node:zlib

#Import

import zlib from "nstdlib/node/zlib";

Note

The API is available, but not everything works. No compression binding, so every stream and one-shot throws ERR_NSTDLIB_NO_BINDING. The 154 exports and all of constants and codes are real and compared against the host builtin. crc32 is a checksum rather than a codec and is implemented. native/ backs Zlib and BrotliDecoder on node_binding_zlib_*, over the zlib and the brotli decoder compiled into that binary. The Brotli encoder and both directions of Zstandard stay refused there too.

#Support

node:zlib. nstd: works; Node test suite 90.5% passing. Browser: works; export coverage 100%; Node test suite 53.6% passing.

nstd: Gives the same output as Node.js in side-by-side tests: zlib.
Browser: Loads with a minimal process object. 162 of Node's 162 exports are available. 1 of 1 behavior checks match Node.js.

#Exports (162)

Every name Node.js exports from this module, and what you get when you read it, as a named import or as a property of the default import:

✅ A value, both ways. An export that throws an error naming the missing feature also counts.
⚠️ A value one way, undefined the other.
❔ undefined both ways.
❌ Not exported at all.
– Not measured.

Show all 162 exports

Export	Node.js	Browser
`BrotliCompress`	✅	✅
`BrotliDecompress`	✅	✅
`DEFLATE`	✅	✅
`DEFLATERAW`	✅	✅
`Deflate`	✅	✅
`DeflateRaw`	✅	✅
`GUNZIP`	✅	✅
`GZIP`	✅	✅
`Gunzip`	✅	✅
`Gzip`	✅	✅
`INFLATE`	✅	✅
`INFLATERAW`	✅	✅
`Inflate`	✅	✅
`InflateRaw`	✅	✅
`UNZIP`	✅	✅
`Unzip`	✅	✅
`ZLIB_VERNUM`	✅	✅
`ZSTD_CLEVEL_DEFAULT`	✅	✅
`ZSTD_COMPRESS`	✅	✅
`ZSTD_DECOMPRESS`	✅	✅
`ZSTD_btlazy2`	✅	✅
`ZSTD_btopt`	✅	✅
`ZSTD_btultra`	✅	✅
`ZSTD_btultra2`	✅	✅
`ZSTD_c_chainLog`	✅	✅
`ZSTD_c_checksumFlag`	✅	✅
`ZSTD_c_compressionLevel`	✅	✅
`ZSTD_c_contentSizeFlag`	✅	✅
`ZSTD_c_dictIDFlag`	✅	✅
`ZSTD_c_enableLongDistanceMatching`	✅	✅
`ZSTD_c_hashLog`	✅	✅
`ZSTD_c_jobSize`	✅	✅
`ZSTD_c_ldmBucketSizeLog`	✅	✅
`ZSTD_c_ldmHashLog`	✅	✅
`ZSTD_c_ldmHashRateLog`	✅	✅
`ZSTD_c_ldmMinMatch`	✅	✅
`ZSTD_c_minMatch`	✅	✅
`ZSTD_c_nbWorkers`	✅	✅
`ZSTD_c_overlapLog`	✅	✅
`ZSTD_c_searchLog`	✅	✅
`ZSTD_c_strategy`	✅	✅
`ZSTD_c_targetLength`	✅	✅
`ZSTD_c_windowLog`	✅	✅
`ZSTD_d_windowLogMax`	✅	✅
`ZSTD_dfast`	✅	✅
`ZSTD_e_continue`	✅	✅
`ZSTD_e_end`	✅	✅
`ZSTD_e_flush`	✅	✅
`ZSTD_error_GENERIC`	✅	✅
`ZSTD_error_checksum_wrong`	✅	✅
`ZSTD_error_corruption_detected`	✅	✅
`ZSTD_error_dictionaryCreation_failed`	✅	✅
`ZSTD_error_dictionary_corrupted`	✅	✅
`ZSTD_error_dictionary_wrong`	✅	✅
`ZSTD_error_dstBuffer_null`	✅	✅
`ZSTD_error_dstSize_tooSmall`	✅	✅
`ZSTD_error_frameParameter_unsupported`	✅	✅
`ZSTD_error_frameParameter_windowTooLarge`	✅	✅
`ZSTD_error_init_missing`	✅	✅
`ZSTD_error_literals_headerWrong`	✅	✅
`ZSTD_error_maxSymbolValue_tooLarge`	✅	✅
`ZSTD_error_maxSymbolValue_tooSmall`	✅	✅
`ZSTD_error_memory_allocation`	✅	✅
`ZSTD_error_noForwardProgress_destFull`	✅	✅
`ZSTD_error_noForwardProgress_inputEmpty`	✅	✅
`ZSTD_error_no_error`	✅	✅
`ZSTD_error_parameter_combination_unsupported`	✅	✅
`ZSTD_error_parameter_outOfBound`	✅	✅
`ZSTD_error_parameter_unsupported`	✅	✅
`ZSTD_error_prefix_unknown`	✅	✅
`ZSTD_error_srcSize_wrong`	✅	✅
`ZSTD_error_stabilityCondition_notRespected`	✅	✅
`ZSTD_error_stage_wrong`	✅	✅
`ZSTD_error_tableLog_tooLarge`	✅	✅
`ZSTD_error_version_unsupported`	✅	✅
`ZSTD_error_workSpace_tooSmall`	✅	✅
`ZSTD_fast`	✅	✅
`ZSTD_greedy`	✅	✅
`ZSTD_lazy`	✅	✅
`ZSTD_lazy2`	✅	✅
`Z_BEST_COMPRESSION`	✅	✅
`Z_BEST_SPEED`	✅	✅
`Z_BLOCK`	✅	✅
`Z_BUF_ERROR`	✅	✅
`Z_DATA_ERROR`	✅	✅
`Z_DEFAULT_CHUNK`	✅	✅
`Z_DEFAULT_COMPRESSION`	✅	✅
`Z_DEFAULT_LEVEL`	✅	✅
`Z_DEFAULT_MEMLEVEL`	✅	✅
`Z_DEFAULT_STRATEGY`	✅	✅
`Z_DEFAULT_WINDOWBITS`	✅	✅
`Z_ERRNO`	✅	✅
`Z_FILTERED`	✅	✅
`Z_FINISH`	✅	✅
`Z_FIXED`	✅	✅
`Z_FULL_FLUSH`	✅	✅
`Z_HUFFMAN_ONLY`	✅	✅
`Z_MAX_CHUNK`	✅	✅
`Z_MAX_LEVEL`	✅	✅
`Z_MAX_MEMLEVEL`	✅	✅
`Z_MAX_WINDOWBITS`	✅	✅
`Z_MEM_ERROR`	✅	✅
`Z_MIN_CHUNK`	✅	✅
`Z_MIN_LEVEL`	✅	✅
`Z_MIN_MEMLEVEL`	✅	✅
`Z_MIN_WINDOWBITS`	✅	✅
`Z_NEED_DICT`	✅	✅
`Z_NO_COMPRESSION`	✅	✅
`Z_NO_FLUSH`	✅	✅
`Z_OK`	✅	✅
`Z_PARTIAL_FLUSH`	✅	✅
`Z_RLE`	✅	✅
`Z_STREAM_END`	✅	✅
`Z_STREAM_ERROR`	✅	✅
`Z_SYNC_FLUSH`	✅	✅
`Z_VERSION_ERROR`	✅	✅
`ZipBuffer`	✅	✅
`ZipEntry`	✅	✅
`ZipFile`	✅	✅
`ZstdCompress`	✅	✅
`ZstdDecompress`	✅	✅
`brotliCompress`	✅	✅
`brotliCompressSync`	✅	✅
`brotliDecompress`	✅	✅
`brotliDecompressSync`	✅	✅
`codes`	✅	✅
`constants`	✅	✅
`crc32`	✅	✅
`createBrotliCompress`	✅	✅
`createBrotliDecompress`	✅	✅
`createDeflate`	✅	✅
`createDeflateRaw`	✅	✅
`createGunzip`	✅	✅
`createGzip`	✅	✅
`createInflate`	✅	✅
`createInflateRaw`	✅	✅
`createUnzip`	✅	✅
`createZipArchive`	✅	✅
`createZipArchiveSync`	✅	✅
`createZstdCompress`	✅	✅
`createZstdDecompress`	✅	✅
`deflate`	✅	✅
`deflateRaw`	✅	✅
`deflateRawSync`	✅	✅
`deflateSync`	✅	✅
`getMaxZipContentSize`	✅	✅
`gunzip`	✅	✅
`gunzipSync`	✅	✅
`gzip`	✅	✅
`gzipSync`	✅	✅
`inflate`	✅	✅
`inflateRaw`	✅	✅
`inflateRawSync`	✅	✅
`inflateSync`	✅	✅
`setMaxZipContentSize`	✅	✅
`unzip`	✅	✅
`unzipSync`	✅	✅
`zipFiles`	✅	✅
`zstdCompress`	✅	✅
`zstdCompressSync`	✅	✅
`zstdDecompress`	✅	✅
`zstdDecompressSync`	✅	✅

