/***************************************************************************** * * This file is part of Mapnik (c++ mapping toolkit) * * Copyright (C) 2011 Artem Pavlenko * * This library is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * 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 St, Fifth Floor, Boston, MA 02110-1301 USA * *****************************************************************************/ #include "connection_manager.hpp" #include "postgis_datasource.hpp" #include "postgis_featureset.hpp" // mapnik #include <mapnik/debug.hpp> #include <mapnik/global.hpp> #include <mapnik/boolean.hpp> #include <mapnik/sql_utils.hpp> #include <mapnik/util/conversions.hpp> #include <mapnik/timer.hpp> #include <mapnik/value_types.hpp> // boost #include <boost/algorithm/string.hpp> #include <boost/tokenizer.hpp> #include <boost/format.hpp> #include <boost/make_shared.hpp> // stl #include <string> #include <algorithm> #include <set> #include <sstream> #include <iomanip> DATASOURCE_PLUGIN(postgis_datasource) const double postgis_datasource::FMAX = std::numeric_limits<double>::max(); const std::string postgis_datasource::GEOMETRY_COLUMNS = "geometry_columns"; const std::string postgis_datasource::SPATIAL_REF_SYS = "spatial_ref_system"; using boost::shared_ptr; using mapnik::attribute_descriptor; 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<int>("row_limit", 0)), type_(datasource::Vector), srid_(*params.get<int>("srid", 0)), extent_initialized_(false), simplify_geometries_(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!"), persist_connection_(*params.get<mapnik::boolean>("persist_connection", true)), extent_from_subquery_(*params.get<mapnik::boolean>("extent_from_subquery", false)), // params below are for testing purposes only (will likely be removed at any time) intersect_min_scale_(*params.get<int>("intersect_min_scale", 0)), intersect_max_scale_(*params.get<int>("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); } 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); boost::optional<mapnik::boolean> estimate_extent = params.get<mapnik::boolean>("estimate_extent", false); estimate_extent_ = estimate_extent && *estimate_extent; boost::optional<mapnik::boolean> simplify_opt = params.get<mapnik::boolean>("simplify_geometries", false); simplify_geometries_ = simplify_opt && *simplify_opt; ConnectionManager::instance().registerPool(creator_, *initial_size, *max_size); shared_ptr< Pool<Connection,ConnectionCreator> > 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); } // 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) { #ifdef MAPNIK_STATS mapnik::progress_timer __stats2__(std::clog, "postgis_datasource::init(get_srid_and_geometry_column)"); #endif std::ostringstream s; try { 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_) << "'"; } 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; const char * end = srid_c + std::strlen(srid_c); if (mapnik::util::string2int(srid_c, end, result)) { srid_ = result; } } } } rs->close(); } 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(); } // 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 if (! geometryColumn_.empty() && srid_ <= 0) { s.str(""); s << "SELECT ST_SRID(\"" << geometryColumn_ << "\") AS srid FROM " << populate_tokens(table_) << " WHERE \"" << geometryColumn_ << "\" IS NOT NULL LIMIT 1;"; shared_ptr<ResultSet> rs = conn->executeQuery(s.str()); if (rs->next()) { const char* srid_c = rs->getValue("srid"); if (srid_c != NULL) { int result = 0; const char * end = srid_c + std::strlen(srid_c); if (mapnik::util::string2int(srid_c, end, result)) { srid_ = result; } } } rs->close(); } } // detect primary key if (*autodetect_key_field && key_field_.empty()) { #ifdef MAPNIK_STATS mapnik::progress_timer __stats2__(std::clog, "postgis_datasource::bind(get_primary_key)"); #endif std::ostringstream s; s << "SELECT a.attname, a.attnum, t.typname, t.typname in ('int2','int4','int8') " "AS is_int FROM pg_class c, pg_attribute a, pg_type t, pg_namespace n, pg_index i " "WHERE a.attnum > 0 AND a.attrelid = c.oid " "AND a.atttypid = t.oid AND c.relnamespace = n.oid " "AND c.oid = i.indrelid AND i.indisprimary = 't' " "AND t.typname !