mapnik/plugins/input/csv/csv_datasource.cpp
2015-08-19 15:24:38 +02:00

752 lines
26 KiB
C++

/*****************************************************************************
*
* This file is part of Mapnik (c++ mapping toolkit)
*
* Copyright (C) 2015 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 "csv_datasource.hpp"
#include "csv_utils.hpp"
// boost
#include <boost/algorithm/string.hpp>
#include <boost/spirit/include/qi.hpp>
// mapnik
#include <mapnik/debug.hpp>
#include <mapnik/util/utf_conv_win.hpp>
#include <mapnik/unicode.hpp>
#include <mapnik/feature_layer_desc.hpp>
#include <mapnik/feature_factory.hpp>
#include <mapnik/geometry.hpp>
#include <mapnik/geometry_correct.hpp>
#include <mapnik/geometry_is_empty.hpp>
#include <mapnik/memory_featureset.hpp>
#include <mapnik/wkt/wkt_factory.hpp>
#include <mapnik/json/geometry_parser.hpp>
#include <mapnik/util/conversions.hpp>
#include <mapnik/boolean.hpp>
#include <mapnik/util/trim.hpp>
#include <mapnik/util/geometry_to_ds_type.hpp>
#include <mapnik/value_types.hpp>
#include <mapnik/csv/csv_grammar.hpp>
// stl
#include <sstream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>
using mapnik::datasource;
using mapnik::parameters;
DATASOURCE_PLUGIN(csv_datasource)
namespace mapnik {
static const csv_line_grammar<char const*> line_g;
csv_line parse_line(std::string & line_str, std::string const& separator)
{
csv_line values;
auto start = line_str.c_str();
auto end = start + line_str.length();
boost::spirit::standard::blank_type blank;
if (!boost::spirit::qi::phrase_parse(start, end, (line_g)(boost::phoenix::cref(separator)), blank, values))
{
throw std::runtime_error("Failed to parse CSV line:\n" + line_str);
}
return values;
}
}
csv_datasource::csv_datasource(parameters const& params)
: datasource(params),
desc_(csv_datasource::name(), *params.get<std::string>("encoding", "utf-8")),
extent_(),
filename_(),
inline_string_(),
row_limit_(*params.get<mapnik::value_integer>("row_limit", 0)),
features_(),
escape_(*params.get<std::string>("escape", "")),
separator_(*params.get<std::string>("separator", "")),
quote_(*params.get<std::string>("quote", "")),
headers_(),
manual_headers_(mapnik::util::trim_copy(*params.get<std::string>("headers", ""))),
strict_(*params.get<mapnik::boolean_type>("strict", false)),
filesize_max_(*params.get<double>("filesize_max", 20.0)), // MB
ctx_(std::make_shared<mapnik::context_type>()),
extent_initialized_(false)
{
boost::optional<std::string> ext = params.get<std::string>("extent");
if (ext && !ext->empty())
{
extent_initialized_ = extent_.from_string(*ext);
}
boost::optional<std::string> inline_string = params.get<std::string>("inline");
if (inline_string)
{
inline_string_ = *inline_string;
}
else
{
boost::optional<std::string> file = params.get<std::string>("file");
if (!file) throw mapnik::datasource_exception("CSV Plugin: missing <file> parameter");
boost::optional<std::string> base = params.get<std::string>("base");
if (base)
filename_ = *base + "/" + *file;
else
filename_ = *file;
}
if (!inline_string_.empty())
{
std::istringstream in(inline_string_);
parse_csv(in, escape_, separator_, quote_);
}
else
{
#if defined (_WINDOWS)