#Diagnostics

nstdlib running inside Node.js. This isn't an environment it's meant for, so it isn't shown above, but it tells a library problem from an environment one:

coverage: 162/162 of the host's export names answer inside host node. API only. No compression binding, so every stream and one-shot throws ERR_NSTDLIB_NO_BINDING. The 154 exports and all of constants and codes are real and compared against the host builtin. crc32 is a checksum rather than a codec and is implemented. native/ backs Zlib and BrotliDecoder on node_binding_zlib_*, over the zlib and the brotli decoder compiled into that binary. The Brotli encoder and both directions of Zstandard stay refused there too.
smoke: Imports in a clean child process.
node-suite: 46/85 of Node's own eligible tests pass with ./dist inside host node. A failure there and in the page is the library's, one only in the page is the engine's.
wasm-differentials: Zlib: pass against the host's own builtin with nstdlib-wasm's blob installed. The published binding refuses without it. Ok nstdlib/node/zlib on Zlib + crc32 == the host's node:zlib.
wasm-differentials: Brotli: pass against the host's own builtin with nstdlib-wasm's blob installed. The published binding refuses without it. Ok nstdlib/node/zlib on BrotliEncoder + BrotliDecoder == the host's node:zlib.
wasm-differentials: Zstd: pass against the host's own builtin with nstdlib-wasm's blob installed. The published binding refuses without it. Ok nstdlib/node/zlib on ZstdCompress + ZstdDecompress == the host's node:zlib.

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