mapnik/plugins/input/sqlite/sqlite_datasource.cpp
2015-03-22 14:58:14 -07:00

636 lines
21 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2014 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 "sqlite_datasource.hpp"
#include "sqlite_featureset.hpp"
#include "sqlite_resultset.hpp"
#include "sqlite_utils.hpp"
// mapnik
#include <mapnik/debug.hpp>
#include <mapnik/boolean.hpp>
#include <mapnik/sql_utils.hpp>
#include <mapnik/util/geometry_to_ds_type.hpp>
#include <mapnik/timer.hpp>
#include <mapnik/wkb.hpp>
#include <mapnik/util/trim.hpp>
#include <mapnik/util/fs.hpp>
#include <mapnik/geometry_empty.hpp>
// boost
#include <boost/algorithm/string.hpp>
#include <boost/tokenizer.hpp>
using mapnik::box2d;
using mapnik::coord2d;
using mapnik::query;
using mapnik::featureset_ptr;
using mapnik::layer_descriptor;
using mapnik::attribute_descriptor;
using mapnik::datasource_exception;
using mapnik::datasource;
using mapnik::parameters;
DATASOURCE_PLUGIN(sqlite_datasource)
sqlite_datasource::sqlite_datasource(parameters const& params)
: datasource(params),
extent_(),
extent_initialized_(false),
type_(datasource::Vector),
table_(*params.get<std::string>("table", "")),
fields_(*params.get<std::string>("fields", "*")),
metadata_(*params.get<std::string>("metadata", "")),
geometry_table_(*params.get<std::string>("geometry_table", "")),
geometry_field_(*params.get<std::string>("geometry_field", "")),
index_table_(*params.get<std::string>("index_table", "")),
key_field_(*params.get<std::string>("key_field", "")),
row_offset_(*params.get<mapnik::value_integer>("row_offset", 0)),
row_limit_(*params.get<mapnik::value_integer>("row_limit", 0)),
intersects_token_("!intersects!"),
desc_(sqlite_datasource::name(), *params.get<std::string>("encoding", "utf-8")),
format_(mapnik::wkbAuto)
{
/* TODO
- throw if no primary key but spatial index is present?
- remove auto-indexing
- if spatialite - leverage more of the metadata for geometry type detection
*/
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "sqlite_datasource::init");
#endif
boost::optional<std::string> file = params.get<std::string>("file");
if (! file) throw datasource_exception("Sqlite Plugin: missing <file> parameter");
boost::optional<std::string> base = params.get<std::string>("base");
if (base)
dataset_name_ = *base + "/" + *file;
else
dataset_name_ = *file;
if ((dataset_name_.compare(":memory:") != 0) && (!mapnik::util::exists(dataset_name_)))
{
throw datasource_exception("Sqlite Plugin: " + dataset_name_ + " does not exist");
}
use_spatial_index_ = *params.get<mapnik::boolean_type>("use_spatial_index", true);
// TODO - remove this option once all datasources have an indexing api
bool auto_index = *params.get<mapnik::boolean_type>("auto_index", true);
boost::optional<std::string> ext = params.get<std::string>("extent");
if (ext) extent_initialized_ = extent_.from_string(*ext);
boost::optional<std::string> wkb = params.get<std::string>("wkb_format");
if (wkb)
{
if (*wkb == "spatialite")
{
format_ = mapnik::wkbSpatiaLite;
}
else if (*wkb == "generic")
{
format_ = mapnik::wkbGeneric;
}
else
{
format_ = mapnik::wkbAuto;
}
}
// Populate init_statements_
// 1. Build attach database statements from the "attachdb" parameter
// 2. Add explicit init statements from "initdb" parameter
// Note that we do some extra work to make sure that any attached
// databases are relative to directory containing dataset_name_. Sqlite
// will default to attaching from cwd. Typicaly usage means that the
// map loader will produce full paths here.