std::ifstream in(mapnik::utf8_to_utf16(filename_),std::ios_base::in | std::ios_base::binary);
#else
std::ifstream in(filename_.c_str(),std::ios_base::in | std::ios_base::binary);
#endif
if (!in.is_open())
{
throw mapnik::datasource_exception("CSV Plugin: could not open: '" + filename_ + "'");
}
parse_csv(in, escape_, separator_, quote_);
in.close();
}
}
csv_datasource::~csv_datasource() { }
namespace detail {
template <typename T>
std::size_t file_length(T & stream)
{
stream.seekg(0, std::ios::end);
return stream.tellg();
}
std::string detect_separator(std::string const& str)
{
std::string separator = ","; // default
int num_commas = std::count(str.begin(), str.end(), ',');
// detect tabs
int num_tabs = std::count(str.begin(), str.end(), '\t');
if (num_tabs > 0)
{
if (num_tabs > num_commas)
{
separator = "\t";
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: auto detected tab separator";
}
}
else // pipes
{
int num_pipes = std::count(str.begin(), str.end(), '|');
if (num_pipes > num_commas)
{
separator = "|";
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: auto detected '|' separator";
}
else // semicolons
{
int num_semicolons = std::count(str.begin(), str.end(), ';');
if (num_semicolons > num_commas)
{
separator = ";";
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: auto detected ';' separator";
}
}
}
return separator;
}
template <typename T>
std::tuple<char,bool> autodect_newline(T & stream, std::size_t file_length)
{
// autodetect newlines
char newline = '\n';
bool has_newline = false;
for (std::size_t lidx = 0; lidx < file_length && lidx < 4000; ++lidx)
{
char c = static_cast<char>(stream.get());
if (c == '\r')
{
newline = '\r';
has_newline = true;
break;
}
if (c == '\n')
{
has_newline = true;
break;
}
}
return std::make_tuple(newline,has_newline);
}
struct geometry_column_locator
{
geometry_column_locator()
: type(UNKNOWN), index(-1), index2(-1) {}
enum { UNKNOWN = 0, WKT, GEOJSON, LON_LAT } type;
std::size_t index;
std::size_t index2;
};
void locate_geometry_column(std::string const& header, std::size_t index, geometry_column_locator & locator)
{
std::string lower_val(header);
std::transform(lower_val.begin(), lower_val.end(), lower_val.begin(), ::tolower);
if (lower_val == "wkt" || (lower_val.find("geom") != std::string::npos))
{
locator.type = geometry_column_locator::WKT;
locator.index = index;
}
else if (lower_val == "geojson")
{
locator.type = geometry_column_locator::GEOJSON;
locator.index = index;
}
else if (lower_val == "x" || lower_val == "lon"
|| lower_val == "lng" || lower_val == "long"
|| (lower_val.find("longitude") != std::string::npos))
{
locator.index = index;
locator.type = geometry_column_locator::LON_LAT;
}
else if (lower_val == "y"
|| lower_val == "lat"
|| (lower_val.find("latitude") != std::string::npos))
{
locator.index2 = index;
locator.type = geometry_column_locator::LON_LAT;
}
}
mapnik::geometry::geometry<double> extract_geometry(std::vector<std::string> const& row, geometry_column_locator const& locator)
{
mapnik::geometry::geometry<double> geom;
if (locator.type == geometry_column_locator::WKT)
{
if (mapnik::from_wkt(row[locator.index], geom))
{
// correct orientations ..
