JavaScript-facing Parquet reader. More...

Public Member Functions

WasmParquetReader ()=default

Default-construct in an unopened state.

bool open (const std::string &path)

Open a plaintext Parquet file from MEMFS.

int64_t numRows () const

Return total row count across all row groups, or 0 if not open.

int64_t numRowGroups () const

Return the number of row groups in the file, or 0 if not open.

Schema schema () const

Return the file's schema, or an empty Schema if not open.

std::string createdBy () const

Return the "created by" metadata string, or "" if not open.

em::val readColumnAsStrings (size_t rg, size_t col)

Read any column as a JS Array of strings (type-erased).

Typed column readers

Read all values from a single column within a row group, returning a JS Array.

Parameters

rg	Zero-based row group index.
col	Zero-based column index.

Returns: JS Array of typed values, or an empty array on error.

em::val readColumnBool (size_t rg, size_t col)

Read a boolean column as a JS Array of booleans.

em::val readColumnInt32 (size_t rg, size_t col)

Read an int32 column as a JS Array of numbers.

em::val readColumnInt64 (size_t rg, size_t col)

Read an int64 column as a JS Array of doubles (JS has no native int64).

em::val readColumnFloat (size_t rg, size_t col)

Read a float column as a JS Array of numbers.

em::val readColumnDouble (size_t rg, size_t col)

Read a double column as a JS Array of numbers.

em::val readColumnString (size_t rg, size_t col)

Read a string (BYTE_ARRAY) column as a JS Array of strings.

Detailed Description

JavaScript-facing Parquet reader.

Wraps the core ParquetReader with per-type readColumn* methods that return JS arrays via em::val. Supports optional encrypted file opening when built with SIGNET_ENABLE_COMMERCIAL.

Definition at line 409 of file signet_wasm.cpp.

Constructor & Destructor Documentation

◆ WasmParquetReader()

WasmParquetReader::WasmParquetReader ( )

default

Default-construct in an unopened state.

Member Function Documentation

◆ createdBy()

std::string WasmParquetReader::createdBy ( ) const

inline

Return the "created by" metadata string, or "" if not open.

Definition at line 508 of file signet_wasm.cpp.

◆ numRowGroups()

int64_t WasmParquetReader::numRowGroups ( ) const

inline

Return the number of row groups in the file, or 0 if not open.

Definition at line 497 of file signet_wasm.cpp.

◆ numRows()

int64_t WasmParquetReader::numRows ( ) const

inline

Return total row count across all row groups, or 0 if not open.

Definition at line 492 of file signet_wasm.cpp.

◆ open()

bool WasmParquetReader::open ( const std::string & path )

inline

Open a plaintext Parquet file from MEMFS.

Parameters

path	MEMFS path to an existing Parquet file.

Returns: true on success, false if the file is missing or corrupt.

Definition at line 418 of file signet_wasm.cpp.

◆ readColumnAsStrings()

em::val WasmParquetReader::readColumnAsStrings	(	size_t	rg,
		size_t	col
	)

inline

Read any column as a JS Array of strings (type-erased).

Useful for display/preview where the caller does not know the column's physical type at compile time.

Parameters

rg	Zero-based row group index.
col	Zero-based column index.

Returns: JS Array of stringified values, or an empty array on error.

Definition at line 595 of file signet_wasm.cpp.

◆ readColumnBool()

em::val WasmParquetReader::readColumnBool	(	size_t	rg,
		size_t	col
	)

inline

Read a boolean column as a JS Array of booleans.

Definition at line 521 of file signet_wasm.cpp.

◆ readColumnDouble()

em::val WasmParquetReader::readColumnDouble	(	size_t	rg,
		size_t	col
	)

inline

Read a double column as a JS Array of numbers.

Definition at line 565 of file signet_wasm.cpp.

◆ readColumnFloat()

em::val WasmParquetReader::readColumnFloat	(	size_t	rg,
		size_t	col
	)

inline

Read a float column as a JS Array of numbers.

Definition at line 554 of file signet_wasm.cpp.

◆ readColumnInt32()

em::val WasmParquetReader::readColumnInt32	(	size_t	rg,
		size_t	col
	)

inline

Read an int32 column as a JS Array of numbers.

Definition at line 532 of file signet_wasm.cpp.

◆ readColumnInt64()

em::val WasmParquetReader::readColumnInt64	(	size_t	rg,
		size_t	col
	)

inline

Read an int64 column as a JS Array of doubles (JS has no native int64).

Definition at line 543 of file signet_wasm.cpp.

◆ readColumnString()

em::val WasmParquetReader::readColumnString	(	size_t	rg,
		size_t	col
	)

inline

Read a string (BYTE_ARRAY) column as a JS Array of strings.

Definition at line 576 of file signet_wasm.cpp.

◆ schema()

Schema WasmParquetReader::schema ( ) const

inline

Return the file's schema, or an empty Schema if not open.

Definition at line 502 of file signet_wasm.cpp.

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

wasm/signet_wasm.cpp