本文整理汇总了C++中CnxPool_ptr类的典型用法代码示例。如果您正苦于以下问题：C++ CnxPool_ptr类的具体用法？C++ CnxPool_ptr怎么用？C++ CnxPool_ptr使用的例子？那么, 这里精选的类代码示例或许可以为您提供帮助。
在下文中一共展示了CnxPool_ptr类的10个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1:
postgis_datasource::~postgis_datasource()
{
if (! persist_connection_)
{
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (conn)
{
conn->close();
}
}
}
}示例2: catch
postgis_datasource::~postgis_datasource()
{
if (! persist_connection_)
{
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
try {
shared_ptr<Connection> conn = pool->borrowObject();
if (conn)
{
conn->close();
}
} catch (mapnik::datasource_exception const& ex) {
// happens when borrowObject tries to
// create a new connection and fails.
// In turn, new connection would be needed
// when our broke and was thus no good to
// be borrowed
// See https://github.com/mapnik/mapnik/issues/2191
}
}
}
}示例3: datasource_exception
box2d<double> postgis_datasource::envelope() const
{
if (extent_initialized_)
{
return extent_;
}
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return extent_;
if (conn->isOK())
{
std::ostringstream s;
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_)
{
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";
}
}
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
{
MAPNIK_LOG_DEBUG(postgis) << "postgis_datasource: Could not determine extent from query: " << s.str();
}
}
rs->close();
}
}
return extent_;
}示例4: __stats__
featureset_ptr postgis_datasource::features_at_point(coord2d const& pt, double tol) const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "postgis_datasource::features_at_point");
#endif
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return featureset_ptr();
if (conn->isOK())
{
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 = std::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 - tol, pt.y - tol, pt.x + tol, pt.y + tol);
std::string table_with_bbox = populate_tokens(table_, FMAX, box, 0, 0, mapnik::attributes());
s << " FROM " << table_with_bbox;
if (row_limit_ > 0)
{
s << " LIMIT " << row_limit_;
}
std::shared_ptr<IResultSet> rs = get_resultset(conn, s.str(), pool);
return std::make_shared<postgis_featureset>(rs, ctx, desc_.get_encoding(), !key_field_.empty());
}
}
return featureset_ptr();
}示例5: datasource
postgis_datasource::postgis_datasource(parameters const& params)
: datasource(params),
table_(*params.get<std::string>("table", "")),
schema_(""),
geometry_table_(*params.get<std::string>("geometry_table", "")),
geometry_field_(*params.get<std::string>("geometry_field", "")),
key_field_(*params.get<std::string>("key_field", "")),
cursor_fetch_size_(*params.get<mapnik::value_integer>("cursor_size", 0)),
row_limit_(*params.get<mapnik::value_integer>("row_limit", 0)),
type_(datasource::Vector),
srid_(*params.get<mapnik::value_integer>("srid", 0)),
extent_initialized_(false),
simplify_geometries_(false),
desc_(postgis_datasource::name(), "utf-8"),
creator_(params.get<std::string>("host"),
params.get<std::string>("port"),
params.get<std::string>("dbname"),
params.get<std::string>("user"),
params.get<std::string>("password"),
params.get<std::string>("connect_timeout", "4")),
bbox_token_("!bbox!"),
scale_denom_token_("!scale_denominator!"),
pixel_width_token_("!pixel_width!"),
pixel_height_token_("!pixel_height!"),
pool_max_size_(*params_.get<mapnik::value_integer>("max_size", 10)),
persist_connection_(*params.get<mapnik::boolean_type>("persist_connection", true)),
extent_from_subquery_(*params.get<mapnik::boolean_type>("extent_from_subquery", false)),
max_async_connections_(*params_.get<mapnik::value_integer>("max_async_connection", 1)),
asynchronous_request_(false),
// TODO - use for known tokens too: "(@\\w+|!\\w+!)"