~ '^geom' AND c.relname =" << " '" << mapnik::sql_utils::unquote_double(geometry_table_) << "' " //"AND a.attnum = ANY (i.indkey) " // postgres >= 8.1 << "AND (i.indkey[0]=a.attnum OR i.indkey[1]=a.attnum OR i.indkey[2]=a.attnum " "OR i.indkey[3]=a.attnum OR i.indkey[4]=a.attnum OR i.indkey[5]=a.attnum " "OR i.indkey[6]=a.attnum OR i.indkey[7]=a.attnum OR i.indkey[8]=a.attnum " "OR i.indkey[9]=a.attnum) "; if (! schema_.empty()) { s << "AND n.nspname='" << mapnik::sql_utils::unquote_double(schema_) << "' "; } s << "ORDER BY a.attnum"; shared_ptr<ResultSet> rs_key = conn->executeQuery(s.str()); if (rs_key->next()) { unsigned int result_rows = rs_key->size(); if (result_rows == 1) { bool is_int = (std::string(rs_key->getValue(3)) == "t"); if (is_int) { const char* key_field_string = rs_key->getValue(0); if (key_field_string) { key_field_ = std::string(key_field_string); MAPNIK_LOG_DEBUG(postgis) << "postgis_datasource: auto-detected key field of '" << key_field_ << "' on table '" << geometry_table_ << "'"; } } else { // throw for cases like a numeric primary key, which is invalid // as it should be floating point (int numerics are useless) std::ostringstream err; err << "PostGIS Plugin: Error: '" << rs_key->getValue(0) << "' on table '" << geometry_table_ << "' is not a valid integer primary key field\n"; throw mapnik::datasource_exception(err.str()); } } else if (result_rows > 1) { std::ostringstream err; err << "PostGIS Plugin: Error: '" << "multi column primary key detected but is not supported"; throw mapnik::datasource_exception(err.str()); } } rs_key->close(); } // if a globally unique key field/primary key is required // but still not known at this point, then throw if (*autodetect_key_field && key_field_.empty()) { throw mapnik::datasource_exception(std::string("PostGIS Plugin: Error: primary key required") + " but could not be detected for table '" + geometry_table_ + "', please supply 'key_field' option to specify field to use for primary key"); } if (srid_ == 0) { srid_ = -1; MAPNIK_LOG_DEBUG(postgis) << "postgis_datasource: Table " << table_ << " is using SRID=" << srid_; } // At this point the geometry_field may still not be known // but we'll catch that where more useful... MAPNIK_LOG_DEBUG(postgis) << "postgis_datasource: Using SRID=" << srid_; MAPNIK_LOG_DEBUG(postgis) << "postgis_datasource: Using geometry_column=" << geometryColumn_; // collect attribute desc #ifdef MAPNIK_STATS mapnik::progress_timer __stats2__(std::clog, "postgis_datasource::bind(get_column_description)"); #endif std::ostringstream s; s << "SELECT * FROM " << populate_tokens(table_) << " LIMIT 0"; shared_ptr<ResultSet> rs = conn->executeQuery(s.str()); int count = rs->getNumFields(); bool found_key_field = false; for (int i = 0; i < count; ++i) { std::string fld_name = rs->getFieldName(i); int type_oid = rs->getTypeOID(i); // validate type of key_field if (! found_key_field && ! key_field_.empty() && fld_name == key_field_) { if (type_oid == 20 || type_oid == 21 || type_oid == 23) { found_key_field = true; desc_.add_descriptor(attribute_descriptor(fld_name, mapnik::Integer)); } else { std::ostringstream error_s; error_s << "invalid type '"; std::ostringstream type_s; type_s << "SELECT oid, typname FROM pg_type WHERE oid = " << type_oid; shared_ptr<ResultSet> rs_oid = conn->executeQuery(type_s.str()); if (rs_oid->next()) { error_s << rs_oid->getValue("typname") << "' (oid:" << rs_oid->getValue("oid") << ")"; } else { error_s << "oid:" << type_oid << "'"; } rs_oid->close(); error_s << " for key_field '" << fld_name << "' - " << "must be an integer primary key"; rs->close(); throw mapnik::datasource_exception(error_s.str()); } } else { switch (type_oid) { case 16: // bool desc_.add_descriptor(attribute_descriptor(fld_name, mapnik::Boolean)); break; case 20: // int8 case 21: // int2 case 23: // int4 desc_.add_descriptor(attribute_descriptor(fld_name, mapnik::Integer)); break; case 700: // float4 case 701: // float8 case 1700: // numeric desc_.add_descriptor(attribute_descriptor(fld_name, mapnik::Double)); break; case 1042: // bpchar case 1043: // varchar case 25: // text case 705: // literal desc_.add_descriptor(attribute_descriptor(fld_name, mapnik::String)); break; default: // should not get here #ifdef MAPNIK_LOG s.str(""); s << "SELECT oid, typname FROM pg_type WHERE oid = " << type_oid; shared_ptr<ResultSet> rs_oid = conn->executeQuery(s.str()); if (rs_oid->next()) { std::string typname(rs_oid->getValue("typname")); if (typname != "geometry") { MAPNIK_LOG_WARN(postgis) << "postgis_datasource: Unknown type=" << typname << " (oid:" << rs_oid->getValue("oid") << ")"; } } else { MAPNIK_LOG_WARN(postgis) << "postgis_datasource: Unknown type_oid=" << type_oid; } rs_oid->close(); #endif break; } } } rs->close(); } } } postgis_datasource::~postgis_datasource() { if (! persist_connection_) { shared_ptr< Pool<Connection,ConnectionCreator> > pool = ConnectionManager::instance().getPool(creator_.id()); if (pool) { shared_ptr<Connection> conn = pool->borrowObject(); if (conn) { conn->close(); } } } } const char * postgis_datasource::name() { return "postgis"; } mapnik::datasource::datasource_t postgis_datasource::type() const { return type_; } layer_descriptor postgis_datasource::get_descriptor() const { return desc_; } std::string postgis_datasource::sql_bbox(box2d<double> const& env) const { std::ostringstream b; if (srid_ > 0) { b << "ST_SetSRID("; } b << "'BOX3D("; b << std::setprecision(16); b << env.minx() << " " << env.miny() << ","; b << env.maxx() << " " << env.maxy() << ")'::box3d"; if (srid_ > 0) { b << ", " << srid_ << ")"; } return b.str(); } std::string postgis_datasource::populate_tokens(std::string const& sql) const { std::string populated_sql = sql; if (boost::algorithm::icontains(sql, bbox_token_)) { box2d<double> max_env(-1.0 * FMAX, -1.0 * FMAX, FMAX, FMAX); const std::string max_box = sql_bbox(max_env); boost::algorithm::replace_all(populated_sql, bbox_token_, max_box); } if (boost::algorithm::icontains(sql, scale_denom_token_)) { std::ostringstream ss; ss << FMAX; boost::algorithm::replace_all(populated_sql, scale_denom_token_, ss.str()); } if (boost::algorithm::icontains(sql, pixel_width_token_)) { std::ostringstream ss; ss << 0; boost::algorithm::replace_all(populated_sql, pixel_width_token_, ss.str()); } if (boost::algorithm::icontains(sql, pixel_height_token_)) { std::ostringstream ss; ss << 0; boost::algorithm::replace_all(populated_sql, pixel_height_token_, ss.str()); } return populated_sql; } std::string postgis_datasource::populate_tokens(std::string const& sql, double scale_denom, box2d<double> const& env, double pixel_width, double pixel_height) const { std::string populated_sql = sql; std::string box = sql_bbox(env); if (boost::algorithm::icontains(populated_sql, scale_denom_token_)) { std::ostringstream ss; ss << scale_denom; boost::algorithm::replace_all(populated_sql, scale_denom_token_, ss.str()); } if (boost::algorithm::icontains(sql, pixel_width_token_)) { std::ostringstream ss; ss << pixel_width; boost::algorithm::replace_all(populated_sql, pixel_width_token_, ss.str()); } if (boost::algorithm::icontains(sql, pixel_height_token_)) { std::ostringstream ss; ss << pixel_height; boost::algorithm::replace_all(populated_sql, pixel_height_token_, ss.str()); } if (boost::algorithm::icontains(populated_sql, bbox_token_)) { boost::algorithm::replace_all(populated_sql, bbox_token_, box); return populated_sql; } else { std::ostringstream s; if (intersect_min_scale_ > 0 && (scale_denom <= intersect_min_scale_)) { s << " WHERE ST_Intersects(\"" << geometryColumn_ << "\"," << box << ")"; } else if (intersect_max_scale_ > 0 && (scale_denom >= intersect_max_scale_)) { // do no bbox restriction } else { s << " WHERE \"" << geometryColumn_ << "\" && " << box; } return populated_sql + s.str(); } } boost::shared_ptr<IResultSet> postgis_datasource::get_resultset(boost::shared_ptr<Connection> const &conn, std::string const& sql) const { if (cursor_fetch_size_ > 0) { // cursor std::ostringstream csql; std::string cursor_name = conn->new_cursor_name(); csql << "DECLARE " << cursor_name << " BINARY INSENSITIVE NO SCROLL CURSOR WITH HOLD FOR " << sql << " FOR READ ONLY"; if (! conn->execute(csql.str())) { // TODO - better error throw mapnik::datasource_exception("Postgis Plugin: error creating cursor for data select." ); } return boost::make_shared<CursorResultSet>(conn, cursor_name, cursor_fetch_size_); } else { // no cursor return conn->executeQuery(sql, 1); } } featureset_ptr postgis_datasource::features(const query& q) const { #ifdef MAPNIK_STATS mapnik::progress_timer __stats__(std::clog, "postgis_datasource::features"); #endif box2d<double> const& box = q.get_bbox(); double scale_denom = q.scale_denominator(); shared_ptr< Pool<Connection,ConnectionCreator> > pool = ConnectionManager::instance().getPool(creator_.id()); if (pool) { shared_ptr<Connection> conn = pool->borrowObject(); if (conn && 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; const double px_gw = 1.0 / boost::get<0>(q.resolution()); const double px_gh = 1.0 / boost::get<1>(q.resolution()); s << "SELECT ST_AsBinary("; if (simplify_geometries_) { s << "ST_Simplify("; } s << "\"" << geometryColumn_ << "\""; if (simplify_geometries_) { // 1/20 of pixel seems to be a good compromise to avoid // drop of collapsed polygons. // See https://github.com/mapnik/mapnik/issues/1639 const double tolerance = std::min(px_gw, px_gh) / 20.0; s << ", " << tolerance << ")"; } s << ") 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, px_gw, px_gh); 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 { std::string err_msg = "Postgis Plugin:"; if (conn) { err_msg += conn->status(); } else { err_msg += " Null connection"; } throw mapnik::datasource_exception(err_msg); } } return featureset_ptr(); } 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 shared_ptr< Pool<Connection,ConnectionCreator> > 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 = 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 - tol, pt.y - tol, pt.x + tol, pt.y + tol); std::string table_with_bbox = populate_tokens(table_, FMAX, box, 0, 0); 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(); } box2d<double> postgis_datasource::envelope() const { if (extent_initialized_) { return extent_; } shared_ptr< Pool<Connection,ConnectionCreator> > 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_; } boost::optional<mapnik::datasource::geometry_t> postgis_datasource::get_geometry_type() const { boost::optional<mapnik::datasource::geometry_t> result; shared_ptr< Pool<Connection,ConnectionCreator> > 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 { result.reset(mapnik::datasource::Collection); return result; } } } 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); } else // geometry { result.reset(mapnik::datasource::Collection); return result; } if (! prev_type.empty() && g_type != prev_type) { result.reset(mapnik::datasource::Collection); return result; } prev_type = g_type; } } } } return result; }