mapnik::geometry::correct(geom);
}
else
{
throw std::runtime_error("FIXME WKT");
}
}
else if (locator.type == geometry_column_locator::GEOJSON)
{
if (!mapnik::json::from_geojson(row[locator.index], geom))
{
throw std::runtime_error("FIXME GEOJSON");
}
}
else if (locator.type == geometry_column_locator::LON_LAT)
{
double x, y;
if (!mapnik::util::string2double(row[locator.index],x))
{
throw std::runtime_error("FIXME Lon");
}
if (!mapnik::util::string2double(row[locator.index2],y))
{
throw std::runtime_error("FIXME Lat");
}
geom = mapnik::geometry::point<double>(x,y);
}
return geom;
}
} // ns detail
template <typename T>
void csv_datasource::parse_csv(T & stream,
std::string const& escape,
std::string const& separator,
std::string const& quote)
{
auto file_length = detail::file_length(stream);
// set back to start
stream.seekg(0, std::ios::beg);
char newline;
bool has_newline;
std::tie(newline, has_newline) = detail::autodect_newline(stream, file_length);
// set back to start
stream.seekg(0, std::ios::beg);
// get first line
std::string csv_line;
std::getline(stream,csv_line,stream.widen(newline));
// if user has not passed a separator manually
// then attempt to detect by reading first line
std::string sep = mapnik::util::trim_copy(separator);
if (sep.empty()) sep = detail::detect_separator(csv_line);
// set back to start
stream.seekg(0, std::ios::beg);
std::string esc = mapnik::util::trim_copy(escape);
if (esc.empty()) esc = "\\";
std::string quo = mapnik::util::trim_copy(quote);
if (quo.empty()) quo = "\"";
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: csv grammar: sep: '" << sep
<< "' quo: '" << quo << "' esc: '" << esc << "'";
int line_number = 1;
detail::geometry_column_locator locator;
if (!manual_headers_.empty())
{
std::size_t index = 0;
auto headers = mapnik::parse_line(manual_headers_, sep);
for (auto const& header : headers)
{
std::string val = mapnik::util::trim_copy(header);
detail::locate_geometry_column(val, index++, locator);
headers_.push_back(val);
}
}
else // parse first line as headers
{
while (std::getline(stream,csv_line,stream.widen(newline)))
{
try
{
auto headers = mapnik::parse_line(csv_line, sep);
// skip blank lines
std::string val;
if (headers.size() > 0 && headers[0].empty()) ++line_number;
else
{
std::size_t index = 0;
for (auto const& header : headers)
{
val = mapnik::util::trim_copy(header);
if (val.empty())
{
if (strict_)
{
std::ostringstream s;
s << "CSV Plugin: expected a column header at line ";
s << line_number << ", column " << index;
s << " - ensure this row contains valid header fields: '";
s << csv_line << "'\n";
throw mapnik::datasource_exception(s.str());
}
else
{
// create a placeholder for the empty header
std::ostringstream s;
s << "_" << index;
headers_.push_back(s.str());
}
}
else
{
detail::locate_geometry_column(val, index, locator);
headers_.push_back(val);
}
++index;
}
++line_number;
break;
}
}
catch (std::exception const& ex)
{
std::string s("CSV Plugin: error parsing headers: ");
s += ex.what();
throw mapnik::datasource_exception(s);
}
}
}
if (locator.type == detail::geometry_column_locator::UNKNOWN)
{
throw mapnik::datasource_exception("CSV Plugin: could not detect column headers with the name of wkt, geojson, x/y, or "
"latitude/longitude - this is required for reading geometry data");
}
mapnik::value_integer feature_count = 0;
bool extent_started = false;
std::size_t num_headers = headers_.size();
std::for_each(headers_.begin(), headers_.end(),
[ & ](std::string const& header){ ctx_->push(header); });
mapnik::transcoder tr(desc_.get_encoding());
// handle rare case of a single line of data and user-provided headers
// where a lack of a newline will mean that std::getline returns false
bool is_first_row = false;