boost::optional<std::string> attachdb = params.get<std::string>("attachdb");
if (attachdb)
{
parse_attachdb(*attachdb);
}
boost::optional<std::string> initdb = params.get<std::string>("initdb");
if (initdb)
{
init_statements_.push_back(*initdb);
}
// now actually create the connection and start executing setup sql
dataset_ = std::make_shared<sqlite_connection>(dataset_name_);
boost::optional<mapnik::value_integer> table_by_index = params.get<mapnik::value_integer>("table_by_index");
int passed_parameters = 0;
passed_parameters += params.get<std::string>("table") ? 1 : 0;
passed_parameters += table_by_index ? 1 : 0;
if (passed_parameters > 1)
{
throw datasource_exception("SQLite Plugin: you can only select an by name "
"('table' parameter), by number ('table_by_index' parameter), "
"do not supply 2 or more of them at the same time" );
}
if (table_by_index)
{
std::vector<std::string> tables;
sqlite_utils::get_tables(dataset_,tables);
if (*table_by_index < 0 || *table_by_index >= static_cast<int>(tables.size()))
{
std::ostringstream s;
s << "SQLite Plugin: only "
<< tables.size()
<< " table(s) exist, cannot find table by index '" << *table_by_index << "'";
throw datasource_exception(s.str());
}
table_ = tables[*table_by_index];
}
if (table_.empty())
{
throw mapnik::datasource_exception("Sqlite Plugin: missing <table> parameter");
}
if (geometry_table_.empty())
{
geometry_table_ = mapnik::sql_utils::table_from_sql(table_);
}
// if 'table_' is a subquery then we try to deduce names
// and types from the first row returned from that query
using_subquery_ = false;
if (table_ != geometry_table_)
{
using_subquery_ = true;
}
else
{
// attempt to auto-quote table if needed
if (sqlite_utils::needs_quoting(table_))
{
table_ = std::string("[") + table_ + "]";
geometry_table_ = table_;
}
}
// Execute init_statements_
for (std::vector<std::string>::const_iterator iter = init_statements_.begin();
iter != init_statements_.end(); ++iter)
{
MAPNIK_LOG_DEBUG(sqlite) << "sqlite_datasource: Execute init sql=" << *iter;
dataset_->execute(*iter);
}
bool found_types_via_subquery = false;
if (using_subquery_)
{
std::ostringstream s;
std::string query = populate_tokens(table_);
s << "SELECT " << fields_ << " FROM (" << query << ") LIMIT 1";
found_types_via_subquery = sqlite_utils::detect_types_from_subquery(
s.str(),
geometry_field_,
desc_,
dataset_);
}
// TODO - consider removing this
if (key_field_ == "rowid")
{
desc_.add_descriptor(attribute_descriptor("rowid", mapnik::Integer));
}
bool found_table = sqlite_utils::table_info(key_field_,
found_types_via_subquery,
geometry_field_,
geometry_table_,
desc_,
dataset_);
if (! found_table)
{
std::ostringstream s;
s << "Sqlite Plugin: could not query table '" << geometry_table_ << "'";
if (using_subquery_)
{
s << " from subquery '" << table_ << "'";
}
// report get available tables
std::vector<std::string> tables;
sqlite_utils::get_tables(dataset_,tables);
if (tables.size() > 0)
{
s << " (available tables for " << dataset_name_ << " are: '" << boost::algorithm::join(tables, ", ") << "')";
}
throw datasource_exception(s.str());
}
if (geometry_field_.empty())
{
std::ostringstream s;
s << "Sqlite Plugin: unable to detect the column "
<< "containing a valid geometry on table '" << geometry_table_ << "'. "
<< "Please provide a column name by passing the 'geometry_field' option "
<< "or indicate a different spatial table to use by passing the 'geometry_table' option";
throw datasource_exception(s.str());
}
if (index_table_.empty())
{
// Generate implicit index_table name - need to do this after
// we have discovered meta-data or else we don't know the column name
index_table_ = sqlite_utils::index_for_table(geometry_table_,geometry_field_);
}
std::string index_db = sqlite_utils::index_for_db(dataset_name_);
has_spatial_index_ = false;
if (use_spatial_index_)
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats2__(std::clog, "sqlite_datasource::init(use_spatial_index)");
#endif
bool index_db_attached = false;
if (mapnik::util::exists(index_db))
{
dataset_->execute("attach database '" + index_db + "' as " + index_table_);
index_db_attached = true;
}
has_spatial_index_ = sqlite_utils::has_rtree(index_table_,dataset_);
if (!has_spatial_index_ && auto_index)
{
if (! key_field_.empty())
{
std::ostringstream query;
query << "SELECT "
<< geometry_field_
<< "," << key_field_
<< " FROM ("
<< geometry_table_ << ")";
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats2__(std::clog, "sqlite_datasource::init(create_spatial_index)");
#endif
std::shared_ptr<sqlite_resultset> rs = dataset_->execute_query(query.str());
if (sqlite_utils::create_spatial_index(index_db,index_table_,rs))
{
//extent_initialized_ = true;
has_spatial_index_ = true;
if (!index_db_attached && mapnik::util::exists(index_db))
{
dataset_->execute("attach database '" + index_db + "' as " + index_table_);
}
}
}
else
{
std::ostringstream s;
s << "Sqlite Plugin: could not generate spatial index"
<< " for table '" << geometry_table_ << "'"
<< " as no primary key can be detected."