pattern_(boost::regex("(@\\w+)",boost::regex::normal | boost::regbase::icase)),
// params below are for testing purposes only and may be removed at any time
intersect_min_scale_(*params.get<mapnik::value_integer>("intersect_min_scale", 0)),
intersect_max_scale_(*params.get<mapnik::value_integer>("intersect_max_scale", 0))
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "postgis_datasource::init");
#endif
if (table_.empty())
{
throw mapnik::datasource_exception("Postgis Plugin: missing <table> parameter");
}
boost::optional<std::string> ext = params.get<std::string>("extent");
if (ext && !ext->empty())
{
extent_initialized_ = extent_.from_string(*ext);
}
// NOTE: In multithread environment, pool_max_size_ should be
// max_async_connections_ * num_threads
if(max_async_connections_ > 1)
{
if(max_async_connections_ > pool_max_size_)
{
std::ostringstream err;
err << "PostGIS Plugin: Error: 'max_async_connections ("
<< max_async_connections_ << ") must be <= max_size(" << pool_max_size_ << ")";
throw mapnik::datasource_exception(err.str());
}
asynchronous_request_ = true;
}
boost::optional<mapnik::value_integer> initial_size = params.get<mapnik::value_integer>("initial_size", 1);
boost::optional<mapnik::boolean_type> autodetect_key_field = params.get<mapnik::boolean_type>("autodetect_key_field", false);
boost::optional<mapnik::boolean_type> estimate_extent = params.get<mapnik::boolean_type>("estimate_extent", false);
estimate_extent_ = estimate_extent && *estimate_extent;
boost::optional<mapnik::boolean_type> simplify_opt = params.get<mapnik::boolean_type>("simplify_geometries", false);
simplify_geometries_ = simplify_opt && *simplify_opt;
ConnectionManager::instance().registerPool(creator_, *initial_size, pool_max_size_);
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return;
if (conn->isOK())
{
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);
}
// NOTE: geometry_table_ how should ideally be a table name, but
// there are known edge cases where this will break down and
//.........这里部分代码省略.........
示例6: if
boost::optional<mapnik::datasource::geometry_t> postgis_datasource::get_geometry_type() const
{
boost::optional<mapnik::datasource::geometry_t> result;
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return result;
if (conn->isOK())
{
std::ostringstream s;
std::string g_type;
try
{
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
{
g_type = "";
}
}
}
catch (mapnik::datasource_exception const& ex) {
// let this pass on query error and use the fallback below
MAPNIK_LOG_WARN(postgis) << "postgis_datasource: metadata query failed: " << ex.what();
}
// 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);
}
else if (boost::algorithm::icontains(data, "polygon"))
{
g_type = "polygon";
result.reset(mapnik::datasource::Polygon);
}
//.........这里部分代码省略.........
示例7: __stats__
featureset_ptr pgraster_datasource::features_with_context(query const& q,processor_context_ptr proc_ctx) const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "pgraster_datasource::features_with_context");
#endif
box2d<double> const& box = q.get_bbox();
double scale_denom = q.scale_denominator();
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn;
if ( asynchronous_request_ )
{
// limit use to num_async_request_ => if reached don't borrow the last connexion object
std::shared_ptr<postgis_processor_context> pgis_ctxt = std::static_pointer_cast<postgis_processor_context>(proc_ctx);
if ( pgis_ctxt->num_async_requests_ < max_async_connections_ )
{
conn = pool->borrowObject();
pgis_ctxt->num_async_requests_++;
}
}
else
{
// Always get a connection in synchronous mode
conn = pool->borrowObject();
if(!conn )
{
throw mapnik::datasource_exception("Pgraster Plugin: Null connection");
}
}
if (geometryColumn_.empty())
{
std::ostringstream s_error;
s_error << "PostGIS: geometry name lookup failed for table '";
if (! schema_.empty())
{
s_error << schema_ << ".";
}
s_error << raster_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 << raster_table_ << "'.";
throw mapnik::datasource_exception(s_error.str());
}
const double px_gw = 1.0 / std::get<0>(q.resolution());
const double px_gh = 1.0 / std::get<1>(q.resolution());
MAPNIK_LOG_DEBUG(pgraster) << "pgraster_datasource: px_gw=" << px_gw
<< " px_gh=" << px_gh;
std::string table_with_bbox;
std::string col = geometryColumn_;
if ( use_overviews_ && !overviews_.empty()) {
std::string sch = overviews_[0].schema;
std::string tab = overviews_[0].table;
col = overviews_[0].column;
const double scale = std::min(px_gw, px_gh);
std::vector<pgraster_overview>::const_reverse_iterator i;
for (i=overviews_.rbegin(); i!=overviews_.rend(); ++i) {
const pgraster_overview& o = *i;
if ( o.scale < scale ) {
sch = o.schema;
tab = o.table;
col = o.column;
MAPNIK_LOG_DEBUG(pgraster)
<< "pgraster_datasource: using overview "
<< o.schema << "." << o.table << "." << o.column
<< " with scale=" << o.scale
<< " for min out scale=" << scale;
break;
} else {
MAPNIK_LOG_DEBUG(pgraster)
<< "pgraster_datasource: overview "
<< o.schema << "." << o.table << "." << o.column
<< " with scale=" << o.scale
<< " not good for min out scale " << scale;
}
}
table_with_bbox = table_; // possibly a subquery
boost::algorithm::replace_all(table_with_bbox,
mapnik::sql_utils::unquote_double(raster_table_), tab);
boost::algorithm::replace_all(table_with_bbox,
mapnik::sql_utils::unquote_double(schema_), sch);
//.........这里部分代码省略.........
