Module zlib

zlib compression and decompression module

Instructions:

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var zlib = require('zlib');

Static function

createDeflate

Create a deflate stream object

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static Stream zlib.createDeflate(Stream to);

Call parameters:

• to : Stream , the stream used to store the processing results

Return result:

• Stream , returns the encapsulated stream object

createDeflateRaw

Create a deflateRaw stream object

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static Stream zlib.createDeflateRaw(Stream to);

Call parameters:

• to : Stream , the stream used to store the processing results

Return result:

• Stream , returns the encapsulated stream object

createGunzip

Create a gunzip stream object

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static Stream zlib.createGunzip(Stream to,
    Integer maxSize = -1);

Call parameters:

• to : Stream , the stream used to store the processing results
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Stream , returns the encapsulated stream object

createGzip

Create a gzip stream object

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static Stream zlib.createGzip(Stream to);

Call parameters:

• to : Stream , the stream used to store the processing results

Return result:

• Stream , returns the encapsulated stream object

createInflate

Create an inflate stream object

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static Stream zlib.createInflate(Stream to,
    Integer maxSize = -1);

Call parameters:

• to : Stream , the stream used to store the processing results
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Stream , returns the encapsulated stream object

createInflateRaw

Create an inflateRaw stream object

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static Stream zlib.createInflateRaw(Stream to,
    Integer maxSize = -1);

Call parameters:

• to : Stream , the stream used to store the processing results
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Stream , returns the encapsulated stream object

deflate

Compress data using deflate algorithm (zlib format)

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static Buffer zlib.deflate(Buffer data,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• data : Buffer , given the data to be compressed
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

Return result:

• Buffer , returns the compressed binary data

deflateTo

Use the deflate algorithm to compress data into a stream object (zlib format)

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static zlib.deflateTo(Buffer data,
    Stream stm,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• data : Buffer , given the data to be compressed
• stm : Stream , specifies the stream for storing compressed data
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

Use the deflate algorithm to compress the data in the source stream into the stream object (zlib format)

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static zlib.deflateTo(Stream src,
    Stream stm,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• src : Stream , the stream where the data to be compressed is given
• stm : Stream , specifies the stream for storing compressed data
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

inflate

Decompress data compressed by deflate algorithm (zlib format)

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static Buffer zlib.inflate(Buffer data,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given compressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Buffer , returns the uncompressed binary data

inflateTo

Decompress the data compressed by the deflate algorithm into a stream object (zlib format)

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static zlib.inflateTo(Buffer data,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given the data to be decompressed
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Decompress the data compressed by the deflate algorithm in the source stream to the stream object (zlib format)

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static zlib.inflateTo(Stream src,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• src : Stream , the stream where the data to be decompressed is given
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

gzip

Compress data using gzip algorithm

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static Buffer zlib.gzip(Buffer data) async;

Call parameters:

• data : Buffer , given the data to be compressed

Return result:

• Buffer , returns the compressed binary data

gzipTo

Use gzip algorithm to compress data into stream objects

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static zlib.gzipTo(Buffer data,
    Stream stm) async;

Call parameters:

• data : Buffer , given the data to be compressed
• stm : Stream , specifies the stream for storing compressed data

Use the gzip algorithm to compress the data in the source stream into the stream object

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static zlib.gzipTo(Stream src,
    Stream stm) async;

Call parameters:

• src : Stream , the stream where the data to be compressed is given
• stm : Stream , specifies the stream for storing compressed data

gunzip

Decompress data compressed by gzip algorithm

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static Buffer zlib.gunzip(Buffer data,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given compressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Buffer , returns the uncompressed binary data

gunzipTo

Decompress the data compressed by the gzip algorithm into the stream object

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static zlib.gunzipTo(Buffer data,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given the data to be decompressed
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Decompress the data compressed by the gzip algorithm in the source stream to the stream object

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static zlib.gunzipTo(Stream src,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• src : Stream , the stream where the data to be decompressed is given
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

deflateRaw

Use the deflate algorithm to compress data (deflateRaw)

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static Buffer zlib.deflateRaw(Buffer data,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• data : Buffer , given the data to be compressed
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

Return result:

• Buffer , returns the compressed binary data

deflateRawTo

Use the deflate algorithm to compress data into a stream object (deflateRaw)

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static zlib.deflateRawTo(Buffer data,
    Stream stm,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• data : Buffer , given the data to be compressed
• stm : Stream , specifies the stream for storing compressed data
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

Use the deflate algorithm to compress the data in the source stream into the stream object (deflateRaw)

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static zlib.deflateRawTo(Stream src,
    Stream stm,
    Integer level = DEFAULT_COMPRESSION) async;

Call parameters:

• src : Stream , the stream where the data to be compressed is given
• stm : Stream , specifies the stream for storing compressed data
• level : Integer, specify the compression level, the default is DEFAULT_COMPRESSION

inflateRaw

Decompress data compressed by the deflate algorithm (inflateRaw)

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static Buffer zlib.inflateRaw(Buffer data,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given compressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Return result:

• Buffer , returns the uncompressed binary data

inflateRawTo

Decompress the data compressed by the deflate algorithm into the stream object (inflateRaw)

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static zlib.inflateRawTo(Buffer data,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• data : Buffer , given the data to be decompressed
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

Decompress the data compressed by the deflate algorithm in the source stream to the stream object (inflateRaw)

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static zlib.inflateRawTo(Stream src,
    Stream stm,
    Integer maxSize = -1) async;

Call parameters:

• src : Stream , the stream where the data to be decompressed is given
• stm : Stream , specifies the stream for storing decompressed data
• maxSize : Integer, specify the decompression size limit, the default is -1, no limit

constant

NO_COMPRESSION

deflate compression level, set no compression

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const zlib.NO_COMPRESSION = 0;

BEST_SPEED

deflate compression level, set the fastest compression

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const zlib.BEST_SPEED = 1;

BEST_COMPRESSION

deflate compression level, set the highest compression

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const zlib.BEST_COMPRESSION = 9;

DEFAULT_COMPRESSION

deflate compression level, set default settings

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const zlib.DEFAULT_COMPRESSION = -1;