<< " You should either declare an INTEGER PRIMARY KEY"
<< " or set the 'key_field' option to force a"
<< " given field to be used as the primary key";
throw datasource_exception(s.str());
}
}
}
if (! extent_initialized_)
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats2__(std::clog, "sqlite_datasource::init(detect_extent)");
#endif
// TODO - clean this up - reducing arguments
std::string query = populate_tokens(table_);
if (!sqlite_utils::detect_extent(dataset_,
has_spatial_index_,
extent_,
index_table_,
metadata_,
geometry_field_,
geometry_table_,
key_field_,
query))
{
std::ostringstream s;
s << "Sqlite Plugin: extent could not be determined for table '"
<< geometry_table_ << "' and geometry field '" << geometry_field_ << "'"
<< " because an rtree spatial index is missing or empty."
<< " - either set the table 'extent' or create an rtree spatial index";
throw datasource_exception(s.str());
}
}
}
std::string sqlite_datasource::populate_tokens(std::string const& sql) const
{
std::string populated_sql = sql;
if (boost::algorithm::ifind_first(populated_sql, intersects_token_))
{
// replace with dummy comparison that is true
boost::algorithm::ireplace_first(populated_sql, intersects_token_, "1=1");
}
return populated_sql;
}
sqlite_datasource::~sqlite_datasource()
{
}
void sqlite_datasource::parse_attachdb(std::string const& attachdb) const
{
boost::char_separator<char> sep(",");
boost::tokenizer<boost::char_separator<char> > tok(attachdb, sep);
// The attachdb line is a comma sparated list of [dbname@]filename
for (boost::tokenizer<boost::char_separator<char> >::iterator beg = tok.begin();
beg != tok.end(); ++beg)
{
std::string const& spec(*beg);
size_t atpos = spec.find('@');
// See if it contains an @ sign
if (atpos == spec.npos)
{
throw datasource_exception("attachdb parameter has syntax dbname@filename[,...]");
}
// Break out the dbname and the filename
std::string dbname = mapnik::util::trim_copy(spec.substr(0, atpos));
std::string filename = mapnik::util::trim_copy(spec.substr(atpos + 1));
// Normalize the filename and make it relative to dataset_name_
if (filename.compare(":memory:") != 0 && mapnik::util::is_relative(filename))
{
filename = mapnik::util::make_relative(filename,dataset_name_);
}
// And add an init_statement_
init_statements_.push_back("attach database '" + filename + "' as " + dbname);
}
}
const char * sqlite_datasource::name()
{
return "sqlite";
}
mapnik::datasource::datasource_t sqlite_datasource::type() const
{
return type_;
}
box2d<double> sqlite_datasource::envelope() const
{
return extent_;
}
boost::optional<mapnik::datasource::geometry_t> sqlite_datasource::get_geometry_type() const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "sqlite_datasource::get_geometry_type");
#endif
boost::optional<mapnik::datasource::geometry_t> result;
if (dataset_)
{
// get geometry type by querying first features
std::ostringstream s;
s << "SELECT " << geometry_field_
<< " FROM " << geometry_table_;
if (row_limit_ > 0 && row_limit_ < 5)
{
s << " LIMIT " << row_limit_;
}
else
{
s << " LIMIT 5";
}
std::shared_ptr<sqlite_resultset> rs = dataset_->execute_query(s.str());
int multi_type = 0;
while (rs->is_valid() && rs->step_next())
{
int size;
const char* data = (const char*) rs->column_blob(0, size);
if (data)
{