if (!has_newline)
{
stream >> csv_line;
if (!csv_line.empty())
{
is_first_row = true;
}
}
while (std::getline(stream,csv_line, stream.widen(newline)) || is_first_row)
{
is_first_row = false;
if ((row_limit_ > 0) && (line_number > row_limit_))
{
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: row limit hit, exiting at feature: " << feature_count;
break;
}
// skip blank lines
unsigned line_length = csv_line.length();
if (line_length <= 10)
{
std::string trimmed = csv_line;
boost::trim_if(trimmed,boost::algorithm::is_any_of("\",'\r\n "));
if (trimmed.empty())
{
++line_number;
MAPNIK_LOG_DEBUG(csv) << "csv_datasource: empty row encountered at line: " << line_number;
continue;
}
}
try
{
auto values = mapnik::parse_line(csv_line, sep);
unsigned num_fields = values.size();
if (num_fields > num_headers)
{
std::ostringstream s;
s << "CSV Plugin: # of columns("
<< num_fields << ") > # of headers("
<< num_headers << ") parsed for row " << line_number << "\n";
throw mapnik::datasource_exception(s.str());
}
else if (num_fields < num_headers)
{
std::ostringstream s;
s << "CSV Plugin: # of headers("
<< num_headers << ") > # of columns("
<< num_fields << ") parsed for row " << line_number << "\n";
if (strict_)
{
throw mapnik::datasource_exception(s.str());
}
else
{
MAPNIK_LOG_WARN(csv) << s.str();
}
}
auto beg = values.begin();
auto end = values.end();
auto geom = detail::extract_geometry(values, locator);
if (!geom.is<mapnik::geometry::geometry_empty>())
{
mapnik::feature_ptr feature(mapnik::feature_factory::create(ctx_, ++feature_count));
feature->set_geometry(std::move(geom));
std::vector<std::string> collected;
for (unsigned i = 0; i < num_headers; ++i)
{
std::string const& fld_name = headers_.at(i);
collected.push_back(fld_name);
std::string value;
if (beg == end) // there are more headers than column values for this row
{
// add an empty string here to represent a missing value
// not using null type here since nulls are not a csv thing
feature->put(fld_name,tr.transcode(value.c_str()));
if (feature_count == 1)
{
desc_.add_descriptor(mapnik::attribute_descriptor(fld_name,mapnik::String));
}
// continue here instead of break so that all missing values are
// encoded consistenly as empty strings
continue;
}
else
{
value = mapnik::util::trim_copy(*beg++);
}
int value_length = value.length();
// now, add attributes, skipping any WKT or JSON fields
if (locator.index == i && (locator.type == detail::geometry_column_locator::WKT
|| locator.type == detail::geometry_column_locator::GEOJSON) ) continue;
// First we detect likely strings,
// then try parsing likely numbers,
// then try converting to bool,
// finally falling back to string type.
// An empty string or a string of "null" will be parsed
// as a string rather than a true null value.
// Likely strings are either empty values, very long values
// or values with leading zeros like 001 (which are not safe
// to assume are numbers)
bool matched = false;
bool has_dot = value.find(".") != std::string::npos;
if (value.empty() ||
(value_length > 20) ||
(value_length > 1 && !has_dot && value[0] == '0'))
{
matched = true;
feature->put(fld_name,std::move(tr.transcode(value.c_str())));
if (feature_count == 1)
{
desc_.add_descriptor(mapnik::attribute_descriptor(fld_name,mapnik::String));
}
}
else if (csv_utils::is_likely_number(value))
{
bool has_e = value.find("e") != std::string::npos;
if (has_dot || has_e)
{
double float_val = 0.0;
if (mapnik::util::string2double(value,float_val))
{
matched = true;
feature->put(fld_name,float_val);
if (feature_count == 1)
{
desc_.add_descriptor(
mapnik::attribute_descriptor(
fld_name,mapnik::Double));
}
}
}
else
{
mapnik::value_integer int_val = 0;
if (mapnik::util::string2int(value,int_val))
{
matched = true;
