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https://github.com/asadbek064/hyparquet.git
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57 lines
2.0 KiB
TypeScript
57 lines
2.0 KiB
TypeScript
export { AsyncBuffer, FileMetaData } from './types'
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/**
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* Read parquet data rows from a file
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*
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* @param {ArrayBuffer} arrayBuffer parquet file contents
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* @returns {any[][]} row data
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*/
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export function parquetRead(arrayBuffer: ArrayBuffer): any[][]
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/**
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* Read parquet metadata from an async buffer.
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*
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* An AsyncBuffer is like an ArrayBuffer, but the slices are loaded
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* asynchronously, possibly over the network.
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*
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* To make this efficient, we initially request the last 512kb of the file,
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* which is likely to contain the metadata. If the metadata length exceeds the
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* initial fetch, 512kb, we request the rest of the metadata from the AsyncBuffer.
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*
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* This ensures that we either make one 512kb initial request for the metadata,
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* or two requests for exactly the metadata size.
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*
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* @param {AsyncBuffer} asyncBuffer parquet file contents
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* @param {number} initialFetchSize initial fetch size in bytes (default 512kb)
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* @returns {Promise<FileMetaData>} metadata object
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*/
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export async function parquetMetadataAsync(asyncBuffer: AsyncBuffer, initialFetchSize: number = 1 << 19 /* 512kb */): Promise<FileMetaData>
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/**
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* Read parquet metadata from a buffer
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*
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* @param {ArrayBuffer} arrayBuffer parquet file contents
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* @returns {FileMetaData} metadata object
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*/
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export function parquetMetadata(arrayBuffer: ArrayBuffer): FileMetaData
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/**
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* Decompress snappy data.
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* Accepts an output buffer to avoid allocating a new buffer for each call.
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*
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* @param {Uint8Array} inputArray compressed data
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* @param {Uint8Array} outputArray output buffer
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* @returns {boolean} true if successful
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*/
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export function snappyUncompress(inputArray: Uint8Array, outputArray: Uint8Array): boolean
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/**
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* Replace bigints with numbers.
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* When parsing parquet files, bigints are used to represent 64-bit integers.
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* However, JSON does not support bigints, so it's helpful to convert to numbers.
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*
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* @param {any} obj object to convert
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* @returns {unknown} converted object
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*/
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export function toJson(obj: any): unknown
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