mapnik::new_geometry::geometry geom = mapnik::geometry_utils::from_wkb(data, size, format_);
if (mapnik::new_geometry::empty(geom))
{
continue;
}
mapnik::util::to_ds_type(geom,result);
if (result)
{
int type = static_cast<int>(*result);
if (multi_type > 0 && multi_type != type)
{
result.reset(mapnik::datasource::Collection);
return result;
}
multi_type = type;
}
}
}
}
return result;
}
layer_descriptor sqlite_datasource::get_descriptor() const
{
return desc_;
}
featureset_ptr sqlite_datasource::features(query const& q) const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "sqlite_datasource::features");
#endif
if (dataset_)
{
mapnik::box2d<double> const& e = q.get_bbox();
std::ostringstream s;
mapnik::context_ptr ctx = std::make_shared<mapnik::context_type>();
s << "SELECT " << geometry_field_;
if (!key_field_.empty())
{
s << "," << key_field_;
ctx->push(key_field_);
}
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();
for ( ;pos != end;++pos)
{
// TODO - should we restrict duplicate key query?
//if (*pos != key_field_)
s << ",[" << *pos << "]";
ctx->push(*pos);
}
s << " FROM ";
std::string query(table_);
if (! key_field_.empty() && has_spatial_index_)
{
// TODO - debug warn if fails
sqlite_utils::apply_spatial_filter(query,
e,
table_,
key_field_,
index_table_,
geometry_table_,
intersects_token_);
}
else
{
query = populate_tokens(table_);
}
s << query ;
if (row_limit_ > 0)
{
s << " LIMIT " << row_limit_;
}
if (row_offset_ > 0)
{
s << " OFFSET " << row_offset_;
}
MAPNIK_LOG_DEBUG(sqlite) << "sqlite_datasource: " << s.str();
std::shared_ptr<sqlite_resultset> rs(dataset_->execute_query(s.str()));
return std::make_shared<sqlite_featureset>(rs,
ctx,
desc_.get_encoding(),
e,
format_,
has_spatial_index_,
using_subquery_);
}
return featureset_ptr();
}
featureset_ptr sqlite_datasource::features_at_point(coord2d const& pt, double tol) const
{
#ifdef MAPNIK_STATS
mapnik::progress_timer __stats__(std::clog, "sqlite_datasource::features_at_point");
#endif
if (dataset_)
{
mapnik::box2d<double> e(pt.x, pt.y, pt.x, pt.y);
e.pad(tol);
std::ostringstream s;
mapnik::context_ptr ctx = std::make_shared<mapnik::context_type>();
s << "SELECT " << geometry_field_;
if (!key_field_.empty())
{
s << "," << key_field_;
ctx->push(key_field_);
}
std::vector<attribute_descriptor>::const_iterator itr = desc_.get_descriptors().begin();
std::vector<attribute_descriptor>::const_iterator end = desc_.get_descriptors().end();
for ( ; itr != end; ++itr)
{
std::string fld_name = itr->get_name();
if (fld_name != key_field_)
{
s << ",[" << itr->get_name() << "]";
ctx->push(itr->get_name());
}
}
s << " FROM ";
std::string query(table_);
if (! key_field_.empty() && has_spatial_index_)
{
// TODO - debug warn if fails
sqlite_utils::apply_spatial_filter(query,
e,
table_,
key_field_,
index_table_,
geometry_table_,
intersects_token_);
}
else
{
query = populate_tokens(table_);
}
s << query ;
if (row_limit_ > 0)
{
s << " LIMIT " << row_limit_;
}
if (row_offset_ > 0)
{
s << " OFFSET " << row_offset_;
}
MAPNIK_LOG_DEBUG(sqlite) << "sqlite_datasource: " << s.str();
std::shared_ptr<sqlite_resultset> rs(dataset_->execute_query(s.str()));
return std::make_shared<sqlite_featureset>(rs,
ctx,
desc_.get_encoding(),
e,
format_,
has_spatial_index_,
using_subquery_);
}
return featureset_ptr();
}