feature->put(fld_name,int_val);
if (feature_count == 1)
{
desc_.add_descriptor(
mapnik::attribute_descriptor(
fld_name,mapnik::Integer));
}
}
}
}
if (!matched)
{
// NOTE: we don't use mapnik::util::string2bool
// here because we don't want to treat 'on' and 'off'
// as booleans, only 'true' and 'false'
bool bool_val = false;
std::string lower_val = value;
std::transform(lower_val.begin(), lower_val.end(), lower_val.begin(), ::tolower);
if (lower_val == "true")
{
matched = true;
bool_val = true;
}
else if (lower_val == "false")
{
matched = true;
bool_val = false;
}
if (matched)
{
feature->put(fld_name,bool_val);
if (feature_count == 1)
{
desc_.add_descriptor(
mapnik::attribute_descriptor(
fld_name,mapnik::Boolean));
}
}
else
{
// fallback to normal string
feature->put(fld_name,std::move(tr.transcode(value.c_str())));
if (feature_count == 1)
{
desc_.add_descriptor(
mapnik::attribute_descriptor(
fld_name,mapnik::String));
}
}
}
}
if (!extent_initialized_)
{
if (!extent_started)
{
extent_started = true;
extent_ = feature->envelope();
}
else
{
extent_.expand_to_include(feature->envelope());
}
}
features_.push_back(feature);
}
else
{
std::ostringstream s;
s << "CSV Plugin: expected geometry column: could not parse row "
<< line_number << " "
<< values[locator.index] << "'";
if (strict_)
{
throw mapnik::datasource_exception(s.str());
}
else
{
MAPNIK_LOG_ERROR(csv) << s.str();
}
}
++line_number;
}
catch (mapnik::datasource_exception const& ex )
{
if (strict_)
{
throw mapnik::datasource_exception(ex.what());
}
else
{
MAPNIK_LOG_ERROR(csv) << ex.what();
}
}
catch(std::exception const& ex)
{
std::ostringstream s;
s << "CSV Plugin: unexpected error parsing line: " << line_number
<< " - found " << headers_.size() << " with values like: " << csv_line << "\n"
<< " and got error like: " << ex.what();
if (strict_)
{
throw mapnik::datasource_exception(s.str());
}
else
{
MAPNIK_LOG_ERROR(csv) << s.str();
}
}
}
if (feature_count < 1)
{
MAPNIK_LOG_ERROR(csv) << "CSV Plugin: could not parse any lines of data";
}
}
const char * csv_datasource::name()
{
return "csv";
}
datasource::datasource_t csv_datasource::type() const
{
return datasource::Vector;
}
mapnik::box2d<double> csv_datasource::envelope() const
{
return extent_;
}
mapnik::layer_descriptor csv_datasource::get_descriptor() const
{
return desc_;
}
boost::optional<mapnik::datasource_geometry_t> csv_datasource::get_geometry_type() const
{
boost::optional<mapnik::datasource_geometry_t> result;
int multi_type = 0;
unsigned num_features = features_.size();
for (unsigned i = 0; i < num_features && i < 5; ++i)
{
result = mapnik::util::to_ds_type(features_[i]->get_geometry());
if (result)
{
int type = static_cast<int>(*result);
if (multi_type > 0 && multi_type != type)
{
result.reset(mapnik::datasource_geometry_t::Collection);
return result;
}
multi_type = type;
}
}
return result;
}
mapnik::featureset_ptr csv_datasource::features(mapnik::query const& q) const
{
std::set<std::string> const& attribute_names = q.property_names();
std::set<std::string>::const_iterator pos = attribute_names.begin();
while (pos != attribute_names.end())
{
bool found_name = false;
for (std::size_t i = 0; i < headers_.size(); ++i)
{
if (headers_[i] == *pos)
{
found_name = true;
break;
}
}
if (! found_name)
{
std::ostringstream s;
s << "CSV Plugin: no attribute '" << *pos << "'. Valid attributes are: "
<< boost::algorithm::join(headers_, ",") << ".";
throw mapnik::datasource_exception(s.str());
}
++pos;
}
return std::make_shared<mapnik::memory_featureset>(q.get_bbox(),features_);
}
mapnik::featureset_ptr csv_datasource::features_at_point(mapnik::coord2d const& pt, double tol) const
{
throw mapnik::datasource_exception("CSV Plugin: features_at_point is not supported yet");
}