示例8: datasource
pgraster_datasource::pgraster_datasource(parameters const& params)
: datasource(params),
table_(*params.get<std::string>("table", "")),
schema_(""),
raster_table_(*params.get<std::string>("raster_table", "")),
raster_field_(*params.get<std::string>("raster_field", "")),
key_field_(*params.get<std::string>("key_field", "")),
cursor_fetch_size_(*params.get<mapnik::value_integer>("cursor_size", 0)),
row_limit_(*params.get<value_integer>("row_limit", 0)),
type_(datasource::Raster),
srid_(*params.get<value_integer>("srid", 0)),
band_(*params.get<value_integer>("band", 0)),
extent_initialized_(false),
prescale_rasters_(*params.get<mapnik::boolean_type>("prescale_rasters", false)),
use_overviews_(*params.get<mapnik::boolean_type>("use_overviews", false)),
clip_rasters_(*params.get<mapnik::boolean_type>("clip_rasters", false)),
desc_(*params.get<std::string>("type"), "utf-8"),
creator_(params.get<std::string>("host"),
params.get<std::string>("port"),
params.get<std::string>("dbname"),
params.get<std::string>("user"),
params.get<std::string>("password"),
params.get<std::string>("connect_timeout", "4")),
bbox_token_("!bbox!"),
scale_denom_token_("!scale_denominator!"),
pixel_width_token_("!pixel_width!"),
pixel_height_token_("!pixel_height!"),
pool_max_size_(*params_.get<value_integer>("max_size", 10)),
persist_connection_(*params.get<mapnik::boolean_type>("persist_connection", true)),
extent_from_subquery_(*params.get<mapnik::boolean_type>("extent_from_subquery", false)),
estimate_extent_(*params.get<mapnik::boolean_type>("estimate_extent", false)),
max_async_connections_(*params_.get<value_integer>("max_async_connection", 1)),
asynchronous_request_(false),
// params below are for testing purposes only and may be removed at any time
intersect_min_scale_(*params.get<value_integer>("intersect_min_scale", 0)),
intersect_max_scale_(*params.get<value_integer>("intersect_max_scale", 0))
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "pgraster_datasource::init");
#endif
if (table_.empty())
{
throw mapnik::datasource_exception("Pgraster Plugin: missing <table> parameter");
}
boost::optional<std::string> ext = params.get<std::string>("extent");
if (ext && !ext->empty())
{
extent_initialized_ = extent_.from_string(*ext);
}
// NOTE: In multithread environment, pool_max_size_ should be
// max_async_connections_ * num_threads
if(max_async_connections_ > 1)
{
if(max_async_connections_ > pool_max_size_)
{
std::ostringstream err;
err << "PostGIS Plugin: Error: 'max_async_connections ("
<< max_async_connections_ << ") must be <= max_size(" << pool_max_size_ << ")";
throw mapnik::datasource_exception(err.str());
}
asynchronous_request_ = true;
}
boost::optional<value_integer> initial_size = params.get<value_integer>("initial_size", 1);
boost::optional<mapnik::boolean_type> autodetect_key_field = params.get<mapnik::boolean_type>("autodetect_key_field", false);
ConnectionManager::instance().registerPool(creator_, *initial_size, pool_max_size_);
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return;
if (conn->isOK())
{
desc_.set_encoding(conn->client_encoding());
if (raster_table_.empty())
{
raster_table_ = mapnik::sql_utils::table_from_sql(table_);
// non-trivial subqueries (having no FROM) make it
// impossible to use overviews
// TODO: improve "table_from_sql" ?
if ( raster_table_[raster_table_.find_first_not_of(" \t\r\n")] == '(' )
{
raster_table_.clear();
if ( use_overviews_ )
{
std::ostringstream err;
err << "Pgraster Plugin: overviews cannot be used "
"with non-trivial subqueries";
MAPNIK_LOG_WARN(pgraster) << err.str();
use_overviews_ = false;
}
if ( ! extent_from_subquery_ ) {
std::ostringstream err;
err << "Pgraster Plugin: extent can only be computed "
//.........这里部分代码省略.........
示例9: datasource_exception
box2d<double> pgraster_datasource::envelope() const
{
if (extent_initialized_)
{
return extent_;
}
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn = pool->borrowObject();
if (!conn) return extent_;
if (conn->isOK())
{
std::ostringstream s;
std::string col = mapnik::sql_utils::unquote_double(geometryColumn_);
std::string sch = mapnik::sql_utils::unquote_double(schema_);
std::string tab = mapnik::sql_utils::unquote_double(raster_table_);
if ( ! overviews_.empty() )
{
// query from highest-factor overview instead
const pgraster_overview& o = overviews_.back();
sch = o.schema;
tab = o.table;
col = o.column;
}
if (col.empty())
{
std::ostringstream s_error;
s_error << "PostGIS: unable to query the layer extent of table '";
if (! sch.empty())
{
s_error << sch << ".";
}
s_error << raster_table_ << "' because we cannot determine the raster field name."
