dasmig::core::csv_writer Class Reference

Writes results as CSV, one row each, with columns flattened from their JSON (see flatten_json()). More...

#include <sinks.hpp>

Public Member Functions
	csv_writer (std::ostream &out)
	Write to out, which must outlive the writer.
void	write_json (std::string_view json)
	Write one record given as JSON.
template<json_result T>
void	operator() (std::uint64_t, const T &item)
	Sink call: write the item's to_json().
const std::vector< std::string > &	columns () const noexcept
	The columns, known after the first record.
std::size_t	records () const noexcept
	Records written so far (not counting the header).

Detailed Description

Writes results as CSV, one row each, with columns flattened from their JSON (see flatten_json()).

The header comes from the first record. Later records are matched to it by column name: a column the record lacks is empty, and a column the header lacks is dropped. Fields are quoted when they hold a comma, a quote or a line break; rows end with \n.

Definition at line 345 of file sinks.hpp.

Constructor & Destructor Documentation

csv_writer()

dasmig::core::csv_writer::csv_writer ( std::ostream &  out )

inlineexplicit

Write to out, which must outlive the writer.

Parameters

out	Destination stream.

Definition at line 350 of file sinks.hpp.

Member Function Documentation

columns()

const std::vector< std::string > & dasmig::core::csv_writer::columns ( ) const

inlinenoexcept

The columns, known after the first record.

Returns

The column names.

Definition at line 402 of file sinks.hpp.

operator()()

template<json_result T>

void dasmig::core::csv_writer::operator() ( std::uint64_t  , const T &  item  )

inline

Sink call: write the item's to_json().

Parameters

item	The result.

Definition at line 395 of file sinks.hpp.

records()

std::size_t dasmig::core::csv_writer::records ( ) const

inlinenoexcept

Records written so far (not counting the header).

Returns

The count.

Definition at line 406 of file sinks.hpp.

write_json()

void dasmig::core::csv_writer::write_json ( std::string_view  json )

inline

Write one record given as JSON.

Parameters

json	A JSON document.

Exceptions

std::invalid_argument

If json is not valid JSON.

Definition at line 355 of file sinks.hpp.

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The documentation for this class was generated from the following file:

• dasmig/core/sinks.hpp