << ".";
                }
                s_error << geometry_table_ << "'.";

                throw mapnik::datasource_exception(s_error.str());
            }

            std::ostringstream s;
            s << "SELECT ST_AsBinary(\"" << geometryColumn_ << "\") AS geom";

            mapnik::context_ptr ctx = boost::make_shared<mapnik::context_type>();
            std::vector<attribute_descriptor>::const_iterator itr = desc_.get_descriptors().begin();
            std::vector<attribute_descriptor>::const_iterator end = desc_.get_descriptors().end();

            if (! key_field_.empty())
            {
                mapnik::sql_utils::quote_attr(s, key_field_);
                ctx->push(key_field_);
                for (; itr != end; ++itr)
                {
                    if (itr->get_name() != key_field_)
                    {
                        mapnik::sql_utils::quote_attr(s, itr->get_name());
                        ctx->push(itr->get_name());
                    }
                }
            }
            else
            {
                for (; itr != end; ++itr)
                {
                    mapnik::sql_utils::quote_attr(s, itr->get_name());
                    ctx->push(itr->get_name());
                }
            }

            box2d<double> box(pt.x, pt.y, pt.x, pt.y);
            std::string table_with_bbox = populate_tokens(table_, FMAX, box);

            s << " FROM " << table_with_bbox;

            if (row_limit_ > 0)
            {
                s << " LIMIT " << row_limit_;
            }

            boost::shared_ptr<IResultSet> rs = get_resultset(conn, s.str());
            return boost::make_shared<postgis_featureset>(rs, ctx, desc_.get_encoding(), !key_field_.empty());
        }
    }

    return featureset_ptr();
}

featureset_ptr postgis_datasource::features(const query& q) const
{
    if (! is_bound_)
    {
        bind();
    }

    box2d<double> const& box = q.get_bbox();
    double scale_denom = q.scale_denominator();

    ConnectionManager* mgr = ConnectionManager::instance();
    shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
    if (pool)
    {
        shared_ptr<Connection> conn = pool->borrowObject();
        if (conn && conn->isOK())
        {
            PoolGuard<shared_ptr<Connection>, shared_ptr< Pool<Connection,ConnectionCreator> > > guard(conn ,pool);

            if (geometryColumn_.empty())
            {
                std::ostringstream s_error;
                s_error << "PostGIS: geometry name lookup failed for table '";

                if (! schema_.empty())
                {
                    s_error << schema_ << ".";
                }
                s_error << geometry_table_
                        << "'. Please manually provide the 'geometry_field' parameter or add an entry "
                        << "in the geometry_columns for '";

                if (! schema_.empty())
                {
                    s_error << schema_ << ".";
                }
                s_error << geometry_table_ << "'.";

                throw mapnik::datasource_exception(s_error.str());
            }

            std::ostringstream s;
            s << "SELECT ST_AsBinary(\"" << geometryColumn_ << "\") AS geom";

            mapnik::context_ptr ctx = boost::make_shared<mapnik::context_type>();
            std::set<std::string> const& props = q.property_names();
            std::set<std::string>::const_iterator pos = props.begin();
            std::set<std::string>::const_iterator end = props.end();

            if (! key_field_.empty())
            {
                mapnik::sql_utils::quote_attr(s, key_field_);
                ctx->push(key_field_);

                for (; pos != end; ++pos)
                {
                    if (*pos != key_field_)
                    {
                        mapnik::sql_utils::quote_attr(s, *pos);
                        ctx->push(*pos);
                    }
                }
            }
            else
            {
                for (; pos != end; ++pos)
                {
                    mapnik::sql_utils::quote_attr(s, *pos);
                    ctx->push(*pos);
                }
            }

            std::string table_with_bbox = populate_tokens(table_, scale_denom, box);

            s << " FROM " << table_with_bbox;

            if (row_limit_ > 0)
            {
                s << " LIMIT " << row_limit_;
            }

            boost::shared_ptr<IResultSet> rs = get_resultset(conn, s.str());
            return boost::make_shared<postgis_featureset>(rs, ctx, desc_.get_encoding(), !key_field_.empty());
        }
        else
        {
            throw mapnik::datasource_exception("Postgis Plugin: bad connection");
        }
    }

    return featureset_ptr();
}

void postgis_datasource::bind() const
{
    if (is_bound_)
    {
        return;
    }

    boost::optional<int> initial_size = params_.get<int>("initial_size", 1);
    boost::optional<int> max_size = params_.get<int>("max_size", 10);
    boost::optional<mapnik::boolean> autodetect_key_field = params_.get<mapnik::boolean>("autodetect_key_field", false);

    ConnectionManager* mgr = ConnectionManager::instance();
    mgr->registerPool(creator_, *initial_size, *max_size);

    shared_ptr< Pool<Connection,ConnectionCreator> > pool = mgr->getPool(creator_.id());
    if (pool)
    {
        shared_ptr<Connection> conn = pool->borrowObject();
        if (conn && conn->isOK())
        {
            PoolGuard<shared_ptr<Connection>,
                shared_ptr< Pool<Connection,ConnectionCreator> > > guard(conn, pool);

            desc_.set_encoding(conn->client_encoding());

            if (geometry_table_.empty())
            {
                geometry_table_ = mapnik::sql_utils::table_from_sql(table_);
            }

            std::string::size_type idx = geometry_table_.find_last_of('.');
            if (idx != std::string::npos)
            {
                schema_ = geometry_table_.substr(0, idx);
                geometry_table_ = geometry_table_.substr(idx + 1);
            }
            else
            {
                geometry_table_ = geometry_table_.substr(0);
            }

            // If we do not know both the geometry_field and the srid
            // then first attempt to fetch the geometry name from a geometry_columns entry.
            // This will return no records if we are querying a bogus table returned
            // from the simplistic table parsing in table_from_sql() or if
            // the table parameter references a table, view, or subselect not
            // registered in the geometry columns.
            geometryColumn_ = geometry_field_;
            if (geometryColumn_.empty() || srid_ == 0)
            {
                std::ostringstream s;
                s << "SELECT f_geometry_column, srid FROM "
                  << GEOMETRY_COLUMNS <<" WHERE f_table_name='"
                  << mapnik::sql_utils::unquote_double(geometry_table_)
                  << "'";

                if (! schema_.empty())
                {
                    s << " AND f_table_schema='"
                      << mapnik::sql_utils::unquote_double(schema_)
                      << "'";
                }

                if (! geometry_field_.empty())
                {
                    s << " AND f_geometry_column='"
                      << mapnik::sql_utils::unquote_double(geometry_field_)
                      << "'";
                }

                /*
                  if (show_queries_)
                  {
                  std::clog << boost::format("PostGIS: sending query: %s\n") % s.str();
                  }
                */

                shared_ptr<ResultSet> rs = conn->executeQuery(s.str());
                if (rs->next())
                {
                    geometryColumn_ = rs->getValue("f_geometry_column");

                    if (srid_ == 0)
                    {
                        const char* srid_c = rs->getValue("srid");
                        if (srid_c != NULL)
                        {
                            int result = 0;
                            if (mapnik::util::string2int(srid_c, result))
                            {
                                srid_ = result;
                            }
                        }
                    }
                }
                rs->close();

                // If we still do not know the srid then we can try to fetch
                // it from the 'table_' parameter, which should work even if it is
                // a subselect as long as we know the geometry_field to query
//.........这里部分代码省略.........