<< "\nPlease provide either an 'extent' parameter to skip this query, "
<< "a 'raster_field' and/or 'raster_table' parameter, or add "
<< "standard constraints to your raster table.";
throw mapnik::datasource_exception("Pgraster Plugin: " + s_error.str());
}
if (estimate_extent_)
{
if (tab.empty())
{
std::ostringstream s_error;
s_error << "PostGIS: unable to query the layer extent as "
<< "we couldn't determine the raster table name.\n"
<< "Please provide either an 'extent' parameter to skip this query, "
<< "a 'raster_table' parameter, or do not set 'estimate_extent'";
throw mapnik::datasource_exception("Pgraster Plugin: " + s_error.str());
}
s << "SELECT ST_XMin(ext),ST_YMin(ext),ST_XMax(ext),ST_YMax(ext)"
<< " FROM (SELECT ST_Estimated_Extent('";
if (! sch.empty())
{
s << mapnik::sql_utils::unquote_double(sch) << "','";
}
s << mapnik::sql_utils::unquote_double(tab) << "','"
<< mapnik::sql_utils::unquote_double(col) << "') as ext) as tmp";
}
else
{
s << "SELECT ST_XMin(ext),ST_YMin(ext),ST_XMax(ext),ST_YMax(ext)"
<< " FROM (SELECT ST_Extent(" << quote_ident(col) << "::geometry) 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 tmpx";
}
else
{
if (! sch.empty())
{
s << quote_ident(sch) << ".";
}
// but if the subquery does not limit records then querying the
// actual table will be faster as indexes can be used
s << quote_ident(tab) << ") as tmp";
}
}
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))
//.........这里部分代码省略.........
示例10: __stats__
featureset_ptr postgis_datasource::features_with_context(query const& q,processor_context_ptr proc_ctx) const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "postgis_datasource::features_with_context");
#endif
box2d<double> const& box = q.get_bbox();
double scale_denom = q.scale_denominator();
CnxPool_ptr pool = ConnectionManager::instance().getPool(creator_.id());
if (pool)
{
shared_ptr<Connection> conn;
if ( asynchronous_request_ )
{
// limit use to num_async_request_ => if reached don't borrow the last connexion object
std::shared_ptr<postgis_processor_context> pgis_ctxt = std::static_pointer_cast<postgis_processor_context>(proc_ctx);
if ( pgis_ctxt->num_async_requests_ < max_async_connections_ )
{
conn = pool->borrowObject();
pgis_ctxt->num_async_requests_++;
}
}
else
{
// Always get a connection in synchronous mode
conn = pool->borrowObject();
if(!conn )
{
throw mapnik::datasource_exception("Postgis Plugin: Null connection");
}
}
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;
const double px_gw = 1.0 / std::get<0>(q.resolution());
const double px_gh = 1.0 / std::get<1>(q.resolution());
const double px_sz = std::min(px_gw, px_gh);
if (twkb_encoding_)
{
// This will only work against PostGIS 2.2, or a back-patched version
// that has (a) a ST_Simplify with a "preserve collapsed" flag and
// (b) a ST_RemoveRepeatedPoints with a tolerance parameter and
// (c) a ST_AsTWKB implementation
// What number of decimals of rounding does the pixel size imply?
const int twkb_rounding = -1 * std::lround(log10(px_sz) + twkb_rounding_adjustment_) + 1;
// And what's that in map units?
const double twkb_tolerance = pow(10.0, -1.0 * twkb_rounding);
s << "SELECT ST_AsTWKB(";
s << "ST_Simplify(";
s << "ST_RemoveRepeatedPoints(";
if (simplify_clip_resolution_ > 0.0 && simplify_clip_resolution_ > px_sz)
{
s << "ST_ClipByBox2D(";
}
s << "\"" << geometryColumn_ << "\"";
// ! ST_ClipByBox2D()
if (simplify_clip_resolution_ > 0.0 && simplify_clip_resolution_ > px_sz)
{
s << "," << sql_bbox(box) << ")";
}
// ! ST_RemoveRepeatedPoints()
s << "," << twkb_tolerance << ")";
// ! ST_Simplify(), with parameter to keep collapsed geometries
s << "," << twkb_tolerance << ",true)";
// ! ST_TWKB()
s << "," << twkb_rounding << ") AS geom";
//.........这里部分代码省略.........